from __future__ import annotations

from datetime import datetime, timezone
import os
import platform

from flask import Blueprint, jsonify, request, session

from app.core_settings import get_settings
from app.services.capabilities import build_capabilities
from app.services.catalog import get_catalog
from app.services.kiosk_settings import get_kiosk_settings_service
from app.services.auth import get_auth_service
from app.services.influx_http import InfluxHTTPService
from app.utils.serialization import to_plain


dashboard_blueprint = Blueprint("dashboard", __name__)
_APP_STARTED_AT = datetime.now(timezone.utc)


def _resolve_kiosk_mode(requested_mode: str, require_write_access: bool = False) -> tuple[str, str]:
    normalized_mode = (requested_mode or "private").strip().lower()
    auth_service = get_auth_service()

    if normalized_mode == "public":
        if require_write_access and auth_service.enabled and session.get("auth_role") != "admin":
            raise PermissionError("Brak uprawnien do edycji publicznego kiosku")
        return "public", "public"

    if normalized_mode != "private":
        raise ValueError("Mode musi byc jednym z: public, private")

    if not auth_service.enabled:
        return "private", "private"

    username = session.get("auth_user")
    if not username:
        raise PermissionError("Authentication required")
    return f"user:{username}", "private"


@dashboard_blueprint.get("/dashboard/config")
def dashboard_config():
    settings = get_settings()
    catalog = get_catalog()
    capabilities = build_capabilities(catalog)

    payload = {
        "app": {
            "name": settings.app_name,
            "version": settings.version,
            "site_name": settings.site_name,
            "timezone": settings.timezone,
            "installed_power_kwp": settings.installed_power_kwp,
        },
        "defaults": {
            "realtime_range": settings.realtime["history_default_range"],
            "analytics_range": settings.analytics["default_range"],
            "analytics_bucket": settings.analytics["default_bucket"],
            "tab": settings.frontend_defaults["tab"],
            "theme": settings.frontend_defaults["theme"],
            "language": settings.frontend_defaults["language"],
        },
        "auth": {
            "enabled": settings.auth["enabled"],
        },
        "i18n": settings.i18n,
        "capabilities": capabilities,
        "visible_entities": [
            {
                "metric_id": metric.id,
                "label": metric.label,
                "entity_id": metric.entity_id,
                "measurement": metric.measurement,
                "unit": metric.unit,
                "kind": metric.kind,
            }
            for metric in catalog.visible_entities()
        ],
    }
    return jsonify(to_plain(payload))


@dashboard_blueprint.get("/dashboard/kiosk-settings")
def dashboard_kiosk_settings():
    requested_mode = request.args.get("mode") or ("public" if request.args.get("publicKiosk") == "1" else "private")
    try:
        storage_mode, response_mode = _resolve_kiosk_mode(requested_mode)
        payload = get_kiosk_settings_service().get(storage_mode)
        payload["mode"] = response_mode
        return jsonify(to_plain(payload))
    except PermissionError as exc:
        return jsonify({"detail": str(exc)}), 403
    except ValueError as exc:
        return jsonify({"detail": str(exc)}), 400


@dashboard_blueprint.put("/dashboard/kiosk-settings")
def update_dashboard_kiosk_settings():
    payload = request.get_json(silent=True) or {}
    requested_mode = payload.get("mode", "private")
    try:
        storage_mode, response_mode = _resolve_kiosk_mode(requested_mode, require_write_access=True)
        updated = get_kiosk_settings_service().update_from_session(storage_mode, payload)
        updated["mode"] = response_mode
        return jsonify(to_plain(updated))
    except PermissionError as exc:
        return jsonify({"detail": str(exc)}), 403
    except ValueError as exc:
        return jsonify({"detail": str(exc)}), 400


@dashboard_blueprint.get("/dashboard/diagnostics")
def dashboard_diagnostics():
    auth_service = get_auth_service()
    try:
        auth_service.require_admin()
    except PermissionError as exc:
        return jsonify({"detail": str(exc)}), 403

    settings = get_settings()
    influx_diagnostics = InfluxHTTPService(settings).diagnose()
    now = datetime.now(timezone.utc)
    payload = {
        "app": {
            "name": settings.app_name,
            "version": settings.version,
            "debug": settings.debug,
            "timezone": settings.timezone,
            "site_name": settings.site_name,
            "installed_power_kwp": settings.installed_power_kwp,
            "auth_enabled": settings.auth["enabled"],
            "started_at": _APP_STARTED_AT.isoformat(),
            "uptime_seconds": max(int((now - _APP_STARTED_AT).total_seconds()), 0),
            "python_version": platform.python_version(),
            "pid": os.getpid(),
        },
        "api": {
            "status": "ok",
            "prefix": settings.api_prefix,
            "cors_origins_count": len(settings.cors_origins),
        },
        "influx": influx_diagnostics,
        "storage": {
            "sqlite_path": settings.storage["sqlite_path"],
            "historical_import_enabled": settings.history["enabled"],
            "auto_sync_enabled": settings.history["auto_sync_enabled"],
            "default_chunk_days": settings.history["default_chunk_days"],
        },
    }
    return jsonify(to_plain(payload))