remove harcoded html tag, parses next chunks to find track

src/main/java/me/bobert/netneutrality/music/source/UdioAudioSourceManager.java

@@ -5,10 +5,8 @@ package me.bobert.netneutrality.music.source;
  * https://discord.gg/qUa6zNFZsd
  */
 
-import com.fasterxml.jackson.core.JsonParseException;
 import com.sedmelluq.discord.lavaplayer.player.AudioPlayerManager;
 import com.sedmelluq.discord.lavaplayer.source.AudioSourceManager;
-import com.sedmelluq.discord.lavaplayer.tools.DataFormatTools;
 import com.sedmelluq.discord.lavaplayer.tools.ExceptionTools;
 import com.sedmelluq.discord.lavaplayer.tools.FriendlyException;
 import com.sedmelluq.discord.lavaplayer.tools.JsonBrowser;
@@ -30,6 +28,7 @@ import java.io.DataInput;
 import java.io.DataOutput;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
+import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 import static com.sedmelluq.discord.lavaplayer.tools.FriendlyException.Severity.SUSPICIOUS;
@@ -38,6 +37,10 @@ public class UdioAudioSourceManager implements AudioSourceManager {
     private static final Logger log = LogManager.getLogger(UdioAudioSourceManager.class);
     private static final String TRACK_URL_REGEX = "^https://www.udio.com/songs/[0-9A-Za-z]+$";
     private static final Pattern trackUrlPattern = Pattern.compile(TRACK_URL_REGEX);
+    private static final Pattern NEXT_PUSH_PATTERN = Pattern.compile(
+        "self\\.__next_f\\.push\\(\\[(\\d+),\"(.*?)\"]\\)",
+        Pattern.DOTALL
+    );
     private final HttpInterfaceManager httpInterfaceManager;
 
     public UdioAudioSourceManager() {
@@ -120,24 +123,109 @@ public class UdioAudioSourceManager implements AudioSourceManager {
     }
 
     protected JsonBrowser loadTrackInfoFromPageContent(String content) throws IOException {
-        String startTag = "self.__next_f.push([1,\"33:";
-        String endTag = "\\n\"])";
+        Matcher matcher = NEXT_PUSH_PATTERN.matcher(content);
+        while (matcher.find()) {
+            String payload = matcher.group(2);
+            JsonBrowser trackInfo = tryExtractTrackFromNextChunk(payload);
 
-        String json = DataFormatTools.extractBetween(content, startTag, endTag);
-        if (json == null || json.isEmpty() || json.equals("null")) {
-            log.error("Track JSON not found in page");
-            return null;
+            if (trackInfo != null) {
+                return trackInfo;
+            }
         }
 
+        return null;
+    }
+
+    private JsonBrowser tryExtractTrackFromNextChunk(String payload) {
         try {
-            String unescapedJson = json.replace("\\", "");
-            JsonBrowser parsedJson = JsonBrowser.parse(unescapedJson);
+            int trackKeyIndex = payload.indexOf("\\\"track\\\":{");
+            if (trackKeyIndex < 0) {
+                return null;
+            }
 
-            return parsedJson.index(3).get("children").index(3).get("children").index(3).get("track");
-        } catch (JsonParseException e) {
-            log.error("Failed to parse track JSON: {}", json);
-            return null;
+            int objectStart = payload.indexOf('{', trackKeyIndex);
+            if (objectStart < 0) {
+                return null;
+            }
+
+            String escapedTrackJson = extractJsonObjectFromString(payload, objectStart);
+            if (escapedTrackJson == null) {
+                return null;
+            }
+
+            String trackJson = unescapeJsonStringFragment(escapedTrackJson);
+            JsonBrowser track = JsonBrowser.parse(trackJson);
+
+            if (isValidTrack(track)) {
+                return track;
+            }
+        } catch (Exception e) {
+            log.debug("Skipping unparsable track payload fragment", e);
         }
+
+        return null;
+    }
+
+    /**
+     * Extracts a JSON object from a given string starting at the specified index. This method parses the string
+     * to locate and retrieve the JSON object, ensuring proper handling of nested structures and escaped characters.
+     *
+     * @param text The input string containing the JSON object to be extracted.
+     * @param startIndex The index at which to start searching for the JSON object within the input string.
+     * @return The extracted JSON object as a string, or {@code null} if no valid JSON object is found.
+     */
+    private String extractJsonObjectFromString(String text, int startIndex) {
+        boolean escaped = false;
+        boolean inString = false;
+        int depth = 0;
+
+        for (int i = startIndex; i < text.length(); i++) {
+            char c = text.charAt(i);
+
+            if (escaped) {
+                escaped = false;
+                continue;
+            }
+
+            if (c == '\\') {
+                escaped = true;
+                continue;
+            }
+
+            if (c == '"') {
+                inString = !inString;
+                continue;
+            }
+
+            if (inString) {
+                continue;
+            }
+
+            if (c == '{') {
+                depth++;
+            } else if (c == '}') {
+                depth--;
+                if (depth == 0) {
+                    return text.substring(startIndex, i + 1);
+                }
+            }
+        }
+
+        return null;
+    }
+
+    private String unescapeJsonStringFragment(String value) {
+        return value.replace("\\\"", "\"").replace("\\\\", "\\");
+    }
+
+    private boolean isValidTrack(JsonBrowser track) {
+        return track != null
+            && !track.isNull()
+            && !track.get("title").isNull()
+            && !track.get("artist").isNull()
+            && !track.get("duration").isNull()
+            && !track.get("song_path").isNull()
+            && !track.get("image_path").isNull();
     }
 
     private String getArtworkUrlFromImagePath(JsonBrowser trackInfo) {