MidiRepeatController.java

package org.herac.tuxguitar.player.base;

import org.herac.tuxguitar.song.models.TGDuration;
import org.herac.tuxguitar.song.models.TGMeasureHeader;
import org.herac.tuxguitar.song.models.TGSong;

public class MidiRepeatController {

  private int count;
  private int eHeader;
  private int index;
  private int lastIndex;
  private int repeatAlternative;
  private long repeatEnd;
  private long repeatMove;
  private int repeatNumber;
  private boolean repeatOpen;
  private long repeatStart;
  private int repeatStartIndex;
  private int sHeader;
  private boolean shouldPlay;
  private TGSong song;

  public MidiRepeatController(TGSong song, int sHeader, int eHeader) {
    this.song = song;
    this.sHeader = sHeader;
    this.eHeader = eHeader;
    this.count = song.countMeasureHeaders();
    this.index = 0;
    this.lastIndex = -1;
    this.shouldPlay = true;
    this.repeatOpen = true;
    this.repeatAlternative = 0;
    this.repeatStart = TGDuration.QUARTER_TIME;
    this.repeatEnd = 0;
    this.repeatMove = 0;
    this.repeatStartIndex = 0;
    this.repeatNumber = 0;
  }

  public boolean finished() {
    return (this.index >= this.count);
  }

  public int getIndex() {
    return this.index;
  }

  public long getRepeatMove() {
    return this.repeatMove;
  }

  public void process() {
    TGMeasureHeader header = this.song.getMeasureHeader(this.index);

    // Verifica si el compas esta dentro del rango.
    if ((this.sHeader != -1 && header.getNumber() < this.sHeader)
        || (this.eHeader != -1 && header.getNumber() > this.eHeader)) {
      this.shouldPlay = false;
      this.index++;
      return;
    }

    // Abro repeticion siempre para el primer compas.
    if ((this.sHeader != -1 && header.getNumber() == this.sHeader)
        || header.getNumber() == 1) {
      this.repeatStartIndex = this.index;
      this.repeatStart = header.getStart();
      this.repeatOpen = true;
    }

    // Por defecto el compas deberia sonar
    this.shouldPlay = true;

    // En caso de existir una repeticion nueva,
    // guardo el indice de el compas donde empieza una repeticion
    if (header.isRepeatOpen()) {
      this.repeatStartIndex = this.index;
      this.repeatStart = header.getStart();
      this.repeatOpen = true;

      // Si es la primer vez que paso por este compas
      // Pongo numero de repeticion y final alternativo en cero
      if (this.index > this.lastIndex) {
        this.repeatNumber = 0;
        this.repeatAlternative = 0;
      }
    } else {
      // verifico si hay un final alternativo abierto
      if (this.repeatAlternative == 0) {
        this.repeatAlternative = header.getRepeatAlternative();
      }
      // Si estoy en un final alternativo.
      // el compas solo puede sonar si el numero de repeticion coincide con el
      // numero de final alternativo.
      if (this.repeatOpen && (this.repeatAlternative > 0)
          && ((this.repeatAlternative & (1 << (this.repeatNumber))) == 0)) {
        this.repeatMove -= header.getLength();
        if (header.getRepeatClose() > 0) {
          this.repeatAlternative = 0;
        }
        this.shouldPlay = false;
        this.index++;
        return;
      }
    }

    // antes de ejecutar una posible repeticion
    // guardo el indice del ultimo compas tocado
    this.lastIndex = Math.max(this.lastIndex, this.index);

    // si hay una repeticion la hago
    if (this.repeatOpen && header.getRepeatClose() > 0) {
      if (this.repeatNumber < header.getRepeatClose()
          || (this.repeatAlternative > 0)) {
        this.repeatEnd = header.getStart() + header.getLength();
        this.repeatMove += this.repeatEnd - this.repeatStart;
        this.index = this.repeatStartIndex - 1;
        this.repeatNumber++;
      } else {
        this.repeatStart = 0;
        this.repeatNumber = 0;
        this.repeatEnd = 0;
        this.repeatOpen = false;
      }
      this.repeatAlternative = 0;
    }

    this.index++;
  }

  public boolean shouldPlay() {
    return this.shouldPlay;
  }
}