// Package utils 提供工具函数
package utils

import (
	"fmt"
	"regexp"
	"strconv"
	"strings"
	"time"

	"gitea.malaihome.work/ans/podcast_search/model"
)

// SrtParser 用于解析SRT格式的转录文件
type SrtParser struct {
	// SRT格式匹配正则表达式
	srtMatcher *regexp.Regexp
	// 换行符匹配正则表达式
	newlineMatcher *regexp.Regexp
}

// NewSrtParser 创建新的SRT解析器
func NewSrtParser() *SrtParser {
	return &SrtParser{
		srtMatcher: regexp.MustCompile(
			`(\d*)\s?((\d{2}):(\d{2}):(\d{2})[,|.](\d{3})) +--> +((\d{2}):(\d{2}):(\d{2})[,|.](\d{3})).*[\r\n]+\s*([^\r\n]+(\n|\r|\n)(?:.*))`,
		),
		newlineMatcher: regexp.MustCompile(`[\r\n]+`),
	}
}

// Parse 解析SRT格式的转录文件
func (p *SrtParser) Parse(srtData string) (*model.Transcript, error) {
	matches := p.srtMatcher.FindAllStringSubmatch(srtData, -1)
	subtitles := make([]model.Subtitle, 0)
	i := 0

	for _, match := range matches {
		i++

		// 索引可能存在也可能不存在
		index := i
		if match[1] != "" {
			parsedIndex, err := strconv.Atoi(match[1])
			if err == nil {
				index = parsedIndex
			}
		}

		// 解析开始时间
		startTimeHours, _ := strconv.Atoi(match[3])
		startTimeMinutes, _ := strconv.Atoi(match[4])
		startTimeSeconds, _ := strconv.Atoi(match[5])
		startTimeMilliseconds, _ := strconv.Atoi(match[6])

		// 解析结束时间
		endTimeHours, _ := strconv.Atoi(match[8])
		endTimeMinutes, _ := strconv.Atoi(match[9])
		endTimeSeconds, _ := strconv.Atoi(match[10])
		endTimeMilliseconds, _ := strconv.Atoi(match[11])

		// 计算开始和结束时间的Duration
		startDuration := time.Duration(startTimeHours)*time.Hour +
			time.Duration(startTimeMinutes)*time.Minute +
			time.Duration(startTimeSeconds)*time.Second +
			time.Duration(startTimeMilliseconds)*time.Millisecond

		endDuration := time.Duration(endTimeHours)*time.Hour +
			time.Duration(endTimeMinutes)*time.Minute +
			time.Duration(endTimeSeconds)*time.Second +
			time.Duration(endTimeMilliseconds)*time.Millisecond

		// 解析文本内容
		textLines := p.newlineMatcher.Split(match[12], -1)
		text := ""

		// 处理文本行
		for _, line := range textLines {
			if text == "" {
				text = line
			} else if strings.HasSuffix(text, " ") || strings.HasPrefix(line, " ") {
				text += line
			} else {
				text += " " + line
			}
		}

		// 创建字幕
		subtitle := model.Subtitle{
			Index:   index,
			Start:   startDuration,
			End:     endDuration,
			Data:    strings.TrimSpace(text),
			Speaker: "", // SRT格式通常不包含发言人信息
		}

		subtitles = append(subtitles, subtitle)
	}

	if len(subtitles) == 0 {
		return nil, fmt.Errorf("解析SRT失败: 未找到有效的字幕")
	}

	return &model.Transcript{
		Subtitles: subtitles,
	}, nil
}