Copyright (c) 2000, 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) 2000, 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.internal.core.dom.rewrite;

import java.util.HashSet;
import java.util.IdentityHashMap;
import java.util.Map;
import java.util.Set;

import org.eclipse.jdt.core.dom.AST;
import org.eclipse.jdt.core.dom.ASTNode;
import org.eclipse.jdt.core.dom.Block;
import org.eclipse.jdt.core.dom.FieldDeclaration;
import org.eclipse.jdt.core.dom.Modifier;
import org.eclipse.jdt.core.dom.ParameterizedType;
import org.eclipse.jdt.core.dom.TryStatement;
import org.eclipse.jdt.core.dom.VariableDeclarationExpression;
import org.eclipse.jdt.core.dom.VariableDeclarationStatement;

import org.eclipse.jdt.internal.core.dom.rewrite.RewriteEventStore.CopySourceInfo;

/**
 *
 */
@SuppressWarnings({"rawtypes", "unchecked"})
public final class NodeInfoStore {
	private AST ast;

	private Map placeholderNodes;
	private Set collapsedNodes;

	public NodeInfoStore(AST ast) {
		super();
		this.ast= ast;
		this.placeholderNodes= null;
		this.collapsedNodes= null;
	}

	
Marks a node as a placehoder for a plain string content. The type of the node should correspond to the
code's code content.
Params:
placeholder – The placeholder node that acts for the string content.
code – The string content./**
	 * Marks a node as a placehoder for a plain string content. The type of the node should correspond to the
	 * code's code content.
	 * @param placeholder The placeholder node that acts for the string content.
	 * @param code The string content.
	 */
	public final void markAsStringPlaceholder(ASTNode placeholder, String code) {
		StringPlaceholderData data= new StringPlaceholderData();
		data.code= code;
		setPlaceholderData(placeholder, data);
	}

	
Marks a node as a copy or move target. The copy target represents a copied node at the target (copied) site.
Params:
target – The node at the target site. Can be a placeholder node but also the source node itself.
copySource – The info at the source site./**
	 * Marks a node as a copy or move target. The copy target represents a copied node at the target (copied) site.
	 * @param target The node at the target site. Can be a placeholder node but also the source node itself.
	 * @param copySource The info at the source site.
	 */
	public final void markAsCopyTarget(ASTNode target, CopySourceInfo copySource) {
		CopyPlaceholderData data= new CopyPlaceholderData();
		data.copySource= copySource;
		setPlaceholderData(target, data);
	}

	
Creates a placeholder node of the given type. null if the type is not supported
Params:
nodeType – Type of the node to create. Use the type constants in NodeInfoStore.
Returns:
Returns a place holder node./**
	 * Creates a placeholder node of the given type. <code>null</code> if the type is not supported
	 * @param nodeType Type of the node to create. Use the type constants in {@link NodeInfoStore}.
	 * @return Returns a place holder node.
	 */
	public final ASTNode newPlaceholderNode(int nodeType) {
		try {
			ASTNode node= this.ast.createInstance(nodeType);
			switch (node.getNodeType()) {
				case ASTNode.FIELD_DECLARATION:
					((FieldDeclaration) node).fragments().add(this.ast.newVariableDeclarationFragment());
					break;
				case ASTNode.MODIFIER:
					((Modifier) node).setKeyword(Modifier.ModifierKeyword.ABSTRACT_KEYWORD);
					break;
				case ASTNode.TRY_STATEMENT :
					((TryStatement) node).setFinally(this.ast.newBlock()); // have to set at least a finally block to be legal code
					break;
				case ASTNode.VARIABLE_DECLARATION_EXPRESSION :
					((VariableDeclarationExpression) node).fragments().add(this.ast.newVariableDeclarationFragment());
					break;
				case ASTNode.VARIABLE_DECLARATION_STATEMENT :
					((VariableDeclarationStatement) node).fragments().add(this.ast.newVariableDeclarationFragment());
					break;
				case ASTNode.PARAMETERIZED_TYPE :
					((ParameterizedType) node).typeArguments().add(this.ast.newWildcardType());
					break;
			}
			return node;
		} catch (IllegalArgumentException e) {
			return null;
		}
 	}


	// collapsed nodes: in source: use one node that represents many; to be used as
	// copy/move source or to replace at once.
	// in the target: one block node that is not flattened.

	public Block createCollapsePlaceholder() {
		Block placeHolder= this.ast.newBlock();
		if (this.collapsedNodes == null) {
			this.collapsedNodes= new HashSet();
		}
		this.collapsedNodes.add(placeHolder);
		return placeHolder;
	}

	public boolean isCollapsed(ASTNode node) {
		if (this.collapsedNodes != null) {
			return this.collapsedNodes.contains(node);
		}
		return false;
	}

	public Object getPlaceholderData(ASTNode node) {
		if (this.placeholderNodes != null) {
			return this.placeholderNodes.get(node);
		}
		return null;
	}

	private void setPlaceholderData(ASTNode node, PlaceholderData data) {
		if (this.placeholderNodes == null) {
			this.placeholderNodes= new IdentityHashMap();
		}
		this.placeholderNodes.put(node, data);
	}

	static class PlaceholderData {
		// base class
	}

	protected static final class CopyPlaceholderData extends PlaceholderData {
		public CopySourceInfo copySource;
		@Override
		public String toString() {
			return "[placeholder " + this.copySource +"]";  //$NON-NLS-1$//$NON-NLS-2$
		}
	}

	protected static final class StringPlaceholderData extends PlaceholderData {
		public String code;
		@Override
		public String toString() {
			return "[placeholder string: " + this.code +"]"; //$NON-NLS-1$ //$NON-NLS-2$
		}
	}

	/**
	 *
	 */
	public void clear() {
		this.placeholderNodes= null;
		this.collapsedNodes= null;
	}
}