Copyright (c) 2004, 2013 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2004, 2013 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jdt.core.dom;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;

import org.eclipse.text.edits.MultiTextEdit;
import org.eclipse.text.edits.TextEdit;

import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.TextUtilities;

import org.eclipse.jdt.core.JavaCore;
import org.eclipse.jdt.core.dom.SimplePropertyDescriptor;
import org.eclipse.jdt.core.dom.StructuralPropertyDescriptor;
import org.eclipse.jdt.core.dom.rewrite.TargetSourceRangeComputer;
import org.eclipse.jdt.internal.compiler.parser.RecoveryScannerData;
import org.eclipse.jdt.internal.core.dom.rewrite.ASTRewriteAnalyzer;
import org.eclipse.jdt.internal.core.dom.rewrite.LineInformation;
import org.eclipse.jdt.internal.core.dom.rewrite.ListRewriteEvent;
import org.eclipse.jdt.internal.core.dom.rewrite.NodeInfoStore;
import org.eclipse.jdt.internal.core.dom.rewrite.NodeRewriteEvent;
import org.eclipse.jdt.internal.core.dom.rewrite.RewriteEventStore;
import org.eclipse.jdt.internal.core.dom.rewrite.RewriteEventStore.CopySourceInfo;
import org.eclipse.jdt.internal.core.dom.rewrite.RewriteEventStore.PropertyLocation;

Internal class: not intended to be used by client.
When AST modifications recording is enabled, all changes are recorded by this class.
/**
 * Internal class: not intended to be used by client.
 * When AST modifications recording is enabled, all changes are recorded by this class.
 */
@SuppressWarnings({"rawtypes", "unchecked"})
class InternalASTRewrite extends NodeEventHandler {

	
root node for the rewrite: Only nodes under this root are accepted /** root node for the rewrite: Only nodes under this root are accepted */
	private CompilationUnit root;

	protected final RewriteEventStore eventStore;
	protected final NodeInfoStore nodeStore;
	
ASTNode clone -> ASTNode original /** ASTNode clone -> ASTNode original */ 
	protected final Hashtable clonedNodes;

	int cloneDepth = 0;

	
Constructor
Params:
root – root node of the recorded ast./**
	 * Constructor
	 * @param root root node of the recorded ast.
	 */
	public InternalASTRewrite(CompilationUnit root) {
		this.root = root;
		this.eventStore = new RewriteEventStore();
		this.nodeStore = new NodeInfoStore(root.getAST());
		this.clonedNodes = new Hashtable();
	}

	
Performs the rewrite: The rewrite events are translated to the corresponding in text changes. The given options can be null in which case the global options JavaCore.getOptions() will be used. 
Params:
document – Document which describes the code of the AST that is passed in in the
constructor. This document is accessed read-only.
options – the given options
Throws:
IllegalArgumentException – if the rewrite fails
Returns:
Returns the edit describing the text changes./**
	 * Performs the rewrite: The rewrite events are translated to the corresponding in text changes.
	 * The given options can be null in which case the global options {@link JavaCore#getOptions() JavaCore.getOptions()}
	 * will be used.
	 *
	 * @param document Document which describes the code of the AST that is passed in in the
	 * constructor. This document is accessed read-only.
	 * @param options the given options
	 * @throws IllegalArgumentException if the rewrite fails
	 * @return Returns the edit describing the text changes.
	 */
	public TextEdit rewriteAST(IDocument document, Map options) {
		TextEdit result = new MultiTextEdit();

		final CompilationUnit rootNode = getRootNode();
		if (rootNode != null) {
			TargetSourceRangeComputer xsrComputer = new TargetSourceRangeComputer() {
				
This implementation of TargetSourceRangeComputer.computeSourceRange(ASTNode) is specialized to work in the case of internal AST rewriting, where the original AST has been modified from its original form. This means that one cannot trust that the root of the given node is the compilation unit. /**
				 * This implementation of
				 * {@link TargetSourceRangeComputer#computeSourceRange(ASTNode)}
				 * is specialized to work in the case of internal AST rewriting, where the
				 * original AST has been modified from its original form. This means that
				 * one cannot trust that the root of the given node is the compilation unit.
				 */
				@Override
				public SourceRange computeSourceRange(ASTNode node) {
					int extendedStartPosition = rootNode.getExtendedStartPosition(node);
					int extendedLength = rootNode.getExtendedLength(node);
					return new SourceRange(extendedStartPosition, extendedLength);
				}
			};
			char[] content= document.get().toCharArray();
			LineInformation lineInfo= LineInformation.create(document);
			String lineDelim= TextUtilities.getDefaultLineDelimiter(document);
			List comments= rootNode.getCommentList();

			Map currentOptions = options == null ? JavaCore.getOptions() : options;
			ASTRewriteAnalyzer visitor = new ASTRewriteAnalyzer(content, lineInfo, lineDelim, result, this.eventStore, this.nodeStore, comments, currentOptions, xsrComputer, (RecoveryScannerData)rootNode.getStatementsRecoveryData());
			rootNode.accept(visitor);
		}
		return result;
	}

	private  void markAsMoveOrCopyTarget(ASTNode node, ASTNode newChild) {
		if (this.cloneDepth == 0) {
			while (node != null && this.clonedNodes.containsKey(node)) {
				/*
				 * A modified node cannot be considered as cloned any more.
				 * we can't copy the original formatting/comments and at the same time modify the node.
				 * 
				 * Workaround for https://bugs.eclipse.org/405699 is to remove such nodes from clonedNodes
				 * and instead mark all children as cloned (or skip them if they are not in clonedNodes).
				 */
				ASTNode orig = (ASTNode) this.clonedNodes.remove(node);
				if (orig != null) {
					List properties = node.structuralPropertiesForType();
					for (int i= 0; i < properties.size(); i++) {
						StructuralPropertyDescriptor property = (StructuralPropertyDescriptor) properties.get(i);
						Object child = node.getStructuralProperty(property);
						if (child instanceof ASTNode) {
							markAsMoveOrCopyTarget(node, (ASTNode) child);
						} else if (child instanceof List) {
							List children = (List) child;
							for (int j= 0; j < children.size(); j++) {
								ASTNode clonedChild = (ASTNode) children.get(j);
								markAsMoveOrCopyTarget(node, clonedChild);
							}
						}
					}
				}
				
				node = node.getParent();
			}
		}
		
		ASTNode source = (ASTNode)this.clonedNodes.get(newChild);
		if(source != null) {
			if(this.cloneDepth == 0) {
				PropertyLocation propertyLocation = this.eventStore.getPropertyLocation(source, RewriteEventStore.ORIGINAL);
				CopySourceInfo sourceInfo =
					this.eventStore.markAsCopySource(
						propertyLocation.getParent(),
						propertyLocation.getProperty(),
						source,
						false);
				this.nodeStore.markAsCopyTarget(newChild, sourceInfo);
			}
		} else if((newChild.getFlags() & ASTNode.ORIGINAL) != 0) {
			PropertyLocation propertyLocation = this.eventStore.getPropertyLocation(newChild, RewriteEventStore.ORIGINAL);
			CopySourceInfo sourceInfo =
				this.eventStore.markAsCopySource(
					propertyLocation.getParent(),
					propertyLocation.getProperty(),
					newChild,
					true);
			this.nodeStore.markAsCopyTarget(newChild, sourceInfo);
		}
	}

	private CompilationUnit getRootNode() {
		return this.root;
	}

	@Override
	public String toString() {
		StringBuffer buf = new StringBuffer();
		buf.append("Events:\n"); //$NON-NLS-1$
		buf.append(this.eventStore.toString());
		return buf.toString();
	}

	@Override
	void preValueChangeEvent(ASTNode node, SimplePropertyDescriptor property) {
		// force event creation
		getNodeEvent(node, property);
	}

	@Override
	void postValueChangeEvent(ASTNode node, SimplePropertyDescriptor property) {
		NodeRewriteEvent event = getNodeEvent(node, property);
		event.setNewValue(node.getStructuralProperty(property));
	}

	@Override
	void preAddChildEvent(ASTNode node, ASTNode child,	StructuralPropertyDescriptor property) {
		if(property.isChildProperty()) {
			NodeRewriteEvent event = getNodeEvent(node, property);
			event.setNewValue(child);
			if(child != null) {
				markAsMoveOrCopyTarget(node, child);
			}
		} else if(property.isChildListProperty()) {
			// force event creation
			getListEvent(node, property);
		}
	}

	@Override
	void postAddChildEvent(ASTNode node, ASTNode child,	StructuralPropertyDescriptor property) {
		if(property.isChildListProperty()) {

			ListRewriteEvent event = getListEvent(node, property);
			List list = (List)node.getStructuralProperty(property);
			int i = list.indexOf(child);
			int s = list.size();
			int index;
			if(i + 1 < s) {
				ASTNode nextNode = (ASTNode)list.get(i + 1);
				index = event.getIndex(nextNode, ListRewriteEvent.NEW);
			} else {
				index = -1;
			}
			event.insert(child, index);
			if(child != null) {
				markAsMoveOrCopyTarget(node, child);
			}
		}
	}

	@Override
	void preRemoveChildEvent(ASTNode node, ASTNode child, StructuralPropertyDescriptor property) {
		if(property.isChildProperty()) {
			NodeRewriteEvent event = getNodeEvent(node, property);
			event.setNewValue(null);
		} else if(property.isChildListProperty()) {
			ListRewriteEvent event = getListEvent(node, property);
			int i = event.getIndex(child, ListRewriteEvent.NEW);
			NodeRewriteEvent nodeEvent = (NodeRewriteEvent)event.getChildren()[i];
			if(nodeEvent.getOriginalValue() == null) {
				event.revertChange(nodeEvent);
			} else {
				nodeEvent.setNewValue(null);
			}
		}
	}

	@Override
	void preReplaceChildEvent(ASTNode node, ASTNode child, ASTNode newChild, StructuralPropertyDescriptor property) {
		if(property.isChildProperty()) {
			NodeRewriteEvent event = getNodeEvent(node, property);
			event.setNewValue(newChild);
			if(newChild != null) {
				markAsMoveOrCopyTarget(node, newChild);
			}
		} else if(property.isChildListProperty()) {
			ListRewriteEvent event = getListEvent(node, property);
			int i = event.getIndex(child, ListRewriteEvent.NEW);
			NodeRewriteEvent nodeEvent = (NodeRewriteEvent)event.getChildren()[i];
			nodeEvent.setNewValue(newChild);
			if(newChild != null) {
				markAsMoveOrCopyTarget(node, newChild);
			}
		}
	}


	@Override
	void preCloneNodeEvent(ASTNode node) {
		this.cloneDepth++;
	}


	@Override
	void postCloneNodeEvent(ASTNode node, ASTNode clone) {
		if(node.ast == this.root.ast && clone.ast == this.root.ast) {
			if((node.getFlags() & ASTNode.ORIGINAL) != 0) {
				this.clonedNodes.put(clone, node);
			} else {
				// node can be a cloned node
				Object original = this.clonedNodes.get(node);
				if(original != null) {
					this.clonedNodes.put(clone, original);
				}
			}
		}
		this.cloneDepth--;
	}

	private NodeRewriteEvent getNodeEvent(ASTNode node, StructuralPropertyDescriptor property) {
		return this.eventStore.getNodeEvent(node, property, true);
	}

	private ListRewriteEvent getListEvent(ASTNode node, StructuralPropertyDescriptor property) {
		return this.eventStore.getListEvent(node, property, true);
	}
}