/*******************************************************************************
 * Copyright (c) 2000, 2011 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.jdt.internal.corext.fix;

import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.CoreException;

import org.eclipse.text.edits.TextEditGroup;

import org.eclipse.jdt.core.ICompilationUnit;
import org.eclipse.jdt.core.dom.AST;
import org.eclipse.jdt.core.dom.ASTNode;
import org.eclipse.jdt.core.dom.AbstractTypeDeclaration;
import org.eclipse.jdt.core.dom.AnonymousClassDeclaration;
import org.eclipse.jdt.core.dom.ClassInstanceCreation;
import org.eclipse.jdt.core.dom.FieldDeclaration;
import org.eclipse.jdt.core.dom.Javadoc;
import org.eclipse.jdt.core.dom.Modifier;
import org.eclipse.jdt.core.dom.ParameterizedType;
import org.eclipse.jdt.core.dom.PrimitiveType;
import org.eclipse.jdt.core.dom.VariableDeclarationFragment;
import org.eclipse.jdt.core.dom.rewrite.ASTRewrite;

import org.eclipse.jdt.internal.corext.codemanipulation.StubUtility;
import org.eclipse.jdt.internal.corext.dom.ASTNodeFactory;
import org.eclipse.jdt.internal.corext.fix.CompilationUnitRewriteOperationsFix.CompilationUnitRewriteOperation;
import org.eclipse.jdt.internal.corext.refactoring.structure.CompilationUnitRewrite;

import org.eclipse.jdt.ui.CodeGeneration;

/**
 * Partial implementation of a serial version correction proposal.
 *
 * @since 3.1
 */
public abstract class AbstractSerialVersionOperation extends CompilationUnitRewriteOperation {

	/** The long literal suffix */
	protected static final String LONG_SUFFIX= "L"; //$NON-NLS-1$

	/** The default serial value */
	public static final long SERIAL_VALUE= 1;

	/** The default serial id expression */
	protected static final String DEFAULT_EXPRESSION= SERIAL_VALUE + LONG_SUFFIX;

	/** The name of the serial version field */
	protected static final String NAME_FIELD= "serialVersionUID"; //$NON-NLS-1$

	/** The originally selected node */
	private final ASTNode[] fNodes;
	private final ICompilationUnit fUnit;

	protected AbstractSerialVersionOperation(final ICompilationUnit unit, final ASTNode[] node) {
		fUnit= unit;
		fNodes= node;
	}

	/**
	 * Adds an initializer to the specified variable declaration fragment.
	 * 
	 * @param fragment the variable declaration fragment to add an initializer
	 * @param declarationNode the declartion node
	 * @return false if no id could be calculated
	 */
	protected abstract boolean addInitializer(final VariableDeclarationFragment fragment, final ASTNode declarationNode);

	/**
	 * Adds the necessary linked positions for the specified fragment.
	 *
	 * @param rewrite the ast rewrite to operate on
	 * @param fragment the fragment to add linked positions to
	 * @param positionGroups the list of {@link LinkedProposalPositionGroup}s
	 */
	protected abstract void addLinkedPositions(final ASTRewrite rewrite, final VariableDeclarationFragment fragment, final LinkedProposalModel positionGroups);

	/**
	 * {@inheritDoc}
	 */
	@Override
	public void rewriteAST(CompilationUnitRewrite cuRewrite, LinkedProposalModel positionGroups) throws CoreException {
		final ASTRewrite rewrite= cuRewrite.getASTRewrite();
		VariableDeclarationFragment fragment= null;
		for (int i= 0; i < fNodes.length; i++) {
			final ASTNode node= fNodes[i];

			final AST ast= node.getAST();

			fragment= ast.newVariableDeclarationFragment();
			fragment.setName(ast.newSimpleName(NAME_FIELD));

			final FieldDeclaration declaration= ast.newFieldDeclaration(fragment);
			declaration.setType(ast.newPrimitiveType(PrimitiveType.LONG));
			declaration.modifiers().addAll(ASTNodeFactory.newModifiers(ast, Modifier.PRIVATE | Modifier.STATIC | Modifier.FINAL));

			if (!addInitializer(fragment, node))
				continue;

			if (fragment.getInitializer() != null) {

				final TextEditGroup editGroup= createTextEditGroup(FixMessages.SerialVersion_group_description, cuRewrite);
				if (node instanceof AbstractTypeDeclaration)
					rewrite.getListRewrite(node, ((AbstractTypeDeclaration) node).getBodyDeclarationsProperty()).insertAt(declaration, 0, editGroup);
				else if (node instanceof AnonymousClassDeclaration)
					rewrite.getListRewrite(node, AnonymousClassDeclaration.BODY_DECLARATIONS_PROPERTY).insertAt(declaration, 0, editGroup);
				else if (node instanceof ParameterizedType) {
					final ParameterizedType type= (ParameterizedType) node;
					final ASTNode parent= type.getParent();
					if (parent instanceof ClassInstanceCreation) {
						final ClassInstanceCreation creation= (ClassInstanceCreation) parent;
						final AnonymousClassDeclaration anonymous= creation.getAnonymousClassDeclaration();
						if (anonymous != null)
							rewrite.getListRewrite(anonymous, AnonymousClassDeclaration.BODY_DECLARATIONS_PROPERTY).insertAt(declaration, 0, editGroup);
					}
				} else
					Assert.isTrue(false);

				addLinkedPositions(rewrite, fragment, positionGroups);
			}

			final String comment= CodeGeneration.getFieldComment(fUnit, declaration.getType().toString(), NAME_FIELD, StubUtility.getLineDelimiterUsed(fUnit));
			if (comment != null && comment.length() > 0) {
				final Javadoc doc= (Javadoc) rewrite.createStringPlaceholder(comment, ASTNode.JAVADOC);
				declaration.setJavadoc(doc);
			}
		}
		if (fragment == null)
			return;

		positionGroups.setEndPosition(rewrite.track(fragment));
	}

}