package org.eclipse.swt.graphics;

import org.eclipse.swt.*;
import org.eclipse.swt.custom.*;
import org.eclipse.swt.events.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;

import com.common.util.LiteHashMap;
import com.common.util.LiteList;
import com.common.util.optimized.IntObjectHashMap;

/**
 * <pre>Attempt at writing an SWT document display that allows:
 * word wrap or no word wrap
 * document within document
 * images with text wrap & attached to top, bottom, or text position (center, left, right align?)
 * hyperlinks
 * other controls (maybe just panel?)</pre>
 */
public class StyledDocument extends Canvas {
	public static final int LEFT_WRAPPED = 0;
	public static final int RIGHT_WRAPPED = 1;
	public static final int UNWRAPPED = 2;
	
	private int width = 0;
	private String text = null;
	private String[] paragraphs = null;
	/** Assumes currently that the images are ordered first by paragraph #, then by VALIGN (TOP, then BOTTOM), then by HALIGN (HALIGN_LEFT, HALIGN_CENTER, HALIGN_RIGHT, HALIGN_LEFT_WRAPPED, then HALIGN_RIGHT_WRAPPED). */
	private ParagraphContainer[] paragraphContainers = null;
	/** Whether the metadata on the content has been reset, requiring a re-layout of the text. */
	private boolean isReset = true;
	
	private static class DocumentPart {
		public TextLayout partLayout = null;
		public int lineCount = 0;
	}//DocumentPart//
	
	private static class ComponentPart {
		public Image image = null;
		public Control control = null;
		/** The orientation of the component part, either LEFT_WRAPPED, RIGHT_WRAPPED, or UNWRAPPED (if it is the top component). */
		public int orientation = LEFT_WRAPPED;
		public int leftPadding = 0;
		public int rightPadding = 0;
		public int topPadding = 0;
		public int bottomPadding = 0;
		/** Only used with wrapped parts.  Determines how far from the preceeding component part or paragraph top before text starts wrapping and the component appears. */
		public int offset = 0;
	}//ComponentPart//
	
	private static class ParagraphContainer {
		/** A collection of TextLayout instances used in a previous rendering. */
		public LiteList layouts = new LiteList(1, 10);
		public ComponentPart top = null;
		public LiteList left = null;
		public LiteList right  = null;
		
		public void reset() {
			for(int index = layouts.getSize() - 1; index >= 0; index--) {
				((TextLayout) layouts.remove(index)).dispose();
			}//for//
		}//reset()//
	}//ParagraphContainer//
/**
 * StyledDocument constructor.
 * @param parent
 * @param style
 */
public StyledDocument(Composite parent, int style) {
	super(parent, style);
	
	addPaintListener(new PaintListener() {
		public void paintControl(PaintEvent e) {
			organize();
		}
	});
	
	addControlListener(new ControlListener() {
		public void controlResized(ControlEvent e) {
			width = getSize().x;
			reset();
		}
		public void controlMoved(ControlEvent e) {
		}
	});
}//StyledDocument()//
/**
 * 
 */
private void organize() {
	//If the control has been reset then re-layout the text.//
	if(isReset) {
		//Iterate over the paragraphs, processing them one at a time.//
		for(int paragraphIndex = 0; paragraphIndex < paragraphs.length; paragraphIndex++) {
			String subText = paragraphs[paragraphIndex];
			ParagraphContainer container = paragraphContainers[paragraphIndex];
			
			if(container.left == null && container.right == null) {
				TextLayout textLayout = new TextLayout(getDisplay());
				
				textLayout.setText(subText);
				container.layouts.add(textLayout);
			}//if//
			else {
				ComponentPart nextLeft = null;
				ComponentPart nextRight = null;
				
				while(subText != null) {
					TextLayout textLayout = new TextLayout(getDisplay());
					int lineIndex = 0;
					int height = 0;
					Rectangle lineBounds;
					
					textLayout.setText(subText);
					textLayout.setWidth(width);
					lineBounds = textLayout.getLineBounds(lineIndex);
					height += lineBounds.height;
					
					while(height)
					
					textLayout.draw(e.gc, 0, 0);
				}//while//
			}//else//
		}//for//
		
		isReset = false;
	}//if//
}//organize()//
/**
 * Adds a control to the document.
 * @param paragraphIndex The index of the paragraph the control is attached to.
 * @param orientation The orientation of the control relative to the paragraph.
 * @param control The control being added.
 * @param topPadding The padding above the control that text will not exist in.
 * @param rightPadding The padding right of the control that text will not exist in.
 * @param bottomPadding The padding below the control that text will not exist in.
 * @param leftPadding The padding left of the control that text will not exist in.
 * @param offset The offset between the control and the previous control/image or top of the paragraph that text can exist within.  This does not include padding, and is ignored if the orientation is UNWRAPPED.
 */
public void addControl(int paragraphIndex, int orientation, Control control, int topPadding, int rightPadding, int bottomPadding, int leftPadding, int offset) {
	add(paragraphIndex, orientation, control, topPadding, rightPadding, bottomPadding, leftPadding, offset);
}//addControl()//
/**
 * Adds an image to the document.
 * @param paragraphIndex The index of the paragraph the image is attached to.
 * @param orientation The orientation of the image relative to the paragraph.
 * @param control The image being added.
 * @param topPadding The padding above the image that text will not exist in.
 * @param rightPadding The padding right of the image that text will not exist in.
 * @param bottomPadding The padding below the image that text will not exist in.
 * @param leftPadding The padding left of the image that text will not exist in.
 * @param offset The offset between the image and the previous control/image or top of the paragraph that text can exist within.  This does not include padding, and is ignored if the orientation is UNWRAPPED.
 */
public void addImage(int paragraphIndex, int orientation, Image image, int topPadding, int rightPadding, int bottomPadding, int leftPadding, int offset) {
	add(paragraphIndex, orientation, image, topPadding, rightPadding, bottomPadding, leftPadding, offset);
}//addImage()//
private void add(int paragraphIndex, int orientation, Object controlOrImage, int topPadding, int rightPadding, int bottomPadding, int leftPadding, int offset) {
	if(paragraphIndex >= 0 && paragraphIndex < paragraphContainers.length) {
		ParagraphContainer container = paragraphContainers[paragraphIndex];
		ComponentPart part = new ComponentPart();
		
		if(controlOrImage instanceof Image) {
			part.image = (Image) controlOrImage;
		}//if//
		else if(controlOrImage instanceof Control) {
			part.control = (Control) controlOrImage;
		}//else if//
		
		part.topPadding = topPadding;
		part.rightPadding = rightPadding;
		part.bottomPadding = bottomPadding;
		part.leftPadding = leftPadding;
		
		switch(orientation) {
			case UNWRAPPED: {
				if(container.top == null) {
					container.top = part;
				}//if//
				else {
					throw new RuntimeException("Cannot have multiple top components.");
				}//else//
				break;
			}//case//
			case RIGHT_WRAPPED: {
				if(container.right == null) {
					container.right = new LiteList(3, 10);
				}//if//
				
				container.right.add(part);
				break;
			}//case//
			case LEFT_WRAPPED: {
				if(container.left == null) {
					container.left = new LiteList(3, 10);
				}//if//
				
				container.left.add(part);
				break;
			}//case//
		}//switch//
	}//if//
	else {
		throw new IndexOutOfBoundsException();
	}//else//
}//add()//
/**
 * Sets the text, reseting the entire control.
 * @param text The initial text for the control.
 */
public void setText(String text) {
	text = text.replace("\r\n", "\n");
	
	if(!text.equals(this.text)) {
		this.text = text;
		this.paragraphs = this.text.split("\n");
		
		//TODO: Should we remove empty paragraphs?
		
		//Cleanup old metadata.//
		reset();
		//Create a new metadata container.//
		this.paragraphContainers = new ParagraphContainer[paragraphs.length];
		
		//Setup new metadata.//
		for(int index = 0; index < this.paragraphContainers.length; index++) {
			this.paragraphContainers[index] = new ParagraphContainer();
		}//for//
	}//if//
}//setText()//
/**
 * Resets the control by clearing any cached display data.
 */
public void reset() {
	//Cleanup old metadata.//
	if(this.paragraphContainers != null) {
		for(int index = 0; index < this.paragraphContainers.length; index++) {
			this.paragraphContainers[index].reset();
		}//for//
	}//if//
	
	isReset = true;
}//reset()//
/* (non-Javadoc)
 * @see org.eclipse.swt.widgets.Widget#dispose()
 */
public void dispose() {
	reset();
	super.dispose();
}//dispose()//
public static void main(String[] args) {
	final Display display = new Display();
	final Shell shell = new Shell(display);
	StyledDocument doc = null;
	
	shell.setLayout(new FillLayout());
	doc = new StyledDocument(shell, SWT.WRAP | SWT.BORDER);

	shell.setSize(400, 400);
	shell.open();
	while (!shell.isDisposed()) {
		if (!display.readAndDispatch())
			display.sleep();
	}
	display.dispose();
}
}//StyledDocument//