TTMusic/lib/src/main/ets/parse/LyricParser.ts

import { IParser } from './IParser';
import { Lyric } from '../bean/Lyric';
import { LyricLine } from '../bean/LyricLine';
import { printD, printW } from '../extensions/Extension';
import { LyricWord } from '../bean/LyricWord';

/**
 * The parser to parse the string array of a standard lyric file.
 */
export class LyricParser implements IParser {
    // Example lyric file:
    // [ti:画心]
    // [ar:张靓颖]
    // [al:432326]
    // [by:]
    // [offset:0]
    // [00:00.10]画心 - 张靓颖
    // [01:05.49]看不穿 是你失落的魂魄

    /**
     * Parse the string array to a Lyric.
     * @param src The lyric source, a string array.
     * @returns A lyric instance.
     */
    parse(src: Array<string>): Lyric {
        let lyricLines = new Array<LyricLine>()
        let title = ""
        let artist = ""
        let album = ""
        let by = ""
        let offset = 0
        const ignoredTags = [ 'hash', 'sign', 'qq', 'total','Outro']; // 定义需要忽略的标签
        for (let i = 0; i < src.length; i++) {
            let line = src[i]
            console.info(`content The line of file:line ${line}`);
            if (line == "" || line == "\n" || line == "\r" || line == "\r\n" || line == "[Verse]" || line == "[Chorus]"
                || line == "[PreChorus]" || line == "[PreChorus]"||line == "[Bridge]") {
                printW("the lyric line is empty, carriage return or line feed, line index= " + i)
                continue
            }

            // 检查是否是需要忽略的标签
            const shouldIgnore = ignoredTags.some(tag  => line.indexOf(tag)  > 0);
            if (shouldIgnore) {
                printW(`the lyric line contains ignored tag, line index= ${i}`);
                continue;
            }
            if (line.indexOf("ti") > 0) {
                title = this.parseIdTag(line)
            } else if (line.indexOf("ar") > 0) {
                artist = this.parseIdTag(line)
            } else if (line.indexOf("al") > 0) {
                album = this.parseIdTag(line)
            } else if (line.indexOf("by") > 0) {
                by = this.parseIdTag(line)
            } else if (line.indexOf("offset") > 0) {
                offset = Number.parseInt(this.parseIdTag(line))
            } else {

                // 新增逐字歌词解析逻辑[mm:ss.xx] <mm:ss.xx>
                if (this.isWordByWordLyric(line)) {
                    const { timeline, words } = this.parseWordByWordLine(line, offset);
                    lyricLines.push(new LyricLine('', timeline, -1, words))
                    continue;
                }

                    // 新增：逐字歌词[]检测方括号逐字歌词格式 [mm:ss.xxx] 文字
                if (this.isSquareBracketWordByWordLyric(line))  {
                    const { timeline, words } = this.parseSquareBracketWordLine(line,  offset);
                    if (words.length  > 0) {
                        lyricLines.push(new  LyricLine('', timeline, -1, words))
                    }
                } else {
                    // 原逻辑处理，但支持逐字歌词
                    // [00:00.10]画心 - 张靓颖
                    // [01:05.49][02:08.40]看不穿 是你失落的魂魄
                    let spr = line.split(']');
                    if (spr.length <= 1) {
                        printW("the lyric line is no timestamp, line index= " + i)
                        continue
                    }
                    // parse text
                    let text = spr[spr.length-1]
                    // ... 原来的文本解析逻辑保持不变 ...
                    for (let i = 0; i < spr.length - 1; i++) {
                        let timeline = spr[i].replace("[", "");
                        let timeStamp = this.parseTimeline(timeline);
                        lyricLines.push(new LyricLine(text, timeStamp - offset, -1));
                    }
                }


            }
        }
        lyricLines.sort((l1, l2) => {
            return l1.beginTime - l2.beginTime
        })
        for (let i = 0;i < lyricLines.length; i++) {
            let lyricLine = lyricLines[i]
            if (i == lyricLines.length - 1) {
                lyricLine.nextTime = lyricLine.beginTime + 1000 - offset
            } else {
                let next = lyricLines[i+1]
                lyricLine.nextTime = next.beginTime
            }
        }
        // 为逐字歌词填充text（拼接所有歌词词）
        this.populateTextForWordLyrics(lyricLines);
        let result = new Lyric(artist, title, album, by, offset, lyricLines)
        return result
    }


    // 检测方括号格式的逐字歌词 [00:00.000]文[00:01.000]字
    private isSquareBracketWordByWordLyric(line: string): boolean {
        return /\[\d{2}:\d{2}\.\d{2,3}\]\S/.test(line);
    }

    // 解析方括号格式的逐字歌词行
    private parseSquareBracketWordLine(line: string, offset: number):
        { timeline: number, words: LyricWord[] } {

        const words: LyricWord[] = [];
        let firstTimeline = -1;

        // 正则匹配：[00:00.000]中文字
        const regex = /\[(\d{2}:\d{2}\.\d{2,3})\]([^\[]*)/g;
        let match;

        while ((match = regex.exec(line))  !== null) {
            const timeStr = match[1];   // 时间部分 00:00.000
            const word = match[2].trim(); // 歌词文本

            if (!word) continue; // 跳过空词

            const timeline = this.parseTimeline2(timeStr)  - offset;
            if (firstTimeline < 0) firstTimeline = timeline;

            words.push(new  LyricWord(word, timeline, 0));
        }

        // 计算每个词的持续时间
        for (let i = 0; i < words.length  - 1; i++) {
            words[i].duration = words[i + 1].startTime - words[i].startTime;
        }
        if (words.length  > 0 && words[words.length - 1].duration === 0) {
            words[words.length - 1].duration = 200; // 默认200ms
        }

        return { timeline: firstTimeline, words };
    }

    /******************** 时间解析增强 ********************/
    private parseTimeline2(timeString: string): number {
        // 增强支持毫秒/厘秒解析
        const parts = timeString.split(':');
        const minutes = parseInt(parts[0], 10);

        const secondParts = parts[1].split('.');
        const seconds = parseInt(secondParts[0], 10);
        const fraction = parseInt(secondParts[1], 10);

        // 根据小数位长度判断时间精度
        const milliseconds = secondParts[1].length === 2 ?
            fraction * 10 : // 厘秒转毫秒 (01 -> 10ms)
            fraction;       // 毫秒直接使用

        return minutes * 60000 + seconds * 1000 + milliseconds;
    }

    // 判断是否是逐字歌词行
    private isWordByWordLyric(line: string): boolean {
        const hasBracketTimestamp = /$$\d{2}:\d{2}\.\d{2,3}$$\S/.test(line);
        const hasAngleTimestamp = /<\d{2}:\d{2}\.\d{2,3}>/.test(line);
        return hasBracketTimestamp || hasAngleTimestamp;
    }

    // 解析逐字歌词行
    private parseWordByWordLine(line: string, offset: number): { timeline: number, words: LyricWord[] } {
        const words: LyricWord[] = [];
        let firstTimeline = -1;
        const regex = /((?:<|$$)(\d{2}:\d{2}\.\d{2,3})(?:>|$$))([^<\[]*)/g;
        let match;

        while ((match = regex.exec(line)) !== null) {
            const [_, tag, timeStr, word] = match;
            if (word.trim() === '') continue;

            const timeline = this.parseTimeline(timeStr) - offset;
            if (firstTimeline < 0) firstTimeline = timeline;

            words.push(new LyricWord(word.trim(), timeline, 0));
        }

        // 设置每个词持续时间（下一个词开始时间-当前词开始时间）
        for (let i = 0; i < words.length - 1; i++) {
            words[i].duration = words[i + 1].startTime - words[i].startTime;
        }
        if (words.length > 0 && words[words.length - 1].duration === 0) {
            // 最后一个词持续200ms
            words[words.length - 1].duration = 200;
        }

        return { timeline: firstTimeline, words };
    }

    // 为逐字歌词拼接整行文本
    private populateTextForWordLyrics(lyricLines: LyricLine[]) {
        lyricLines.forEach(line => {
            if (line.words.length > 0) {
                line.text = line.words.map(word => word.word).join('');
            }
        });
    }

    private parseIdTag(line: string): string {
        let spr = line.split(":")
        let spr1 = spr[1]
        let result = spr1.replace("]", "")
        return result
    }

    private parseTimeline(timeString: string): number {
        // 00:00.50
        let timeStringList = timeString.split(':')
        let minuteString = timeStringList[0] //00
        let minute = Number.parseInt(minuteString)
        let secondStrings = timeStringList[1] //00.50
        let secondStringList = secondStrings.split(".")
        let secondString = secondStringList[0] //00
        let millionSecondString = secondStringList[1] //50
        let seconds = Number.parseInt(secondString)
        let millionSecond = Number.parseInt(millionSecondString)
        return minute * 60000 + seconds * 1000 + millionSecond // covert to million seconds
    }
}