feat(synced-lyrics): multiple lyric sources (#2383)

Co-authored-by: JellyBrick <shlee1503@naver.com>

src/plugins/synced-lyrics/parsers/lrc.ts

@@ -0,0 +1,89 @@
+interface LRCTag {
+  tag: string;
+  value: string;
+}
+
+interface LRCLine {
+  time: string;
+  timeInMs: number;
+  duration: number;
+  text: string;
+}
+
+interface LRC {
+  tags: LRCTag[];
+  lines: LRCLine[];
+}
+
+const tagRegex = /^\[(?<tag>\w+):\s*(?<value>.+?)\s*\]$/;
+// prettier-ignore
+const lyricRegex = /^\[(?<minutes>\d+):(?<seconds>\d+)\.(?<milliseconds>\d+)\](?<text>.+)$/;
+
+export const LRC = {
+  parse: (text: string): LRC => {
+    const lrc: LRC = {
+      tags: [],
+      lines: [],
+    };
+
+    let offset = 0;
+    let previousLine: LRCLine | null = null;
+
+    for (const line of text.split('\n')) {
+      if (!line.trim().startsWith('[')) continue;
+
+      const lyric = line.match(lyricRegex)?.groups;
+      if (!lyric) {
+        const tag = line.match(tagRegex)?.groups;
+        if (tag) {
+          if (tag.tag === 'offset') {
+            offset = parseInt(tag.value);
+            continue;
+          }
+
+          lrc.tags.push({
+            tag: tag.tag,
+            value: tag.value,
+          });
+        }
+        continue;
+      }
+
+      const { minutes, seconds, milliseconds, text } = lyric;
+      const timeInMs =
+        parseInt(minutes) * 60 * 1000 +
+        parseInt(seconds) * 1000 +
+        parseInt(milliseconds);
+
+      const currentLine: LRCLine = {
+        time: `${minutes}:${seconds}:${milliseconds}`,
+        timeInMs,
+        text: text.trim(),
+        duration: Infinity,
+      };
+
+      if (previousLine) {
+        previousLine.duration = timeInMs - previousLine.timeInMs;
+      }
+
+      previousLine = currentLine;
+      lrc.lines.push(currentLine);
+    }
+
+    for (const line of lrc.lines) {
+      line.timeInMs += offset;
+    }
+
+    const first = lrc.lines.at(0);
+    if (first && first.timeInMs > 300) {
+      lrc.lines.unshift({
+        time: '0:0:0',
+        timeInMs: 0,
+        duration: first.timeInMs,
+        text: '',
+      });
+    }
+
+    return lrc;
+  },
+};