Untitled

import java.util.*;

// Nimai Belur
// 09/30/2024
// CSE 122
// C0: Warm Up
// TA: Cora Supasatit

// This class is a Music Box. It gives the user the power to compose their own song by entering 
// different notes and can find some of the most commonly used notes in the song

public class MusicBox {
    public static final String NOTES = "CDEFGAB";
    public static final String SHARP = "♯";
    public static final String FLAT = "♭";
    
    public static void main(String[] args) {
        Scanner console = new Scanner(System.in);
        String[][] song = composeSong(console);
        System.out.println("Returned song 2D array:");
        for (int i = 0; i < song.length; i++) {
            for (int j = 0; j < song[0].length; j++) {
                System.out.print(song[i][j] + " "); 
            }
            System.out.println();
        }
    }

    // Behavior - Asks users to create a song by entering the number of melodies and their length, 
    // and creates an accordingly sized array
    
    // Exceptions - N/a

    // Returns - String[][] - Returns a 2D array comprised of the notes entered by the user

    //Paramters - Scanner - Asks user for input about number of melodies and their length
    public static String[][] composeSong(Scanner input){
        //gets number of melodies from user
        System.out.print("Enter the number of melodies: ");
        String melodies = input.nextLine();
        int numMelodies = Integer.parseInt(melodies);

        //gets length of each melody from user
        System.out.print("Enter the length of each melody: ");
        melodies = input.nextLine();
        int lenMelodies = Integer.parseInt(melodies);
        System.out.println();

        //Creating empty 2D array of notes to be filled with fillBoard
        String[][] songArray = new String[numMelodies][lenMelodies];

        //calls fillBoard to add in the notes for each song
        return fillBoard(input, songArray);
    }

    // Behavior - Asks users to enter notes and places them into a 2D array

    // Exceptions - N/a

    // Returns - String[][] - Returns a 2D array comprised of the notes entered by the user

    // Paramters - Scanner - Asks user for input about what notes should be entered into the array

    // String[][] - Takes in an empty array that has the correct amount of rows for number melodies 
    // and columns for length of the melodies
    public static String[][] fillBoard(Scanner object, String[][] songArray){
        for(int i=0; i<songArray.length; i++){
            //Shows users which melody is being composed
            System.out.println("Composing melody #" + (i+1));
            for(int j=0; j<songArray[0].length; j++){
                //Shows which note the user is entering
                System.out.print("  Enter note #" + (j+1) +": ");
                String note = object.nextLine();
                //Add note to array
                songArray[i][j]=note;
            }
            System.out.println();
        }
        return songArray;
    }

    // Behavior - Finds the most common naturals within the song

    // Exceptions - N/a

    // Returns - String[] - Returns an array of the most common naturals within each line of the song

    // Paramters - String[][] - Takes in a 2D array of notes that make up a song
    public static String[] mostCommonNaturals(String[][] song){
        //Array has size song.length to represent every line of the song
        String[] commonNotes = new String[song.length];
        for(int k=0; k<song.length; k++){
            int[] noteCounts = countNotes(song[k]);
            commonNotes[k] = mostCommonNote(noteCounts);
        }

        return commonNotes;
    }

    // Behavior - Counts the number of times each note occurs in the given line of the song

    // Exceptions - N/a

    // Returns - int[] - Returns an array with the number of times that each note occurs in the line

    // Paramters - String[] - Array of notes that make up the line of the song
    public static int[] countNotes(String[] songLine){
        int[] noteCounts = new int[NOTES.length()];
        for(int k=0; k<songLine.length; k++){
            //checks if the given note is in NOTES (is a natural note)
            if(NOTES.contains(songLine[k])){
                //Increments noteCounts according to the position of the given note within NOTES
               noteCounts[NOTES.indexOf(songLine[k])]++;
            }
        }
        
        return noteCounts;
    }

    // Behavior - Finds the most repeated note within the array of notes

    // Exceptions - N/a

    // Returns - String - Returns the note that is repeated the most within the array of note Counts

    // Paramters - int[] - Array containing the amount of times that each note occurs within a line
    public static String mostCommonNote(int[] noteCounts){
        int max=0;
        int maxIndex=0;
        for(int i=0; i<noteCounts.length; i++){
            //Finds the maximum count and the corresponding index
            if(noteCounts[i]>max){
                max=noteCounts[i];
                maxIndex=i;
            }
        }
        //Uses maxIndex to return the note that corresponds to the max index
        return NOTES.substring(maxIndex, maxIndex+1);
    }
    
}