"""
视频处理模块 - 基于MoviePy
Video Processing Module - Based on MoviePy

本模块提供视频编辑、剪辑、合成等功能
This module provides video editing, clipping, and composition features
"""

from typing import Optional, List, Tuple
import warnings

try:
    from moviepy.editor import (
        VideoFileClip, 
        AudioFileClip, 
        ImageClip,
        TextClip,
        CompositeVideoClip,
        concatenate_videoclips,
        vfx
    )
    MOVIEPY_AVAILABLE = True
except ImportError:
    MOVIEPY_AVAILABLE = False
    warnings.warn("moviepy库未安装，请运行: pip install moviepy")


class VideoEditor:
    """视频编辑器"""
    
    def __init__(self, video_path: Optional[str] = None):
        """
        初始化视频编辑器
        
        Args:
            video_path: 视频文件路径
        """
        if not MOVIEPY_AVAILABLE:
            raise ImportError("需要安装moviepy库")
        
        self.video = None
        if video_path:
            self.load_video(video_path)
    
    def load_video(self, video_path: str):
        """
        加载视频文件
        
        Args:
            video_path: 视频文件路径
        """
        self.video = VideoFileClip(video_path)
        return self
    
    def cut_video(self, start_time: float, end_time: float) -> 'VideoEditor':
        """
        剪辑视频
        
        Args:
            start_time: 开始时间（秒）
            end_time: 结束时间（秒）
            
        Returns:
            VideoEditor实例
        """
        if self.video is None:
            raise ValueError("请先加载视频")
        
        self.video = self.video.subclip(start_time, end_time)
        return self
    
    def resize_video(self, width: Optional[int] = None, height: Optional[int] = None) -> 'VideoEditor':
        """
        调整视频尺寸
        
        Args:
            width: 目标宽度
            height: 目标高度
            
        Returns:
            VideoEditor实例
        """
        if self.video is None:
            raise ValueError("请先加载视频")
        
        if width and height:
            self.video = self.video.resize((width, height))
        elif width:
            self.video = self.video.resize(width=width)
        elif height:
            self.video = self.video.resize(height=height)
        
        return self
    
    def add_audio(self, audio_path: str) -> 'VideoEditor':
        """
        添加音频
        
        Args:
            audio_path: 音频文件路径
            
        Returns:
            VideoEditor实例
        """
        if self.video is None:
            raise ValueError("请先加载视频")
        
        audio = AudioFileClip(audio_path)
        self.video = self.video.set_audio(audio)
        return self
    
    def add_text(self, text: str, position: Tuple[int, int] = ('center', 'center'), 
                 duration: Optional[float] = None, fontsize: int = 50, color: str = 'white') -> 'VideoEditor':
        """
        添加文字
        
        Args:
            text: 文字内容
            position: 文字位置
            duration: 显示时长（秒），None表示整个视频时长
            fontsize: 字体大小
            color: 字体颜色
            
        Returns:
            VideoEditor实例
        """
        if self.video is None:
            raise ValueError("请先加载视频")
        
        if duration is None:
            duration = self.video.duration
        
        txt_clip = TextClip(text, fontsize=fontsize, color=color)
        txt_clip = txt_clip.set_position(position).set_duration(duration)
        
        self.video = CompositeVideoClip([self.video, txt_clip])
        return self
    
    def speed_up(self, factor: float = 2.0) -> 'VideoEditor':
        """
        加速视频
        
        Args:
            factor: 加速倍数
            
        Returns:
            VideoEditor实例
        """
        if self.video is None:
            raise ValueError("请先加载视频")
        
        self.video = self.video.fx(vfx.speedx, factor)
        return self
    
    def fade_in(self, duration: float = 1.0) -> 'VideoEditor':
        """
        添加淡入效果
        
        Args:
            duration: 淡入时长（秒）
            
        Returns:
            VideoEditor实例
        """
        if self.video is None:
            raise ValueError("请先加载视频")
        
        self.video = self.video.fx(vfx.fadein, duration)
        return self
    
    def fade_out(self, duration: float = 1.0) -> 'VideoEditor':
        """
        添加淡出效果
        
        Args:
            duration: 淡出时长（秒）
            
        Returns:
            VideoEditor实例
        """
        if self.video is None:
            raise ValueError("请先加载视频")
        
        self.video = self.video.fx(vfx.fadeout, duration)
        return self
    
    def save(self, output_path: str, fps: int = 24, codec: str = 'libx264'):
        """
        保存视频
        
        Args:
            output_path: 输出文件路径
            fps: 帧率
            codec: 视频编码器
        """
        if self.video is None:
            raise ValueError("请先加载视频")
        
        self.video.write_videofile(output_path, fps=fps, codec=codec)
    
    def get_info(self) -> dict:
        """
        获取视频信息
        
        Returns:
            包含视频信息的字典
        """
        if self.video is None:
            raise ValueError("请先加载视频")
        
        return {
            'duration': self.video.duration,
            'fps': self.video.fps,
            'size': self.video.size,
            'width': self.video.w,
            'height': self.video.h
        }


class VideoMerger:
    """视频合并器"""
    
    @staticmethod
    def merge_videos(video_paths: List[str], output_path: str, method: str = 'concatenate'):
        """
        合并多个视频
        
        Args:
            video_paths: 视频文件路径列表
            output_path: 输出文件路径
            method: 合并方法，'concatenate'表示顺序连接
        """
        if not MOVIEPY_AVAILABLE:
            raise ImportError("需要安装moviepy库")
        
        clips = [VideoFileClip(path) for path in video_paths]
        
        if method == 'concatenate':
            final_clip = concatenate_videoclips(clips)
        else:
            raise ValueError(f"不支持的合并方法: {method}")
        
        final_clip.write_videofile(output_path)
        
        # 清理资源
        for clip in clips:
            clip.close()
        final_clip.close()


# 使用示例
if __name__ == "__main__":
    # 创建视频编辑器
    editor = VideoEditor("input_video.mp4")
    
    # 剪辑视频（0-10秒）
    editor.cut_video(0, 10)
    
    # 调整尺寸为720p
    editor.resize_video(width=1280, height=720)
    
    # 添加淡入淡出效果
    editor.fade_in(1.0).fade_out(1.0)
    
    # 保存视频
    editor.save("output_video.mp4")
    
    # 获取视频信息
    info = editor.get_info()
    print(f"视频时长: {info['duration']}秒")
    print(f"视频尺寸: {info['width']}x{info['height']}")