/**
 * Class to make a bird
 attack movie
 */
public class HwAnimation {

  /** The root of the scene data structure */
  private Branch sceneRoot;

  /** FrameSequencer where the animation is created */
  private FrameSequencer frames;

  /** The nodes we need to track between methods */
  private MoveBranch birdEntry, birdRetreat, hero;

  /**
   * Constructor that takes no arguments and
   * sets up the movie
   */
  public HwAnimation() {
    setUp();
  }

  /**
   * Set up all the pieces of the tree.
   */
  private void setUp(){
    Picture bird = new Picture(FileChooser.getMediaPath("egg2.jpg"));
    Picture house = new Picture(FileChooser.getMediaPath("house-blue.jpg"));
    Picture tree = new Picture(FileChooser.getMediaPath("tree-blue.jpg"));
    Picture monster = new Picture(FileChooser.getMediaPath("mscary.jpg"));

    //Make the forest
    MoveBranch forest = new MoveBranch(10,400); // at bottom
    HBranch trees = new HBranch(50); // 50 pixels between
    BlueScreenNode treenode;
    for (int i=0; i < 8; i++) { // insert 8 trees
      treenode = new BlueScreenNode(tree.scale(0.5));
      trees.addChild(treenode);
    }
    forest.addChild(trees);

    // Make the cluster of attacking "birds"
    birdEntry = new MoveBranch(10,50); // starting position
    VBranch birds = new VBranch(20); // space out by 20 pixels
    BlueScreenNode bird1 = new BlueScreenNode(bird.scale(0.5));

    birds.addChild(bird1);

    birdEntry.addChild(birds);

    // Make the cluster of retreating "birds"
    birdRetreat = new MoveBranch(400,50); // starting position
    birds = new VBranch(20); // space them out by 20 pixels
    bird1 = new BlueScreenNode(bird.scale(0.5).flip());

    birds.addChild(bird1);

    birdRetreat.addChild(birds);

    // Make the village
    MoveBranch village = new MoveBranch(300,450); // on bottom
    HBranch hhouses = new HBranch(40); // 40 pixels apart
    BlueScreenNode house1 = new BlueScreenNode(house.scale(0.25));
    BlueScreenNode house2 = new BlueScreenNode(house.scale(0.25));
    BlueScreenNode house3 = new BlueScreenNode(house.scale(0.25));
    VBranch vhouses = new VBranch(-50); // move UP 50 pixels
    BlueScreenNode house4 = new BlueScreenNode(house.scale(0.25));
    BlueScreenNode house5 = new BlueScreenNode(house.scale(0.25));
    BlueScreenNode house6 = new BlueScreenNode(house.scale(0.25));
    vhouses.addChild(house4);
    vhouses.addChild(house5);
    vhouses.addChild(house6);
    hhouses.addChild(house1);
    hhouses.addChild(house2);
    hhouses.addChild(house3);
    hhouses.addChild(vhouses); // a VBranch can be a child
    village.addChild(hhouses);

    // Make the monster
    hero = new MoveBranch(400,300);
    BlueScreenNode heronode =  new BlueScreenNode(monster.scale(0.75));
    hero.addChild(heronode);

    //Assemble the base scene
    sceneRoot = new Branch();
    sceneRoot.addChild(forest);
    sceneRoot.addChild(village);
    sceneRoot.addChild(birdEntry);
  }

  /**
   * Method to get the scene root
   * @return the sceneRoot
   */
  public Branch getSceneRoot() { return sceneRoot;}

  /**
   * Render just the first scene
   */
  public void renderScene() {
    Picture bg = new Picture(500,500);
    sceneRoot.drawOn(bg);
    bg.show();
  }

  /**
   * Render the whole animation
   */
  public void renderAnimation() {
    frames = new FrameSequencer("C:/Temp/");
    frames.show();
    Picture bg;

    // First, the nasty wolvies come closer to the poor village
    // Cue the scary music
    for (int i=0; i<25; i++) {

      // Render the frame
      bg = new Picture(500,500);
      sceneRoot.drawOn(bg);
      frames.addFrame(bg);

      // Tweak the data structure
      birdEntry.moveTo(birdEntry.getXPos()+5,birdEntry.getYPos()+10);
    }

    // Now, our hero arrives!
    this.getSceneRoot().addChild(hero);

    // Render the frame
    bg = new Picture(500,500);
    sceneRoot.drawOn(bg);
    frames.addFrame(bg);

    // Remove the birds entering, and insert the birds
    // retreating
    Branch root = this.getSceneRoot();
    root.getFirstChild().remove(birdEntry);
    root.addChild(birdRetreat);

    // Make sure that they retreat from the same place
    birdRetreat.moveTo(birdEntry.getXPos(),birdEntry.getYPos());

    // Render the frame
    bg = new Picture(500,500);
    root.drawOn(bg);
    frames.addFrame(bg);

    // Now, the cowardly birds hightail it out of there!
    // Cue the triumphant music
    for (int i=0; i<10; i++) {

      // Render the frame
      bg = new Picture(500,500);
      root.drawOn(bg);
      frames.addFrame(bg);

      // Tweak the data structure
      birdRetreat.moveTo(birdRetreat.getXPos()-10, birdRetreat.getYPos()-20);
    }
  }

  /**
   * Replay the animation
   */
  public void replay() {
    // Probably about 5 frames per second will work
    frames.replay(200);
  }

  /** Main method for testing */
  public static void main (String[] args) {
    WolfAttackMovie movie = new WolfAttackMovie();
    movie.renderAnimation();
  }
}