"""
main.py
=======

Container entry point for the Kavita light-novel metadata fetcher.

Reads configuration from environment variables, starts the orchestrator
and exposes the Flask WebApp on WEB_HOST:WEB_PORT.  Everything happens
through HTTP — there is no folder watcher and no file mover (Kavita is
the source of truth for the library content; this service only writes
metadata back to it).

Environment variables
---------------------
  Required:
    KAVITA_URL          base URL of the Kavita server, e.g. http://kavita:5000
    KAVITA_API_KEY      Kavita API key (Settings -> User -> API key)

  Optional:
    LIBRARY_IDS         comma-separated default library ids (e.g. "3,5").
                        Empty = user picks in the WebUI each time.
    LANGUAGE            default "en"
    REQUEST_TIMEOUT     default 30
    MATCH_PATH          default /config/matches.json
    WEB_PORT            default 8080
    WEB_HOST            default 0.0.0.0
"""

from __future__ import annotations

import os
import sys
from pathlib import Path

try:
    from dotenv import load_dotenv
    load_dotenv()
except ImportError:
    pass

# Make src/ importable when running as `python main.py`.
sys.path.insert(0, str(Path(__file__).resolve().parent / "src"))

from src.MatchesCache import MatchesCache                       # noqa: E402
from src.LightNovelOrchestrator import LightNovelOrchestrator   # noqa: E402
from src.MatchesWebApp import MatchesWebApp                     # noqa: E402


def _env_str(name: str, default: "str | None" = None,
             required: bool = False) -> "str | None":
    value = os.environ.get(name, default)
    if required and not value:
        print(f"[main] missing required env var: {name}", flush=True)
        sys.exit(2)
    return value


def _env_int(name: str, default: int) -> int:
    raw = os.environ.get(name)
    if raw is None or raw == "":
        return default
    try:
        return int(raw)
    except ValueError:
        print(f"[main] {name}={raw!r} is not a valid integer; "
              f"falling back to {default}", flush=True)
        return default


def _env_int_list(name: str) -> list[int]:
    raw = os.environ.get(name) or ""
    out: list[int] = []
    for part in raw.split(","):
        part = part.strip()
        if not part:
            continue
        try:
            out.append(int(part))
        except ValueError:
            print(f"[main] {name}: ignoring non-integer value {part!r}",
                  flush=True)
    return out


def main() -> int:
    kavita_url     = _env_str("KAVITA_URL",     required=True)
    kavita_api_key = _env_str("KAVITA_API_KEY", required=True)
    language       = _env_str("LANGUAGE", "en") or "en"
    request_timeout = _env_int("REQUEST_TIMEOUT", 30)
    match_path     = _env_str("MATCH_PATH", "/config/matches.json")
    web_host       = _env_str("WEB_HOST", "0.0.0.0") or "0.0.0.0"
    web_port       = _env_int("WEB_PORT", 8080)
    library_ids    = _env_int_list("LIBRARY_IDS")

    print(f"[main] kavita url    = {kavita_url}",     flush=True)
    print(f"[main] language      = {language}",       flush=True)
    print(f"[main] match path    = {match_path}",     flush=True)
    print(f"[main] libraries     = {library_ids or '(picked in WebUI)'}",
          flush=True)
    print(f"[main] web           = {web_host}:{web_port}", flush=True)

    cache = MatchesCache(match_path)
    orchestrator = LightNovelOrchestrator(
        kavita_url=kavita_url,
        kavita_api_key=kavita_api_key,
        matches_cache=cache,
        language=language,
        request_timeout=request_timeout,
    )

    app = MatchesWebApp(
        cache, orchestrator=orchestrator,
        default_library_ids=library_ids,
        host=web_host, port=web_port,
    )
    app.start()
    app.wait()
    return 0


if __name__ == "__main__":
    sys.exit(main())