/* QuickMenu:  Consists of two button images (normal and highligthed) as well as a 
simple menu.  Copyright Mike Horton 1996 horton@eecs.berkeley.edu.  Permission is
granted to do use and distribute this code free of charge */


import java.awt.*;
import java.net.URL;
import java.net.MalformedURLException;

public class QuickMenu extends java.applet.Applet {
	
	Image offscreenImg;
	Graphics offscreenG;

	Image	button;		// the button graphic
	Image   button2; 	// the highlighted graphic
	Color 	bkgcolor;	// the background color
	Color   menucolor;	// the menu outline color
	MediaTracker tracker;	// media tracker to monitor loading of images
	int ybutton = 0, xbutton = 0;			// the y-location of the button-gif
	int buttonwidth, buttonheight; 
	boolean inbutton = false, inmenu = false;	// button display off and menu off
	
	QMenuLink menulinks[];  // individual menu entries with URL and text position
	String menustyle;	// menustyle, pop from up, down side
	int xmenu = 0, ymenu = 0;		// the top right corner of the menu
	int menuwidth = 0, menuheight = 0;	// the height and width of the menu
	private int numrows = 0;		// number of rows
	private int menurowspace = 20;			//  menu rowspacing
	int menuselect = -1;				// nothing selected in menu
 
	public void init() {
		offscreenImg = createImage(this.size().width, this.size().height);
		offscreenG = offscreenImg.getGraphics();

		// Get the menu entries
		while(getParameter("menu_link"+this.numrows) != null) {
			++this.numrows;
		}
		String names[] = new String[this.numrows];
		String dests[] = new String[this.numrows];
		for (int i = 0; i < this.numrows; ++i) {
			ParamString tmp_s = new ParamString(getParameter("menu_link"+i));
			names[i] = tmp_s.arg(1);
			dests[i] = tmp_s.arg(2);		
		}		 
		
		// Create menulink objects for each entry		
		menulinks = new QMenuLink[this.numrows];
		for (int i = 0; i < numrows; ++i) {
			menulinks[i] = new QMenuLink(this, names[i], dests[i],  0, 0);
		}
		
		
		// Calculate the height/width of the menu based on the length and number of menu entries		
		int curlen = 0;
		for (int i = 0; i < this.numrows; ++i) {
			curlen = menulinks[i].width(offscreenG);
			if (curlen > this.menuwidth) {
				this.menuwidth = curlen;
			}
		}
		this.menuwidth += 10;
		this.menuheight = this.numrows * this.menurowspace;
		
		
		// Load the images for the button animation
		button = getImage(getCodeBase(), getParameter("buttonup"));
		button2 = getImage(getCodeBase(), getParameter("buttondown"));
		// Create MediaTracker to make sure images load before starting
		tracker = new MediaTracker(this);
		tracker.addImage(button, 0);
		tracker.addImage(button2,0);	
		try {
			tracker.waitForAll();
		} catch (InterruptedException e) {
			System.out.println("Error waiting for images to load");
		}

		// Set the button height and width
		buttonwidth = button.getWidth(this);
		buttonheight = button.getHeight(this);

		
		// Get and set the menu position
		menustyle = new String(getParameter("menu_position"));
		if (menustyle != null) {
			if (menustyle.equals("top")) {
				this.xmenu = (int) (this.size().width / 2 - this.menuwidth / 2);
				this.ymenu = this.buttonheight - 2;
				this.xbutton = (int) (this.size().width / 2 - this.buttonwidth / 2);
				this.ybutton = 0;
			}
			else if (menustyle.equals("bottom")) {
				this.xmenu = (int) (this.size().width / 2 - this.menuwidth/ 2);
				this.ymenu = this.size().height - this.buttonheight - this.menuheight;	
				this.xbutton = (int) (this.size().width / 2 - this.buttonwidth / 2);
				this.ybutton = this.size().height - this.buttonheight - 1;
			}
			else if (menustyle.equals("side")) {
				this.xmenu = this.buttonwidth - 2;
				this.ymenu = (int) (this.size().height / 2 - this.menuheight / 2);	
				this.xbutton = 0;
				this.ybutton = (int) (this.size().height / 2 - this.buttonheight / 2);

			}
			else {
				this.xmenu = this.buttonwidth - 2;
				this.ymenu = (int) (this.size().height / 2 - this.menuheight / 2);	
				this.xbutton = 0;
				this.ybutton = (int) (this.size().height / 2 - this.buttonheight / 2);

			}
		}
		else {
			this.xmenu = this.buttonwidth - 2;
			this.ymenu = (int) (this.size().height / 2 - this.menuheight / 2);
			this.xbutton = 0;
			this.ybutton = (int) (this.size().height / 2 - this.buttonheight / 2);
		}

		// Reposition the menulinks
		for (int i = 0; i < this.numrows; ++i)	{
			menulinks[i].x = xmenu;
			menulinks[i].y = ymenu + i * menurowspace;
		}

		// Set the background colors
		if (getParameter("bkg_color") != null) {
			ParamString c = new ParamString(getParameter("bkg_color"));
			bkgcolor = new Color(Integer.parseInt(c.arg(1)), Integer.parseInt(c.arg(2)), Integer.parseInt(c.arg(3)));
		}
		else {
			// Default to white
			bkgcolor = new Color(255,255,255);
		}
		setBackground(bkgcolor);

		if (getParameter("menu_color") != null) {
			ParamString c = new ParamString(getParameter("menu_color"));
			menucolor = new Color(Integer.parseInt(c.arg(1)), Integer.parseInt(c.arg(2)), Integer.parseInt(c.arg(3)));
		}
		else {
			// Default to black
			menucolor = new Color(0,0,0);
		}
}	


	public void start() {
		inbutton = false;	
		inmenu = false;
		setBackground(bkgcolor);
		menuselect = -1;
		for (int i = 0; i < this.numrows; ++i) {
			menulinks[i].unhighlight();
		}
		repaint();
	}

	public void paint(Graphics g) {

		// Menu and button off, draw base button	
		if (!inbutton && !inmenu) {
			offscreenG.setColor(getBackground());
			offscreenG.fillRect(0,0,this.size().width, this.size().height);
			offscreenG.drawImage(button, xbutton, ybutton, this);
		}
		// draw menu links
		else {
			offscreenG.drawImage(button2, xbutton, ybutton, this);
			drawframe(offscreenG);
			for (int i = 0; i < this.numrows; ++i) {
				menulinks[i].paint(offscreenG);
			}
		}
		// copy offscreen graphics object to screen
		g.drawImage(offscreenImg,0,0,this);
	}

	public boolean mouseMove(Event evt, int x, int y) {
		// Transition into Button area, turn button & menu display on
		if ( inButton(x,y) && (inbutton == false) && (inmenu == false)) {
			inbutton = true;
			inmenu = true;
			repaint();
			return true;
		}
		// Transistion out of Button and turn off display
		else if (!inButton(x,y) && !inMenu(x,y)  && (inbutton==true)) {
			inbutton=false;
			inmenu = false;
			// Check for a highlighted menuitem and dehighlight it
			if (menuselect != -1) {
				menulinks[menuselect].unhighlight();
				menuselect = -1;
			}
			repaint();
			return true;
		}
		// Transition into menu when menu is on
		else if (inMenu(x,y) && inmenu == true) {
			// Transition into an unselected menulink
			if (inMenuLink(x,y) != menuselect) {
				if (menuselect == -1) { 
					menuselect = inMenuLink(x,y);
					menulinks[menuselect].highlight();
					repaint();
					return true;
				}
				else {
					menulinks[menuselect].unhighlight();
					menuselect = inMenuLink(x,y);
					menulinks[menuselect].highlight();
					repaint();
					return true;
				}
			}
			return true;
		}
		// Transition out of menu and turn off display
		else if (!inMenu(x,y) && inmenu == true && menuselect != -1) {
			menulinks[menuselect].unhighlight();
			menuselect = -1;
			repaint();
			return true;
		}			
		else {
			return true;
		} 
	}
	
	// Mousebutton pressed while link highlighted -> jump to link
	public boolean mouseDown(Event evt, int x, int y) { 
		if (menuselect == -1)
			return true;
		else
			menulinks[menuselect].select();
		return true;
	}

	// Draw menu outline
	void drawframe(Graphics g) {
		g.setColor(menucolor);
		g.drawRect(xmenu,ymenu,menuwidth,menuheight);
		g.drawLine(xmenu,ymenu+menurowspace, xmenu+menuwidth, ymenu+menurowspace);
	}
	
	// inButton boundary ?
	private boolean inButton(int x, int y) {
		if ((x > xbutton) && (x < xbutton + buttonwidth) && (y > ybutton) && (y < ybutton+buttonheight)) 
			return true;
		else 
			return false;
	}
	// inMenu boundary ?
	private boolean inMenu(int x, int y) {
		if ((x > xmenu) && (x < xmenu+menuwidth) && (y > ymenu) && (y < ymenu + menuheight))
			return true;
		else
			return false;
	}
	// which link selected ?  -1 is none 0 is first entry ...
	private int inMenuLink(int x, int y) {
		 int cur = (int) ((y-ymenu) / menurowspace);
		 if (cur > this.numrows-1)
			return this.numrows-1;
		 else 
			return cur;
	}
}

/* A text link within the QuickMenu.  Text is highlighted red.  */

class QMenuLink {
	
	QuickMenu outerparent;		// calling environment required for switching pages
	String name;			// Name of menulink
	URL url;			// Destination of menulink
	Color color;			// text color
	int x,y;			// x,y location of bottom left corner of menulink text
	Font f;				// menulink font
	FontMetrics fm;			// font metrics object 
	
	// Link constructor	
	QMenuLink(QuickMenu target, String name, String theURL, int x, int y) {
		this.outerparent = target;
		this.name = name;
		this.x = x;
		this.y = y;
		try { this.url = new URL(theURL); }
		catch ( MalformedURLException e) {
			System.out.println("Bad URL: " + theURL);
		}
		f = new Font("Arial", Font.BOLD, 14);
	}

	// Draw menu link text
	public void paint(Graphics g) {
		g.setFont(f);
		g.setColor(color);
		g.drawString(this.name, this.x+5, this.y+17);
	}
	public void highlight() {
		color = Color.red; 
	}

	public void unhighlight() {
		color = this.outerparent.menucolor;
	}
	// Jump to URL
	public void select() {
		outerparent.getAppletContext().showDocument(url);
	}
	public int width(Graphics g) {
		fm = g.getFontMetrics(this.f);
		return fm.stringWidth(this.name);
	}
		
}

class ParamString {

	String s;

	ParamString(String str) { 
		s = new String(str);
	}
	
	public String arg(int number) {
		int arg_cnt = 0, i =0, ind = 0;
		int tmp = s.length();
		for (i = 0; i < tmp; ++i) {
			if (s.startsWith("|",i)) { 
				arg_cnt++;
				if (arg_cnt == number)
					break;
				else
					ind = i+1;
			}	
		}
		return new String(s.substring(ind,i));
	}
}