// Author:   Zorah Fung
// Modified: Tyler Mi
// Generates random music using a music grammar

import java.io.*;
import java.util.*;
import org.jfugue.pattern.Pattern;
import org.jfugue.player.Player;
import org.jfugue.rhythm.Rhythm;

public class MusicGenerator {
   public static final boolean RHYTHM = true;
   public static final boolean MELODY = true;
   public static final boolean CHORD = true;

   public static final String FILE_NAME = "music.txt";

   public static final int REPEAT = 4;

   public static void main(String[] args) throws FileNotFoundException {
   
      GrammarSolver grammar = new GrammarSolver(readLines(FILE_NAME));
      Player player = new Player();
   
      Rhythm rhythm = new Rhythm();
      if (RHYTHM) {
         buildRhythm(grammar, rhythm);
      }
      Pattern p1 = rhythm.getPattern().setVoice(0).repeat(2);
   
      String melodyPattern = "";
      if (MELODY) {
         melodyPattern = buildPatternString(grammar, "measure");
      }
      Pattern p2 = new Pattern(melodyPattern).setInstrument("clarinet").setVoice(1);
   
      String chordPattern = "";
      if (CHORD) {
         chordPattern = buildPatternString(grammar, "chordmeasure");
      }
      Pattern p3 = new Pattern(chordPattern).setInstrument("electric_piano").setVoice(2);
   
      player.play(p1, p2, p3);
   }

   // Generates the given start symbol from the given grammar REPEAT times
   // and combines them all in a space-delimited String that is returned
   private static String buildPatternString(GrammarSolver grammar, String startSymbol) {
      String result = "";
      String[] randomPatterns = grammar.generate(startSymbol, REPEAT);
      for (String pattern: randomPatterns) {
         result += pattern + " ";
      }
      result = result.replaceAll(" - ", "");
      return result;
   }

   // Uses the given grammar to build up the rhythm to have multiple layers
   // that are chosen at random.
   private static void buildRhythm(GrammarSolver grammar, Rhythm rhythm) {
      String[] instruments = {"bassdrum", "snare", "crash", "claps"};
      for (String instr : instruments) {
         String layer = "";
         String[] randomPatterns = grammar.generate(instr, REPEAT);
         for (String pattern : randomPatterns) {
            layer += pattern;
         }
         rhythm.addLayer(layer);
      }
   }

   // Reads text from the file with the given name and returns as a List.
   // Strips empty lines and trims leading/trailing whitespace from each line.
   // pre: a file with the given name exists, throws FileNotFoundException otherwise
   public static List<String> readLines(String fileName) throws FileNotFoundException {
      List<String> lines = new ArrayList<String>();
      Scanner input = new Scanner(new File(fileName));
      while (input.hasNextLine()) {
         String line = input.nextLine().trim();
         if (line.length() > 0) {
            lines.add(line);
         }
      }
      return lines;
   }
}