package ij.plugin;
import ij.*;
import ij.process.*;
import ij.gui.*;
import ij.measure.*;
import ij.plugin.filter.RGBStackSplitter;
import ij.util.Tools;
import java.awt.*;
import java.awt.event.*;
import java.util.*;

/** Implements the Image/Stacks/Reslice command. Known shortcomings: 
    for FREELINE or POLYLINE ROI, spatial calibration is ignored: 
    the image is sampled at constant _pixel_ increments (distance 1), so 
    (if y/x aspect ratio != 1 in source image) one dimension in the output is not
    homogeneous (i.e. pixelWidth not the same everywhere).
*/
public class Slicer implements PlugIn, TextListener, ItemListener {

    private static final String[] starts = {"Top", "Left", "Bottom", "Right"};
    private static String startAt = starts[0];
    private static boolean rotate;
    private static boolean flip;
    private static boolean nointerpolate;
    private double inputZSpacing = 1.0;
    private double outputZSpacing = 1.0;
    private int outputSlices = 1;
    private boolean noRoi;
    private boolean rgb;
    private Vector fields, checkboxes;
    private Label message;
    private ImagePlus imp;
    private double gx1, gy1, gx2, gy2, gLength;

    // Variables used by getIrregularProfile and doIrregularSetup
    private int n;
    private double[] x;
    private double[] y;
    private int xbase;
    private int ybase;
    private double length;
    private double[] segmentLengths;
    private double[] dx;
    private double[] dy;

    public void run(String arg) {
         imp = WindowManager.getCurrentImage();
         if (imp==null) {
                IJ.noImage();
                return;
         }
         int stackSize = imp.getStackSize();
         Roi roi = imp.getRoi();
         int roiType = roi!=null?roi.getType():0;
         // stack required except for ROI = none or RECT
         if (stackSize<2 && roi!=null && roiType!=Roi.RECTANGLE) {
                IJ.error("Reslice...", "Stack required");
                return;
         }
         // permissible ROI types: none,RECT,*LINE
         if (roi!=null && roiType!=Roi.RECTANGLE && roiType!=Roi.LINE && roiType!=Roi.POLYLINE && roiType!=Roi.FREELINE) {
                IJ.error("Reslice...", "Line or rectangular selection required");
                return;
         }
         if (!showDialog(imp))
                return;
         long startTime = System.currentTimeMillis();
         ImagePlus imp2 = null;
         rgb = imp.getType()==ImagePlus.COLOR_RGB;
         imp2 = reslice(imp);
         if (imp2==null)
                return;
         ImageProcessor ip = imp.getProcessor();
         double min = ip.getMin();
         double max = ip.getMax();
         if (!rgb) imp2.getProcessor().setMinAndMax(min, max);
         imp2.show();
         if (noRoi)
                imp.killRoi();
        else
                imp.draw();
        IJ.showStatus(IJ.d2s(((System.currentTimeMillis()-startTime)/1000.0),2)+" seconds");
    }

    public ImagePlus reslice(ImagePlus imp) {
         ImagePlus imp2;
         Roi roi = imp.getRoi();
         int roiType = roi!=null?roi.getType():0;
         Calibration origCal = imp.getCalibration();
         if (nointerpolate) {// temporarily clear spatial calibration
                Calibration tmpCal = origCal.copy();
                tmpCal.pixelWidth = 1.0;
                tmpCal.pixelHeight = 1.0;
                tmpCal.pixelDepth = 1.0;
                imp.setCalibration(tmpCal);
                inputZSpacing = outputZSpacing = 1.0;
         }
        double zSpacing = inputZSpacing/imp.getCalibration().pixelWidth;
         if (roi==null || roiType==Roi.RECTANGLE || roiType==Roi.LINE) {
                imp2 = resliceRectOrLine(imp);
         } else {// we assert roiType==Roi.POLYLINE || roiType==Roi.FREELINE
                String status = imp.getStack().isVirtual()?"":null;
                IJ.showStatus("Reslice...");
                ImageProcessor ip2 = getSlice(imp, 0.0, 0.0, 0.0, 0.0, status);
                imp2 = new ImagePlus("Reslice of "+imp.getShortTitle(), ip2);
         }
         if (nointerpolate) // restore calibration
                imp.setCalibration(origCal);
         // create Calibration for new stack
         // start from previous cal and swap appropriate fields
         boolean horizontal = false;
         boolean vertical = false;
        if (roi==null || roiType==Roi.RECTANGLE) {
            if (startAt.equals(starts[0]) || startAt.equals(starts[2]))
                horizontal = true;
            else
                vertical = true;
        } 
        if (roi!=null && roiType==Roi.LINE) {
            Line l = (Line)roi;
            horizontal  = (l.y2-l.y1)==0;
            vertical = (l.x2-l.x1)==0;
        }
        imp2.setCalibration(imp.getCalibration());
        Calibration cal = imp2.getCalibration();
        if (horizontal) {
            cal.pixelWidth = origCal.pixelWidth;
            cal.pixelHeight = origCal.pixelDepth/zSpacing;
            cal.pixelDepth = origCal.pixelHeight*outputZSpacing;
        } else if (vertical) {
            cal.pixelWidth = origCal.pixelHeight;
            cal.pixelHeight = origCal.pixelDepth/zSpacing;
            //cal.pixelWidth = origCal.pixelDepth/zSpacing;
            //cal.pixelHeight = origCal.pixelHeight;
            cal.pixelDepth = origCal.pixelWidth*outputZSpacing;;
        } else { // oblique line, polyLine or freeline
                if (origCal.pixelHeight==origCal.pixelWidth) {
                    cal.pixelWidth=cal.pixelHeight=origCal.pixelDepth/zSpacing;
                    cal.pixelDepth = origCal.pixelWidth*outputZSpacing;
                } else {
                    cal.pixelWidth=cal.pixelHeight=cal.pixelDepth=1.0;
                    cal.setUnit("pixel");
                }
         }
         double tmp;
         if (rotate) {// if rotated flip X and Y
                tmp = cal.pixelWidth;
                cal.pixelWidth = cal.pixelHeight;
                cal.pixelHeight = tmp;
         }
         return imp2;
    }

    boolean showDialog(ImagePlus imp) {
         Calibration cal = imp.getCalibration();
         String units = cal.getUnits();
         if (cal.pixelWidth==0.0)
                cal.pixelWidth = 1.0;
         double outputSpacing = cal.pixelDepth;
         Roi roi = imp.getRoi();
         boolean line = roi!=null && roi.getType()==Roi.LINE;
         if (line)
                saveLineInfo(roi);
         GenericDialog gd = new GenericDialog("Reslice");
         gd.addNumericField("Input Z Spacing ("+units+"):", cal.pixelDepth, 3);
         gd.addNumericField("Output Z Spacing ("+units+"):", outputSpacing, 3);
         if (line)
                gd.addNumericField("Slice Count:", outputSlices, 0);
         else
                gd.addChoice("Start At:", starts, startAt);
         gd.addCheckbox("Flip Vertically", flip);
         gd.addCheckbox("Rotate 90 Degrees", rotate);
         gd.addCheckbox("Avoid Interpolation", nointerpolate);
         gd.setInsets(0, 32, 10);
         gd.addMessage("(use 1.0 for spacings)");
         gd.addMessage(getSize(cal.pixelDepth,outputSpacing,outputSlices)+"             ");
         fields = gd.getNumericFields();
         for (int i=0; i<fields.size(); i++)
                ((TextField)fields.elementAt(i)).addTextListener(this);
        checkboxes = gd.getCheckboxes();
            ((Checkbox)checkboxes.elementAt(2)).addItemListener(this);
         message = (Label)gd.getMessage();
         gd.showDialog();
         if (gd.wasCanceled())
                return false;
         inputZSpacing = gd.getNextNumber();
         if (cal.pixelDepth==0.0) cal.pixelDepth = 1.0;
         outputZSpacing = gd.getNextNumber()/cal.pixelWidth;
         if (line) {
                outputSlices = (int)gd.getNextNumber();
                imp.setRoi(roi);
         } else
                startAt = gd.getNextChoice();
         flip = gd.getNextBoolean();
         rotate = gd.getNextBoolean();
         nointerpolate = gd.getNextBoolean();
        return true;
    }

    void saveLineInfo(Roi roi) {
         Line line = (Line)roi;
         gx1 = line.x1;
         gy1 = line.y1;
         gx2 = line.x2;
         gy2 = line.y2;
         gLength = line.getRawLength();
    }

    ImagePlus resliceRectOrLine(ImagePlus imp) {
         double x1 = 0.0;
         double y1 = 0.0;
         double x2 = 0.0;
         double y2 = 0.0;
         double xInc = 0.0;
         double yInc = 0.0;
         noRoi = false;

         Roi roi = imp.getRoi();
         if (roi==null) {
                noRoi = true;
                imp.setRoi(0, 0, imp.getWidth(), imp.getHeight());
                roi = imp.getRoi();
         }
         if (roi.getType()==Roi.RECTANGLE) {
                Rectangle r = roi.getBounds();
                if (startAt.equals(starts[0])) { // top
                    x1 = r.x;
                    y1 = r.y;
                    x2 = r.x + r.width;
                    y2 = r.y;
                    xInc = 0.0;
                    yInc = outputZSpacing;
                    outputSlices =  (int)(r.height/outputZSpacing);
                } else if (startAt.equals(starts[1])) { // left
                    x1 = r.x;
                    y1 = r.y;
                    x2 = r.x;
                    y2 = r.y + r.height;
                    xInc = outputZSpacing;
                    yInc = 0.0;
                    outputSlices =  (int)(r.width/outputZSpacing);
                } else if (startAt.equals(starts[2])) { // bottom
                    x1 = r.x;
                    y1 = r.y + r.height-1;
                    x2 = r.x + r.width;
                    y2 = r.y + r.height-1;
                    xInc = 0.0;
                    yInc = -outputZSpacing;
                    outputSlices =  (int)(r.height/outputZSpacing);
                } else if (startAt.equals(starts[3])) { // right
                    x1 = r.x + r.width-1;
                    y1 = r.y;
                    x2 = r.x + r.width-1;
                    y2 = r.y + r.height;
                    xInc = -outputZSpacing;
                    yInc = 0.0;
                    outputSlices =  (int)(r.width/outputZSpacing);
                }
         } else if (roi.getType()==Roi.LINE) {
                Line line = (Line)roi;
                x1 = line.x1;
                y1 = line.y1;
                x2 = line.x2;
                y2 = line.y2;
                double dx = x2 - x1;
                double dy = y2 - y1;
                double nrm = Math.sqrt(dx*dx + dy*dy)/outputZSpacing;
                xInc = -(dy/nrm);
                yInc = (dx/nrm);
         } else
                return null;

         if (outputSlices==0) {
                IJ.error("Reslicer", "Output Z spacing ("+IJ.d2s(outputZSpacing,0)+" pixels) is too large.");
                return null;
         }
         boolean virtualStack = imp.getStack().isVirtual();
         String status = null;
         ImagePlus imp2 = null;
         ImageStack stack2 = null;
         boolean isStack = imp.getStackSize()>1;
         IJ.resetEscape();
         for (int i=0; i<outputSlices; i++) {
                if (virtualStack)
                    status = outputSlices>1?(i+1)+"/"+outputSlices+", ":"";
                ImageProcessor ip = getSlice(imp, x1, y1, x2, y2, status);
                //IJ.log(i+" "+x1+" "+y1+" "+x2+" "+y2+"   "+ip);
                if (isStack) drawLine(x1, y1, x2, y2, imp);
                if (stack2==null) {
                    stack2 = createOutputStack(imp, ip);
                    if (stack2==null || stack2.getSize()<outputSlices) return null; // out of memory
                }
                stack2.setPixels(ip.getPixels(), i+1);
                x1+=xInc; x2+=xInc; y1+=yInc; y2+=yInc;
                if (IJ.escapePressed())
                    {IJ.beep(); imp.draw(); return null;}
         }
         return new ImagePlus("Reslice of "+imp.getShortTitle(), stack2);
    }

    ImageStack createOutputStack(ImagePlus imp, ImageProcessor ip) {
         int bitDepth = imp.getBitDepth();
         int w2=ip.getWidth(), h2=ip.getHeight(), d2=outputSlices;
         int flags = NewImage.FILL_BLACK + NewImage.CHECK_AVAILABLE_MEMORY;
         ImagePlus imp2 = NewImage.createImage("temp", w2, h2, d2, bitDepth, flags);
         if (imp2!=null && imp2.getStackSize()==d2)
                IJ.showStatus("Reslice... (press 'Esc' to abort)");
         if (imp2==null)
                return null;
         else {
                ImageStack stack2 = imp2.getStack();
                stack2.setColorModel(ip.getColorModel());
                return stack2;
         }
    }

    ImageProcessor getSlice(ImagePlus imp, double x1, double y1, double x2, double y2, String status) {
         Roi roi = imp.getRoi();
         int roiType = roi!=null?roi.getType():0;
         ImageStack stack = imp.getStack();
         int stackSize = stack.getSize();
         ImageProcessor ip,ip2=null;
         float[] line = null;
         boolean ortho = (int)x1==x1&&(int)y1==y1&&x1==x2||y1==y2;
        //boolean vertical = x1==x2 && (roi==null||roiType==Roi.RECTANGLE);
        //if (rotate) vertical = !vertical;
         for (int i=0; i<stackSize; i++) {
                ip = stack.getProcessor(flip?stackSize-i:i+1);
                if (roiType==Roi.POLYLINE || roiType==Roi.FREELINE)
                    line = getIrregularProfile(roi, ip);
                else if (ortho)
                    line = getOrthoLine(ip, (int)x1, (int)y1, (int)x2, (int)y2, line);
                else
                    line = getLine(ip, x1, y1, x2, y2, line);
                if (rotate) {
                    if (i==0) ip2 = ip.createProcessor(stackSize, line.length);
                    putColumn(ip2, i, 0, line, line.length);
                } else {
                    if (i==0) ip2 = ip.createProcessor(line.length, stackSize);
                    putRow(ip2, 0, i, line, line.length);
                }
                if (status!=null) IJ.showStatus("Slicing: "+status +i+"/"+stackSize);
         }
         Calibration cal = imp.getCalibration();
         double zSpacing = inputZSpacing/cal.pixelWidth;
         if (zSpacing!=1.0) {
                ip2.setInterpolate(true);
                if (rotate)
                    ip2 = ip2.resize((int)(stackSize*zSpacing), line.length);
                else
                    ip2 = ip2.resize(line.length, (int)(stackSize*zSpacing));
         }
         return ip2;
    }

    public void putRow(ImageProcessor ip, int x, int y, float[] data, int length) {
         if (rgb) {
                for (int i=0; i<length; i++)
                    ip.putPixel(x++, y, Float.floatToIntBits(data[i]));
         } else {
                for (int i=0; i<length; i++)
                    ip.putPixelValue(x++, y, data[i]);
         }
    }

    public void putColumn(ImageProcessor ip, int x, int y, float[] data, int length) {
         if (rgb) {
                for (int i=0; i<length; i++)
                    ip.putPixel(x, y++, Float.floatToIntBits(data[i]));
         } else {
                for (int i=0; i<length; i++)
                    ip.putPixelValue(x, y++, data[i]);
         }
    }

    float[] getIrregularProfile(Roi roi, ImageProcessor ip) {
         if (x==null)
                doIrregularSetup(roi);
         float[] values = new float[(int)length];
         double leftOver = 1.0;
         double distance = 0.0;
         int index;
         double oldx=xbase, oldy=ybase;
         for (int i=0; i<n; i++) {
                double len = segmentLengths[i];
                if (len==0.0)
                    continue;
                double xinc = dx[i]/len;
                double yinc = dy[i]/len;
                double start = 1.0-leftOver;
                double rx = xbase+x[i]+start*xinc;
                double ry = ybase+y[i]+start*yinc;
                double len2 = len - start;
                int n2 = (int)len2;
                //double d=0;;
                //IJ.write("new segment: "+IJ.d2s(xinc)+" "+IJ.d2s(yinc)+" "+IJ.d2s(len)+" "+IJ.d2s(len2)+" "+IJ.d2s(n2)+" "+IJ.d2s(leftOver));
                for (int j=0; j<=n2; j++) {
                    index = (int)distance+j;
                    if (index<values.length) {
                         if (rgb) {
                                int rgbPixel = ((ColorProcessor)ip).getInterpolatedRGBPixel(rx, ry);
                                values[index] = Float.intBitsToFloat(rgbPixel&0xffffff);
                         } else
                                values[index] = (float)ip.getInterpolatedValue(rx, ry);
                    }
                    //d = Math.sqrt((rx-oldx)*(rx-oldx)+(ry-oldy)*(ry-oldy));
                    //IJ.write(IJ.d2s(rx)+" "+IJ.d2s(ry)+"   "+IJ.d2s(d));
                    //oldx = rx; oldy = ry;
                    rx += xinc;
                    ry += yinc;
                }
                distance += len;
                leftOver = len2 - n2;
         }

         return values;

    }

    void doIrregularSetup(Roi roi) {
         n = ((PolygonRoi)roi).getNCoordinates();
         int[] ix = ((PolygonRoi)roi).getXCoordinates();
         int[] iy = ((PolygonRoi)roi).getYCoordinates();
         x = new double[n];
         y = new double[n];
         for (int i=0; i<n; i++) {
                x[i] = ix[i];
                y[i] = iy[i];
         }
         if (roi.getType()==Roi.FREELINE) {
                // smooth line
                for (int i=1; i<n-1; i++) {
                    x[i] = (x[i-1] + x[i] + x[i+1])/3.0+0.5;
                    y[i] = (y[i-1] + y[i] + y[i+1])/3.0+0.5;
                }
         }
         Rectangle r = roi.getBounds();
         xbase = r.x;
         ybase = r.y;
         length = 0.0;
         double segmentLength;
         double xdelta, ydelta;
         segmentLengths = new double[n];
         dx = new double[n];
         dy = new double[n];
         for (int i=0; i<(n-1); i++) {
                xdelta = x[i+1] - x[i];
                ydelta = y[i+1] - y[i];
                segmentLength = Math.sqrt(xdelta*xdelta+ydelta*ydelta);
                length += segmentLength;
                segmentLengths[i] = segmentLength;
                dx[i] = xdelta;
                dy[i] = ydelta;
         }
    }

    private float[] getLine(ImageProcessor ip, double x1, double y1, double x2, double y2, float[] data) {
         double dx = x2-x1;
         double dy = y2-y1;
         int n = (int)Math.round(Math.sqrt(dx*dx + dy*dy));
         if (data==null)
                data = new float[n];
         double xinc = dx/n;
         double yinc = dy/n;
         double rx = x1;
         double ry = y1;
         for (int i=0; i<n; i++) {
                if (rgb) {
                    int rgbPixel = ((ColorProcessor)ip).getInterpolatedRGBPixel(rx, ry);
                    data[i] = Float.intBitsToFloat(rgbPixel&0xffffff);
                } else
                    data[i] = (float)ip.getInterpolatedValue(rx, ry);
                rx += xinc;
                ry += yinc;
         }
         return data;
    }

    private float[] getOrthoLine(ImageProcessor ip, int x1, int y1, int x2, int y2, float[] data) {
         int dx = x2-x1;
         int dy = y2-y1;
         int n = Math.max(Math.abs(dx), Math.abs(dy));
         if (data==null) data = new float[n];
         int xinc = dx/n;
         int yinc = dy/n;
         int rx = x1;
         int ry = y1;
         for (int i=0; i<n; i++) {
                if (rgb) {
                    int rgbPixel = ((ColorProcessor)ip).getPixel(rx, ry);
                    data[i] = Float.intBitsToFloat(rgbPixel&0xffffff);
                } else
                    data[i] = (float)ip.getPixelValue(rx, ry);
                rx += xinc;
                ry += yinc;
         }
         return data;
    }

    void drawLine(double x1, double y1, double x2, double y2, ImagePlus imp) {
         ImageCanvas ic = imp.getCanvas();
         if (ic==null) return;
         Graphics g = ic.getGraphics();
         g.setColor(Roi.getColor());
         g.setXORMode(Color.black);
         g.drawLine(ic.screenX((int)(x1+0.5)), ic.screenY((int)(y1+0.5)), ic.screenX((int)(x2+0.5)), ic.screenY((int)(y2+0.5)));
    }

    public void textValueChanged(TextEvent e) {
        updateSize();
    }

    public void itemStateChanged(ItemEvent e) {
        Checkbox cb = (Checkbox)checkboxes.elementAt(2);
        nointerpolate = cb.getState();
        updateSize();
    }

    void updateSize() {
         double inSpacing = Tools.parseDouble(((TextField)fields.elementAt(0)).getText(),0.0);
         double outSpacing = Tools.parseDouble(((TextField)fields.elementAt(1)).getText(),0.0);
         int count = 0;
         boolean lineSelection = fields.size()==3;
         if (lineSelection) {
                count = (int)Tools.parseDouble(((TextField)fields.elementAt(2)).getText(), 0.0);
                if (count>0) makePolygon(count, outSpacing);
         }
         String size = getSize(inSpacing, outSpacing, count);
         message.setText(size);
    }

    String getSize(double inSpacing, double outSpacing, int count) {
         int size = getOutputStackSize(inSpacing, outSpacing, count);
         int mem = getAvailableMemory();
         String available = mem!=-1?" ("+mem+"MB free)":"";
         if (message!=null)
                message.setForeground(mem!=-1&&size>mem?Color.red:Color.black);
         if (size>0)
                return size+"MB"+available;
         else
                return "<1MB"+available;
    }

    void makePolygon(int count, double outSpacing) {
         int[] x = new int[4];
         int[] y = new int[4];
         x[0] = (int)gx1;
         y[0] = (int)gy1;
         x[1] = (int)gx2;
         y[1] = (int)gy2;
         double dx = gx2 - gx1;
         double dy = gy2 - gy1;
         double nrm = Math.sqrt(dx*dx + dy*dy)/outSpacing;
         double xInc = -(dy/nrm);
         double yInc = (dx/nrm);
         x[2] = x[1] + (int)(xInc*count);
         y[2] = y[1] + (int)(yInc*count);
         x[3] = x[0] + (int)(xInc*count);
         y[3] = y[0] + (int)(yInc*count);
         imp.setRoi(new PolygonRoi(x, y, 4, PolygonRoi.FREEROI));
    }

    int getOutputStackSize(double inSpacing, double outSpacing, int count) {
        Roi roi = imp.getRoi();
        int width = imp.getWidth();
        int height = imp.getHeight();
        if (roi!=null) {
            Rectangle r = roi.getBounds();
            width = r.width;
            width = r.height;
        }
        int type = roi!=null?roi.getType():0;
        int stackSize = imp.getStackSize();
        double size = 0.0;
        if (type==Roi.RECTANGLE) {
            size = width*height*stackSize;
            if (outSpacing>0&&!nointerpolate) size *= inSpacing/outSpacing;
        } else
            size = gLength*count*stackSize;
        int bits = imp.getBitDepth();
        switch (bits) {
            case 16: size*=2; break;
            case 24: case 32: size*=4; break;
        }
        return (int)Math.round(size/1048576.0);
    }

    int getAvailableMemory() {
         long max = IJ.maxMemory();
         if (max==0) return -1;
         long inUse = IJ.currentMemory();
         long available = max - inUse;
         return (int)((available+524288L)/1048576L);
    }
}