import os
import sys
import uuid
import subprocess
import tempfile
import threading
import time
from datetime import datetime, timedelta
import json
import glob
import requests
import logging
from shared_utils import task_registry, file_registry, file_lock, task_lock, add_task_log

# ======================
# 配置
# ======================
BASE_DIR = os.path.dirname(os.path.abspath(__file__))
FRAMES_ROOT = os.path.abspath("./frames")
TASK_TIMEOUT_HOURS = 1  # 任务过期时间（小时）

# 确保frames目录存在
os.makedirs(FRAMES_ROOT, exist_ok=True)

if sys.platform.startswith('win'):
    FFMPEG_PATH = os.path.join(BASE_DIR, 'lib', 'ffmpeg', 'bin', 'ffmpeg.exe')
    FFPROBE_PATH = os.path.join(BASE_DIR, 'lib', 'ffmpeg', 'bin', 'ffprobe.exe')
else:
    FFMPEG_PATH = os.path.join(BASE_DIR, 'lib', 'ffmpeg', 'bin', 'ffmpeg')
    FFPROBE_PATH = os.path.join(BASE_DIR, 'lib', 'ffmpeg', 'bin', 'ffprobe')

def log_subprocess_output(pipe, task_id, task_registry, task_lock, prefix=""):
    """从管道实时读取并记录日志"""
    if not pipe:
        return
    try:
        for line in iter(pipe.readline, ''):
            if line:
                clean_line = line.strip()
                if clean_line and task_id and task_registry and task_lock:
                    add_task_log(task_id, f"{prefix}{clean_line}", task_registry, task_lock)
    except Exception as e:
        if task_id and task_registry and task_lock:
            add_task_log(task_id, f"[日志读取错误] {e}", task_registry, task_lock)
    finally:
        pipe.close()
    
# ======================
# 任务处理函数
# ======================

def process_video_frame_extraction(data, file_registry, file_lock, task_id=None, task_registry=None, task_lock=None):
    """处理视频帧提取任务"""
    try:
        if task_id and task_registry and task_lock:
            add_task_log(task_id, "开始处理视频帧提取任务", task_registry, task_lock)

        logging.info(f"开始处理视频帧提取任务: {task_id}")

        # 提取参数
        video_url = data.get('video_url')
        video_bv = data.get('video_bv')  # 支持BV号
        w = data.get('w')
        h = data.get('h')
        fps = data.get('fps', 30)
        force_resolution = data.get('force_resolution', False)
        pad_to_target = data.get('pad_to_target', False)

        # 验证参数
        if not video_url and not video_bv:
            raise Exception("缺少必要参数: video_url 或 video_bv")
        if w is None or h is None:
            raise Exception("缺少必要参数: w, h")

        try:
            w = int(w)
            h = int(h)
            fps = float(fps)
            if w <= 0 or h <= 0 or fps <= 0:
                raise ValueError("参数必须为正数")
        except (ValueError, TypeError) as e:
            raise Exception(f"参数无效: {str(e)}")

        # 如果提供了BV号，自动生成Bilibili URL
        if not video_url and video_bv:
            video_bv = str(video_bv).strip()
            if not video_bv.startswith(('BV', 'bv')):
                raise Exception("video_bv 必须以 BV 或 bv 开头")
            video_url = f"https://www.bilibili.com/video/{video_bv.upper()}"

        # 准备目录
        job_dir = os.path.join(FRAMES_ROOT, task_id)
        os.makedirs(job_dir, exist_ok=True)

        if task_id and task_registry and task_lock:
            add_task_log(task_id, f"创建任务目录: {job_dir}", task_registry, task_lock)
            with task_lock:
                if task_id in task_registry:
                    task_registry[task_id]['progress'] = 10

        # 下载视频
        temp_base = os.path.join(tempfile.gettempdir(), task_id)

        # === 替换 yt-dlp 下载部分 ===
        if task_id and task_registry and task_lock:
            add_task_log(task_id, f"开始下载视频: {video_url}", task_registry, task_lock)

        yt_dlp_cmd = [
            sys.executable, '-m', 'yt_dlp',
            video_url,
            '-o', temp_base,
        ]

        # 使用 Popen 实时捕获 stderr
        proc = subprocess.Popen(
            yt_dlp_cmd,
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            text=True,
            bufsize=1,
            universal_newlines=True
        )

        # 启动日志线程（只读 stderr，因为 yt-dlp 进度在 stderr）
        stderr_thread = threading.Thread(
            target=log_subprocess_output,
            args=(proc.stderr, task_id, task_registry, task_lock, "[yt-dlp] "),
            daemon=True
        )
        stderr_thread.start()

        try:
            proc.wait(timeout=600)
            if proc.returncode != 0:
                raise subprocess.CalledProcessError(proc.returncode, yt_dlp_cmd)
        except subprocess.TimeoutExpired:
            proc.kill()
            raise Exception("yt-dlp 下载超时（超过10分钟）")
        finally:
            stderr_thread.join(timeout=5)  # 等待日志线程结束

        # 查找实际生成的文件
        candidates = glob.glob(temp_base + ".*")
        if not candidates:
            raise Exception("yt-dlp 执行成功但未生成任何视频文件")

        # 按修改时间取最新
        temp_video = max(candidates, key=os.path.getmtime)

        if task_id and task_registry and task_lock:
            add_task_log(task_id, "下载完成，开始获取视频信息", task_registry, task_lock)
            with task_lock:
                if task_id in task_registry:
                    task_registry[task_id]['progress'] = 40

        # 获取视频信息
        duration = get_video_duration(temp_video)

        # 构建滤镜
        vf = build_video_filter(w, h, fps, force_resolution, pad_to_target)

        # 提取帧
        if task_id and task_registry and task_lock:
            add_task_log(task_id, "开始提取视频帧", task_registry, task_lock)
            with task_lock:
                if task_id in task_registry:
                    task_registry[task_id]['progress'] = 50

        frame_pattern = os.path.join(job_dir, "frame_%06d.png")

        ffmpeg_cmd = [
            FFMPEG_PATH, '-y',
            '-i', temp_video,
            '-vf', vf,
            '-pix_fmt', 'rgb24',
            '-stats',          # 关键：启用进度统计
            '-v', 'info',      # 确保输出级别足够
            frame_pattern
        ]

        proc = subprocess.Popen(
            ffmpeg_cmd,
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            text=True,
            bufsize=1,
            universal_newlines=True
        )

        # FFmpeg 的进度在 stderr
        stderr_thread = threading.Thread(
            target=log_subprocess_output,
            args=(proc.stderr, task_id, task_registry, task_lock, "[FFmpeg] "),
            daemon=True
        )
        stderr_thread.start()

        try:
            proc.wait()
            if proc.returncode != 0:
                raise subprocess.CalledProcessError(proc.returncode, ffmpeg_cmd)
        finally:
            stderr_thread.join(timeout=5)

        # 获取输出分辨率
        if task_id and task_registry and task_lock:
            add_task_log(task_id, "分析输出结果", task_registry, task_lock)
            with task_lock:
                if task_id in task_registry:
                    task_registry[task_id]['progress'] = 80

        out_w, out_h = get_output_resolution(job_dir)
        total_frames = len([f for f in os.listdir(job_dir) if f.endswith('.png')])

        # 检查音频
        audio_exists = has_audio(temp_video)

        if audio_exists:
            if task_id and task_registry and task_lock:
                add_task_log(task_id, "提取音频（左/右/混合声道）", task_registry, task_lock)
                with task_lock:
                    if task_id in task_registry:
                        task_registry[task_id]['progress'] = 90

            # 公共参数
            dfpwm_args = [
                FFMPEG_PATH, '-y',
                '-i', temp_video,
                '-vn',
                '-ar', '48000',
                '-ac', '1',
                '-f', 'dfpwm'
            ]

            # 混合声道
            dfpwm_path_mix = os.path.join(job_dir, "audio.dfpwm")
            subprocess.run(
                dfpwm_args + [dfpwm_path_mix],
                check=True, capture_output=True
            )

            # 左声道
            dfpwm_path_left = os.path.join(job_dir, "audio_left.dfpwm")
            subprocess.run(
                dfpwm_args + ['-af', 'pan=mono|c0=c0'] + [dfpwm_path_left],
                check=True, capture_output=True
            )

            # 右声道
            dfpwm_path_right = os.path.join(job_dir, "audio_right.dfpwm")
            subprocess.run(
                dfpwm_args + ['-af', 'pan=mono|c0=c1'] + [dfpwm_path_right],
                check=True, capture_output=True
            )

        # 生成结果
        result_data = {
            "duration_seconds": round(duration, 3),
            "total_frames": total_frames,
            "fps": fps,
            "output_resolution": {"w": out_w, "h": out_h},
            "frame_urls": [f"/frames/{task_id}/frame_{i:06d}.png" for i in range(1, total_frames + 1)],
            "audio_dfpwm_url": f"/frames/{task_id}/audio.dfpwm" if has_audio else None,
            "audio_dfpwm_left_url": f"/frames/{task_id}/audio_left.dfpwm" if has_audio else None,
            "audio_dfpwm_right_url": f"/frames/{task_id}/audio_right.dfpwm" if has_audio else None
        }

        # 注册文件到文件注册表
        with file_lock:
            for frame_file in glob.glob(os.path.join(job_dir, "frame_*.png")):
                filename = os.path.basename(frame_file)
                file_id = f"frame_{task_id}_{filename}"
                file_registry[file_id] = {
                    'path': os.path.abspath(frame_file),
                    'filename': filename,
                    'last_access': time.time(),
                    'download_count': 0
                }

            if audio_exists:
                for audio_file in ["audio.dfpwm", "audio_left.dfpwm", "audio_right.dfpwm"]:
                    audio_path = os.path.join(job_dir, audio_file)
                    if os.path.exists(audio_path):
                        file_id = f"audio_{task_id}_{audio_file}"
                        file_registry[file_id] = {
                            'path': os.path.abspath(audio_path),
                            'filename': audio_file,
                            'last_access': time.time(),
                            'download_count': 0
                        }

        if task_id and task_registry and task_lock:
            add_task_log(task_id, "视频帧提取任务完成", task_registry, task_lock)
            with task_lock:
                if task_id in task_registry:
                    task_registry[task_id]['progress'] = 100

        return {
            'status': 'success',
            'result': result_data,
            'task_id': task_id,
            'temp_dir': job_dir
        }

    except subprocess.CalledProcessError as e:
        stderr_str = e.stderr.strip() if e.stderr else ""
        stdout_str = e.stdout.strip() if e.stdout else ""
        error_output = stderr_str or stdout_str or str(e)
        error_msg = error_output[-500:] if len(error_output) > 500 else error_output

        if task_id and task_registry and task_lock:
            add_task_log(task_id, f"FFmpeg处理失败: {error_msg}", task_registry, task_lock)

        return {'error': f'FFmpeg处理失败: {error_msg}'}
    except requests.RequestException as e:
        error_msg = f'视频下载失败: {str(e)}'
        if task_id and task_registry and task_lock:
            add_task_log(task_id, error_msg, task_registry, task_lock)
        return {'error': error_msg}
    except Exception as e:
        error_msg = f'处理失败: {str(e)}'
        if task_id and task_registry and task_lock:
            add_task_log(task_id, error_msg, task_registry, task_lock)
        return {'error': error_msg}
    finally:
        # 清理临时视频文件
        for f in glob.glob(os.path.join(tempfile.gettempdir(), f"{task_id}.*")):
            try:
                os.remove(f)
            except:
                pass

# ======================
# 辅助函数
# ======================

def get_video_duration(video_path):
    """获取视频时长"""
    result = subprocess.run([
        FFPROBE_PATH, '-v', 'error',
        '-show_entries', 'format=duration',
        '-of', 'csv=p=0',
        video_path
    ], capture_output=True, text=True, check=True)

    duration_str = result.stdout.strip()
    return float(duration_str) if duration_str and duration_str != 'N/A' else 0.0

def build_video_filter(w, h, fps, force_resolution, pad_to_target):
    """构建视频滤镜"""
    if force_resolution:
        return f"scale={w}:{h},fps={fps}"
    else:
        scale_expr = f"scale='min({w},iw*min(1,{h}/ih))':'min({h},ih*min(1,{w}/iw))'"
        if pad_to_target:
            return f"{scale_expr},pad={w}:{h}:(ow-iw)/2:(oh-ih)/2,fps={fps}"
        else:
            return f"{scale_expr},fps={fps}"

def get_output_resolution(job_dir):
    """获取输出分辨率"""
    first_frame = None
    for f in sorted(os.listdir(job_dir)):
        if f.endswith('.png'):
            first_frame = os.path.join(job_dir, f)
            break

    if first_frame:
        probe_res = subprocess.run([
            FFPROBE_PATH, '-v', 'error',
            '-select_streams', 'v:0',
            '-show_entries', 'stream=width,height',
            '-of', 'csv=p=0',
            first_frame
        ], capture_output=True, text=True, check=True)

        out_w, out_h = map(int, probe_res.stdout.strip().split(','))
        return out_w, out_h

    return 0, 0

def has_audio(video_path):
    """检查视频是否有音频"""
    probe_streams = subprocess.run([
        FFPROBE_PATH, '-v', 'error',
        '-show_entries', 'stream=codec_type',
        '-of', 'csv=p=0',
        video_path
    ], capture_output=True, text=True)

    return 'audio' in probe_streams.stdout.lower()