package ij.plugin;
import ij.*;
import ij.gui.*;
import ij.process.*;
import ij.measure.*;
import java.awt.*;

/** This plugin implements the commands in the Image/Zoom submenu. */
public class Zoom implements PlugIn{

    /** 'arg' must be "in", "out", "100%" or "orig". */
    public void run(String arg) {
        ImagePlus imp = WindowManager.getCurrentImage();
        if (imp==null)
            {IJ.noImage(); return;}
        ImageCanvas ic = imp.getCanvas();
        if (ic==null) return;
        Point loc = ic.getCursorLoc();
        int x = ic.screenX(loc.x);
        int y = ic.screenY(loc.y);
        if (arg.equals("in")) {
            ic.zoomIn(x, y);
            if (ic.getMagnification()<=1.0) imp.repaintWindow();
        } else if (arg.equals("out")) {
            ic.zoomOut(x, y);
            if (ic.getMagnification()<1.0) imp.repaintWindow();
        } else if (arg.equals("orig"))
            ic.unzoom();
        else if (arg.equals("100%"))
            ic.zoom100Percent();
        else if (arg.equals("to"))
            zoomToSelection(imp, ic);
        else if (arg.equals("max")) {
            ImageWindow win = imp.getWindow();
            win.setBounds(win.getMaximumBounds());
            win.maximize();
        }
    }
    
    void zoomToSelection(ImagePlus imp, ImageCanvas ic) {
        Roi roi = imp.getRoi();
        ic.unzoom();
        if (roi==null) return;
        Rectangle w = imp.getWindow().getBounds();
        Rectangle r = roi.getBounds();
        double mag = ic.getMagnification();
        int marginw = (int)((w.width - mag * imp.getWidth()));
        int marginh = (int)((w.height - mag * imp.getHeight()));
        int x = r.x+r.width/2;
        int y = r.y+r.height/2;
        mag = ic.getHigherZoomLevel(mag);
        while(r.width*mag<w.width - marginw && r.height*mag<w.height - marginh) {
            ic.zoomIn(ic.screenX(x), ic.screenY(y));
            double cmag = ic.getMagnification();
            if (cmag==32.0) break;
            mag = ic.getHigherZoomLevel(cmag);
            w = imp.getWindow().getBounds();
        }
    }
    
}