package ij.text;
import ij.util.Java2;
import java.awt.*;
import java.awt.event.*;

class TextCanvas extends Canvas {

    TextPanel tp;
    Font fFont;
    FontMetrics fMetrics;
    Graphics gImage;
    Image iImage;
    boolean antialiased;

    TextCanvas(TextPanel tp) {
        this.tp = tp;
        addMouseListener(tp);
        addMouseMotionListener(tp);
        addKeyListener(tp);
        addMouseWheelListener(tp);
    }

    public void setBounds(int x, int y, int width, int height) {
        super.setBounds(x, y, width, height);
        tp.adjustVScroll();
        tp.adjustHScroll();
        iImage = null;
    }

    public void update(Graphics g) {
        paint(g);
    }
  
    public void paint(Graphics g) {
        if (tp==null || g==null) return;
        Dimension d = getSize();
        int iWidth = d.width;
        int iHeight = d.height;
        
        if (iWidth<=0 || iHeight<=0) return;
        g.setColor(Color.lightGray);
        if (iImage==null)
            makeImage(iWidth,iHeight);
        if (tp.iRowHeight==0 || (tp.iColWidth.length>0 && tp.iColWidth[0]==0&&tp.iRowCount>0)) {
            tp.iRowHeight=fMetrics.getHeight()+2;
            for (int i=0; i<tp.iColCount; i++)
                calcAutoWidth(i);
            tp.adjustHScroll();
            tp.adjustVScroll();
        }
        gImage.setColor(Color.white);
        gImage.fillRect(0,0,iWidth,iHeight);
        if (tp.headings)
            drawColumnLabels(iWidth);
        int y=tp.iRowHeight+1-tp.iY;
        int j=0;
        while (y<tp.iRowHeight+1) {
            j++;
            y+=tp.iRowHeight;
        }
        tp.iFirstRow=j;
        y=tp.iRowHeight+1;
        for (;y<iHeight && j<tp.iRowCount; j++,y+=tp.iRowHeight) {
            int x=-tp.iX;
            for (int i=0;i<tp.iColCount;i++) {
                if (i>=tp.iColWidth.length) break;
                int w = tp.iColWidth[i];
                Color b=Color.white,t=Color.black;
                if (j>=tp.selStart && j<=tp.selEnd) {
                    int w2 = w;
                    if (tp.iColCount==1)
                        w2 = iWidth;
                    b=Color.black;
                    t=Color.white;
                    gImage.setColor(b);
                    gImage.fillRect(x,y,w2-1,tp.iRowHeight);
                }
                gImage.setColor(t);
                char[] chars = getChars(i,j);
                if (chars!=null)
                    gImage.drawChars(chars,0,chars.length,x+2,y+tp.iRowHeight-5);
                x+=w;
            }
        }
        if (iImage!=null)
            g.drawImage(iImage,0,0,null);
    }
  
    void makeImage(int iWidth, int iHeight) {
        iImage=createImage(iWidth, iHeight);
        if (gImage!=null)
            gImage.dispose();
        gImage=iImage.getGraphics();
        gImage.setFont(fFont);
        Java2.setAntialiasedText(gImage, antialiased);
        if(fMetrics==null)
            fMetrics=gImage.getFontMetrics();
    }

    void drawColumnLabels(int iWidth) {
        gImage.setColor(Color.darkGray);
        gImage.drawLine(0,tp.iRowHeight,iWidth,tp.iRowHeight);
        int x=-tp.iX;
        for (int i=0; i<tp.iColCount; i++) {
            int w=tp.iColWidth[i];
            gImage.setColor(Color.lightGray);
            gImage.fillRect(x+1,0,w,tp.iRowHeight);
            gImage.setColor(Color.black);
            if (tp.sColHead[i]!=null)
                gImage.drawString(tp.sColHead[i],x+2,tp.iRowHeight-5);
            if (tp.iColCount>0) {
                gImage.setColor(Color.darkGray);
                gImage.drawLine(x+w-1,0,x+w-1,tp.iRowHeight-1);
                gImage.setColor(Color.white);
                gImage.drawLine(x+w,0,x+w,tp.iRowHeight-1);
            }
            x+=w;
        }
        gImage.setColor(Color.lightGray);
        gImage.fillRect(0,0,1,tp.iRowHeight);
        gImage.fillRect(x+1,0,iWidth-x,tp.iRowHeight);
        //gImage.drawLine(0,0,0,iRowHeight-1);
        gImage.setColor(Color.darkGray);
        gImage.drawLine(0,0,iWidth,0);
    }
    
    synchronized char[] getChars(int column, int row) {
        if (tp==null || tp.vData==null)
            return null;
        if (row>=tp.vData.size())
            return null;
        char[] chars = row<tp.vData.size()?(char[])(tp.vData.elementAt(row)):null;
        if (chars==null || chars.length==0)
            return null;
        
        if (tp.iColCount==1)
            return chars;
        
        int start = 0;
        int tabs = 0;
        int length = chars.length;
        
        while (column>tabs) {
            if (chars[start]=='\t')
                tabs++;
            start++;
            if (start>=length)
                return null;
        };
        if (start<0 || start>=chars.length) {
            System.out.println("start="+start+", chars.length="+chars.length);          
            return null;
        }
        if (chars[start]=='\t')
            return null;
        
        int end = start;
        while (chars[end]!='\t' && end<(length-1))
            end++;
        if (chars[end]=='\t')
            end--;
            
        char[] chars2 = new char[end-start+1];
        for (int i=0,j=start; i<chars2.length; i++,j++) {
            chars2[i] = chars[j];
        } 
        return chars2;
    }
    
    void calcAutoWidth(int column) {
        if (tp.sColHead==null || column>=tp.iColWidth.length || gImage==null)
            return;
        if (fMetrics==null)
            fMetrics=gImage.getFontMetrics();
        int w=15;
        int maxRows = 20;
        if (column==0 && tp.sColHead[0].equals(" "))
            w += 5;
        else {
            char[] chars = tp.sColHead[column].toCharArray();
            w = Math.max(w,fMetrics.charsWidth(chars,0,chars.length));
        }
        int rowCount = Math.min(tp.iRowCount, maxRows);
        for (int row=0; row<rowCount; row++) {
            char[] chars = getChars(column,row);
            if (chars!=null)
                w = Math.max(w,fMetrics.charsWidth(chars,0,chars.length));
        }
        //System.out.println("calcAutoWidth: "+column+"  "+tp.iRowCount);
        char[] chars = tp.iRowCount>0?getChars(column, tp.iRowCount-1):null;
        if (chars!=null)
            w = Math.max(w,fMetrics.charsWidth(chars,0,chars.length));
        if (column<tp.iColWidth.length)
            tp.iColWidth[column] = w+15;
    }

}