from typing import List, Dict, Any
from .base import EffectProcessor

class CameraShotEffect(EffectProcessor):
    """相机镜头效果处理器"""
    
    def validate_params(self) -> bool:
        """验证参数：start_time,duration,rotate_deg"""
        params = self.parse_params()
        if not params:
            return True  # 使用默认参数
            
        # 参数格式: "start_time,duration,rotate_deg"
        if len(params) > 3:
            return False
            
        try:
            for i, param in enumerate(params):
                if param == '':
                    continue
                if i == 2:  # rotate_deg
                    int(param)
                else:  # start_time, duration
                    float(param)
            return True
        except ValueError:
            return False
            
    def generate_filter_args(self, video_input: str, effect_index: int) -> tuple[List[str], str]:
        """生成相机镜头效果的滤镜参数"""
        if not self.validate_params():
            return [], video_input
            
        params = self.parse_params()
        
        # 设置默认值
        start = 3.0
        duration = 1.0
        rotate_deg = 0
        
        if len(params) >= 1 and params[0] != '':
            start = float(params[0])
        if len(params) >= 2 and params[1] != '':
            duration = float(params[1])
        if len(params) >= 3 and params[2] != '':
            rotate_deg = int(params[2])
            
        filter_args = []
        
        # 生成输出流标识符
        start_out_str = "[eff_s]"
        mid_out_str = "[eff_m]" 
        end_out_str = "[eff_e]"
        final_output = f"[v_eff{effect_index}]"
        
        # 分割视频流为三部分
        filter_args.append(f"{video_input}split=3{start_out_str}{mid_out_str}{end_out_str}")
        
        # 选择开始部分帧
        filter_args.append(f"{start_out_str}select=lt(n\\,{int(start * self.frame_rate)}){start_out_str}")
        
        # 选择结束部分帧
        filter_args.append(f"{end_out_str}select=gt(n\\,{int(start * self.frame_rate)}){end_out_str}")
        
        # 选择中间特定帧并扩展
        filter_args.append(f"{mid_out_str}select=eq(n\\,{int(start * self.frame_rate)}){mid_out_str}")
        filter_args.append(f"{mid_out_str}tpad=start_mode=clone:start_duration={duration:.4f}{mid_out_str}")
        
        # 如果需要旋转
        if rotate_deg != 0:
            filter_args.append(f"{mid_out_str}rotate=PI*{rotate_deg}/180{mid_out_str}")
            
        # 连接三部分
        filter_args.append(f"{start_out_str}{mid_out_str}{end_out_str}concat=n=3:v=1:a=0,setpts=N/{self.frame_rate}/TB{final_output}")
        
        return filter_args, final_output
        
    def get_effect_name(self) -> str:
        return "cameraShot"