#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
watcher.py —— 自研媒体刮削「监听服务」

功能：
  1. 用 watchdog 监听「清理后媒体目录」
  2. 检测到新媒体文件/目录写入稳定后，自动调用 media_scraper 刮削
  3. 刮削结果（媒体 + nfo + 海报）复制落库到成品目录
  4. 源目录保持原样，不写入任何文件

用法：
  ./watcher.py --config config.json          # 常驻服务
  ./watcher.py --config config.json --once   # 只扫描一次现有内容后退出（用于初始化存量）

config.json 字段：
  {
    "source": "<清理后媒体目录>",
    "dest":   "<成品落库目录>",
    "tmdb_api_key": "",      # TMDB API Key；留空时用 --mock 跑通管线
    "mock": true,            # true=模拟元数据(无Key验证用)；true后配好Key改为 false
    "settle": 6,             # 写入稳定等待秒数
    "language": "zh-CN"
  }
"""
import argparse
import json
import os
import sys
import threading
import time

from watchdog.events import FileSystemEventHandler
from watchdog.observers import Observer

# 复用核心刮削器
from media_scraper import (Config, Scraper, clean_ext, VIDEO_EXTS,
                           scan_and_scrape)


class Config2(Config):
    """扩展 Config：加载 watcher 的 source/dest/settle。"""

    def __init__(self, path):
        super().__init__(path)
        data = json.load(open(path, encoding="utf-8"))
        self.source = os.path.abspath(data.get("source", ""))
        self.dest = os.path.abspath(data.get("dest", ""))
        self.settle = int(data.get("settle", 6))
        self.mock = data.get("mock", False)
        if self.mock:
            self.tmdb_api_key = ""   # mock 模式不需要 key


class ScraperWorker:
    """把新媒体单元交给刮削器，带去重与写入稳定判定。"""

    def __init__(self, cfg, log):
        self.cfg = cfg
        self.log = log
        self.scraper = Scraper(cfg, cfg.dest, source_root=cfg.source, log=log)
        self.processed = set()          # 已处理的绝对路径
        self.lock = threading.Lock()
        os.makedirs(cfg.dest, exist_ok=True)

    def _is_stable(self, path):
        """判断文件/目录是否写入稳定：两次采样大小一致，最多等 settle 秒。"""
        def size(p):
            if os.path.isfile(p):
                return os.path.getsize(p)
            # 目录：取所有文件大小之和
            try:
                return sum(os.path.getsize(os.path.join(r, f))
                           for r, _, fs in os.walk(p) for f in fs)
            except OSError:
                return -1
        last = size(path)
        wait = self.cfg.settle
        while wait > 0:
            time.sleep(min(wait, 2))
            wait -= 2
            cur = size(path)
            if cur == last and cur >= 0:
                return True
            last = cur
        return True

    def handle(self, path):
        path = os.path.abspath(path)
        if not os.path.exists(path):
            return
        key = path if os.path.isdir(path) else os.path.dirname(path)
        with self.lock:
            if key in self.processed:
                return
            self.processed.add(key)
        try:
            self.log(f"检测到新媒体: {path}，等待写入稳定…")
            self._is_stable(path)
            self.log(f"开始刮削: {path}")
            scan_and_scrape(path, self.cfg.dest, self.scraper)
            self.log(f"完成: {path}")
        except Exception as e:
            self.log(f"处理失败 {path}: {e}")


class MediaHandler(FileSystemEventHandler):
    def __init__(self, worker):
        self.worker = worker
        self._threads = []
        self.lock = threading.Lock()

    def _dispatch(self, path):
        if os.path.basename(path).startswith("."):      # 隐藏/临时文件
            return
        ext = clean_ext(path)
        if ext in VIDEO_EXTS or os.path.isdir(path):
            t = threading.Thread(target=self.worker.handle, args=(path,),
                                 daemon=True)
            t.start()
            with self.lock:
                self._threads.append(t)
                self._threads = [x for x in self._threads if x.is_alive()]

    def on_created(self, event):
        self._dispatch(event.src_path)

    def on_moved(self, event):
        # 下载工具常见：先 .part 再改名成正式名，此时事件是 moved
        if not event.dest_path.endswith(".part"):
            self._dispatch(event.dest_path)

    def on_closed(self, event):
        pass


def main():
    ap = argparse.ArgumentParser(description="自研媒体刮削监听服务")
    ap.add_argument("--config", required=True, help="config.json 路径")
    ap.add_argument("--once", action="store_true",
                    help="扫描现有内容一次后退出（初始化存量）")
    args = ap.parse_args()

    cfg = Config2(args.config)
    if not cfg.source or not os.path.isdir(cfg.source):
        print(f"配置错误：source 不存在或未设置 -> {cfg.source}")
        sys.exit(1)

    def log(msg):
        line = f"[{time.strftime('%Y-%m-%d %H:%M:%S')}] {msg}"
        print(line)
        # 追加写日志文件
        logfile = os.path.join(cfg.dest, "..", "scraper.log")
        try:
            with open(logfile, "a", encoding="utf-8") as f:
                f.write(line + "\n")
        except OSError:
            pass

    worker = ScraperWorker(cfg, log)

    # 启动时先扫描一次现有内容（这样重启服务能补处理之前漏掉的媒体）
    for entry in os.listdir(cfg.source):
        p = os.path.join(cfg.source, entry)
        if os.path.isdir(p) or clean_ext(p) in VIDEO_EXTS:
            worker.handle(p)
    if args.once:
        log("存量扫描完成，退出")
        return

    # 常驻监听
    handler = MediaHandler(worker)
    observer = Observer()
    observer.schedule(handler, cfg.source, recursive=False)
    observer.start()
    log(f"开始监听: {cfg.source}  -> 成品目录: {cfg.dest}")
    try:
        while True:
            time.sleep(2)
    except KeyboardInterrupt:
        observer.stop()
    observer.join()


if __name__ == "__main__":
    main()