use std::{net::IpAddr, sync::atomic::Ordering, time::{Duration, Instant}};
use axum::{
    body::Body,
    extract::{Path, Query, Request, State, WebSocketUpgrade, ws::{Message, WebSocket}},
    http::{header, HeaderMap, HeaderValue, StatusCode},
    middleware::{self, Next},
    response::{Redirect, Response},
    routing::{get, post},
    Json, Router,
};
use base64::{engine::general_purpose::URL_SAFE_NO_PAD, Engine as _};
use chrono::{Duration as ChronoDuration, NaiveTime, Utc};
use futures_util::StreamExt;
use rand::{rngs::OsRng, RngCore};
use serde::Deserialize;
use sha2::{Digest, Sha256};
use serde_json::{json, Value};
use tower_http::{compression::CompressionLayer, trace::TraceLayer};
use uuid::Uuid;
use crate::{
    engine,
    error::AppError,
    home_assistant,
    influxdb,
    notifications,
    models::{ApiTokenInfo, Automation, ClimateGroup, ConfigurationExport, DebugSettings, Device, DeviceCommand, DevicePatch, DiscoveryRequest, GroupControlPatch, ManualDeviceRequest, HaReading, NotificationSettings, Reading, RuntimeSettings, Schedule, Zone, ZoneControlPatch, ZoneReading},
    protocol::merge_discovered,
    state::AppState,
};

const INDEX_HTML: &str = include_str!("../web/index.html");
const APP_JS: &str = include_str!("../web/app.js");
const THEME_INIT_JS: &str = include_str!("../web/theme-init.js");
const STYLES_CSS: &str = include_str!("../web/styles.css");
const MANIFEST: &str = include_str!("../web/manifest.webmanifest");
const SERVICE_WORKER: &str = include_str!("../web/sw.js");
const FAVICON: &str = include_str!("../web/favicon.svg");
include!(concat!(env!("OUT_DIR"), "/languages.rs"));

pub fn router(state: AppState) -> Router {
    let protected = Router::new()
        .route("/api/bootstrap", get(bootstrap))
        .route("/api/system/info", get(system_info))
        .route("/api/discovery", post(discover))
        .route("/api/devices", get(list_devices).post(add_device))
        .route("/api/devices/:id", get(get_device).patch(patch_device).delete(delete_device))
        .route("/api/devices/:id/bind", post(bind_device))
        .route("/api/devices/:id/poll", post(poll_device))
        .route("/api/devices/:id/command", post(command_device))
        .route("/api/zones", get(list_zones).post(create_zone))
        .route("/api/zones/:id", get(get_zone).put(update_zone).delete(delete_zone))
        .route("/api/zones/:id/control", post(update_zone_control))
        .route("/api/zones/:id/schedule-template", post(apply_schedule_template))
        .route("/api/groups", get(list_groups).post(create_group))
        .route("/api/groups/:id", get(get_group).put(update_group).delete(delete_group))
        .route("/api/groups/:id/control", post(update_group_control))
        .route("/api/house/control", post(update_house_control))
        .route("/api/house/power", post(update_house_power))
        .route("/api/house/preset", post(update_house_preset))
        .route("/api/schedules", get(list_schedules).post(create_schedule))
        .route("/api/schedules/:id", get(get_schedule).put(update_schedule).delete(delete_schedule))
        .route("/api/automations", get(list_automations).post(create_automation))
        .route("/api/automations/:id", get(get_automation).put(update_automation).delete(delete_automation))
        .route("/api/readings", get(readings))
        .route("/api/history", get(history))
        .route("/api/control-plan", get(control_plan))
        .route("/api/events", get(events))
        .route("/api/events/retention", get(get_event_retention).put(update_event_retention))
        .route("/api/settings", get(get_settings).put(update_settings))
        .route("/api/settings/export", get(export_settings))
        .route("/api/settings/import", post(import_settings))
        .route("/api/debug", get(get_debug).put(update_debug))
        .route("/api/access-tokens", get(list_access_tokens).post(create_access_token))
        .route("/api/access-tokens/:id", axum::routing::delete(delete_access_token))
        .route("/api/integrations/home-assistant/test", post(test_home_assistant))
        .route("/api/integrations/notifications/test", post(test_notifications))
        .route_layer(middleware::from_fn_with_state(state.clone(), auth));

    let home_assistant_api = Router::new()
        .route("/api/integrations/home-assistant/devices", get(list_devices))
        .route("/api/integrations/home-assistant/devices/:id/command", post(command_home_assistant_device))
        .route("/api/integrations/home-assistant/control-plan", get(control_plan))
        .route("/api/integrations/home-assistant/groups", get(list_home_assistant_groups))
        .route("/api/integrations/home-assistant/groups/:id/control", post(update_home_assistant_group_control))
        .route("/api/integrations/home-assistant/house/control", post(update_house_control))
        .route("/api/integrations/home-assistant/house/preset", post(update_house_preset))
        .route("/api/integrations/home-assistant/house/power", post(update_house_power))
        .route("/api/integrations/home-assistant/zones/:id/control", post(update_zone_control))
        .route_layer(middleware::from_fn_with_state(state.clone(), home_assistant_auth));

    let app = Router::new()
        .route("/api/health", get(health))
        .route("/ws", get(websocket))
        .route("/", get(index))
        .route("/index.html", get(index))
        .route("/app.js", get(app_js))
        .route("/theme-init.js", get(theme_init_js))
        .route("/styles.css", get(styles_css))
        .route("/manifest.webmanifest", get(manifest))
        .route("/sw.js", get(service_worker))
        .route("/favicon.svg", get(favicon))
        .route("/lang/index.json", get(language_index))
        .route("/lang/:file", get(language_file))
        .merge(protected)
        .merge(home_assistant_api)
        .fallback(index)
        ;

    let app = if state.config.base_path.is_empty() {
        app
    } else {
        let base = state.config.base_path.clone();
        let redirect_to = format!("{base}/");
        Router::new()
            .route(&base, get(move || {
                let redirect_to = redirect_to.clone();
                async move { Redirect::permanent(&redirect_to) }
            }))
            .nest(&base, app)
    };

    app
        .layer(CompressionLayer::new())
        .layer(TraceLayer::new_for_http())
        .layer(middleware::from_fn(security_headers))
        .layer(middleware::from_fn_with_state(state.clone(), debug_api_requests))
        .with_state(state)
}

async fn debug_api_requests(State(state): State<AppState>, request: Request, next: Next) -> Response {
    if !state.settings.read().await.debug.overlay_enabled {
        return next.run(request).await;
    }
    let method = request.method().clone();
    let path = request.uri().path().to_string();
    let started = Instant::now();
    let response = next.run(request).await;
    state.broadcast("api.request", json!({
        "method": method.as_str(),
        "path": path,
        "status": response.status().as_u16(),
        "duration_ms": started.elapsed().as_millis(),
    }));
    response
}

async fn auth(State(state): State<AppState>, request: Request, next: Next) -> Result<Response, AppError> {
    let expected = state.config.app_token.trim();
    if expected.is_empty() {
        return Ok(next.run(request).await);
    }
    let supplied = request_token(&request);
    if supplied.as_deref() != Some(expected) {
        return Err(AppError::Unauthorized);
    }
    Ok(next.run(request).await)
}

async fn home_assistant_auth(
    State(state): State<AppState>,
    request: Request,
    next: Next,
) -> Result<Response, AppError> {
    let supplied = request_token(&request).ok_or(AppError::Unauthorized)?;
    let admin_token = state.config.app_token.trim();
    if !admin_token.is_empty() && supplied == admin_token {
        return Ok(next.run(request).await);
    }
    if state.db.api_token_exists(&hash_token(&supplied))? {
        return Ok(next.run(request).await);
    }
    Err(AppError::Unauthorized)
}

fn request_token(request: &Request) -> Option<String> {
    request.headers().get(header::AUTHORIZATION)
        .and_then(|value| value.to_str().ok())
        .and_then(|value| value.strip_prefix("Bearer "))
        .or_else(|| request.headers().get("x-api-token").and_then(|value| value.to_str().ok()))
        .map(str::to_owned)
}

fn hash_token(token: &str) -> String {
    URL_SAFE_NO_PAD.encode(Sha256::digest(token.as_bytes()))
}

fn generate_access_token() -> String {
    let mut bytes = [0u8; 32];
    let mut rng = OsRng;
    rng.fill_bytes(&mut bytes);
    format!("gree_controller_{}", URL_SAFE_NO_PAD.encode(bytes))
}

async fn health(State(state): State<AppState>) -> Json<Value> {
    Json(json!({
        "status": "ok",
        "name": "gree-controller",
        "version": env!("CARGO_PKG_VERSION"),
        "uptime_seconds": state.started.elapsed().as_secs(),
        "control_ready": state.initial_device_sync_complete.load(Ordering::Acquire),
        "time": Utc::now(),
    }))
}

async fn bootstrap(State(state): State<AppState>) -> Result<Json<Value>, AppError> {
    Ok(Json(build_bootstrap(&state).await?))
}

async fn build_bootstrap(state: &AppState) -> Result<Value, AppError> {
    let settings = state.settings.read().await.clone();
    Ok(json!({
        "devices": state.db.list_devices()?,
        "zones": state.db.list_zones()?,
        "groups": state.db.list_groups()?,
        "schedules": state.db.list_schedules()?,
        "automations": state.db.list_automations()?,
        "access_tokens": state.db.list_api_tokens()?,
        "settings": public_settings(&settings),
        "outdoor_temperature": *state.outdoor_temperature.read().await,
        "system": {
            "version": env!("CARGO_PKG_VERSION"),
            "uptime_seconds": state.started.elapsed().as_secs(),
            "auth_required": !state.config.app_token.trim().is_empty(),
            "control_ready": state.initial_device_sync_complete.load(Ordering::Acquire),
        }
    }))
}

async fn system_info(State(state): State<AppState>) -> Result<Json<Value>, AppError> {
    let devices = state.db.list_devices()?;
    Ok(Json(json!({
        "version": env!("CARGO_PKG_VERSION"),
        "uptime_seconds": state.started.elapsed().as_secs(),
        "database": state.config.database.display().to_string(),
        "device_count": devices.len(),
        "online_count": devices.iter().filter(|v| v.online).count(),
        "simulator_count": devices.iter().filter(|v| v.simulated).count(),
        "control_ready": state.initial_device_sync_complete.load(Ordering::Acquire),
        "bind": state.config.bind.to_string(),
        "gree_interface": if state.config.gree_interface.trim().is_empty() { "auto" } else { state.config.gree_interface.trim() },
    })))
}

async fn discover(State(state): State<AppState>, Json(request): Json<DiscoveryRequest>) -> Result<Json<Value>, AppError> {
    let settings = state.settings.read().await.clone();
    let timeout_ms = request.timeout_ms.unwrap_or(settings.discovery_timeout_ms).clamp(500, 30_000);
    let broadcast = request.broadcast.unwrap_or(settings.discovery_broadcast);
    let protocol_version = request.protocol_version.unwrap_or(0).min(2);
    let passes = request.passes.unwrap_or(3).clamp(1, 10);
    let discovered = state.gree.discover(&broadcast, Duration::from_millis(timeout_ms), protocol_version, passes).await
        .map_err(|e| AppError::Device(e.to_string()))?;
    let mut saved = Vec::new();
    let mut new_device_ids = Vec::new();
    for item in discovered {
        let existing = state.db.get_device_by_mac(&item.mac)?;
        let is_new = existing.is_none();
        let mut merged = merge_discovered(existing, item);
        let _device_guard = state.lock_device_operation(&merged.id).await;
        // A poll/command may have updated the same known device between discovery and
        // acquiring its operation lock. Re-merge against the freshest persisted state.
        if !is_new {
            if let Some(current) = state.db.get_device(&merged.id)? {
                merged = merge_discovered(Some(current), merged);
            }
        }
        // Bind right after discovery. GREE modules can have a short bind window;
        // bind() also refreshes it with a direct scan before the handshake.
        if !merged.simulated && merged.key.as_deref().unwrap_or_default().is_empty() {
            match state.gree.bind(&merged).await {
                Ok(bound) => {
                    merged.key = Some(bound.key);
                    merged.protocol_version = bound.protocol_version;
                    merged.communication_failures = 0;
                    merged.last_error = None;
                }
                Err(err) => {
                    merged.last_error = Some(format!("discovered, bind pending: {err}"));
                    state.log("warn", "device.bind_after_discovery", &format!("{}: {err}", merged.name), json!({"device_id": merged.id}));
                }
            }
        }
        state.db.save_device(&merged)?;
        if is_new { new_device_ids.push(merged.id.clone()); }
        saved.push(merged);
    }
    state.log("info", "discovery.complete", &format!("Discovery found {} device(s)", saved.len()), json!({"count": saved.len(), "protocol_version": protocol_version, "passes": passes, "new_devices": new_device_ids.len()}));
    state.broadcast("devices.discovered", json!({"devices": saved}));
    Ok(Json(json!({"count": saved.len(), "devices": saved, "new_device_ids": new_device_ids})))
}

async fn list_devices(State(state): State<AppState>) -> Result<Json<Vec<Device>>, AppError> {
    Ok(Json(state.db.list_devices()?))
}

async fn add_device(State(state): State<AppState>, Json(input): Json<ManualDeviceRequest>) -> Result<(StatusCode, Json<Device>), AppError> {
    if input.name.trim().is_empty() || input.mac.trim().is_empty() || input.ip.trim().is_empty() {
        return Err(AppError::BadRequest("name, mac and ip are required".into()));
    }
    input.ip.parse::<IpAddr>().map_err(|_| AppError::BadRequest("invalid IP address".into()))?;
    if state.db.get_device_by_mac(&input.mac)?.is_some() {
        return Err(AppError::BadRequest("a device with this MAC already exists".into()));
    }
    let now = Utc::now();
    let normalized_mac = input.mac.replace([':', '-'], "").to_ascii_uppercase();
    let device = Device {
        id: format!("gree-{}", normalized_mac.to_ascii_lowercase()),
        mac: normalized_mac,
        name: input.name.trim().to_string(),
        ip: input.ip,
        port: input.port,
        protocol_version: input.protocol_version.min(2),
        model: String::new(),
        firmware: String::new(),
        key: input.key.filter(|v| !v.trim().is_empty()),
        cid: Some("app".into()),
        enabled: true,
        simulated: input.simulated,
        power: false,
        mode: "cool".into(),
        target_temperature: 24.0,
        fan_speed: 0,
        swing_vertical: false,
        swing_horizontal: false,
        quiet: false,
        turbo: false,
        light: true,
        air: false,
        xfan: false,
        health: false,
        sleep: false,
        supports_light: None,
        supports_quiet: None,
        supports_turbo: None,
        supports_air: None,
        supports_xfan: None,
        supports_health: None,
        supports_sleep: None,
        current_temperature: if input.simulated { Some(25.0) } else { None },
        outdoor_temperature: None,
        temperature_sensor_offset: None,
        online: input.simulated,
        response_time_ms: if input.simulated { Some(0) } else { None },
        last_seen: if input.simulated { Some(now) } else { None },
        last_error: None,
        communication_failures: 0,
        created_at: now,
        updated_at: now,
    };
    state.db.save_device(&device)?;
    state.log("info", "device.created", &format!("Added {}", device.name), json!({"device_id": device.id}));
    state.broadcast("device.created", serde_json::to_value(&device)?);
    Ok((StatusCode::CREATED, Json(device)))
}

async fn get_device(State(state): State<AppState>, Path(id): Path<String>) -> Result<Json<Device>, AppError> {
    state.db.get_device(&id)?.map(Json).ok_or_else(|| AppError::NotFound(format!("device {id}")))
}

async fn patch_device(State(state): State<AppState>, Path(id): Path<String>, Json(patch): Json<DevicePatch>) -> Result<Json<Device>, AppError> {
    let _device_guard = state.lock_device_operation(&id).await;
    let mut device = state.db.get_device(&id)?.ok_or_else(|| AppError::NotFound(format!("device {id}")))?;
    if let Some(v) = patch.name { if !v.trim().is_empty() { device.name = v.trim().to_string(); } }
    if let Some(v) = patch.ip { v.parse::<IpAddr>().map_err(|_| AppError::BadRequest("invalid IP address".into()))?; device.ip = v; }
    if let Some(v) = patch.port { device.port = v; }
    if let Some(v) = patch.protocol_version {
        let v = v.min(2);
        if device.protocol_version != v {
            device.protocol_version = v;
            device.key = None;
            device.supports_light = None;
            device.supports_quiet = None;
            device.supports_turbo = None;
            device.supports_air = None;
            device.supports_xfan = None;
            device.supports_health = None;
            device.supports_sleep = None;
        }
    }
    if let Some(v) = patch.key { device.key = v.filter(|x| !x.trim().is_empty()); }
    if let Some(v) = patch.enabled { device.enabled = v; }
    device.updated_at = Utc::now();
    state.db.save_device(&device)?;
    state.broadcast("device.updated", serde_json::to_value(&device)?);
    Ok(Json(device))
}

async fn delete_device(State(state): State<AppState>, Path(id): Path<String>) -> Result<StatusCode, AppError> {
    if state.db.get_device(&id)?.is_none() { return Err(AppError::NotFound(format!("device {id}"))); }
    if state.db.list_automations()?.iter().any(|item| {
        item.trigger_device_id.as_deref() == Some(id.as_str())
            || (item.action_group_id.is_none() && item.action_device_id == id)
    }) {
        return Err(AppError::BadRequest("device is used by an automation; remove or retarget that automation first".into()));
    }
    let removed_zone_ids: std::collections::HashSet<String> = state.db.list_zones()?.into_iter()
        .filter(|zone| zone.device_id == id)
        .map(|zone| zone.id)
        .collect();
    ensure_zone_removal_safe(&state, &removed_zone_ids)?;
    ensure_device_stopped_for_detach(&state, &id, "device.deleted").await?;
    if !state.db.delete_device(&id)? { return Err(AppError::NotFound(format!("device {id}"))); }
    remove_zone_ids_from_groups(&state, &removed_zone_ids)?;
    state.log("info", "device.deleted", "Device deleted", json!({"device_id": id}));
    state.broadcast("device.deleted", json!({"id": id}));
    Ok(StatusCode::NO_CONTENT)
}

async fn bind_device(State(state): State<AppState>, Path(id): Path<String>) -> Result<Json<Device>, AppError> {
    let _device_guard = state.lock_device_operation(&id).await;
    let mut device = state.db.get_device(&id)?.ok_or_else(|| AppError::NotFound(format!("device {id}")))?;
    if device.simulated { return Ok(Json(device)); }
    let bound = state.gree.bind(&device).await.map_err(|e| AppError::Device(e.to_string()))?;
    device.key = Some(bound.key);
    device.protocol_version = bound.protocol_version;
    device.communication_failures = 0;
    device.online = true;
    device.last_seen = Some(Utc::now());
    device.last_error = None;
    device.updated_at = Utc::now();
    state.db.save_device(&device)?;
    state.log("info", "device.bound", &format!("Bound {}", device.name), json!({"device_id": id}));
    Ok(Json(device))
}

async fn poll_device(State(state): State<AppState>, Path(id): Path<String>) -> Result<Json<Device>, AppError> {
    Ok(Json(engine::poll_one(&state, &id).await?))
}

async fn command_device(State(state): State<AppState>, Path(id): Path<String>, Json(command): Json<DeviceCommand>) -> Result<Json<Device>, AppError> {
    Ok(Json(engine::send_manual_command(&state, &id, command, "device.manual_control").await?))
}

async fn command_home_assistant_device(State(state): State<AppState>, Path(id): Path<String>, Json(command): Json<DeviceCommand>) -> Result<Json<Device>, AppError> {
    if state.db.list_zones()?.iter().any(|zone| zone.device_id == id && !zone.enabled) {
        return Err(AppError::BadRequest("device belongs to a disabled thermostat zone; use technical device control for manual operation".into()));
    }
    Ok(Json(engine::send_manual_command(&state, &id, command, "home_assistant.device_manual_control").await?))
}

#[derive(Debug, Deserialize)]
struct ZoneInput {
    name: String,
    device_id: String,
    #[serde(default = "yes")]
    enabled: bool,
    #[serde(default = "cool")]
    mode: String,
    #[serde(default = "yes")]
    inherit_house_mode: bool,
    #[serde(default = "setpoint")]
    setpoint: f64,
    #[serde(default = "cool_comfort")]
    cool_comfort_setpoint: f64,
    #[serde(default = "cool_sleep")]
    cool_sleep_setpoint: f64,
    #[serde(default = "cool_away")]
    cool_away_setpoint: f64,
    #[serde(default = "heat_comfort")]
    heat_comfort_setpoint: f64,
    #[serde(default = "heat_sleep")]
    heat_sleep_setpoint: f64,
    #[serde(default = "heat_away")]
    heat_away_setpoint: f64,
    #[serde(default = "hysteresis")]
    hysteresis: f64,
    #[serde(default = "cycle")]
    min_on_seconds: u64,
    #[serde(default = "cycle")]
    min_off_seconds: u64,
    #[serde(default = "min_adjust")]
    min_adjust_seconds: u64,
    #[serde(default = "standby_offset")]
    standby_offset_c: f64,
    #[serde(default = "yes")]
    smart_fan: bool,
    #[serde(default = "device_source")]
    sensor_source: String,
    #[serde(default)]
    ha_entity_id: Option<String>,
    #[serde(default = "external_sensor_weight")]
    external_sensor_weight: f64,
    #[serde(default = "max_sensor_difference")]
    max_sensor_difference: f64,
}
fn yes() -> bool { true }
fn cool() -> String { "cool".into() }
fn setpoint() -> f64 { 24.0 }
fn cool_comfort() -> f64 { 23.0 }
fn cool_sleep() -> f64 { 24.5 }
fn cool_away() -> f64 { 27.0 }
fn heat_comfort() -> f64 { 21.0 }
fn heat_sleep() -> f64 { 19.0 }
fn heat_away() -> f64 { 17.0 }
fn hysteresis() -> f64 { 0.6 }
fn cycle() -> u64 { 180 }
fn min_adjust() -> u64 { 120 }
fn standby_offset() -> f64 { 2.0 }
fn external_sensor_weight() -> f64 { 0.4 }
fn max_sensor_difference() -> f64 { 3.0 }
fn device_source() -> String { "device".into() }

impl ZoneInput {
    fn validate(&self) -> Result<(), AppError> {
        if self.name.trim().is_empty() { return Err(AppError::BadRequest("zone name is required".into())); }
        for value in [self.setpoint, self.cool_comfort_setpoint, self.cool_sleep_setpoint, self.cool_away_setpoint,
            self.heat_comfort_setpoint, self.heat_sleep_setpoint, self.heat_away_setpoint] {
            if !(8.0..=30.0).contains(&value) { return Err(AppError::BadRequest("zone temperatures must be between 8 and 30 C".into())); }
        }
        if !(0.1..=5.0).contains(&self.hysteresis) { return Err(AppError::BadRequest("hysteresis must be between 0.1 and 5 C".into())); }
        if !(0.5..=8.0).contains(&self.standby_offset_c) { return Err(AppError::BadRequest("standby offset must be between 0.5 and 8 C".into())); }
        if !matches!(self.mode.as_str(), "cool" | "heat") { return Err(AppError::BadRequest("zone mode must be cool or heat".into())); }
        if !matches!(self.sensor_source.as_str(), "device" | "home_assistant" | "combined") { return Err(AppError::BadRequest("unsupported sensor source".into())); }
        if !(0.0..=1.0).contains(&self.external_sensor_weight) { return Err(AppError::BadRequest("external sensor weight must be between 0 and 1".into())); }
        if !(0.1..=20.0).contains(&self.max_sensor_difference) { return Err(AppError::BadRequest("maximum sensor difference must be between 0.1 and 20 C".into())); }
        if matches!(self.sensor_source.as_str(), "home_assistant" | "combined") && self.ha_entity_id.as_deref().map(|value| value.trim()).unwrap_or("").is_empty() {
            return Err(AppError::BadRequest("a per-zone Home Assistant entity_id is required for external or combined temperature control".into()));
        }
        Ok(())
    }
    fn into_zone(self, id: String, created_at: chrono::DateTime<Utc>) -> Zone {
        Zone {
            id, name: self.name.trim().into(), device_id: self.device_id, enabled: self.enabled,
            mode: self.mode, inherit_house_mode: self.inherit_house_mode, setpoint: self.setpoint, profile_version: 1,
            cool_comfort_setpoint: self.cool_comfort_setpoint, cool_sleep_setpoint: self.cool_sleep_setpoint,
            cool_away_setpoint: self.cool_away_setpoint, heat_comfort_setpoint: self.heat_comfort_setpoint,
            heat_sleep_setpoint: self.heat_sleep_setpoint, heat_away_setpoint: self.heat_away_setpoint,
            hysteresis: self.hysteresis, min_on_seconds: self.min_on_seconds, min_off_seconds: self.min_off_seconds,
            min_adjust_seconds: self.min_adjust_seconds, standby_offset_c: self.standby_offset_c, smart_fan: self.smart_fan,
            sensor_source: self.sensor_source, ha_entity_id: self.ha_entity_id.filter(|v| !v.trim().is_empty()),
            external_sensor_weight: self.external_sensor_weight, max_sensor_difference: self.max_sensor_difference,
            device_temperature: None, external_temperature: None, current_temperature: None, control_temperature_source: "device".into(),
            active_preset: "comfort".into(), manual_preset: None, manual_setpoint: None, manual_override_until: None, local_thermostat_power: None, local_thermostat_resume_at: None,
            device_manual_override: false, device_manual_override_since: None, device_manual_override_until: None, device_manual_override_fields: Vec::new(), device_manual_override_baseline: None,
            effective_mode: String::new(), effective_setpoint: None, device_setpoint: None,
            demand: false, demand_since: None, target_alerted_at: None, last_action_at: None,
            created_at, updated_at: Utc::now(),
        }
    }
}

fn validate_zone_device_assignment(state: &AppState, device_id: &str, current_zone_id: Option<&str>) -> Result<(), AppError> {
    if state.db.list_zones()?.iter().any(|zone| zone.device_id == device_id && current_zone_id != Some(zone.id.as_str())) {
        return Err(AppError::BadRequest("a device can belong to only one thermostat zone".into()));
    }
    Ok(())
}

async fn list_zones(State(state): State<AppState>) -> Result<Json<Vec<Zone>>, AppError> { Ok(Json(state.db.list_zones()?)) }
async fn get_zone(State(state): State<AppState>, Path(id): Path<String>) -> Result<Json<Zone>, AppError> {
    state.db.get_zone(&id)?.map(Json).ok_or_else(|| AppError::NotFound(format!("zone {id}")))
}
async fn create_zone(State(state): State<AppState>, Json(input): Json<ZoneInput>) -> Result<(StatusCode, Json<Zone>), AppError> {
    input.validate()?;
    if state.db.get_device(&input.device_id)?.is_none() { return Err(AppError::BadRequest("zone device does not exist".into())); }
    validate_zone_device_assignment(&state, &input.device_id, None)?;
    let mut zone = input.into_zone(Uuid::new_v4().to_string(), Utc::now());
    let settings = state.settings.read().await.clone();
    canonicalize_zone_ha_entity(&mut zone, &settings);
    state.db.save_zone(&zone)?;
    state.broadcast("zone.created", serde_json::to_value(&zone)?);
    Ok((StatusCode::CREATED, Json(zone)))
}
async fn update_zone(State(state): State<AppState>, Path(id): Path<String>, Json(input): Json<ZoneInput>) -> Result<Json<Zone>, AppError> {
    input.validate()?;
    let existing = state.db.get_zone(&id)?.ok_or_else(|| AppError::NotFound(format!("zone {id}")))?;
    if state.db.get_device(&input.device_id)?.is_none() { return Err(AppError::BadRequest("zone device does not exist".into())); }
    validate_zone_device_assignment(&state, &input.device_id, Some(&id))?;
    let device_changed = existing.device_id != input.device_id;
    let mut zone = input.into_zone(id, existing.created_at);
    if !device_changed {
        zone.device_temperature = existing.device_temperature;
        zone.external_temperature = existing.external_temperature;
        zone.current_temperature = existing.current_temperature;
        zone.control_temperature_source = existing.control_temperature_source;
        zone.active_preset = existing.active_preset;
        zone.manual_preset = existing.manual_preset;
        zone.manual_setpoint = existing.manual_setpoint;
        zone.manual_override_until = existing.manual_override_until;
        zone.local_thermostat_power = existing.local_thermostat_power;
        zone.local_thermostat_resume_at = existing.local_thermostat_resume_at;
        zone.device_manual_override = existing.device_manual_override;
        zone.device_manual_override_since = existing.device_manual_override_since;
        zone.device_manual_override_until = existing.device_manual_override_until;
        zone.device_manual_override_fields = existing.device_manual_override_fields;
        zone.device_manual_override_baseline = existing.device_manual_override_baseline;
        zone.effective_mode = existing.effective_mode;
        zone.effective_setpoint = existing.effective_setpoint;
        zone.device_setpoint = existing.device_setpoint;
        zone.demand = existing.demand;
        zone.demand_since = existing.demand_since;
        zone.target_alerted_at = existing.target_alerted_at;
        zone.last_action_at = existing.last_action_at;
    } else {
        // A new physical unit starts with a clean ownership/runtime state. Never transfer
        // demand, sensor cache or remote-control takeover from the previous device.
        ensure_device_stopped_for_detach(&state, &existing.device_id, "zone.device_reassigned").await?;
    }
    let settings = state.settings.read().await.clone();
    canonicalize_zone_ha_entity(&mut zone, &settings);
    let power_off_device = !device_changed && existing.enabled && !zone.enabled;
    state.db.save_zone(&zone)?;
    state.broadcast("zone.updated", serde_json::to_value(&zone)?);
    if power_off_device {
        power_off_zone_device(&state, &zone, "zone.disabled").await;
    }
    Ok(Json(zone))
}

async fn apply_zone_control_patch(state: &AppState, id: &str, patch: ZoneControlPatch) -> Result<Zone, AppError> {
    let mut zone = state.db.get_zone(id)?.ok_or_else(|| AppError::NotFound(format!("zone {id}")))?;
    let was_enabled = zone.enabled;
    let schedules = state.db.list_schedules()?;
    let resume_device_takeover = patch.clear_device_manual_override.unwrap_or(false);
    let resume_local_thermostat = patch.clear_local_thermostat_override.unwrap_or(false);
    // Any thermostat action takes ownership back from a physical/pilot takeover. Local power
    // is a thermostat state of its own and must never be recorded as device manual control.
    let resume_device_automation = resume_device_takeover
        || patch.power.is_some() || patch.setpoint.is_some() || patch.mode.is_some()
        || patch.preset.is_some() || patch.enabled.is_some();

    if resume_local_thermostat {
        engine::reset_local_thermostat_override(&mut zone);
    }
    if let Some(power) = patch.power {
        zone.local_thermostat_power = Some(power);
        zone.local_thermostat_resume_at = if power {
            None
        } else {
            Some(Utc::now() + chrono::Duration::minutes(engine::LOCAL_THERMOSTAT_RESUME_DELAY_MINUTES))
        };
        if power { zone.enabled = true; }
        // A manually started local thermostat keeps an already selected target/profile until
        // it is switched off and the delayed hand-back completes, Auto is selected, or the
        // user explicitly resumes automation.
        if power && (zone.manual_preset.is_some() || zone.manual_setpoint.is_some()) {
            zone.manual_override_until = None;
        }
    }
    if let Some(value) = patch.setpoint {
        if !(8.0..=30.0).contains(&value) { return Err(AppError::BadRequest("zone setpoint must be between 8 and 30 C".into())); }
        let value = (value * 2.0).round() / 2.0;
        zone.setpoint = value;
        zone.manual_setpoint = Some(value);
        zone.effective_setpoint = Some(value);
        zone.manual_override_until = if zone.local_thermostat_power == Some(true) {
            None
        } else {
            engine::next_schedule_boundary_utc(&zone.id, &schedules, chrono::Local::now())
        };
    }
    if let Some(value) = patch.mode.as_deref() {
        match value {
            "house" | "auto" => zone.inherit_house_mode = true,
            "cool" | "heat" => {
                zone.inherit_house_mode = false;
                zone.mode = value.to_string();
            }
            _ => return Err(AppError::BadRequest("zone mode must be house, cool or heat".into())),
        }
    }
    if let Some(value) = patch.preset.as_deref() {
        match value {
            "auto" => {
                zone.manual_preset = None;
                zone.manual_setpoint = None;
                zone.manual_override_until = None;
            }
            "comfort" | "sleep" | "away" | "custom" => {
                zone.manual_preset = Some(value.to_string());
                zone.manual_setpoint = None;
                zone.manual_override_until = if zone.local_thermostat_power == Some(true) {
                    None
                } else {
                    engine::next_schedule_boundary_utc(&zone.id, &schedules, chrono::Local::now())
                };
            }
            _ => return Err(AppError::BadRequest("unsupported zone preset".into())),
        }
    }
    if patch.clear_override.unwrap_or(false) {
        zone.manual_preset = None;
        zone.manual_setpoint = None;
        zone.manual_override_until = None;
    }
    if let Some(value) = patch.enabled {
        zone.enabled = value;
        if !value { engine::reset_local_thermostat_override(&mut zone); }
    }
    let device_override_cleared = if resume_device_automation { engine::reset_device_manual_override(&mut zone) } else { false };
    let house_mode = state.settings.read().await.house_mode.clone();
    engine::refresh_zone_runtime_target(&mut zone, &schedules, &house_mode);
    zone.updated_at = Utc::now();
    state.db.save_zone(&zone)?;
    state.broadcast("zone.updated", serde_json::to_value(&zone)?);
    if was_enabled && !zone.enabled {
        power_off_zone_device(state, &zone, "zone.quick_disabled").await;
    } else if patch.power == Some(false) {
        if let Err(err) = engine::send_command(
            state,
            &zone.device_id,
            DeviceCommand { power: Some(false), ..Default::default() },
        ).await {
            state.log("error", "zone.local_power_error", &err.to_string(), json!({
                "zone_id": zone.id, "device_id": zone.device_id, "power": false
            }));
        }
        state.wake_zone_control();
    } else {
        state.wake_zone_control();
    }
    state.log("info", "zone.quick_control", &format!("Quick control updated for {}", zone.name), json!({
        "zone_id": zone.id, "setpoint": zone.setpoint, "manual_setpoint": zone.manual_setpoint, "mode": zone.mode,
        "inherit_house_mode": zone.inherit_house_mode, "preset": zone.manual_preset,
        "override_until": zone.manual_override_until, "enabled": zone.enabled,
        "local_thermostat_power": zone.local_thermostat_power,
        "local_thermostat_resume_at": zone.local_thermostat_resume_at,
        "device_manual_override_cleared": device_override_cleared
    }));
    Ok(zone)
}

async fn update_zone_control(State(state): State<AppState>, Path(id): Path<String>, Json(patch): Json<ZoneControlPatch>) -> Result<Json<Zone>, AppError> {
    Ok(Json(apply_zone_control_patch(&state, &id, patch).await?))
}



async fn ensure_device_stopped_for_detach(state: &AppState, device_id: &str, source: &str) -> Result<(), AppError> {
    let Some(device) = state.db.get_device(device_id)? else { return Ok(()); };
    if !device.enabled {
        return Err(AppError::BadRequest("cannot safely detach a technically disabled device; enable it so the controller can confirm it is powered off first".into()));
    }
    // Force one OFF transition even when the cached state already says OFF. A remote change
    // may not have been polled yet and detaching must not leave a running unit without owner.
    engine::force_power_off_device(state, device_id).await?;
    state.log("info", "zone.detach_power_off", &format!("Powered off {} before detaching thermostat ownership", device.name), json!({
        "device_id": device.id, "source": source
    }));
    Ok(())
}

async fn power_off_zone_device(state: &AppState, zone: &Zone, source: &str) {
    let Ok(Some(device)) = state.db.get_device(&zone.device_id) else { return; };
    if !device.enabled { return; }
    if let Err(err) = engine::force_power_off_device(state, &device.id).await {
        state.log("error", "zone.disable_power_error", &err.to_string(), json!({
            "zone_id": zone.id,
            "device_id": device.id,
            "device_name": device.name,
            "source": source,
        }));
    }
}

#[derive(Debug, Deserialize)]
struct GroupInput {
    name: String,
    #[serde(default)]
    zone_ids: Vec<String>,
    #[serde(default)]
    power_enabled: Option<bool>,
}

fn normalize_group_zone_ids(zone_ids: Vec<String>) -> Vec<String> {
    let mut values: Vec<String> = zone_ids.into_iter()
        .map(|value| value.trim().to_string())
        .filter(|value| !value.is_empty())
        .collect();
    values.sort();
    values.dedup();
    values
}

fn validate_group_input(state: &AppState, input: &GroupInput) -> Result<Vec<String>, AppError> {
    if input.name.trim().is_empty() {
        return Err(AppError::BadRequest("group name is required".into()));
    }
    let zone_ids = normalize_group_zone_ids(input.zone_ids.clone());
    if zone_ids.is_empty() {
        return Err(AppError::BadRequest("group must contain at least one zone".into()));
    }
    for zone_id in &zone_ids {
        if state.db.get_zone(zone_id)?.is_none() {
            return Err(AppError::BadRequest(format!("group references missing zone {zone_id}")));
        }
    }
    Ok(zone_ids)
}

async fn list_groups(State(state): State<AppState>) -> Result<Json<Vec<ClimateGroup>>, AppError> {
    Ok(Json(state.db.list_groups()?))
}

async fn get_group(State(state): State<AppState>, Path(id): Path<String>) -> Result<Json<ClimateGroup>, AppError> {
    state.db.get_group(&id)?.map(Json).ok_or_else(|| AppError::NotFound(format!("group {id}")))
}

async fn create_group(State(state): State<AppState>, Json(input): Json<GroupInput>) -> Result<(StatusCode, Json<ClimateGroup>), AppError> {
    let zone_ids = validate_group_input(&state, &input)?;
    let now = Utc::now();
    let group = ClimateGroup {
        id: Uuid::new_v4().to_string(),
        name: input.name.trim().to_string(),
        zone_ids,
        power_enabled: input.power_enabled.unwrap_or(true),
        created_at: now,
        updated_at: now,
    };
    state.db.save_group(&group)?;
    state.broadcast("group.created", serde_json::to_value(&group)?);
    Ok((StatusCode::CREATED, Json(group)))
}

async fn update_group(State(state): State<AppState>, Path(id): Path<String>, Json(input): Json<GroupInput>) -> Result<Json<ClimateGroup>, AppError> {
    let existing = state.db.get_group(&id)?.ok_or_else(|| AppError::NotFound(format!("group {id}")))?;
    let zone_ids = validate_group_input(&state, &input)?;
    let group = ClimateGroup {
        id,
        name: input.name.trim().to_string(),
        zone_ids,
        power_enabled: input.power_enabled.unwrap_or(existing.power_enabled),
        created_at: existing.created_at,
        updated_at: Utc::now(),
    };
    state.db.save_group(&group)?;
    state.broadcast("group.updated", serde_json::to_value(&group)?);
    Ok(Json(group))
}

async fn delete_group(State(state): State<AppState>, Path(id): Path<String>) -> Result<StatusCode, AppError> {
    if state.db.list_automations()?.iter().any(|item| item.action_group_id.as_deref() == Some(id.as_str())) {
        return Err(AppError::BadRequest("group is used by an automation; remove or retarget that automation first".into()));
    }
    if !state.db.delete_group(&id)? { return Err(AppError::NotFound(format!("group {id}"))); }
    state.broadcast("group.deleted", json!({"id": id}));
    Ok(StatusCode::NO_CONTENT)
}

fn ensure_zone_removal_safe(state: &AppState, zone_ids: &std::collections::HashSet<String>) -> Result<(), AppError> {
    if zone_ids.is_empty() { return Ok(()); }
    let automated_groups: std::collections::HashSet<String> = state.db.list_automations()?.into_iter()
        .filter_map(|item| item.action_group_id)
        .collect();
    for group in state.db.list_groups()? {
        let remaining = group.zone_ids.iter().filter(|zone_id| !zone_ids.contains(*zone_id)).count();
        if remaining == 0 && group.zone_ids.iter().any(|zone_id| zone_ids.contains(zone_id)) && automated_groups.contains(&group.id) {
            return Err(AppError::BadRequest(format!("cannot remove the last zone from group '{}' while an automation targets that group", group.name)));
        }
    }
    Ok(())
}

fn remove_zone_ids_from_groups(state: &AppState, zone_ids: &std::collections::HashSet<String>) -> Result<(), AppError> {
    if zone_ids.is_empty() { return Ok(()); }
    for mut group in state.db.list_groups()? {
        let before = group.zone_ids.len();
        group.zone_ids.retain(|zone_id| !zone_ids.contains(zone_id));
        if group.zone_ids.len() == before { continue; }
        if group.zone_ids.is_empty() {
            state.db.delete_group(&group.id)?;
            state.broadcast("group.deleted", json!({"id": group.id}));
            continue;
        }
        group.updated_at = Utc::now();
        state.db.save_group(&group)?;
        state.broadcast("group.updated", serde_json::to_value(&group)?);
    }
    Ok(())
}

async fn update_group_control(State(state): State<AppState>, Path(id): Path<String>, Json(patch): Json<GroupControlPatch>) -> Result<Json<Value>, AppError> {
    Ok(Json(engine::control_group(&state, &id, patch, "group.quick_control").await?))
}

fn home_assistant_group_mode(zones: &[&Zone]) -> String {
    let mut value: Option<&str> = None;
    for zone in zones {
        let current = if zone.inherit_house_mode { "house" } else { zone.mode.as_str() };
        if !matches!(current, "house" | "cool" | "heat") {
            return "mixed".into();
        }
        if let Some(previous) = value {
            if previous != current { return "mixed".into(); }
        } else {
            value = Some(current);
        }
    }
    value.unwrap_or("mixed").to_string()
}

fn home_assistant_group_preset(zones: &[&Zone]) -> String {
    let mut value: Option<&str> = None;
    for zone in zones {
        let current = zone.manual_preset.as_deref().unwrap_or("auto");
        if !matches!(current, "auto" | "comfort" | "sleep" | "away") {
            return "mixed".into();
        }
        if let Some(previous) = value {
            if previous != current { return "mixed".into(); }
        } else {
            value = Some(current);
        }
    }
    value.unwrap_or("mixed").to_string()
}

async fn list_home_assistant_groups(State(state): State<AppState>) -> Result<Json<Vec<Value>>, AppError> {
    let groups = state.db.list_groups()?;
    let zones = state.db.list_zones()?;
    let devices = state.db.list_devices()?;
    let plan = engine::build_control_plan(&state).await?;
    let settings = state.settings.read().await.clone();
    let mut output = Vec::with_capacity(groups.len());

    for group in groups {
        let members = zones.iter()
            .filter(|zone| group.zone_ids.iter().any(|zone_id| zone_id == &zone.id))
            .collect::<Vec<_>>();
        let planned_members = plan.zones.iter()
            .filter(|zone| group.zone_ids.iter().any(|zone_id| zone_id == &zone.zone_id))
            .collect::<Vec<_>>();

        let zone_names = members.iter().map(|zone| zone.name.clone()).collect::<Vec<_>>();
        let member_device_ids = members.iter().map(|zone| zone.device_id.as_str()).collect::<std::collections::HashSet<_>>();
        let online_devices = devices.iter()
            .filter(|device| member_device_ids.contains(device.id.as_str()) && device.online)
            .count();
        let current_temperatures = planned_members.iter()
            .filter_map(|zone| zone.current_temperature)
            .collect::<Vec<_>>();
        let current_temperature = if current_temperatures.is_empty() {
            None
        } else {
            Some(current_temperatures.iter().sum::<f64>() / current_temperatures.len() as f64)
        };
        let mut next_events = Vec::new();
        for zone in &planned_members {
            for event in &zone.next_events {
                let mut event = event.clone();
                event.label = format!("{}: {}", zone.zone_name, event.label);
                next_events.push(event);
            }
        }
        next_events.sort_by_key(|event| event.at);
        next_events.truncate(8);
        let member_states = planned_members.iter().map(|zone| json!({
            "zone_id": zone.zone_id,
            "zone_name": zone.zone_name,
            "device_id": zone.device_id,
            "device_name": zone.device_name,
            "enabled": zone.enabled,
            "effective_enabled": zone.effective_enabled,
            "mode": zone.mode,
            "configured_mode": zone.configured_mode,
            "inherit_house_mode": zone.inherit_house_mode,
            "preset": zone.preset,
            "current_temperature": zone.current_temperature,
            "target_temperature": zone.target_temperature,
            "demand": zone.demand,
            "control_source": zone.control_source,
            "current_schedule": zone.current_schedule_name,
            "local_thermostat_power": zone.local_thermostat_power,
            "local_thermostat_resume_at": zone.local_thermostat_resume_at,
            "device_manual_override": zone.device_manual_override,
            "device_manual_override_until": zone.device_manual_override_until,
        })).collect::<Vec<_>>();

        output.push(json!({
            "id": group.id,
            "name": group.name,
            "zone_ids": group.zone_ids,
            "zone_names": zone_names,
            "power_enabled": group.power_enabled,
            "effective_power": settings.house_power_enabled && group.power_enabled,
            "mode": home_assistant_group_mode(&members),
            "preset": home_assistant_group_preset(&members),
            "house_mode": settings.house_mode,
            "zone_count": members.len(),
            "enabled_zones": members.iter().filter(|zone| zone.enabled).count(),
            "active_zones": planned_members.iter().filter(|zone| zone.effective_enabled).count(),
            "demanding_zones": planned_members.iter().filter(|zone| zone.demand).count(),
            "device_count": member_device_ids.len(),
            "online_devices": online_devices,
            "current_temperature": current_temperature,
            "members": member_states,
            "next_events": next_events,
        }));
    }

    Ok(Json(output))
}

async fn update_home_assistant_group_control(
    State(state): State<AppState>,
    Path(id): Path<String>,
    Json(patch): Json<GroupControlPatch>,
) -> Result<Json<Value>, AppError> {
    Ok(Json(engine::control_group(&state, &id, patch, "home_assistant.group_control").await?))
}

#[derive(Debug, Deserialize)]
struct HouseControlPatch { mode: String }

fn set_all_groups_power(state: &AppState, power: bool) -> Result<(), AppError> {
    for mut group in state.db.list_groups()? {
        if group.power_enabled == power { continue; }
        group.power_enabled = power;
        group.updated_at = Utc::now();
        state.db.save_group(&group)?;
        state.broadcast("group.updated", serde_json::to_value(&group)?);
    }
    Ok(())
}

fn clear_all_local_thermostat_overrides(state: &AppState) -> Result<usize, AppError> {
    let mut cleared = 0;
    for mut zone in state.db.list_zones()? {
        if zone.local_thermostat_power.is_none() && zone.local_thermostat_resume_at.is_none() { continue; }
        engine::reset_local_thermostat_override(&mut zone);
        zone.updated_at = Utc::now();
        state.db.save_zone(&zone)?;
        state.broadcast("zone.updated", serde_json::to_value(&zone)?);
        cleared += 1;
    }
    Ok(cleared)
}

async fn command_all_enabled_devices_power(state: &AppState, power: bool, source: &str) -> Result<Vec<Value>, AppError> {
    let mut failed = Vec::new();
    let enabled_zone_devices: std::collections::HashSet<String> = if power {
        state.db.list_zones()?.into_iter()
            .filter(|zone| zone.enabled && !zone.device_manual_override && zone.local_thermostat_power != Some(false))
            .map(|zone| zone.device_id)
            .collect()
    } else {
        std::collections::HashSet::new()
    };
    for device in state.db.list_devices()? {
        if !device.enabled { continue; }
        // Whole-house ON only operates thermostat-managed, enabled zones. Devices with
        // a disabled zone (or no zone at all) remain manual/technical Devices controls.
        if power && !enabled_zone_devices.contains(&device.id) { continue; }
        // Do not trust the pre-loop power snapshot for deciding whether to send. The engine
        // reloads state under the per-device lock and turns an already-matching command into
        // a no-op. This closes the polling/command race without extra UDP frames.
        let result = if power {
            engine::send_command(state, &device.id, DeviceCommand { power: Some(true), ..Default::default() }).await
        } else {
            engine::force_house_power_off_device(state, &device.id, source).await
        };
        if let Err(err) = result {
            state.log("error", "house.power_all_error", &err.to_string(), json!({
                "device_id": device.id,
                "device_name": device.name,
                "power": power,
                "source": source,
            }));
            failed.push(json!({
                "device_id": device.id,
                "device_name": device.name,
                "error": err.to_string(),
            }));
        }
    }
    Ok(failed)
}

async fn update_house_control(State(state): State<AppState>, Json(input): Json<HouseControlPatch>) -> Result<Json<Value>, AppError> {
    if !matches!(input.mode.as_str(), "cool" | "heat" | "off") {
        return Err(AppError::BadRequest("house mode must be cool, heat or off".into()));
    }
    let mode = input.mode;
    let activate_all = mode != "off";
    let payload = {
        let mut settings = state.settings.write().await;
        settings.house_mode = mode.clone();
        // Choosing a real whole-house operating mode is an explicit request to run the
        // house climate. It therefore clears a previous global power-off. "off" keeps
        // its separate meaning: do not control, without changing master power.
        if activate_all { settings.house_power_enabled = true; }
        state.db.save_runtime_settings(&settings)?;
        public_settings(&settings)
    };
    state.broadcast("settings.updated", payload.clone());
    if activate_all {
        set_all_groups_power(&state, true)?;
        let failed = command_all_enabled_devices_power(&state, true, "house_mode").await?;
        if !failed.is_empty() {
            state.log("warn", "house.mode_power_partial", "House mode enabled master power, but some devices could not be powered on", json!({
                "mode": mode,
                "failed": failed.len(),
            }));
        }
    }
    state.log("info", "house.mode", &format!("House mode set to {}", mode), json!({"mode": mode, "master_power_enabled": activate_all}));
    Ok(Json(payload))
}

#[derive(Debug, Deserialize)]
struct HousePowerPatch { power: bool }

async fn update_house_power(State(state): State<AppState>, Json(input): Json<HousePowerPatch>) -> Result<Json<Value>, AppError> {
    // Whole-house power is independent from the thermostat mode. Publish/persist the master
    // first so the regulator becomes passive before the one-shot OFF cascade starts.
    {
        let mut settings = state.settings.write().await;
        if settings.house_power_enabled != input.power {
            settings.house_power_enabled = input.power;
            state.db.save_runtime_settings(&settings)?;
            let payload = public_settings(&settings);
            state.broadcast("settings.updated", payload);
        }
    }

    // Global power is a true cascade across group gates. OFF clears the current takeover
    // markers once, then each enabled device is re-cleared atomically with its OFF command.
    // A later pilot action is therefore not erased by subsequent controller cycles.
    set_all_groups_power(&state, input.power)?;
    if !input.power {
        engine::clear_all_device_manual_overrides(&state, "house_power_off")?;
        clear_all_local_thermostat_overrides(&state)?;
    }
    let failed = command_all_enabled_devices_power(&state, input.power, "house_power").await?;

    let devices = state.db.list_devices()?;
    let groups = state.db.list_groups()?;
    let settings = state.settings.read().await;
    let settings_payload = public_settings(&settings);
    drop(settings);
    state.log("info", "house.power_all", if input.power { "Whole-house power enabled; all enabled thermostat zones powered on" } else { "Whole-house power disabled; all groups and enabled devices powered off" }, json!({
        "power": input.power,
        "failed": failed.len(),
    }));
    Ok(Json(json!({
        "power": input.power,
        "devices": devices,
        "groups": groups,
        "settings": settings_payload,
        "failed": failed,
    })))
}

#[derive(Debug, Deserialize)]
struct HousePresetPatch { preset: String }

async fn update_house_preset(State(state): State<AppState>, Json(input): Json<HousePresetPatch>) -> Result<Json<Value>, AppError> {
    if !matches!(input.preset.as_str(), "auto" | "comfort" | "sleep" | "away") {
        return Err(AppError::BadRequest("house preset must be auto, comfort, sleep or away".into()));
    }

    // A whole-house profile is also an explicit whole-house activation. This mirrors
    // selecting cooling/heating and makes the separate master-power control intuitive.
    let settings_payload = {
        let mut settings = state.settings.write().await;
        settings.house_power_enabled = true;
        state.db.save_runtime_settings(&settings)?;
        public_settings(&settings)
    };
    state.broadcast("settings.updated", settings_payload.clone());
    set_all_groups_power(&state, true)?;

    let schedules = state.db.list_schedules()?;
    let mut zones = state.db.list_zones()?;
    for zone in &mut zones {
        if input.preset == "auto" {
            zone.manual_preset = None;
            zone.manual_setpoint = None;
            zone.manual_override_until = None;
        } else {
            zone.manual_preset = Some(input.preset.clone());
            zone.manual_setpoint = None;
            zone.manual_override_until = engine::next_schedule_boundary_utc(&zone.id, &schedules, chrono::Local::now());
        }
        zone.updated_at = Utc::now();
        state.db.save_zone(zone)?;
        state.broadcast("zone.updated", serde_json::to_value(&*zone)?);
    }

    let failed = command_all_enabled_devices_power(&state, true, "house_preset").await?;
    state.wake_zone_control();
    let devices = state.db.list_devices()?;
    state.log("info", "house.preset", &format!("House preset set to {}", input.preset), json!({
        "preset": input.preset,
        "master_power_enabled": true,
        "failed": failed.len(),
    }));
    Ok(Json(json!({
        "preset": input.preset,
        "zones": zones,
        "devices": devices,
        "settings": settings_payload,
        "failed": failed,
    })))
}

#[derive(Debug, Deserialize)]
struct ScheduleTemplateRequest { template: String }

async fn apply_schedule_template(State(state): State<AppState>, Path(id): Path<String>, Json(input): Json<ScheduleTemplateRequest>) -> Result<Json<Value>, AppError> {
    let zone = state.db.get_zone(&id)?.ok_or_else(|| AppError::NotFound(format!("zone {id}")))?;
    let mut items: Vec<Schedule> = Vec::new();
    let mut add = |name: &str, days: Vec<u32>, start: &str, end: &str, preset: &str| {
        items.push(Schedule {
            id: Uuid::new_v4().to_string(), zone_id: id.clone(), name: name.into(), enabled: true,
            weekdays: days, start_time: start.into(), end_time: end.into(), preset: preset.into(),
            setpoint: zone.setpoint, created_at: Utc::now(), updated_at: Utc::now(),
        });
    };
    let all = vec![1,2,3,4,5,6,7];
    match input.template.as_str() {
        "family" => {
            add("Comfort", all.clone(), "06:30", "22:30", "comfort");
            add("Sleep", all, "22:30", "06:30", "sleep");
        }
        "child" => {
            add("Comfort", all.clone(), "06:30", "20:30", "comfort");
            add("Sleep", all, "20:30", "06:30", "sleep");
        }
        "bedroom" => {
            add("Comfort", all.clone(), "06:30", "22:00", "comfort");
            add("Sleep", all, "22:00", "06:30", "sleep");
        }
        "workday" => {
            let weekdays = vec![1,2,3,4,5];
            let weekend = vec![6,7];
            add("Morning", weekdays.clone(), "06:30", "08:00", "comfort");
            add("Away", weekdays.clone(), "08:00", "16:00", "away");
            add("Evening", weekdays.clone(), "16:00", "22:30", "comfort");
            add("Sleep", weekdays, "22:30", "06:30", "sleep");
            add("Weekend", weekend, "08:00", "23:00", "comfort");
            // Saturday can sleep until the Sunday weekend block starts at 08:00.
            add("Saturday sleep", vec![6], "23:00", "08:00", "sleep");
            // Sunday must hand over at 06:30 so it never overlaps Monday morning.
            add("Sunday sleep", vec![7], "23:00", "06:30", "sleep");
        }
        "always" => add("Comfort", all, "00:00", "00:00", "comfort"),
        _ => return Err(AppError::BadRequest("unknown schedule template".into())),
    }
    validate_schedule_set(&items)?;
    state.db.replace_schedules_for_zone(&id, &items)?;
    refresh_zone_override_boundary(&state, &id)?;
    state.broadcast("schedule.template_applied", json!({"zone_id": id, "template": input.template, "count": items.len()}));
    Ok(Json(json!({"zone": zone, "schedules": items})))
}

async fn delete_zone(State(state): State<AppState>, Path(id): Path<String>) -> Result<StatusCode, AppError> {
    let zone = state.db.get_zone(&id)?.ok_or_else(|| AppError::NotFound(format!("zone {id}")))?;
    let mut removed = std::collections::HashSet::new();
    removed.insert(id.clone());
    ensure_zone_removal_safe(&state, &removed)?;
    ensure_device_stopped_for_detach(&state, &zone.device_id, "zone.deleted").await?;
    if !state.db.delete_zone(&id)? { return Err(AppError::NotFound(format!("zone {id}"))); }
    remove_zone_ids_from_groups(&state, &removed)?;
    state.broadcast("zone.deleted", json!({"id": id}));
    Ok(StatusCode::NO_CONTENT)
}

#[derive(Debug, Deserialize)]
struct ScheduleInput {
    zone_id: String,
    name: String,
    #[serde(default = "yes")]
    enabled: bool,
    weekdays: Vec<u32>,
    start_time: String,
    end_time: String,
    #[serde(default = "schedule_preset")]
    preset: String,
    setpoint: f64,
}
fn schedule_preset() -> String { "custom".into() }
impl ScheduleInput {
    fn validate(&self) -> Result<(), AppError> {
        if self.name.trim().is_empty() { return Err(AppError::BadRequest("schedule name is required".into())); }
        if self.weekdays.is_empty() || self.weekdays.iter().any(|v| !(1..=7).contains(v)) { return Err(AppError::BadRequest("weekdays must contain numbers 1..7".into())); }
        chrono::NaiveTime::parse_from_str(&self.start_time, "%H:%M").map_err(|_| AppError::BadRequest("invalid start time".into()))?;
        chrono::NaiveTime::parse_from_str(&self.end_time, "%H:%M").map_err(|_| AppError::BadRequest("invalid end time".into()))?;
        if !matches!(self.preset.as_str(), "comfort" | "sleep" | "away" | "custom") { return Err(AppError::BadRequest("unsupported schedule preset".into())); }
        if self.preset == "custom" && !(8.0..=30.0).contains(&self.setpoint) { return Err(AppError::BadRequest("schedule setpoint must be between 8 and 30 C".into())); }
        Ok(())
    }
    fn into_schedule(self, id: String, created_at: chrono::DateTime<Utc>) -> Schedule {
        Schedule { id, zone_id: self.zone_id, name: self.name.trim().into(), enabled: self.enabled,
            weekdays: self.weekdays, start_time: self.start_time, end_time: self.end_time,
            preset: self.preset, setpoint: self.setpoint, created_at, updated_at: Utc::now() }
    }
}
fn validate_schedule_set(items: &[Schedule]) -> Result<(), AppError> {
    for (index, item) in items.iter().enumerate() {
        for other in items.iter().skip(index + 1) {
            if engine::schedules_overlap(item, other) {
                return Err(AppError::BadRequest(format!("schedule '{}' overlaps with '{}' for the same zone", item.name, other.name)));
            }
        }
    }
    Ok(())
}

fn validate_schedule_conflicts(state: &AppState, item: &Schedule, exclude_id: Option<&str>) -> Result<(), AppError> {
    for existing in state.db.list_schedules()? {
        if exclude_id == Some(existing.id.as_str()) { continue; }
        if engine::schedules_overlap(item, &existing) {
            return Err(AppError::BadRequest(format!("schedule overlaps with '{}'", existing.name)));
        }
    }
    Ok(())
}

fn refresh_zone_override_boundary(state: &AppState, zone_id: &str) -> Result<(), AppError> {
    let Some(mut zone) = state.db.get_zone(zone_id)? else { return Ok(()); };
    if zone.manual_preset.is_none() && zone.manual_setpoint.is_none() { return Ok(()); }
    let schedules = state.db.list_schedules()?;
    zone.manual_override_until = engine::next_schedule_boundary_utc(&zone.id, &schedules, chrono::Local::now());
    zone.updated_at = Utc::now();
    state.db.save_zone(&zone)?;
    state.broadcast("zone.updated", serde_json::to_value(&zone)?);
    Ok(())
}

async fn list_schedules(State(state): State<AppState>) -> Result<Json<Vec<Schedule>>, AppError> { Ok(Json(state.db.list_schedules()?)) }
async fn get_schedule(State(state): State<AppState>, Path(id): Path<String>) -> Result<Json<Schedule>, AppError> {
    state.db.get_schedule(&id)?.map(Json).ok_or_else(|| AppError::NotFound(format!("schedule {id}")))
}
async fn create_schedule(State(state): State<AppState>, Json(input): Json<ScheduleInput>) -> Result<(StatusCode, Json<Schedule>), AppError> {
    input.validate()?;
    if state.db.get_zone(&input.zone_id)?.is_none() { return Err(AppError::BadRequest("schedule zone does not exist".into())); }
    let item = input.into_schedule(Uuid::new_v4().to_string(), Utc::now());
    validate_schedule_conflicts(&state, &item, None)?;
    state.db.save_schedule(&item)?;
    refresh_zone_override_boundary(&state, &item.zone_id)?;
    state.broadcast("schedule.created", serde_json::to_value(&item)?);
    Ok((StatusCode::CREATED, Json(item)))
}
async fn update_schedule(State(state): State<AppState>, Path(id): Path<String>, Json(input): Json<ScheduleInput>) -> Result<Json<Schedule>, AppError> {
    input.validate()?;
    let existing = state.db.get_schedule(&id)?.ok_or_else(|| AppError::NotFound(format!("schedule {id}")))?;
    if state.db.get_zone(&input.zone_id)?.is_none() { return Err(AppError::BadRequest("schedule zone does not exist".into())); }
    let old_zone_id = existing.zone_id.clone();
    let item = input.into_schedule(id.clone(), existing.created_at);
    validate_schedule_conflicts(&state, &item, Some(&id))?;
    state.db.save_schedule(&item)?;
    refresh_zone_override_boundary(&state, &old_zone_id)?;
    if item.zone_id != old_zone_id { refresh_zone_override_boundary(&state, &item.zone_id)?; }
    state.broadcast("schedule.updated", serde_json::to_value(&item)?);
    Ok(Json(item))
}
async fn delete_schedule(State(state): State<AppState>, Path(id): Path<String>) -> Result<StatusCode, AppError> {
    let existing = state.db.get_schedule(&id)?.ok_or_else(|| AppError::NotFound(format!("schedule {id}")))?;
    if !state.db.delete_schedule(&id)? { return Err(AppError::NotFound(format!("schedule {id}"))); }
    refresh_zone_override_boundary(&state, &existing.zone_id)?;
    state.broadcast("schedule.deleted", json!({"id": id}));
    Ok(StatusCode::NO_CONTENT)
}

#[derive(Debug, Deserialize)]
struct AutomationInput {
    name: String,
    #[serde(default = "yes")]
    enabled: bool,
    trigger_kind: String,
    #[serde(default)]
    trigger_device_id: Option<String>,
    #[serde(default)]
    threshold: Option<f64>,
    #[serde(default)]
    at_time: Option<String>,
    #[serde(default)]
    action_device_id: String,
    #[serde(default)]
    action_group_id: Option<String>,
    #[serde(default)]
    action_preset: Option<String>,
    #[serde(default)]
    action: DeviceCommand,
    #[serde(default = "automation_cooldown")]
    cooldown_seconds: u64,
}
fn automation_cooldown() -> u64 { 300 }
impl AutomationInput {
    fn validate(&self) -> Result<(), AppError> {
        if self.name.trim().is_empty() { return Err(AppError::BadRequest("automation name is required".into())); }
        match self.trigger_kind.as_str() {
            "temperature_above" | "temperature_below" => {
                if self.trigger_device_id.as_deref().unwrap_or_default().is_empty() || self.threshold.is_none() {
                    return Err(AppError::BadRequest("temperature trigger needs device and threshold".into()));
                }
            }
            "time" => {
                let at = self.at_time.as_deref().ok_or_else(|| AppError::BadRequest("time trigger needs at_time".into()))?;
                chrono::NaiveTime::parse_from_str(at, "%H:%M").map_err(|_| AppError::BadRequest("invalid automation time".into()))?;
            }
            _ => return Err(AppError::BadRequest("unsupported automation trigger".into())),
        }
        let action_group_id = self.action_group_id.as_deref().map(str::trim).filter(|value| !value.is_empty());
        if action_group_id.is_none() && self.action_device_id.trim().is_empty() {
            return Err(AppError::BadRequest("automation action needs a device or group".into()));
        }
        if let Some(preset) = self.action_preset.as_deref().map(str::trim).filter(|value| !value.is_empty()) {
            if action_group_id.is_none() {
                return Err(AppError::BadRequest("automation preset actions require a group target".into()));
            }
            if !matches!(preset, "auto" | "comfort" | "sleep" | "away") {
                return Err(AppError::BadRequest("unsupported group automation preset".into()));
            }
        }
        if action_group_id.is_some() {
            if let Some(mode) = self.action.mode.as_deref() {
                if !matches!(mode, "auto" | "house" | "cool" | "heat") {
                    return Err(AppError::BadRequest("group automation mode must be house, cool or heat".into()));
                }
            }
            if self.action.target_temperature.is_some()
                || self.action.fan_speed.is_some()
                || self.action.swing_vertical.is_some()
                || self.action.swing_horizontal.is_some()
                || self.action.quiet.is_some()
                || self.action.turbo.is_some()
                || self.action.light.is_some()
                || self.action.air.is_some()
                || self.action.xfan.is_some()
                || self.action.health.is_some()
                || self.action.sleep.is_some()
            {
                return Err(AppError::BadRequest("group automations support only power, heat/cool/house mode and a group preset".into()));
            }
            if self.action.power.is_none() && self.action.mode.is_none() && self.action_preset.as_deref().map(str::trim).filter(|v| !v.is_empty()).is_none() {
                return Err(AppError::BadRequest("group automation action cannot be empty".into()));
            }
        } else {
            engine::validate_command(&self.action)?;
            if self.action.is_empty() {
                return Err(AppError::BadRequest("automation action cannot be empty".into()));
            }
        }
        Ok(())
    }
    fn into_automation(self, id: String, created_at: chrono::DateTime<Utc>, last_fired_at: Option<chrono::DateTime<Utc>>) -> Automation {
        Automation { id, name: self.name.trim().into(), enabled: self.enabled,
            trigger_kind: self.trigger_kind, trigger_device_id: self.trigger_device_id.map(|value| value.trim().to_string()).filter(|value| !value.is_empty()),
            threshold: self.threshold, at_time: self.at_time, action_device_id: self.action_device_id.trim().to_string(),
            action_group_id: self.action_group_id.map(|value| value.trim().to_string()).filter(|value| !value.is_empty()),
            action_preset: self.action_preset.map(|value| value.trim().to_string()).filter(|value| !value.is_empty()),
            action: self.action, cooldown_seconds: self.cooldown_seconds.max(30), last_fired_at,
            created_at, updated_at: Utc::now() }
    }
}
fn validate_automation_references(state: &AppState, input: &AutomationInput) -> Result<(), AppError> {
    if matches!(input.trigger_kind.as_str(), "temperature_above" | "temperature_below") {
        let trigger_id = input.trigger_device_id.as_deref().map(str::trim).unwrap_or_default();
        if state.db.get_device(trigger_id)?.is_none() {
            return Err(AppError::BadRequest("automation trigger device does not exist".into()));
        }
    }
    if let Some(group_id) = input.action_group_id.as_deref().map(str::trim).filter(|value| !value.is_empty()) {
        if state.db.get_group(group_id)?.is_none() {
            return Err(AppError::BadRequest("automation action group does not exist".into()));
        }
    } else if state.db.get_device(input.action_device_id.trim())?.is_none() {
        return Err(AppError::BadRequest("automation action device does not exist".into()));
    }
    Ok(())
}

async fn list_automations(State(state): State<AppState>) -> Result<Json<Vec<Automation>>, AppError> { Ok(Json(state.db.list_automations()?)) }
async fn get_automation(State(state): State<AppState>, Path(id): Path<String>) -> Result<Json<Automation>, AppError> {
    state.db.get_automation(&id)?.map(Json).ok_or_else(|| AppError::NotFound(format!("automation {id}")))
}
async fn create_automation(State(state): State<AppState>, Json(input): Json<AutomationInput>) -> Result<(StatusCode, Json<Automation>), AppError> {
    input.validate()?;
    validate_automation_references(&state, &input)?;
    let item = input.into_automation(Uuid::new_v4().to_string(), Utc::now(), None);
    state.db.save_automation(&item)?;
    state.broadcast("automation.created", serde_json::to_value(&item)?);
    Ok((StatusCode::CREATED, Json(item)))
}
async fn update_automation(State(state): State<AppState>, Path(id): Path<String>, Json(input): Json<AutomationInput>) -> Result<Json<Automation>, AppError> {
    input.validate()?;
    let existing = state.db.get_automation(&id)?.ok_or_else(|| AppError::NotFound(format!("automation {id}")))?;
    validate_automation_references(&state, &input)?;
    let item = input.into_automation(id, existing.created_at, existing.last_fired_at);
    state.db.save_automation(&item)?;
    state.broadcast("automation.updated", serde_json::to_value(&item)?);
    Ok(Json(item))
}
async fn delete_automation(State(state): State<AppState>, Path(id): Path<String>) -> Result<StatusCode, AppError> {
    if !state.db.delete_automation(&id)? { return Err(AppError::NotFound(format!("automation {id}"))); }
    state.broadcast("automation.deleted", json!({"id": id}));
    Ok(StatusCode::NO_CONTENT)
}

#[derive(Debug, Deserialize)]
struct ReadingsQuery { device_id: Option<String>, hours: Option<i64>, limit: Option<u32> }
async fn readings(State(state): State<AppState>, Query(query): Query<ReadingsQuery>) -> Result<Json<Value>, AppError> {
    let hours = query.hours.unwrap_or(24).clamp(1, 24 * 3650);
    let values = state.db.list_readings(query.device_id.as_deref(), Utc::now() - ChronoDuration::hours(hours), query.limit.unwrap_or(1500))?;
    Ok(Json(json!({"readings": values})))
}

#[derive(Debug, Deserialize)]
struct HistoryQuery {
    scope: Option<String>,
    zone_id: Option<String>,
    device_id: Option<String>,
    entity_id: Option<String>,
    hours: Option<i64>,
    limit: Option<u32>,
}

fn history_bucket_seconds(hours: i64) -> i64 {
    match hours {
        1..=6 => 30,
        7..=24 => 120,
        25..=168 => 600,
        169..=720 => 1800,
        721..=2160 => 7200,
        2161..=8760 => 21600,
        _ => 86400,
    }
}

fn fallback_zone_rows(zone: &Zone, device: &Device, readings: Vec<Reading>) -> Vec<ZoneReading> {
    readings.into_iter().map(|reading| ZoneReading {
        id: reading.id,
        zone_id: zone.id.clone(),
        device_id: zone.device_id.clone(),
        timestamp: reading.timestamp,
        gree_temperature: reading.indoor_temperature,
        external_temperature: None,
        control_temperature: reading.indoor_temperature,
        target_temperature: Some(reading.target_temperature),
        device_setpoint: Some(reading.target_temperature),
        outdoor_temperature: reading.outdoor_temperature,
        power: reading.power,
        mode: device.mode.clone(),
        fan_speed: device.fan_speed,
        demand: false,
        control_source: "gree_history_fallback".into(),
        active_preset: "history".into(),
    }).collect()
}

fn zone_history_with_fallback(
    state: &AppState,
    zone_id: Option<&str>,
    since: chrono::DateTime<Utc>,
    bucket_seconds: i64,
    limit: u32,
) -> Result<Vec<ZoneReading>, AppError> {
    let mut values = state.db.list_zone_history(zone_id, since.clone(), bucket_seconds, limit)?;
    if let Some(zone_id) = zone_id {
        if values.is_empty() {
            let zone = state.db.get_zone(zone_id)?.ok_or_else(|| AppError::NotFound(format!("zone {zone_id}")))?;
            if let Some(device) = state.db.get_device(&zone.device_id)? {
                let rows = state.db.list_device_history(Some(&zone.device_id), since.clone(), bucket_seconds, limit)?;
                values = fallback_zone_rows(&zone, &device, rows);
            }
        }
        return Ok(values);
    }

    let existing: std::collections::HashSet<String> = values.iter().map(|row| row.zone_id.clone()).collect();
    for zone in state.db.list_zones()? {
        if existing.contains(&zone.id) { continue; }
        let Some(device) = state.db.get_device(&zone.device_id)? else { continue; };
        let rows = state.db.list_device_history(Some(&zone.device_id), since.clone(), bucket_seconds, limit)?;
        values.extend(fallback_zone_rows(&zone, &device, rows));
    }
    values.sort_by(|left, right| left.timestamp.cmp(&right.timestamp));
    if values.len() > limit as usize {
        let keep_from = values.len() - limit as usize;
        values.drain(0..keep_from);
    }
    Ok(values)
}

fn sensor_history_with_fallback(
    state: &AppState,
    since: chrono::DateTime<Utc>,
    bucket_seconds: i64,
    limit: u32,
    outdoor_entity: &str,
) -> Result<Vec<HaReading>, AppError> {
    let mut values = state.db.list_ha_history(None, since.clone(), bucket_seconds, limit)?;
    let mut existing: std::collections::HashSet<String> = values.iter().map(|row| row.entity_id.clone()).collect();
    for zone in state.db.list_zones()? {
        let Some(entity_id) = zone.ha_entity_id.as_deref().filter(|value| !value.trim().is_empty()) else { continue; };
        if existing.contains(entity_id) { continue; }
        let rows = state.db.list_zone_history(Some(&zone.id), since.clone(), bucket_seconds, limit)?;
        let mut added = false;
        for row in rows {
            if let Some(temperature) = row.external_temperature {
                values.push(HaReading { id: row.id, entity_id: entity_id.to_string(), zone_id: Some(zone.id.clone()), kind: "room".into(), timestamp: row.timestamp, temperature });
                added = true;
            }
        }
        if added { existing.insert(entity_id.to_string()); }
    }
    let outdoor_entity = outdoor_entity.trim();
    if !outdoor_entity.is_empty() && !existing.contains(outdoor_entity) {
        for zone in state.db.list_zones()? {
            let rows = state.db.list_zone_history(Some(&zone.id), since.clone(), bucket_seconds, limit)?;
            let mut added = false;
            for row in rows {
                if let Some(temperature) = row.outdoor_temperature {
                    values.push(HaReading { id: row.id, entity_id: outdoor_entity.to_string(), zone_id: None, kind: "outdoor".into(), timestamp: row.timestamp, temperature });
                    added = true;
                }
            }
            if added { break; }
        }
    }
    values.sort_by(|left, right| left.timestamp.cmp(&right.timestamp));
    if values.len() > limit as usize {
        let keep_from = values.len() - limit as usize;
        values.drain(0..keep_from);
    }
    Ok(values)
}

async fn combined_device_history(
    state: &AppState,
    device_id: Option<&str>,
    since: chrono::DateTime<Utc>,
    bucket_seconds: i64,
    limit: u32,
) -> Result<(Vec<Reading>, String, Option<String>), AppError> {
    let influx = state.settings.read().await.influxdb.clone();
    let cutoff = Utc::now() - ChronoDuration::days(influx.history_threshold_days.max(1) as i64);
    if !influx.enabled || since >= cutoff {
        return Ok((state.db.list_device_history(device_id, since, bucket_seconds, limit)?, "sqlite".into(), None));
    }
    let mut warning = None;
    let mut values = match influxdb::query_devices(&state.http, &influx, device_id, since, cutoff, bucket_seconds, limit).await {
        Ok(rows) => rows,
        Err(err) => {
            warning = Some(err.to_string());
            state.log("warn", "influx.query_error", "InfluxDB device history query failed", json!({"error": err.to_string()}));
            state.db.list_device_history(device_id, since, bucket_seconds, limit)?
        }
    };
    if warning.is_none() {
        values.extend(state.db.list_device_history(device_id, cutoff, bucket_seconds, limit)?);
    }
    values.sort_by_key(|row| row.timestamp);
    trim_history(&mut values, limit);
    let source = if warning.is_some() { "sqlite_fallback" } else { "influx+sqlite" };
    Ok((values, source.into(), warning))
}

async fn combined_zone_history(
    state: &AppState,
    zone_id: Option<&str>,
    since: chrono::DateTime<Utc>,
    bucket_seconds: i64,
    limit: u32,
) -> Result<(Vec<ZoneReading>, String, Option<String>), AppError> {
    let influx = state.settings.read().await.influxdb.clone();
    let cutoff = Utc::now() - ChronoDuration::days(influx.history_threshold_days.max(1) as i64);
    if !influx.enabled || since >= cutoff {
        return Ok((zone_history_with_fallback(state, zone_id, since, bucket_seconds, limit)?, "sqlite".into(), None));
    }
    let mut warning = None;
    let mut values = match influxdb::query_zones(&state.http, &influx, zone_id, since, cutoff, bucket_seconds, limit).await {
        Ok(rows) => rows,
        Err(err) => {
            warning = Some(err.to_string());
            state.log("warn", "influx.query_error", "InfluxDB zone history query failed", json!({"error": err.to_string()}));
            zone_history_with_fallback(state, zone_id, since, bucket_seconds, limit)?
        }
    };
    if warning.is_none() {
        values.extend(zone_history_with_fallback(state, zone_id, cutoff, bucket_seconds, limit)?);
    }
    values.sort_by_key(|row| row.timestamp);
    trim_history(&mut values, limit);
    let source = if warning.is_some() { "sqlite_fallback" } else { "influx+sqlite" };
    Ok((values, source.into(), warning))
}

async fn combined_sensor_history(
    state: &AppState,
    entity_id: Option<&str>,
    since: chrono::DateTime<Utc>,
    bucket_seconds: i64,
    limit: u32,
    outdoor_entity: &str,
) -> Result<(Vec<HaReading>, String, Option<String>), AppError> {
    let influx = state.settings.read().await.influxdb.clone();
    let cutoff = Utc::now() - ChronoDuration::days(influx.history_threshold_days.max(1) as i64);
    let local = |start| -> Result<Vec<HaReading>, AppError> {
        if entity_id.is_some() { Ok(state.db.list_ha_history(entity_id, start, bucket_seconds, limit)?) }
        else { sensor_history_with_fallback(state, start, bucket_seconds, limit, outdoor_entity) }
    };
    if !influx.enabled || since >= cutoff {
        return Ok((local(since)?, "sqlite".into(), None));
    }
    let mut warning = None;
    let mut values = match influxdb::query_ha(&state.http, &influx, entity_id, since, cutoff, bucket_seconds, limit).await {
        Ok(rows) => rows,
        Err(err) => {
            warning = Some(err.to_string());
            state.log("warn", "influx.query_error", "InfluxDB HA history query failed", json!({"error": err.to_string()}));
            local(since)?
        }
    };
    if warning.is_none() {
        values.extend(local(cutoff)?);
    }
    values.sort_by_key(|row| row.timestamp);
    trim_history(&mut values, limit);
    let source = if warning.is_some() { "sqlite_fallback" } else { "influx+sqlite" };
    Ok((values, source.into(), warning))
}

fn trim_history<T>(values: &mut Vec<T>, limit: u32) {
    if values.len() > limit as usize {
        let keep_from = values.len() - limit as usize;
        values.drain(0..keep_from);
    }
}

async fn history(State(state): State<AppState>, Query(query): Query<HistoryQuery>) -> Result<Json<Value>, AppError> {
    let hours = query.hours.unwrap_or(24).clamp(1, 24 * 3650);
    let since = Utc::now() - ChronoDuration::hours(hours);
    let bucket_seconds = history_bucket_seconds(hours);
    let limit = query.limit.unwrap_or(12_000).clamp(1, 20_000);
    let scope = query.scope.as_deref().unwrap_or("zones");
    let outdoor_entity = state.settings.read().await.home_assistant.outdoor_entity_id.clone();
    let (device_count, zone_count, ha_count) = state.db.history_counts()?;

    match scope {
        "devices" => {
            let device_id = query.device_id.as_deref().filter(|value| !value.is_empty() && *value != "all");
            let (readings, storage, warning) = combined_device_history(&state, device_id, since, bucket_seconds, limit).await?;
            Ok(Json(json!({
                "scope": "devices", "readings": readings, "bucket_seconds": bucket_seconds,
                "storage": storage, "storage_warning": warning,
                "counts": {"devices": device_count, "zones": zone_count, "ha": ha_count}
            })))
        }
        "sensors" => {
            let entity_id = query.entity_id.as_deref().filter(|value| !value.is_empty() && *value != "all");
            let (readings, storage, warning) = combined_sensor_history(&state, entity_id, since, bucket_seconds, limit, &outdoor_entity).await?;
            Ok(Json(json!({
                "scope": "sensors", "readings": readings, "bucket_seconds": bucket_seconds,
                "storage": storage, "storage_warning": warning,
                "counts": {"devices": device_count, "zones": zone_count, "ha": ha_count}
            })))
        }
        "overview" => {
            let (zones, zone_storage, zone_warning) = combined_zone_history(&state, None, since, bucket_seconds, limit).await?;
            let (devices, device_storage, device_warning) = combined_device_history(&state, None, since, bucket_seconds, limit).await?;
            let (sensors, sensor_storage, sensor_warning) = combined_sensor_history(&state, None, since, bucket_seconds, limit, &outdoor_entity).await?;
            let storage_warning = [zone_warning, device_warning, sensor_warning]
                .into_iter()
                .flatten()
                .collect::<Vec<_>>();
            Ok(Json(json!({
                "scope": "overview", "bucket_seconds": bucket_seconds,
                "zones": zones, "devices": devices, "sensors": sensors,
                "storage": {"zones": zone_storage, "devices": device_storage, "sensors": sensor_storage},
                "storage_warning": storage_warning,
                "counts": {"devices": device_count, "zones": zone_count, "ha": ha_count}
            })))
        }
        "zones" | "zone" => {
            let zone_id = query.zone_id.as_deref().filter(|value| !value.is_empty() && *value != "all");
            if let Some(zone_id) = zone_id {
                if state.db.get_zone(zone_id)?.is_none() {
                    return Err(AppError::NotFound(format!("zone {zone_id}")));
                }
            }
            let (readings, storage, warning) = combined_zone_history(&state, zone_id, since, bucket_seconds, limit).await?;
            Ok(Json(json!({
                "scope": "zones", "readings": readings, "bucket_seconds": bucket_seconds,
                "storage": storage, "storage_warning": warning,
                "counts": {"devices": device_count, "zones": zone_count, "ha": ha_count}
            })))
        }
        _ => Err(AppError::BadRequest("history scope must be overview, zones, devices or sensors".into())),
    }
}

async fn control_plan(State(state): State<AppState>) -> Result<Json<Value>, AppError> {
    Ok(Json(serde_json::to_value(engine::build_control_plan(&state).await?)?))
}

#[derive(Debug, Deserialize)]
struct EventsQuery { limit: Option<u32> }
async fn events(State(state): State<AppState>, Query(query): Query<EventsQuery>) -> Result<Json<Value>, AppError> {
    Ok(Json(json!({"events": state.db.list_events(query.limit.unwrap_or(100))?})))
}

#[derive(Debug, Deserialize)]
struct EventRetentionInput { days: u32 }

async fn get_event_retention(State(state): State<AppState>) -> Json<Value> {
    let days = state.settings.read().await.event_log_retention_days;
    Json(json!({"days": days}))
}

async fn update_event_retention(State(state): State<AppState>, Json(input): Json<EventRetentionInput>) -> Result<Json<Value>, AppError> {
    let mut settings = state.settings.write().await;
    settings.event_log_retention_days = input.days.clamp(1, 3650);
    state.db.save_runtime_settings(&settings)?;
    let days = settings.event_log_retention_days;
    drop(settings);
    let removed = state.db.prune_events(days as i64)?;
    state.log("info", "events.retention_updated", "Event log retention updated", json!({"days": days, "removed": removed}));
    let public = { let settings = state.settings.read().await; public_settings(&*settings) };
    state.broadcast("settings.updated", public);
    Ok(Json(json!({"days": days, "removed": removed})))
}

async fn get_settings(State(state): State<AppState>) -> Json<Value> {
    let settings = state.settings.read().await;
    Json(public_settings(&*settings))
}

async fn update_settings(State(state): State<AppState>, Json(mut input): Json<RuntimeSettings>) -> Result<Json<Value>, AppError> {
    let old = state.settings.read().await.clone();
    input.poll_interval_seconds = input.poll_interval_seconds.clamp(2, 3600);
    input.zone_interval_seconds = input.zone_interval_seconds.clamp(2, 3600);
    input.discovery_timeout_ms = input.discovery_timeout_ms.clamp(300, 30_000);
    if !matches!(input.house_mode.as_str(), "cool" | "heat" | "off") { return Err(AppError::BadRequest("house mode must be cool, heat or off".into())); }
    if input.control_strategy != "setpoint" { input.control_strategy = "setpoint".into(); }
    if !(input.discovery_broadcast.eq_ignore_ascii_case("auto")
        || input.discovery_broadcast.to_ascii_lowercase().starts_with("auto:")) {
        input.discovery_broadcast.parse::<std::net::SocketAddr>()
            .map_err(|_| AppError::BadRequest("invalid discovery broadcast address".into()))?;
    }
    if input.controller_id.trim().is_empty() { input.controller_id = old.controller_id; }
    if input.home_assistant.token.trim().is_empty() { input.home_assistant.token = old.home_assistant.token; }
    if input.notifications.pushover_app_token.trim().is_empty() { input.notifications.pushover_app_token = old.notifications.pushover_app_token; }
    if input.notifications.pushover_user_key.trim().is_empty() { input.notifications.pushover_user_key = old.notifications.pushover_user_key; }
    if input.notifications.slack_webhook_url.trim().is_empty() { input.notifications.slack_webhook_url = old.notifications.slack_webhook_url; }
    if input.notifications.discord_webhook_url.trim().is_empty() { input.notifications.discord_webhook_url = old.notifications.discord_webhook_url; }
    input.notifications.cooldown_seconds = input.notifications.cooldown_seconds.clamp(30, 86_400);
    input.notifications.communication_failure_threshold = input.notifications.communication_failure_threshold.clamp(2, 100);
    input.notifications.target_timeout_minutes = input.notifications.target_timeout_minutes.clamp(5, 24 * 60);
    if !matches!(input.notifications.mode.as_str(), "problems" | "important") { return Err(AppError::BadRequest("notification mode must be problems or important".into())); }
    if !matches!(input.notifications.provider.as_str(), "pushover" | "slack" | "discord") { return Err(AppError::BadRequest("unsupported notification provider".into())); }
    input.history_retention_days = input.history_retention_days.clamp(1, 3650);
    input.event_log_retention_days = input.event_log_retention_days.clamp(1, 3650);
    normalize_sensor_aliases(&mut input);
    canonicalize_home_assistant_entities(&mut input);
    validate_night_mode(&mut input)?;
    input.influxdb.history_threshold_days = input.influxdb.history_threshold_days.clamp(1, 3650);
    if input.influxdb.token.trim().is_empty() { input.influxdb.token = old.influxdb.token; }
    if input.influxdb.password.trim().is_empty() { input.influxdb.password = old.influxdb.password; }
    influxdb::validate(&input.influxdb).map_err(|err| AppError::BadRequest(err.to_string()))?;
    if !input.home_assistant.url.trim().is_empty() {
        let parsed = url::Url::parse(&input.home_assistant.url).map_err(|_| AppError::BadRequest("invalid Home Assistant URL".into()))?;
        if !matches!(parsed.scheme(), "http" | "https") { return Err(AppError::BadRequest("Home Assistant URL must use http or https".into())); }
    }
    state.db.save_runtime_settings(&input)?;
    canonicalize_saved_zone_entities(&state, &input)?;
    state.debug_gree_frames.store(input.debug.gree_frames, Ordering::Relaxed);
    *state.settings.write().await = input.clone();
    state.log("info", "settings.updated", "Settings updated", json!({}));
    state.broadcast("settings.updated", public_settings(&input));
    Ok(Json(public_settings(&input)))
}

fn normalize_sensor_aliases(settings: &mut RuntimeSettings) {
    settings.home_assistant.sensor_aliases = settings.home_assistant.sensor_aliases
        .iter()
        .filter_map(|(entity, alias)| {
            let entity = entity.trim();
            let alias = alias.trim();
            if entity.is_empty() || alias.is_empty() { return None; }
            Some((entity.chars().take(160).collect::<String>(), alias.chars().take(80).collect::<String>()))
        })
        .collect();
}

fn canonicalize_home_assistant_entities(settings: &mut RuntimeSettings) {
    let default_entity = settings.home_assistant.default_entity_id.clone();
    if let Some(entity_id) = home_assistant::resolve_entity_id(&settings.home_assistant, Some(&default_entity)) {
        settings.home_assistant.default_entity_id = entity_id;
    }
    let outdoor_entity = settings.home_assistant.outdoor_entity_id.clone();
    if !outdoor_entity.trim().is_empty() {
        if let Some(entity_id) = home_assistant::resolve_entity_id(&settings.home_assistant, Some(&outdoor_entity)) {
            settings.home_assistant.outdoor_entity_id = entity_id;
        }
    }
}

fn canonicalize_zone_ha_entity(zone: &mut Zone, settings: &RuntimeSettings) {
    let Some(configured) = zone.ha_entity_id.clone() else { return; };
    zone.ha_entity_id = home_assistant::resolve_entity_id(&settings.home_assistant, Some(&configured));
}

fn canonicalize_saved_zone_entities(state: &AppState, settings: &RuntimeSettings) -> Result<(), AppError> {
    for mut zone in state.db.list_zones()? {
        let previous = zone.ha_entity_id.clone();
        canonicalize_zone_ha_entity(&mut zone, settings);
        if zone.ha_entity_id != previous {
            zone.updated_at = Utc::now();
            state.db.save_zone(&zone)?;
            state.broadcast("zone.updated", serde_json::to_value(&zone)?);
        }
    }
    Ok(())
}

fn validate_night_mode(settings: &mut RuntimeSettings) -> Result<(), AppError> {
    NaiveTime::parse_from_str(&settings.night_mode.start_time, "%H:%M")
        .map_err(|_| AppError::BadRequest("night mode start time must use HH:MM".into()))?;
    NaiveTime::parse_from_str(&settings.night_mode.end_time, "%H:%M")
        .map_err(|_| AppError::BadRequest("night mode end time must use HH:MM".into()))?;
    settings.night_mode.max_fan_speed = settings.night_mode.max_fan_speed.clamp(1, 5);
    Ok(())
}

async fn export_settings(State(state): State<AppState>) -> Result<Json<ConfigurationExport>, AppError> {
    let settings = state.settings.read().await.clone();
    Ok(Json(state.db.export_configuration(settings)?))
}

fn validate_configuration_export(export: &ConfigurationExport) -> Result<(), AppError> {
    if export.format_version != 1 { return Err(AppError::BadRequest("unsupported configuration export version".into())); }
    influxdb::validate(&export.settings.influxdb).map_err(|err| AppError::BadRequest(err.to_string()))?;
    if !matches!(export.settings.house_mode.as_str(), "cool" | "heat" | "off") {
        return Err(AppError::BadRequest("import contains an invalid house mode".into()));
    }

    let devices: std::collections::HashSet<&str> = export.devices.iter().map(|item| item.id.as_str()).collect();
    let zones: std::collections::HashSet<&str> = export.zones.iter().map(|item| item.id.as_str()).collect();
    let schedules: std::collections::HashSet<&str> = export.schedules.iter().map(|item| item.id.as_str()).collect();
    let automations: std::collections::HashSet<&str> = export.automations.iter().map(|item| item.id.as_str()).collect();
    if devices.len() != export.devices.len() || zones.len() != export.zones.len()
        || schedules.len() != export.schedules.len() || automations.len() != export.automations.len()
        || devices.contains("") || zones.contains("") || schedules.contains("") || automations.contains("")
    {
        return Err(AppError::BadRequest("import contains duplicate or empty resource IDs".into()));
    }
    let device_macs: std::collections::HashSet<&str> = export.devices.iter().map(|item| item.mac.as_str()).collect();
    if device_macs.len() != export.devices.len() {
        return Err(AppError::BadRequest("import contains duplicate device MAC addresses".into()));
    }
    if export.zones.iter().any(|item| !devices.contains(item.device_id.as_str())) {
        return Err(AppError::BadRequest("import contains a zone referencing a missing device".into()));
    }
    let mut zone_devices = std::collections::HashSet::new();
    for zone in &export.zones {
        if !zone_devices.insert(zone.device_id.as_str()) {
            return Err(AppError::BadRequest("import assigns one device to more than one thermostat zone".into()));
        }
        if !matches!(zone.mode.as_str(), "cool" | "heat") {
            return Err(AppError::BadRequest("import contains an invalid zone mode".into()));
        }
        if !matches!(zone.sensor_source.as_str(), "device" | "home_assistant" | "combined") {
            return Err(AppError::BadRequest("import contains an invalid zone sensor source".into()));
        }
    }

    if export.schedules.iter().any(|item| !zones.contains(item.zone_id.as_str())) {
        return Err(AppError::BadRequest("import contains a schedule referencing a missing zone".into()));
    }
    for item in &export.schedules {
        if item.weekdays.is_empty() || item.weekdays.iter().any(|day| !(1..=7).contains(day)) {
            return Err(AppError::BadRequest("import contains invalid schedule weekdays".into()));
        }
        NaiveTime::parse_from_str(&item.start_time, "%H:%M").map_err(|_| AppError::BadRequest("import contains an invalid schedule start time".into()))?;
        NaiveTime::parse_from_str(&item.end_time, "%H:%M").map_err(|_| AppError::BadRequest("import contains an invalid schedule end time".into()))?;
        if !matches!(item.preset.as_str(), "comfort" | "sleep" | "away" | "custom") {
            return Err(AppError::BadRequest("import contains an invalid schedule preset".into()));
        }
        if item.preset == "custom" && !(8.0..=30.0).contains(&item.setpoint) {
            return Err(AppError::BadRequest("import contains an invalid schedule setpoint".into()));
        }
    }
    validate_schedule_set(&export.schedules)?;

    if export.groups.iter().any(|group| {
        let members: std::collections::HashSet<&str> = group.zone_ids.iter().map(String::as_str).collect();
        group.id.trim().is_empty() || group.zone_ids.is_empty() || members.len() != group.zone_ids.len()
            || group.zone_ids.iter().any(|zone_id| !zones.contains(zone_id.as_str()))
    }) {
        return Err(AppError::BadRequest("import contains an invalid group, duplicate members or a missing zone reference".into()));
    }
    let groups: std::collections::HashSet<&str> = export.groups.iter().map(|item| item.id.as_str()).collect();
    if groups.len() != export.groups.len() {
        return Err(AppError::BadRequest("import contains duplicate group IDs".into()));
    }

    for item in &export.automations {
        match item.trigger_kind.as_str() {
            "temperature_above" | "temperature_below" => {
                let Some(trigger_id) = item.trigger_device_id.as_deref() else {
                    return Err(AppError::BadRequest("import contains a temperature automation without a trigger device".into()));
                };
                if !devices.contains(trigger_id) || item.threshold.is_none() {
                    return Err(AppError::BadRequest("import contains an invalid temperature automation trigger".into()));
                }
            }
            "time" => {
                let at = item.at_time.as_deref().ok_or_else(|| AppError::BadRequest("import contains a time automation without at_time".into()))?;
                NaiveTime::parse_from_str(at, "%H:%M").map_err(|_| AppError::BadRequest("import contains an invalid automation time".into()))?;
            }
            _ => return Err(AppError::BadRequest("import contains an unsupported automation trigger".into())),
        }

        if let Some(group_id) = item.action_group_id.as_deref().filter(|value| !value.is_empty()) {
            if !groups.contains(group_id) {
                return Err(AppError::BadRequest("import contains an automation referencing a missing group".into()));
            }
            if let Some(mode) = item.action.mode.as_deref() {
                if !matches!(mode, "auto" | "house" | "cool" | "heat") {
                    return Err(AppError::BadRequest("import contains an invalid group automation mode".into()));
                }
            }
            if let Some(preset) = item.action_preset.as_deref() {
                if !matches!(preset, "auto" | "comfort" | "sleep" | "away") {
                    return Err(AppError::BadRequest("import contains an invalid group automation preset".into()));
                }
            }
            if item.action.target_temperature.is_some() || item.action.fan_speed.is_some()
                || item.action.swing_vertical.is_some() || item.action.swing_horizontal.is_some()
                || item.action.quiet.is_some() || item.action.turbo.is_some() || item.action.light.is_some()
                || item.action.air.is_some() || item.action.xfan.is_some() || item.action.health.is_some() || item.action.sleep.is_some()
            {
                return Err(AppError::BadRequest("import contains unsupported fields in a group automation".into()));
            }
            if item.action.power.is_none() && item.action.mode.is_none() && item.action_preset.as_deref().filter(|v| !v.is_empty()).is_none() {
                return Err(AppError::BadRequest("import contains an empty group automation action".into()));
            }
        } else {
            if !devices.contains(item.action_device_id.as_str()) {
                return Err(AppError::BadRequest("import contains an automation referencing a missing device".into()));
            }
            engine::validate_command(&item.action)?;
            if item.action.is_empty() {
                return Err(AppError::BadRequest("import contains an empty automation action".into()));
            }
        }
    }
    Ok(())
}

async fn import_settings(State(state): State<AppState>, Json(mut export): Json<ConfigurationExport>) -> Result<Json<Value>, AppError> {
    validate_configuration_export(&export)?;
    export.settings.history_retention_days = export.settings.history_retention_days.clamp(1, 3650);
    export.settings.event_log_retention_days = export.settings.event_log_retention_days.clamp(1, 3650);
    normalize_sensor_aliases(&mut export.settings);
    canonicalize_home_assistant_entities(&mut export.settings);
    for zone in &mut export.zones { canonicalize_zone_ha_entity(zone, &export.settings); }
    validate_night_mode(&mut export.settings)?;
    export.settings.influxdb.history_threshold_days = export.settings.influxdb.history_threshold_days.clamp(1, 3650);
    state.db.replace_configuration(&export)?;
    state.debug_gree_frames.store(export.settings.debug.gree_frames, Ordering::Relaxed);
    *state.settings.write().await = export.settings.clone();
    state.log("info", "settings.imported", "Application configuration imported", json!({"format_version": export.format_version}));
    state.broadcast("configuration.imported", json!({"at": Utc::now()}));
    Ok(Json(json!({"ok": true})))
}

async fn get_debug(State(state): State<AppState>) -> Json<DebugSettings> {
    Json(state.settings.read().await.debug.clone())
}

async fn update_debug(State(state): State<AppState>, Json(input): Json<DebugSettings>) -> Result<Json<DebugSettings>, AppError> {
    let mut settings = state.settings.write().await;
    settings.debug = input.clone();
    state.db.save_runtime_settings(&settings)?;
    state.debug_gree_frames.store(input.gree_frames, Ordering::Relaxed);
    state.broadcast("debug.settings", serde_json::to_value(&input)?);
    Ok(Json(input))
}

#[derive(Debug, Deserialize)]
struct CreateAccessTokenRequest {
    name: Option<String>,
}

async fn list_access_tokens(State(state): State<AppState>) -> Result<Json<Vec<ApiTokenInfo>>, AppError> {
    Ok(Json(state.db.list_api_tokens()?))
}

async fn create_access_token(
    State(state): State<AppState>,
    Json(input): Json<CreateAccessTokenRequest>,
) -> Result<(StatusCode, Json<Value>), AppError> {
    let name = input.name.unwrap_or_else(|| "Home Assistant".into()).trim().to_string();
    if name.is_empty() || name.len() > 80 {
        return Err(AppError::BadRequest("token name must contain 1 to 80 characters".into()));
    }

    let secret = generate_access_token();
    let item = ApiTokenInfo {
        id: Uuid::new_v4().to_string(),
        name,
        token_prefix: format!("{}...", secret.chars().take(24).collect::<String>()),
        created_at: Utc::now(),
    };
    state.db.save_api_token(&item, &hash_token(&secret))?;
    state.log(
        "info",
        "access_token.created",
        "Created a Home Assistant access token",
        json!({"token_id": item.id.clone(), "name": item.name.clone()}),
    );
    Ok((StatusCode::CREATED, Json(json!({"token": secret, "item": item}))))
}

async fn delete_access_token(State(state): State<AppState>, Path(id): Path<String>) -> Result<StatusCode, AppError> {
    if !state.db.delete_api_token(&id)? {
        return Err(AppError::NotFound(format!("access token {id}")));
    }
    state.log(
        "info",
        "access_token.revoked",
        "Revoked a Home Assistant access token",
        json!({"token_id": id}),
    );
    Ok(StatusCode::NO_CONTENT)
}

#[derive(Debug, Deserialize)]
struct HaTestRequest { entity_id: Option<String> }
async fn test_home_assistant(State(state): State<AppState>, Json(input): Json<HaTestRequest>) -> Result<Json<Value>, AppError> {
    let settings = state.settings.read().await.clone();
    let resolved_entity_id = home_assistant::resolve_entity_id(&settings.home_assistant, input.entity_id.as_deref());
    let temperature = home_assistant::read_temperature(&state.http, &settings.home_assistant, resolved_entity_id.as_deref())
        .await.map_err(|e| AppError::Device(e.to_string()))?;
    Ok(Json(json!({"ok": true, "temperature_c": temperature, "entity_id": resolved_entity_id})))
}

async fn test_notifications(State(state): State<AppState>, Json(mut input): Json<NotificationSettings>) -> Result<Json<Value>, AppError> {
    let old = state.settings.read().await.notifications.clone();
    if input.pushover_app_token.trim().is_empty() { input.pushover_app_token = old.pushover_app_token; }
    if input.pushover_user_key.trim().is_empty() { input.pushover_user_key = old.pushover_user_key; }
    if input.slack_webhook_url.trim().is_empty() { input.slack_webhook_url = old.slack_webhook_url; }
    if input.discord_webhook_url.trim().is_empty() { input.discord_webhook_url = old.discord_webhook_url; }
    notifications::test(&state, input).await.map_err(AppError::Device)?;
    Ok(Json(json!({"ok": true})))
}

async fn security_headers(request: Request, next: Next) -> Response {
    let is_api = request.uri().path().contains("/api/");
    let mut response = next.run(request).await;
    let headers = response.headers_mut();
    headers.insert(header::HeaderName::from_static("x-content-type-options"), HeaderValue::from_static("nosniff"));
    headers.insert(header::HeaderName::from_static("x-frame-options"), HeaderValue::from_static("SAMEORIGIN"));
    headers.insert(header::HeaderName::from_static("referrer-policy"), HeaderValue::from_static("same-origin"));
    headers.insert(header::HeaderName::from_static("content-security-policy"), HeaderValue::from_static("default-src 'self'; connect-src 'self' ws: wss:; img-src 'self' data:; style-src 'self' 'unsafe-inline'; script-src 'self'; base-uri 'self'; form-action 'self'; frame-ancestors 'self'; object-src 'none'"));
    headers.insert(header::HeaderName::from_static("permissions-policy"), HeaderValue::from_static("camera=(), microphone=(), geolocation=()"));
    if is_api { headers.insert(header::CACHE_CONTROL, HeaderValue::from_static("no-store")); }
    response
}

fn public_settings(settings: &RuntimeSettings) -> Value {
    json!({
        "controller_id": settings.controller_id,
        "simulator_enabled": settings.simulator_enabled,
        "poll_interval_seconds": settings.poll_interval_seconds,
        "zone_interval_seconds": settings.zone_interval_seconds,
        "discovery_timeout_ms": settings.discovery_timeout_ms,
        "discovery_broadcast": settings.discovery_broadcast,
        "house_mode": settings.house_mode,
        "house_power_enabled": settings.house_power_enabled,
        "control_strategy": settings.control_strategy,
        "outdoor_assist_enabled": settings.outdoor_assist_enabled,
        "history_retention_days": settings.history_retention_days,
        "history_compaction_enabled": settings.history_compaction_enabled,
        "event_log_retention_days": settings.event_log_retention_days,
        "suppress_device_beep": settings.suppress_device_beep,
        "debug": settings.debug,
        "night_mode": settings.night_mode,
        "notifications": {
            "enabled": settings.notifications.enabled,
            "mode": settings.notifications.mode,
            "provider": settings.notifications.provider,
            "pushover_app_token": "",
            "pushover_user_key": "",
            "pushover_configured": !settings.notifications.pushover_app_token.trim().is_empty() && !settings.notifications.pushover_user_key.trim().is_empty(),
            "slack_webhook_url": "",
            "slack_configured": !settings.notifications.slack_webhook_url.trim().is_empty(),
            "discord_webhook_url": "",
            "discord_configured": !settings.notifications.discord_webhook_url.trim().is_empty(),
            "cooldown_seconds": settings.notifications.cooldown_seconds,
            "communication_failure_threshold": settings.notifications.communication_failure_threshold,
            "target_timeout_minutes": settings.notifications.target_timeout_minutes,
        },
        "influxdb": {
            "enabled": settings.influxdb.enabled,
            "version": settings.influxdb.version,
            "url": settings.influxdb.url,
            "database": settings.influxdb.database,
            "username": settings.influxdb.username,
            "password": "",
            "password_configured": !settings.influxdb.password.trim().is_empty(),
            "org": settings.influxdb.org,
            "bucket": settings.influxdb.bucket,
            "token": "",
            "token_configured": !settings.influxdb.token.trim().is_empty(),
            "history_threshold_days": settings.influxdb.history_threshold_days,
        },
        "home_assistant": {
            "url": settings.home_assistant.url,
            "token": "",
            "token_configured": !settings.home_assistant.token.trim().is_empty(),
            "default_entity_id": settings.home_assistant.default_entity_id,
            "outdoor_entity_id": settings.home_assistant.outdoor_entity_id,
            "allow_invalid_tls": settings.home_assistant.allow_invalid_tls,
            "sensor_aliases": settings.home_assistant.sensor_aliases,
        }
    })
}

#[derive(Debug, Deserialize)]
struct WsQuery { token: Option<String> }
async fn websocket(State(state): State<AppState>, Query(query): Query<WsQuery>, ws: WebSocketUpgrade) -> Result<Response, AppError> {
    let expected = state.config.app_token.trim();
    if !expected.is_empty() && query.token.as_deref() != Some(expected) { return Err(AppError::Unauthorized); }
    Ok(ws.on_upgrade(move |socket| websocket_loop(state, socket)))
}

async fn websocket_loop(state: AppState, mut socket: WebSocket) {
    let initial = match build_bootstrap(&state).await {
        Ok(data) => json!({"event":"bootstrap","timestamp":Utc::now(),"data":data}),
        Err(err) => json!({"event":"error","timestamp":Utc::now(),"data":{"message":err.to_string()}}),
    };
    if socket.send(Message::Text(initial.to_string())).await.is_err() { return; }
    let mut receiver = state.events.subscribe();
    loop {
        tokio::select! {
            event = receiver.recv() => {
                match event {
                    Ok(event) => {
                        if let Ok(text) = serde_json::to_string(&event) {
                            if socket.send(Message::Text(text)).await.is_err() { break; }
                        }
                    }
                    Err(tokio::sync::broadcast::error::RecvError::Lagged(_)) => continue,
                    Err(_) => break,
                }
            }
            message = socket.next() => {
                match message {
                    Some(Ok(Message::Ping(value))) => { if socket.send(Message::Pong(value)).await.is_err() { break; } }
                    Some(Ok(Message::Text(text))) if text == "ping" => { if socket.send(Message::Text("pong".into())).await.is_err() { break; } }
                    Some(Ok(Message::Close(_))) | None | Some(Err(_)) => break,
                    _ => {}
                }
            }
        }
    }
}

async fn index(State(state): State<AppState>, headers: HeaderMap) -> Response {
    let base = if !state.config.base_path.is_empty() {
        state.config.base_path.clone()
    } else {
        forwarded_prefix(&headers).unwrap_or_default()
    };
    let body = INDEX_HTML.replace("__GREE_BASE_PATH__", &base);
    let mut response = Response::new(Body::from(body));
    response.headers_mut().insert(header::CONTENT_TYPE, HeaderValue::from_static("text/html; charset=utf-8"));
    response.headers_mut().insert(header::CACHE_CONTROL, HeaderValue::from_static("no-cache"));
    response
}

fn forwarded_prefix(headers: &HeaderMap) -> Option<String> {
    let raw = headers.get("x-forwarded-prefix")?.to_str().ok()?.split(',').next()?.trim();
    if raw.is_empty() || raw == "/" { return Some(String::new()); }
    if raw.contains('?') || raw.contains('#') || raw.split('/').any(|part| matches!(part, "." | "..")) { return None; }
    Some(format!("/{}", raw.trim_matches('/')))
}
async fn app_js() -> Response { static_response(APP_JS, "application/javascript; charset=utf-8", "no-cache") }
async fn theme_init_js() -> Response { static_response(THEME_INIT_JS, "application/javascript; charset=utf-8", "public, max-age=86400") }
async fn styles_css() -> Response { static_response(STYLES_CSS, "text/css; charset=utf-8", "no-cache") }
async fn manifest() -> Response { static_response(MANIFEST, "application/manifest+json", "public, max-age=3600") }
async fn service_worker() -> Response { static_response(SERVICE_WORKER, "application/javascript; charset=utf-8", "no-cache") }
async fn favicon() -> Response { static_response(FAVICON, "image/svg+xml", "public, max-age=86400") }
async fn language_index() -> Response {
    static_response(LANGUAGE_MANIFEST_JSON, "application/json; charset=utf-8", "no-cache")
}
async fn language_file(Path(file): Path<String>) -> Response {
    let code = file.strip_suffix(".json").unwrap_or(&file);
    if let Some((_, body)) = LANGUAGE_ASSETS.iter().find(|(language, _)| *language == code) {
        return static_response(*body, "application/json; charset=utf-8", "no-cache");
    }
    let mut response = Response::new(Body::from("Language not found"));
    *response.status_mut() = StatusCode::NOT_FOUND;
    response.headers_mut().insert(header::CONTENT_TYPE, HeaderValue::from_static("text/plain; charset=utf-8"));
    response
}
fn static_response(body: &'static str, content_type: &'static str, cache: &'static str) -> Response {
    let mut response = Response::new(Body::from(body));
    response.headers_mut().insert(header::CONTENT_TYPE, HeaderValue::from_static(content_type));
    response.headers_mut().insert(header::CACHE_CONTROL, HeaderValue::from_static(cache));
    response
}