package bane;

import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import javax.swing.UIManager;

/**
 * <p>タイトル: </p>
 * <p>説明: </p>
 * <p>著作権: Copyright (c) 2003</p>
 * <p>会社名: </p>
 * @author 未入力
 * @version 1.0
 */

public class Applet1 extends Applet implements AdjustmentListener ,Runnable
{
  private boolean isStandalone = false;

  private Scrollbar scrP=new Scrollbar();
  private Scrollbar scrQ=new Scrollbar();
  private boolean drawGraph=true,drawDiagram=true;
  private boolean goFlag=false,drawInit=false,clear;
  private Thread th;

  int sw,sh;
  int hh,xofs;

 double P = 1.0;          // ダンパー初期値
 double Q = 4.0;          // バネ初期値
 int time = 0;              // 時間初期値
 int lastTime;                // 最終値
 double dh;                // 刻巾
 double rX = 0.0;          // 変移 初期値(0)
 double rY;
 double k1, k2, k3, k4, l1, l2, l3, l4;

int mx,my;
  private Label label1 = new Label();
  private Label label2 = new Label();
  private Button button1 = new Button();
  private Button clearbutton = new Button();
  private Label attlabel = new Label();
  private Label strlabel = new Label();                // 速度

  //引数値の取得
  public String getParameter(String key, String def) {
    return isStandalone ? System.getProperty(key, def) :
      (getParameter(key) != null ? getParameter(key) : def);
  }

  //アプレットのビルド
  public Applet1() {
  }

  //アプレットの初期化
  public void init() {
    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
    //binit();
    scrP.addAdjustmentListener(this);
    scrQ.addAdjustmentListener(this);
  }

  //コンポーネントの初期化
  private void jbInit() throws Exception {
    this.setLayout(null);
    scrP.setOrientation(0);
    scrP.setBounds(new Rectangle(143, 269, 92, 20));
    scrQ.setOrientation(0);
    scrQ.setValue(25);
    scrQ.setBounds(new Rectangle(296, 267, 89, 20));
    label1.setText("バネ強度");
    label1.setBounds(new Rectangle(239, 268, 52, 20));
    label2.setText("減衰度");
    label2.setBounds(new Rectangle(98, 269, 38, 20));

    this.setBackground(Color.lightGray);
    button1.setLabel("開始");
    button1.setBounds(new Rectangle(12, 266, 35, 22));
    button1.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        start_actionPerformed(e);
      }
    });
    clearbutton.setLabel("クリア");
    clearbutton.setBounds(new Rectangle(53, 266, 38, 22));
    clearbutton.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        clear_actionPerformed(e);
      }
    });
    attlabel.setText("0");
    attlabel.setBounds(new Rectangle(177, 247, 38, 17));
    strlabel.setText("12");
    strlabel.setBounds(new Rectangle(319, 246, 42, 15));
    this.add(button1, null);
    this.add(label1, null);
    this.add(label2, null);
    this.add(scrP, null);
    this.add(clearbutton, null);
    this.add(scrQ, null);
    this.add(strlabel, null);
    this.add(attlabel, null);
  }


  public void run(){
    goFlag=true;
    while(goFlag){
      repaint();
      time++;
      if(time >lastTime )goFlag=false;
      try {Thread.sleep(20);}
      catch(InterruptedException e) {}
    }
  }

  //アプレットの情報取得
  public String getAppletInfo() {
    return "アプレット情報";
  }

  //引数情報の取得
  public String[][] getParameterInfo() {
    return null;
  }


  public void adjustmentValueChanged(AdjustmentEvent e) {
    P = scrP.getValue()/50.0;
    Q = scrQ.getValue()/2.0;
    attlabel.setText(Double.toString(P));
    strlabel.setText(Double.toString(Q));
    repaint();
  }

  public void paint (Graphics g) {

    if(drawInit){
      g.setColor(Color.black);
      //g.drawString("damp = "+(float)P, 10, 260);
      //g.drawString("spring = "+Q, 150, 260);
//軸の描画
      g.drawLine(xofs,hh,sw,hh);
      g.drawLine(xofs, hh+(sh-50)/4, xofs, hh-(sh-50)/4);
      drawInit=false;
    }
    if(drawGraph){
      //for (int i = T0; i < TF; i++ ) {
      g.setColor(Color.lightGray);
      g.fillRect(0,0,sw,(sh-50)/2);


      g.setColor(Color.black);
      mx=(int)((sw-20)/4*(rX+2)+10);
      my=(sh-50)/4;
      g.fillOval(mx-15,my-15,30,30);
      drawSpring(g,10,mx-25,my);

      g.drawOval(time+xofs, (int)(hh-rX*50),1,1 );
      rkgDeq();
      //}
    }
    if(clear){
      g.setColor(Color.lightGray);
      g.fillRect(0,(sh-50)/2,sw,(sh-50)/2);
      clear=false;
    }
  }

  public void update(Graphics g) {
    paint(g);
  }

  private void drawSpring(Graphics g,int osx,int spw,int sph){
    int spx,spy;
    int pspx,pspy;
    int dy=10;

    pspx=spx=osx;pspy=spy=sph;
    double dx=spw/16.0;
    for(int i=0;i<16;i++){
      spx=(int)(osx+dx*(i+1));
      spy=spy+dy;
      if(spy ==sph-dy || spy == sph+dy) dy=-dy;
      g.drawLine(pspx,pspy,spx,spy);
      pspx=spx;pspy=spy;
      //System.out.println("drawspring:"+i+":"+dy);
    }
  }

private  void rkgDeq(){
  k1 = dh * fnk( rY );
  l1 = dh * fnl(rY, rX);
  k2 = dh * fnk(rY + l1 /2);
  l2 = dh * fnl((rY + l1 /2), (rX + k1 /2));
  k3 = dh * fnk(rY + l2 /2);
  l3 = dh * fnl((rY + l2 /2), (rX + k2 /2));
  k4 = dh * fnk(rY + l3);
  l4 = dh * fnl((rY + l3), (rX + k3));
  rX += (k1 + 2 * k2 + 2 * k3 + k4)/6;
  rY += (l1 + 2 * l2 + 2 * l3 + l4)/6;
  //System.out.println("rkg:"+rX+":"+rY+":"+dh);
}


public double fnk(double y) {
  return ( y );
}

public double fnl(double y, double x) {
  return ( -P*y-Q*x );
}

void start_actionPerformed(ActionEvent e) {
//init
  double Dt;
  int hw;
  sw = getSize().width;
  sh = getSize().height;
  int ht = (int)(sh-50);   // Disp.size
  //sh = 50;

  //g.setColor(Color.black);
  //g.fillRect(0,0,w,h);

  P = scrP.getValue()/50.0;
  Q = scrQ.getValue()/2.0;

  hw = sw/2;  //X軸0レベル
  hh = ht*3/4;  //Y軸0レベル
  lastTime = sw-20;//終了時刻
  xofs = 10; //x軸始点

  rY=0; // 初期速度
  rX=1; //初期位置
  dh=1/60.0;  //dh:刻み幅(時間）

  drawInit=true;
  repaint();
  drawInit=true;

  drawGraph=true;
  time=0;
  th=new Thread(this);
  th.start();

}

  void clear_actionPerformed(ActionEvent e) {
    clear=true;
    repaint();
  }

}