#!/usr/bin/env python3
"""Static regression checks for bounded-memory/background-worker contracts.

This is intentionally Rust-toolchain independent. It does not replace runtime RSS/
heap profiling; it prevents the source-level bounds audited for this release from
silently disappearing before compiler-enabled acceptance runs.
"""
from __future__ import annotations

from pathlib import Path

ROOT = Path(__file__).resolve().parents[1]


def read(path: str) -> str:
    return (ROOT / path).read_text(encoding="utf-8")


def require(path: str, *markers: str) -> None:
    text = read(path)
    for marker in markers:
        assert marker in text, f"{path}: missing memory contract: {marker}"


def forbid(path: str, *markers: str) -> None:
    text = read(path)
    for marker in markers:
        assert marker not in text, f"{path}: forbidden memory pattern returned: {marker}"


# Transform path: hard aggregate/decode/concurrency budgets and no JSON DOM tree.
require(
    "src/transform/mod.rs",
    "DEFAULT_MEMORY_BUDGET_BYTES: usize = 128 * 1024 * 1024",
    "pub memory_budget_bytes: usize",
    "pub max_inflight: usize",
    "try_reserve_transform_memory(required_memory, settings.memory_budget_bytes)",
    "try_reserve_transform_slot(settings.max_inflight)",
    "TRANSFORM_MEMORY_IN_USE_BYTES: AtomicUsize",
    "TRANSFORM_INFLIGHT: AtomicUsize",
    "pub struct ResourceUsage",
    "pub fn resource_usage(settings: &Settings)",
    "memory_reserved_bytes: TRANSFORM_MEMORY_IN_USE_BYTES.load",
    "Limited::new(body, settings.max_body_bytes)",
    ".try_reserve_exact(read)",
    '"memory_pressure"',
    '"concurrency_pressure"',
    "aggregation_is_bounded_even_when_content_length_is_false",
    "transform_memory_reservation_obeys_runtime_budget",
    "transform_inflight_reservation_obeys_runtime_limit",
)
require("src/transform/json.rs", "IgnoredAny::deserialize", "Vec::with_capacity(body.len())")
forbid("src/transform/json.rs", "use serde_json::Value", "from_slice::<Value>")
require("src/transform/css.rs", "let mut last_char: Option<char> = None")
require("src/transform/html.rs", "enum RawElement", "fn raw_tag(tag: &str)")

# Cache background work: all previously high-retention paths have hard bounds.
require(
    "src/cache/model.rs",
    "COLD_DELETE_FALLBACKS: usize = 2",
    "COLD_CLEANUP_SLOTS: usize = 1",
    "BACKGROUND_REVALIDATION_LIMIT: usize = 8",
    "pub cold_limit_bytes: u64",
    "pub cold_limit_entries: usize",
    "pub hot_auto_trim_enabled: bool",
    "pub hot_auto_trim_after_seconds: u64",
    "pub hot_auto_trim_target_percent: u8",
)
require(
    "src/admin/mod.rs",
    'payload["transform_resources"]',
    'payload["memory_accounting"]',
    '"non_cache_rss_includes_transform": true',
)
require(
    "src/cache/cold.rs",
    "BinaryHeap::with_capacity(requested_limit.saturating_add(1))",
    "self.cold_delete_fallbacks.clone().try_acquire_owned()",
    "self.cleanup_slots.clone().try_acquire_owned()",
    "std::mem::take(&mut delete)",
)
require(
    "src/cache/tickets.rs",
    "active.len() >= BACKGROUND_REVALIDATION_LIMIT",
)
require(
    "src/cache/collapse.rs",
    ".saturating_mul(64)",
    ".clamp(64, 256)",
    "settings.proactive_refresh_max_inflight as u64",
)
require(
    "src/cache/lifecycle.rs",
    "mpsc::channel(COLD_QUEUE)",
    "cold_delete_fallbacks: Arc::new(Semaphore::new(COLD_DELETE_FALLBACKS))",
    "cleanup_slots: Arc::new(Semaphore::new(COLD_CLEANUP_SLOTS))",
    "cache.trim_hot_idle();",
    "fn trim_hot_idle(&self)",
)

# Other long-lived/background facilities: queue/task/worker cardinality is bounded
# or owned by a cancellation-aware supervisor/TaskTracker.
require(
    "src/logging.rs",
    "HISTORY_CAPACITY: usize = 4096",
    "LIVE_STREAM_CAPACITY: usize = 4096",
    "mpsc::channel(SINK_QUEUE)",
    "self.sink.try_send(entry)",
    "pub capture_user_agent: bool",
    "pub capture_country: bool",
)
require(
    "src/traffic.rs",
    "QUEUE_CAPACITY: usize = 2048",
    "TOP_CAPACITY: usize = 32",
    "MAX_VHOSTS: usize = 64",
    "self.tx.try_send(sample)",
    "client_ips: TopTable",
)
require(
    "src/diagnostics.rs",
    "tokio::task::spawn_blocking(move || system_stats::sample(previous)).await",
    "stop.cancelled()",
    "pub fn trim_allocator() -> bool",
)
require(
    "src/runtime.rs",
    "Duration::from_secs(60)",
    "spawn_blocking(crate::diagnostics::trim_allocator)",
)
require(
    "src/upstream.rs",
    "Semaphore::new(16)",
    ".try_acquire_owned()",
    "tokio::time::timeout(DNS_TIMEOUT, lookup)",
)
require(
    "src/balance.rs",
    "if checks.len() >= 16 { break; }",
    "checks.abort_all()",
)
require(
    "src/stream.rs",
    "Semaphore::new(host.max_connections)",
    "mpsc::channel(64)",
    "JoinSet::new()",
)
require(
    "src/server.rs",
    "Semaphore::new(max_connections)",
    "let mut tasks = JoinSet::new()",
)
require(
    "src/runtime.rs",
    "tokio_util::task::TaskTracker::new()",
    "update_slots: Arc::new(Semaphore::new(8))",
    "inflight: Arc::new(Semaphore::new(max_inflight))",
)
require("src/acme.rs", "slot: Arc::new(Semaphore::new(1))", ".try_acquire_owned()")
require("src/docker.rs", "shutdown.cancelled()", "Duration::from_secs(5)")
require("src/update_check.rs", "shutdown.cancelled()", "tokio::time::sleep(interval)")

print("PASS: bounded-memory transform/cache contracts and background-worker limits are present.")