/*******************************************************************************
 * Copyright (c) 2004 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.wst.css.core.internal.formatter;


import org.eclipse.jface.text.IRegion;
import org.eclipse.wst.css.core.cleanup.CSSCleanupStrategy;
import org.eclipse.wst.css.core.document.ICSSNode;
import org.eclipse.wst.css.core.parser.CSSRegionContexts;
import org.eclipse.wst.css.core.preferences.CSSPreferenceHelper;
import org.eclipse.wst.sse.core.IndexedRegion;
import org.eclipse.wst.sse.core.text.IStructuredDocument;
import org.eclipse.wst.sse.core.text.IStructuredDocumentRegion;
import org.eclipse.wst.sse.core.text.ITextRegion;


/**
 * 
 */
public class StyleDeclarationFormatter extends DefaultCSSSourceFormatter {

	private static StyleDeclarationFormatter instance;

	/**
	 * 
	 */
	StyleDeclarationFormatter() {
		super();
	}

	/**
	 * 
	 */
	protected void formatBefore(ICSSNode node, ICSSNode child, String toAppend, StringBuffer source, IRegion exceptFor) {
		CSSCleanupStrategy stgy = getCleanupStrategy(node);

		ICSSNode prev = (child != null) ? child.getPreviousSibling() : node.getLastChild();
		int start = (prev != null) ? ((IndexedRegion) prev).getEndOffset() : 0;
		int end = (child != null) ? ((IndexedRegion) child).getStartOffset() : 0;

		// check no child
		if (child == null && prev == null)
			return;

		CSSPreferenceHelper mgr = CSSPreferenceHelper.getInstance();
		if (start > 0 && start < end) { // format source
			IStructuredDocument structuredDocument = node.getOwnerDocument().getModel().getStructuredDocument();
			// get meaning regions
			CompoundRegion[] regions = null;
			if (exceptFor == null)
				regions = getRegionsWithoutWhiteSpaces(structuredDocument, new FormatRegion(start, end - start), stgy);
			else {
				String pickupType = CSSRegionContexts.CSS_DECLARATION_DELIMITER;
				if (prev == null || child == null)
					pickupType = null;
				regions = getRegions(structuredDocument, new FormatRegion(start, end - start), exceptFor, pickupType);
			}
			// extract source
			for (int i = 0; i < regions.length; i++) {
				appendSpaceBefore(node, regions[i], source);
				source.append(decoratedRegion(regions[i], 0, stgy)); // must
																		// be
																		// comments
			}
		}
		else if (prev != null && child != null) { // generate source :
													// between two
													// declarations
			source.append(";");//$NON-NLS-1$
		}
		else if (prev == null) { // generate source : before the first
									// declaration
			org.eclipse.wst.css.core.util.RegionIterator it = null;
			if (end > 0) {
				IStructuredDocument structuredDocument = node.getOwnerDocument().getModel().getStructuredDocument();
				it = new org.eclipse.wst.css.core.util.RegionIterator(structuredDocument, end - 1);
			}
			else {
				int pos = getChildInsertPos(node);
				if (pos >= 0) {
					IStructuredDocument structuredDocument = node.getOwnerDocument().getModel().getStructuredDocument();
					it = new org.eclipse.wst.css.core.util.RegionIterator(structuredDocument, pos - 1);
				}
			}
			if (it != null) {
				int limit = ((IndexedRegion) ((node.getParentNode() != null) ? node.getParentNode() : node)).getStartOffset();
				while (it.hasPrev()) {
					ITextRegion curReg = it.prev();
					if (curReg.getType() == CSSRegionContexts.CSS_LBRACE || curReg.getType() == CSSRegionContexts.CSS_DECLARATION_DELIMITER)
						break;
					if (curReg.getType() != CSSRegionContexts.CSS_S && curReg.getType() != CSSRegionContexts.CSS_COMMENT) {
						source.append(";");//$NON-NLS-1$
						break;
					}
					if (it.getStructuredDocumentRegion().getStartOffset(curReg) <= limit)
						break;
				}
			}
		}
		else if (child == null) { // generate source : after the last
									// declaration
			org.eclipse.wst.css.core.util.RegionIterator it = null;
			if (start > 0) {
				IStructuredDocument structuredDocument = node.getOwnerDocument().getModel().getStructuredDocument();
				it = new org.eclipse.wst.css.core.util.RegionIterator(structuredDocument, start);
			}
			else {
				int pos = getChildInsertPos(node);
				if (pos >= 0) {
					IStructuredDocument structuredDocument = node.getOwnerDocument().getModel().getStructuredDocument();
					it = new org.eclipse.wst.css.core.util.RegionIterator(structuredDocument, pos);
				}
			}
			if (it != null) {
				int limit = ((IndexedRegion) ((node.getParentNode() != null) ? node.getParentNode() : node)).getEndOffset();
				while (it.hasNext()) {
					ITextRegion curReg = it.next();
					if (curReg.getType() == CSSRegionContexts.CSS_RBRACE || curReg.getType() == CSSRegionContexts.CSS_DECLARATION_DELIMITER)
						break;
					if (curReg.getType() != CSSRegionContexts.CSS_S && curReg.getType() != CSSRegionContexts.CSS_COMMENT) {
						source.append(";");//$NON-NLS-1$
						break;
					}
					if (limit <= it.getStructuredDocumentRegion().getEndOffset(curReg))
						break;
				}
			}
		}
		if (child == null) {
			if (((IndexedRegion) node).getEndOffset() <= 0) {
				// get next region
				int pos = getChildInsertPos(node);
				CompoundRegion toAppendRegion = null;
				if (pos >= 0) {
					IStructuredDocument structuredDocument = node.getOwnerDocument().getModel().getStructuredDocument();
					IStructuredDocumentRegion flatNode = structuredDocument.getRegionAtCharacterOffset(pos);
					toAppendRegion = new CompoundRegion(flatNode, flatNode.getRegionAtCharacterOffset(pos));
				}
				appendDelimBefore(node.getParentNode(), toAppendRegion, source);
			}
		}
		else if ((prev != null || ((IndexedRegion) node).getEndOffset() <= 0)) {
			if (mgr.isOnePropertyPerLine() && (node.getOwnerDocument() != node || !mgr.isProhibitWrapOnAttr()))
				appendDelimBefore(node, null, source);
			else if (prev != null || node.getOwnerDocument() != node)
				appendSpaceBefore(node, toAppend, source);
		}
	}

	/**
	 * 
	 */
	protected void formatBefore(ICSSNode node, ICSSNode child, IRegion region, String toAppend, StringBuffer source) {
		CSSCleanupStrategy stgy = getCleanupStrategy(node);

		IStructuredDocument structuredDocument = node.getOwnerDocument().getModel().getStructuredDocument();
		CompoundRegion[] regions = getRegionsWithoutWhiteSpaces(structuredDocument, region, stgy);
		CompoundRegion[] outside = getOutsideRegions(structuredDocument, region);
		CSSPreferenceHelper mgr = CSSPreferenceHelper.getInstance();
		for (int i = 0; i < regions.length; i++) {
			if (i != 0 || needS(outside[0]))
				appendSpaceBefore(node, regions[i], source);
			source.append(decoratedRegion(regions[i], 0, stgy)); // must be
																	// comments
		}
		if (needS(outside[1])) {
			if (((IndexedRegion) child).getStartOffset() == region.getOffset() + region.getLength() && mgr.isOnePropertyPerLine() && (node.getOwnerDocument() != node || !mgr.isProhibitWrapOnAttr())) {
				appendDelimBefore(node, null, source);
			}
			else
				appendSpaceBefore(node, toAppend, source);
		}
	}

	/**
	 * Insert the method's description here.
	 */
	public int getChildInsertPos(ICSSNode node) {
		if (node == null)
			return -1;
		int pos = super.getChildInsertPos(node);
		if (pos < 0) {
			CSSSourceGenerator formatter = getParentFormatter(node);
			return (formatter != null) ? formatter.getChildInsertPos(node.getParentNode()) : -1;
		}
		else
			return pos;
	}

	/**
	 * 
	 */
	public synchronized static StyleDeclarationFormatter getInstance() {
		if (instance == null)
			instance = new StyleDeclarationFormatter();
		return instance;
	}

	/**
	 * 
	 * @return int
	 * @param node
	 *            org.eclipse.wst.css.core.model.interfaces.ICSSNode
	 * @param insertPos
	 *            int
	 */
	public int getLengthToReformatAfter(ICSSNode node, int insertPos) {
		if (node == null)
			return 0;
		IndexedRegion nnode = (IndexedRegion) node;
		if (insertPos < 0 || !nnode.contains(insertPos)) {
			if (node.getParentNode() != null && nnode.getEndOffset() <= 0) {
				CSSSourceGenerator pntFormatter = getParentFormatter(node);
				if (pntFormatter != null)
					return pntFormatter.getLengthToReformatAfter(node.getParentNode(), insertPos);
			}
			return 0;
		}
		return super.getLengthToReformatAfter(node, insertPos);
	}

	/**
	 * 
	 * @return int
	 * @param node
	 *            org.eclipse.wst.css.core.model.interfaces.ICSSNode
	 * @param insertPos
	 *            int
	 */
	public int getLengthToReformatBefore(ICSSNode node, int insertPos) {
		if (node == null)
			return 0;
		IndexedRegion nnode = (IndexedRegion) node;
		if (insertPos <= 0 || !nnode.contains(insertPos - 1)) {
			if (node.getParentNode() != null && nnode.getEndOffset() <= 0) {
				CSSSourceGenerator pntFormatter = getParentFormatter(node);
				if (pntFormatter != null)
					return pntFormatter.getLengthToReformatBefore(node.getParentNode(), insertPos);
			}
			return 0;
		}
		return super.getLengthToReformatBefore(node, insertPos);
	}
}