Add synchronized lyrics support (only LRC format at the moment)

app/src/main/java/com/kabouzeid/gramophone/model/lyrics/SynchronizedLyrics.java

@@ -0,0 +1,32 @@
+package com.kabouzeid.gramophone.model.lyrics;
+
+import android.util.SparseArray;
+
+public abstract class SynchronizedLyrics {
+    public final SparseArray<String> lines = new SparseArray<>();
+
+    public static SynchronizedLyrics parse(String data)
+    {
+        return new SynchronizedLyricsLRC(data); // no another formats at the moment
+    }
+
+    public String getLine(int time)
+    {
+        time += 500; // small time adjustment to display line before it actually starts
+
+        int lastLineTime = lines.keyAt(0);
+
+        for(int i = 0; i < lines.size(); i++) {
+            int lineTime = lines.keyAt(i);
+
+            if(time >= lineTime) {
+                lastLineTime = lineTime;
+            }
+            else {
+                break;
+            }
+        }
+
+        return lines.get(lastLineTime);
+    }
+}

app/src/main/java/com/kabouzeid/gramophone/model/lyrics/SynchronizedLyricsLRC.java

@@ -0,0 +1,47 @@
+package com.kabouzeid.gramophone.model.lyrics;
+
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public class SynchronizedLyricsLRC extends SynchronizedLyrics {
+    private static Pattern LRC_LINE_PATTERN = Pattern.compile("((?:\\[.*?\\])+)(.*)");
+    private static Pattern LRC_TIME_PATTERN = Pattern.compile("\\[(\\d\\d):(\\d\\d)(?:\\.(\\d\\d))\\]");
+
+    public SynchronizedLyricsLRC(String data)
+    {
+        if(data == null || data.isEmpty()) {
+            return;
+        }
+
+        String[] lines = data.split("\r?\n");
+
+        for(String line : lines) {
+            line = line.trim();
+            if(line.isEmpty()) {
+                continue;
+            }
+
+            Matcher matcher = SynchronizedLyricsLRC.LRC_LINE_PATTERN.matcher(line);
+            if(matcher.find()) {
+                String time = matcher.group(1);
+                String text = matcher.group(2);
+
+                Matcher timeMatcher = SynchronizedLyricsLRC.LRC_TIME_PATTERN.matcher(time);
+                while(timeMatcher.find()) {
+                    int m = 0, s = 0, x = 0;
+                    try {
+                        m = Integer.parseInt(timeMatcher.group(1));
+                        s = Integer.parseInt(timeMatcher.group(2));
+                        x = Integer.parseInt(timeMatcher.group(3));
+                    } catch (NumberFormatException ex) {
+                        ex.printStackTrace();
+                    }
+                    int ms = x*10 + s*1000 + m*60000;
+
+                    this.lines.append(ms, text);
+                }
+            }
+        }
+    }
+
+}