package ij.plugin;
import ij.*;
import ij.gui.*;
import ij.process.*;
import ij.plugin.filter.*;
import ij.measure.Calibration;
import ij.plugin.frame.Recorder;
import ij.macro.Interpreter;

/** This plugin implements the Process/Image Calculator command.
<pre>
   // test script
   imp1 = IJ.openImage("http://imagej.nih.gov/ij/images/boats.gif")
   imp2 = IJ.openImage("http://imagej.nih.gov/ij/images/bridge.gif")
   ic = new ImageCalculator()
   imp3 = ic.run("Average create", imp1, imp2)
   imp3.show()
</pre>
*/
public class ImageCalculator implements PlugIn {

	private static String[] operators = {"Add","Subtract","Multiply","Divide", "AND", "OR", "XOR", "Min", "Max", "Average", "Difference", "Copy", "Transparent-zero"};
	private static String[] lcOperators = {"add","sub","mul","div", "and", "or", "xor", "min", "max", "ave", "diff", "copy", "zero"};
	private static int operator;
	private static String title1 = "";
	private static String title2 = "";
	private static boolean createWindow = true;
	private static boolean floatResult;
	private boolean processStack;
	
	public void run(String arg) {
		int[] wList = WindowManager.getIDList();
		if (wList==null) {
			IJ.noImage();
			return;
		}
		IJ.register(ImageCalculator.class);
		String[] titles = new String[wList.length];
		for (int i=0; i<wList.length; i++) {
			ImagePlus imp = WindowManager.getImage(wList[i]);
			if (imp!=null)
				titles[i] = imp.getTitle();
			else
				titles[i] = "";
		}
		GenericDialog gd = new GenericDialog("Image Calculator");
		String defaultItem;
		if (title1.equals(""))
			defaultItem = titles[0];
		else
			defaultItem = title1;
		gd.addChoice("Image1:", titles, defaultItem);
		gd.addChoice("Operation:", operators, operators[operator]);
		if (title2.equals(""))
			defaultItem = titles[0];
		else
			defaultItem = title2;
		gd.addChoice("Image2:", titles, defaultItem);
		//gd.addStringField("Result:", "Result", 10);
		gd.addCheckbox("Create new window", createWindow);
		gd.addCheckbox("32-bit (float) result", floatResult);
		gd.addHelp(IJ.URL+"/docs/menus/process.html#calculator");
		gd.showDialog();
		if (gd.wasCanceled())
			return;
		int index1 = gd.getNextChoiceIndex();
		title1 = titles[index1];
		operator = gd.getNextChoiceIndex();
		int index2 = gd.getNextChoiceIndex();
		//String resultTitle = gd.getNextString();
		createWindow = gd.getNextBoolean();
		floatResult = gd.getNextBoolean();		
		title2 = titles[index2];
		ImagePlus img1 = WindowManager.getImage(wList[index1]);
		ImagePlus img2 = WindowManager.getImage(wList[index2]);
		ImagePlus img3 = calculate(img1, img2, false);
		if (img3!=null) img3.show();
	}
	
	/* This method is used to implement the ImageCalculator() macro function. The 'params' argument ("add","subtract",
	"multiply","divide", "and", "or", "xor", "min", "max", "average", "difference" or "copy") specifies the operation,
	and 'img1' and 'img2' specify the operands. The  'params'  string can include up to three modifiers:
	"create" (e.g., "add create") causes the result to be stored in a new window, "32-bit" causes the result
	to be 32-bit floating-point and "stack" causes the entire stack to be processed. For example
	<pre>
       ImageCalculator ic = new ImageCalculator();
       ImagePlus imp3 = ic.calculate("divide create 32-bit", imp1, imp2);
     </pre>
      divides 'imp1' by 'imp2' and returns the result as a new 32-bit image.
	*/
	public ImagePlus run(String params, ImagePlus img1, ImagePlus img2) {
		if (img1==null || img2==null || params==null) return null;
		operator = getOperator(params);
		if (operator==-1)
			throw new IllegalArgumentException("No valid operator");
		createWindow = params.indexOf("create")!=-1;
		floatResult= params.indexOf("32")!=-1 || params.indexOf("float")!=-1;
		processStack = params.indexOf("stack")!=-1;
		return calculate(img1, img2, true);
	}
	
	/**
	* @deprecated
	* replaced by run(String,ImagePlus,ImagePlus)
	*/
	public void calculate(String params, ImagePlus img1, ImagePlus img2) {
		if (img1==null || img2==null || params==null) return;
		operator = getOperator(params);
		if (operator==-1)
			{IJ.error("Image Calculator", "No valid operator"); return;}
		createWindow = params.indexOf("create")!=-1;
		floatResult= params.indexOf("32")!=-1 || params.indexOf("float")!=-1;
		processStack = params.indexOf("stack")!=-1;
		ImagePlus img3 = calculate(img1, img2, true);
		if (img3!=null) img3.show();
	}
	
	int getOperator(String params) {
		params = params.toLowerCase();
		int op= -1;
		if  (params.indexOf("xor")!=-1)
			op = 6;
		if (op==-1) {
			for (int i=0; i<lcOperators.length; i++) {
				if (params.indexOf(lcOperators[i])!=-1) {
					op = i;
					break;
				}
			}
		}
		return op;
	}
		
	ImagePlus calculate(ImagePlus img1, ImagePlus img2, boolean apiCall) {
		ImagePlus img3 = null;
		if (img1.getCalibration().isSigned16Bit() || img2.getCalibration().isSigned16Bit())
			floatResult = true;
		if (floatResult && !(img1.getBitDepth()==32&&img2.getBitDepth()==32))
			createWindow = true;
		int size1 = img1.getStackSize();
		int size2 = img2.getStackSize();
		if (apiCall) {
			if (processStack && (size1>1||size2>1))
				img3 = doStackOperation(img1, img2);
			else
				img3 = doOperation(img1, img2);
			return img3;
		}
		boolean stackOp = false;
		if (size1>1) {
			int result = IJ.setupDialog(img1, 0);
			if (result==PlugInFilter.DONE)
				return null;
			if (result==PlugInFilter.DOES_STACKS) {
				img3 = doStackOperation(img1, img2);
				stackOp = true;
			} else
				img3 = doOperation(img1, img2);
		} else
			img3 = doOperation(img1, img2);
		if (Recorder.record) {
			String params = operators[operator];
			if (createWindow) params += " create";
			if (floatResult) params += " 32-bit";
			if (stackOp) params += " stack";
			if (Recorder.scriptMode()) {
				Recorder.recordCall("ImageCalculator", "ic = new ImageCalculator();");
				Recorder.recordCall("ImagePlus", "imp1 = WindowManager.getImage(\""+img1.getTitle()+"\");");
				Recorder.recordCall("ImagePlus", "imp2 = WindowManager.getImage(\""+img2.getTitle()+"\");");
				Recorder.recordCall("ImagePlus", "imp3 = ic.run(\""+params+"\", imp1, imp2);");
				Recorder.recordCall("imp3.show();");
			} else
				Recorder.record("imageCalculator", params, img1.getTitle(), img2.getTitle());
			Recorder.setCommand(null); // don't record run(...)
		}
		return img3;
	}

	/** img1 = img2 op img2 (e.g. img1 = img2/img1) */
	ImagePlus doStackOperation(ImagePlus img1, ImagePlus img2) {
		ImagePlus img3 = null;
		int size1 = img1.getStackSize();
		int size2 = img2.getStackSize();
		if (size1>1 && size2>1 && size1!=size2) {
			IJ.error("Image Calculator", "'Image1' and 'image2' must be stacks with the same\nnumber of slices, or 'image2' must be a single image.");
			return null;
		}
		if (createWindow) {
			img1 = duplicateStack(img1);
			if (img1==null) {
				IJ.error("Calculator", "Out of memory");
				return null;
			}
			img3 = img1;
		}
		int mode = getBlitterMode();
		ImageWindow win = img1.getWindow();
		if (win!=null)
			WindowManager.setCurrentWindow(win);
		else if (Interpreter.isBatchMode() && !createWindow && WindowManager.getImage(img1.getID())!=null)
			IJ.selectWindow(img1.getID());
		Undo.reset();
		ImageStack stack1 = img1.getStack();
		StackProcessor sp = new StackProcessor(stack1, img1.getProcessor());
		try {
			if (size2==1)
				sp.copyBits(img2.getProcessor(), 0, 0, mode);
			else
				sp.copyBits(img2.getStack(), 0, 0, mode);
		}
		catch (IllegalArgumentException e) {
			IJ.error("\""+img1.getTitle()+"\": "+e.getMessage());
			return null;
		}
		img1.setStack(null, stack1);
		if (img1.getType()!=ImagePlus.GRAY8) {
			img1.getProcessor().resetMinAndMax();
		}
		if (img3==null)
			img1.updateAndDraw();
		return img3;
	}

	ImagePlus doOperation(ImagePlus img1, ImagePlus img2) {
		ImagePlus img3 = null;
		int mode = getBlitterMode();
		ImageProcessor ip1 = img1.getProcessor();
		ImageProcessor ip2 = img2.getProcessor();
		Calibration cal1 = img1.getCalibration();
		Calibration cal2 = img2.getCalibration();
		if (createWindow)
			ip1 = createNewImage(ip1, ip2);
		else {
			ImageWindow win = img1.getWindow();
			if (win!=null)
				WindowManager.setCurrentWindow(win);
			else if (Interpreter.isBatchMode() && !createWindow && WindowManager.getImage(img1.getID())!=null)
				IJ.selectWindow(img1.getID());
			ip1.snapshot();
			Undo.setup(Undo.FILTER, img1);
		}
		if (floatResult) ip2 = ip2.convertToFloat();
		try {
			ip1.copyBits(ip2, 0, 0, mode);
		}
		catch (IllegalArgumentException e) {
			IJ.error("\""+img1.getTitle()+"\": "+e.getMessage());
			return null;
		}
		if (!(ip1 instanceof ByteProcessor))
			ip1.resetMinAndMax();
		if (createWindow) {
			img3 = new ImagePlus("Result of "+img1.getTitle(), ip1);
			img3.setCalibration(cal1);
		} else
			img1.updateAndDraw();
		return img3;
	}

	ImageProcessor createNewImage(ImageProcessor ip1, ImageProcessor ip2) {
		int width = Math.min(ip1.getWidth(), ip2.getWidth());
		int height = Math.min(ip1.getHeight(), ip2.getHeight());
		ImageProcessor ip3 = ip1.createProcessor(width, height);
		if (floatResult) {
			ip1 = ip1.convertToFloat();
			ip3 = ip3.convertToFloat();
		}
		ip3.insert(ip1, 0, 0);
		return ip3;
	}

	private int getBlitterMode() {
		int mode=0;
		switch (operator) {
			case 0: mode = Blitter.ADD; break;
			case 1: mode = Blitter.SUBTRACT; break;
			case 2: mode = Blitter.MULTIPLY; break;
			case 3: mode = Blitter.DIVIDE; break;
			case 4: mode = Blitter.AND; break;
			case 5: mode = Blitter.OR; break;
			case 6: mode = Blitter.XOR; break;
			case 7: mode = Blitter.MIN; break;
			case 8: mode = Blitter.MAX; break;
			case 9: mode = Blitter.AVERAGE; break;
			case 10: mode = Blitter.DIFFERENCE; break;
			case 11: mode = Blitter.COPY; break;
			case 12: mode = Blitter.COPY_ZERO_TRANSPARENT; break;
		}
		return mode;
	}
	
	ImagePlus duplicateStack(ImagePlus img1) {
		Calibration cal = img1.getCalibration();
		ImageStack stack1 = img1.getStack();
		int width = stack1.getWidth();
		int height = stack1.getHeight();
		int n = stack1.getSize();
		ImageStack stack2 = img1.createEmptyStack();
		try {
			for (int i=1; i<=n; i++) {
				ImageProcessor ip1 = stack1.getProcessor(i);
				ip1.resetRoi(); 
				ImageProcessor ip2 = ip1.crop();
				if (floatResult) {
					ip2.setCalibrationTable(cal.getCTable());
					ip2 = ip2.convertToFloat();
				} 
				stack2.addSlice(stack1.getSliceLabel(i), ip2);
			}
		}
		catch(OutOfMemoryError e) {
			stack2.trim();
			stack2 = null;
			return null;
		}
		ImagePlus img3 = new ImagePlus("Result of "+img1.getTitle(), stack2);
		img3.setCalibration(cal);
		if (img3.getStackSize()==n) {
			int[] dim = img1.getDimensions();
			img3.setDimensions(dim[2], dim[3], dim[4]);
			if (img1.isComposite()) {
				img3 = new CompositeImage(img3, 0);
				((CompositeImage)img3).copyLuts(img1);
			}
			if (img1.isHyperStack())
				img3.setOpenAsHyperStack(true);
		}
		return img3;
	}
	
}