from typing import List
from .base import EffectProcessor

class SkipEffect(EffectProcessor):
    """跳过开头效果处理器"""
    
    def validate_params(self) -> bool:
        """验证参数：跳过的秒数"""
        if not self.params:
            return True  # 默认不跳过
            
        try:
            skip_seconds = float(self.params)
            return skip_seconds >= 0
        except ValueError:
            return False
            
    def generate_filter_args(self, video_input: str, effect_index: int) -> tuple[List[str], str]:
        """生成跳过开头效果的滤镜参数"""
        if not self.validate_params():
            return [], video_input
            
        if not self.params:
            return [], video_input
            
        skip_seconds = float(self.params)
        if skip_seconds <= 0:
            return [], video_input
            
        output_stream = f"[v_eff{effect_index}]"
        
        # 使用trim滤镜跳过开头
        filter_args = [f"{video_input}trim=start={skip_seconds}{output_stream}"]
        
        return filter_args, output_stream
        
    def get_effect_name(self) -> str:
        return "skip"