# -*- coding: utf-8 -*-
"""Physical camera / microphone → YouTube RTMPS live relay (Windows DirectShow first)."""

from __future__ import annotations

import configparser
import os
import platform
import signal
import subprocess
import sys
import time
from pathlib import Path

from web2_proxy_config import merge_child_env

BASE_DIR = Path(__file__).resolve().parent
CONFIG_DIR = BASE_DIR / "config"
CAMERA_INI = CONFIG_DIR / "camera_live.ini"
YOUTUBE_INI = CONFIG_DIR / "youtube.ini"

RUNNING = True


def _on_signal(*_args):
    global RUNNING
    RUNNING = False


signal.signal(signal.SIGTERM, _on_signal)
signal.signal(signal.SIGINT, _on_signal)


def _load_camera() -> dict[str, str]:
    defaults = {
        "video_device": "",
        "audio_device": "",
        "width": "1280",
        "height": "720",
        "fps": "30",
        "bitrate": "2500",
        "use_gpu": "是",
    }
    if not CAMERA_INI.exists():
        return defaults
    cp = configparser.ConfigParser()
    cp.read(CAMERA_INI, encoding="utf-8")
    if not cp.has_section("camera"):
        return defaults
    out = dict(defaults)
    for k in out:
        if cp.has_option("camera", k):
            out[k] = (cp.get("camera", k) or "").strip()
    return out


def _load_youtube_key() -> tuple[str, str]:
    rtmps = "rtmps://a.rtmp.youtube.com/live2/"
    if not YOUTUBE_INI.exists():
        return "", rtmps
    cp = configparser.ConfigParser()
    cp.read(YOUTUBE_INI, encoding="utf-8")
    if not cp.has_section("youtube"):
        return "", rtmps
    key = ""
    for name, val in cp.items("youtube"):
        v = (val or "").strip()
        if name in ("key", "stream_key") and v and not v.startswith("#"):
            key = v
            break
    if key.startswith("rtmp://") or key.startswith("rtmps://"):
        return key, key
    return key, rtmps + key if key else ""


def _pick_nvenc(force_sw: bool) -> tuple[str, list[str]]:
    if force_sw:
        return "libx264", ["-preset", "ultrafast", "-tune", "zerolatency", "-profile:v", "high"]
    try:
        if platform.system().lower() not in ("windows", "linux"):
            raise RuntimeError("skip")
        check = subprocess.run(["nvidia-smi"], capture_output=True, timeout=5)
        if check.returncode != 0:
            raise RuntimeError("no nvidia")
        enc = subprocess.run(["ffmpeg", "-hide_banner", "-encoders"], capture_output=True, text=True, timeout=5)
        if "h264_nvenc" in (enc.stdout or ""):
            print("[INFO] 使用 NVENC 硬件编码")
            return "h264_nvenc", ["-profile:v", "high", "-tune", "ll", "-rc", "cbr"]
    except Exception:
        pass
    return "libx264", ["-preset", "ultrafast", "-tune", "zerolatency", "-profile:v", "high"]


def _build_cmd(cfg: dict[str, str], youtube_url: str) -> list[str]:
    w = int(cfg.get("width") or "1280")
    h = int(cfg.get("height") or "720")
    fps = int(float(cfg.get("fps") or "30"))
    br = int(cfg.get("bitrate") or "2500")
    b_v = f"{br}k"
    maxrate = f"{min(int(br * 1.2), 8000)}k"
    bufsize = f"{br * 2}k"
    video_dev = cfg.get("video_device") or ""
    audio_dev = cfg.get("audio_device") or ""
    force_sw = (cfg.get("use_gpu") or "").lower() in ("否", "0", "false", "无", "关", "off")
    codec, vopts = _pick_nvenc(force_sw)

    sys_name = platform.system().lower()
    if sys_name == "windows":
        inp = f"video={video_dev}"
        if audio_dev:
            inp += f":audio={audio_dev}"
        input_args = [
            "-f",
            "dshow",
            "-video_size",
            f"{w}x{h}",
            "-framerate",
            str(fps),
            "-i",
            inp,
        ]
    elif sys_name == "darwin":
        dev = video_dev or "0"
        input_args = ["-f", "avfoundation", "-framerate", str(fps), "-video_size", f"{w}x{h}", "-i", f"{dev}:0"]
    else:
        dev = video_dev or "/dev/video0"
        input_args = ["-f", "v4l2", "-framerate", str(fps), "-video_size", f"{w}x{h}", "-i", dev]
        if audio_dev:
            input_args = ["-f", "v4l2", "-i", dev, "-f", "alsa", "-i", audio_dev]

    return [
        "ffmpeg",
        "-hide_banner",
        "-loglevel",
        "info",
        *input_args,
        "-c:v",
        codec,
        *vopts,
        "-pix_fmt",
        "yuv420p",
        "-b:v",
        b_v,
        "-maxrate",
        maxrate,
        "-bufsize",
        bufsize,
        "-g",
        str(fps * 2),
        "-c:a",
        "aac",
        "-b:a",
        "128k",
        "-ar",
        "44100",
        "-f",
        "flv",
        youtube_url,
    ]


def main() -> None:
    print("[INFO] 摄像头 → YouTube 转播进程已启动")
    proc: subprocess.Popen | None = None
    while RUNNING:
        cfg = _load_camera()
        key, youtube_url = _load_youtube_key()
        if not key:
            print("[WARN] 请在 config/youtube.ini 配置 YouTube 串流密钥 (key=…)")
            time.sleep(5)
            continue
        if not (cfg.get("video_device") or "").strip():
            print("[WARN] 请在摄像头配置中选择 video_device")
            time.sleep(5)
            continue
        cmd = _build_cmd(cfg, youtube_url)
        print("[INFO] 启动 FFmpeg 摄像头推流…")
        print("[INFO] ffmpeg " + " ".join(cmd[1:]))
        env = merge_child_env(os.environ.copy())
        try:
            proc = subprocess.Popen(
                cmd,
                stdout=subprocess.PIPE,
                stderr=subprocess.STDOUT,
                text=True,
                encoding="utf-8",
                errors="replace",
                env=env,
                cwd=str(BASE_DIR),
            )
        except Exception as e:
            print(f"[ERROR] 无法启动 FFmpeg: {e}")
            time.sleep(5)
            continue

        assert proc.stdout is not None
        while RUNNING:
            line = proc.stdout.readline()
            if not line:
                break
            print(line.rstrip(), flush=True)
        code = proc.wait()
        proc = None
        if not RUNNING:
            break
        print(f"[WARN] FFmpeg 退出 code={code}，3 秒后重试…")
        time.sleep(3)

    if proc and proc.poll() is None:
        try:
            proc.terminate()
            proc.wait(timeout=5)
        except Exception:
            try:
                proc.kill()
            except Exception:
                pass
    print("[INFO] 摄像头转播进程已退出")


if __name__ == "__main__":
    main()