feat: add genre filtering and longest streak display in TopSongs

src/main/scala/TopSongs/TopSongs.scala

@@ -31,7 +31,11 @@ enum MusicGenre:
   case Rock, Soul, Blues, Folk, Funk, Reggae, HipHop, NewWave, Electro, Metal
 
 // Define an Album with a union between a String and a MusicGenre
-class Album(title: String, label: String, genre: String|MusicGenre)
+class Album(title: String, label: String, genre: String|MusicGenre) {
+  def getGenre(): String | MusicGenre = {
+     genre
+  }
+}
 
 class Streak(val s: String) {
   val streak: Option[Int] = {
@@ -102,6 +106,11 @@ case class TopSongs(songs: List[Song] = List()) {
     })
   }
 
+  // This function filter the songs by a specific music gender
+  def filterByGenre(genre: MusicGenre): List[Song] = {
+    songs.filter(song => song.album.exists(_.getGenre() == genre))
+  }
+
   // This function counts the number of songs by each artist
   // It uses flatMap to extract the artist names from the songs
   // Then it groups the songs by artist name and counts the occurrences
@@ -165,7 +174,12 @@ case class TopSongs(songs: List[Song] = List()) {
     case (artist, count) => println(s"$artist: $count")
   }
 
-  println("----------");
+  println("----------")
+
+  // print the longest streak
+  val longestStreakSong = topSongs.longestStreak()
+  println(s"Longest streak: ${longestStreakSong.title} by ${longestStreakSong.singer.map(_.person.name).mkString(", ")} - ${longestStreakSong.rank._1.streak.getOrElse(0)} weeks")
+
   println("----------")
 
   // print the top N songs by weeks on chart