from __future__ import annotations

import asyncio
import logging
import subprocess
from pathlib import Path
from typing import Optional

import httpx
import yaml
from fastapi import FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from fastapi.staticfiles import StaticFiles

from .config_store import default_store
from .mediamtx_client import MediaMTXClient
from .models import (
  AppConfig,
  Camera,
  MediaMTXAddCameraRequest,
  MediaMTXCamera,
  MediaMTXConfigView,
  RecordingToggle,
  ScheduleUpdate,
  SchedulerEnabled,
)
from .recordings import list_recordings
from .scheduler import Scheduler

def _cors_origins() -> list[str]:
  return ["http://localhost:5173"]

logger = logging.getLogger("ipcam_dashboard")
PROJECT_ROOT = Path(__file__).resolve().parents[2]
DEFAULT_LOCAL_RECORDINGS_DIR = PROJECT_ROOT / "mediamtx" / "recordings"
MEDIAMTX_YML_PATH = PROJECT_ROOT / "mediamtx" / "mediamtx.yml"
MEDIAMTX_COMPOSE_PATH = PROJECT_ROOT / "mediamtx" / "docker-compose.yml"


app = FastAPI(title="IPCam Dashboard API")
app.add_middleware(
  CORSMiddleware,
  allow_origins=_cors_origins(),
  allow_credentials=True,
  allow_methods=["*"] ,
  allow_headers=["*"] ,
)

store = default_store()


def _extract_port(address: str, fallback: int) -> int:
  if not address:
    return fallback
  text = str(address).strip()
  if text.startswith(":"):
    text = text[1:]
  if ":" in text:
    text = text.rsplit(":", 1)[-1]
  try:
    value = int(text)
    return value if 1 <= value <= 65535 else fallback
  except ValueError:
    return fallback


def _load_mediamtx_yml() -> dict:
  if not MEDIAMTX_YML_PATH.exists():
    raise HTTPException(status_code=500, detail="mediamtx_yml_not_found")
  raw = MEDIAMTX_YML_PATH.read_text(encoding="utf-8")
  return yaml.safe_load(raw) or {}


def _save_mediamtx_yml(data: dict) -> None:
  MEDIAMTX_YML_PATH.write_text(
    yaml.safe_dump(data, sort_keys=False, allow_unicode=False),
    encoding="utf-8",
  )


def _build_mediamtx_view(data: dict) -> MediaMTXConfigView:
  api_port = _extract_port(str(data.get("apiAddress", ":9997")), 9997)
  webrtc_port = _extract_port(str(data.get("webrtcAddress", ":8889")), 8889)
  hosts = data.get("webrtcAdditionalHosts") or []
  host = hosts[0] if isinstance(hosts, list) and hosts else "127.0.0.1"

  path_defaults = data.get("pathDefaults") or {}
  record_enabled = bool(path_defaults.get("record", False))

  cameras: list[MediaMTXCamera] = []
  paths = data.get("paths") or {}
  if isinstance(paths, dict):
    for name, cfg in paths.items():
      if not isinstance(cfg, dict):
        continue
      source = cfg.get("source")
      if isinstance(source, str) and source.strip():
        cameras.append(MediaMTXCamera(name=str(name), rtsp_url=source))
  cameras.sort(key=lambda x: x.name)

  return MediaMTXConfigView(
    api_url=f"http://127.0.0.1:{api_port}",
    webrtc_url=f"http://{host}:{webrtc_port}",
    record_enabled=record_enabled,
    cameras=cameras,
  )


async def _sync_app_config_from_mediamtx() -> AppConfig:
  cfg = await store.load()
  data = _load_mediamtx_yml()
  view = _build_mediamtx_view(data)

  cfg.mediamtx_api_url = view.api_url
  cfg.mediamtx_webrtc_url = view.webrtc_url
  cfg.cameras = [Camera(name=c.name, rtsp_url=c.rtsp_url) for c in view.cameras]
  await store.save(cfg)
  return cfg


def _restart_mediamtx() -> dict:
  cmds = [
    ["docker", "compose", "-f", str(MEDIAMTX_COMPOSE_PATH), "restart", "mediamtx"],
    ["docker-compose", "-f", str(MEDIAMTX_COMPOSE_PATH), "restart", "mediamtx"],
  ]
  last_err = ""
  for cmd in cmds:
    try:
      proc = subprocess.run(
        cmd,
        cwd=str(MEDIAMTX_COMPOSE_PATH.parent),
        capture_output=True,
        text=True,
        timeout=40,
        check=False,
      )
      if proc.returncode == 0:
        return {"ok": True, "output": proc.stdout.strip()}
      last_err = (proc.stderr or proc.stdout or "").strip()
    except FileNotFoundError:
      last_err = "docker_command_not_found"
    except subprocess.TimeoutExpired:
      last_err = "docker_restart_timeout"
  raise HTTPException(status_code=500, detail=f"mediamtx_restart_failed: {last_err}")


async def _apply_recording(enabled: bool) -> None:
  cfg = await store.load()
  try:
    paths = await MediaMTXClient(
      api_url=cfg.mediamtx_api_url,
      username=cfg.mediamtx_api_user,
      password=cfg.mediamtx_api_pass,
    ).list_paths_status()
    names = [it.get("name") for it in (paths.get("items") or []) if isinstance(it, dict) and it.get("name")]
  except Exception:
    names = [c.name for c in cfg.cameras]
  if not names:
    return

  client = MediaMTXClient(
    api_url=cfg.mediamtx_api_url,
    username=cfg.mediamtx_api_user,
    password=cfg.mediamtx_api_pass,
  )
  await client.set_recording_bulk(names, enabled)


scheduler = Scheduler(apply=_apply_recording)


async def _scheduler_loop() -> None:
  while True:
    try:
      cfg = await store.load()
      await scheduler.tick(cfg.schedule)
    except Exception:
      logger.exception("scheduler_tick_failed")
    finally:
      await asyncio.sleep(60)

def _raise_mediamtx_http_error(err: httpx.HTTPError) -> None:
  if isinstance(err, httpx.HTTPStatusError):
    code = err.response.status_code
    if code == 401:
      raise HTTPException(status_code=502, detail="mediamtx_unauthorized")
    if code == 403:
      raise HTTPException(status_code=502, detail="mediamtx_forbidden")
    raise HTTPException(status_code=502, detail=f"mediamtx_http_{code}")
  raise HTTPException(status_code=502, detail="mediamtx_unreachable")


@app.on_event("startup")
async def _startup() -> None:
  cfg = await _sync_app_config_from_mediamtx()
  recordings_dir = Path(cfg.recordings_dir)

  # Backward-compatible migration: old defaults used "/recordings".
  if str(recordings_dir) == "/recordings":
    recordings_dir = DEFAULT_LOCAL_RECORDINGS_DIR
    cfg.recordings_dir = str(recordings_dir)
    await store.save(cfg)

  try:
    recordings_dir.mkdir(parents=True, exist_ok=True)
  except PermissionError:
    # Final fallback for local dev/deploy on same machine.
    recordings_dir = DEFAULT_LOCAL_RECORDINGS_DIR
    recordings_dir.mkdir(parents=True, exist_ok=True)
    cfg.recordings_dir = str(recordings_dir)
    await store.save(cfg)

  app.mount("/videos", StaticFiles(directory=str(recordings_dir)), name="videos")
  asyncio.create_task(_scheduler_loop())


@app.get("/api/health")
async def health() -> dict:
  return {"status": "ok"}


@app.get("/api/config")
async def get_config() -> AppConfig:
  return await _sync_app_config_from_mediamtx()


@app.get("/api/mediamtx/config")
async def get_mediamtx_config() -> MediaMTXConfigView:
  data = _load_mediamtx_yml()
  view = _build_mediamtx_view(data)
  await _sync_app_config_from_mediamtx()
  return view


@app.post("/api/mediamtx/cameras")
async def add_mediamtx_camera(payload: MediaMTXAddCameraRequest) -> MediaMTXConfigView:
  data = _load_mediamtx_yml()
  paths = data.setdefault("paths", {})
  if not isinstance(paths, dict):
    raise HTTPException(status_code=400, detail="invalid_mediamtx_paths")

  used = {str(k) for k in paths.keys()}
  idx = 1
  while f"cam{idx}" in used:
    idx += 1
  name = f"cam{idx}"
  paths[name] = {"source": payload.rtsp_url.strip()}
  _save_mediamtx_yml(data)
  await _sync_app_config_from_mediamtx()
  return _build_mediamtx_view(data)


@app.delete("/api/mediamtx/cameras/{name}")
async def delete_mediamtx_camera(name: str) -> MediaMTXConfigView:
  data = _load_mediamtx_yml()
  paths = data.get("paths") or {}
  if not isinstance(paths, dict) or name not in paths:
    raise HTTPException(status_code=404, detail="camera_not_found")
  del paths[name]
  data["paths"] = paths
  _save_mediamtx_yml(data)
  await _sync_app_config_from_mediamtx()
  return _build_mediamtx_view(data)


@app.post("/api/mediamtx/recording")
async def set_mediamtx_recording(data: RecordingToggle) -> MediaMTXConfigView:
  payload = _load_mediamtx_yml()
  path_defaults = payload.setdefault("pathDefaults", {})
  if not isinstance(path_defaults, dict):
    raise HTTPException(status_code=400, detail="invalid_mediamtx_path_defaults")
  path_defaults["record"] = bool(data.enabled)
  payload["pathDefaults"] = path_defaults
  _save_mediamtx_yml(payload)
  return _build_mediamtx_view(payload)


@app.post("/api/mediamtx/restart")
async def restart_mediamtx() -> dict:
  return _restart_mediamtx()


@app.get("/api/paths")
async def list_paths() -> dict:
  cfg = await store.load()
  client = MediaMTXClient(
    api_url=cfg.mediamtx_api_url,
    username=cfg.mediamtx_api_user,
    password=cfg.mediamtx_api_pass,
  )
  try:
    return await client.list_paths_status()
  except httpx.HTTPError as e:
    _raise_mediamtx_http_error(e)


@app.post("/api/recording")
async def toggle_recording(data: RecordingToggle) -> dict:
  try:
    await _apply_recording(data.enabled)
  except httpx.HTTPError as e:
    _raise_mediamtx_http_error(e)
  return {"enabled": data.enabled}


@app.post("/api/scheduler/enabled")
async def set_scheduler_enabled(data: SchedulerEnabled) -> AppConfig:
  cfg = await store.load()
  cfg.schedule.enabled = data.enabled
  await store.save(cfg)
  await scheduler.tick(cfg.schedule)
  return cfg


@app.post("/api/scheduler/schedule")
async def update_schedule(data: ScheduleUpdate) -> AppConfig:
  cfg = await store.load()
  cfg.schedule.weekdays_from = data.weekdays_from
  cfg.schedule.weekdays_to = data.weekdays_to
  cfg.schedule.weekend_all_day = data.weekend_all_day
  await store.save(cfg)
  await scheduler.tick(cfg.schedule)
  return cfg


@app.get("/api/recordings")
async def recordings(
  camera: str,
  date: Optional[str] = None,
  limit: int = 200,
  offset: int = 0,
) -> list[dict]:
  cfg = await _sync_app_config_from_mediamtx()
  if not any(c.name == camera for c in cfg.cameras):
    raise HTTPException(status_code=404, detail="camera_not_found")
  if limit < 1 or limit > 2000:
    raise HTTPException(status_code=400, detail="invalid_limit")
  if offset < 0:
    raise HTTPException(status_code=400, detail="invalid_offset")

  items = list_recordings(cfg.recordings_dir, camera, date, limit, offset)
  return [
    {
      "camera": it.camera,
      "filename": it.filename,
      "timestamp": it.timestamp,
      "url": it.url,
    }
    for it in items
  ]