Copyright (c) 2018 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
    Red Hat Inc. - copied over to jdt.core.manipulation and renamed
/*******************************************************************************
 * Copyright (c) 2018 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
 *     Red Hat Inc. - copied over to jdt.core.manipulation and renamed
 *******************************************************************************/
package org.eclipse.jdt.internal.corext.fix;

import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;

import org.eclipse.text.edits.TextEditGroup;

import org.eclipse.ltk.core.refactoring.GroupCategory;
import org.eclipse.ltk.core.refactoring.GroupCategorySet;

import org.eclipse.jdt.core.ICompilationUnit;
import org.eclipse.jdt.core.dom.ASTNode;
import org.eclipse.jdt.core.dom.CompilationUnit;
import org.eclipse.jdt.core.dom.ITypeBinding;
import org.eclipse.jdt.core.dom.Type;
import org.eclipse.jdt.core.dom.rewrite.ImportRewrite;
import org.eclipse.jdt.core.dom.rewrite.ImportRewrite.ImportRewriteContext;
import org.eclipse.jdt.core.dom.rewrite.ImportRewrite.TypeLocation;
import org.eclipse.jdt.core.refactoring.CompilationUnitChange;

import org.eclipse.jdt.internal.core.manipulation.JavaManipulationPlugin;
import org.eclipse.jdt.internal.corext.codemanipulation.ContextSensitiveImportRewriteContext;
import org.eclipse.jdt.internal.corext.refactoring.structure.CompilationUnitRewrite;

public class CompilationUnitRewriteOperationsFixCore extends AbstractFix {

	public abstract static class CompilationUnitRewriteOperation {

		public abstract void rewriteAST(CompilationUnitRewrite cuRewrite, LinkedProposalModelCore linkedModel) throws CoreException;

		protected Type importType(final ITypeBinding toImport, final ASTNode accessor, ImportRewrite imports, final CompilationUnit compilationUnit, TypeLocation location) {
			ImportRewriteContext importContext= new ContextSensitiveImportRewriteContext(compilationUnit, accessor.getStartPosition(), imports);
			return imports.addImport(toImport, compilationUnit.getAST(), importContext, location);
		}

		protected TextEditGroup createTextEditGroup(String label, CompilationUnitRewrite rewrite) {
			if (label.length() > 0) {
				return rewrite.createCategorizedGroupDescription(label, new GroupCategorySet(new GroupCategory(label, label, label)));
			} else {
				return rewrite.createGroupDescription(label);
			}
		}

		public String getAdditionalInfo() {
			return null;
		}
	}

	private final CompilationUnitRewriteOperation[] fOperations;
	private final CompilationUnit fCompilationUnit;
	protected LinkedProposalModelCore fLinkedProposalModel;

	public CompilationUnitRewriteOperationsFixCore(String name, CompilationUnit compilationUnit, CompilationUnitRewriteOperation operation) {
		this(name, compilationUnit, new CompilationUnitRewriteOperation[] { operation });
		Assert.isNotNull(operation);
	}

	public CompilationUnitRewriteOperationsFixCore(String name, CompilationUnit compilationUnit, CompilationUnitRewriteOperation[] operations) {
		super(name);
		Assert.isNotNull(operations);
		Assert.isLegal(operations.length > 0);
		fCompilationUnit= compilationUnit;
		fOperations= operations;
		fLinkedProposalModel= new LinkedProposalModelCore();
	}

	@Override
	public LinkedProposalModelCore getLinkedPositionsCore() {
		if (!fLinkedProposalModel.hasLinkedPositions())
			return null;

		return fLinkedProposalModel;
	}

	@Override
	public CompilationUnitChange createChange(IProgressMonitor progressMonitor) throws CoreException {
		CompilationUnitRewrite cuRewrite= new CompilationUnitRewrite((ICompilationUnit)fCompilationUnit.getJavaElement(), fCompilationUnit);

		fLinkedProposalModel.clear();
		for (int i= 0; i < fOperations.length; i++) {
			CompilationUnitRewriteOperation operation= fOperations[i];
			operation.rewriteAST(cuRewrite, fLinkedProposalModel);
		}

		CompilationUnitChange result= cuRewrite.createChange(getDisplayString(), true, null);
		if (result == null)
			throw new CoreException(new Status(IStatus.ERROR, JavaManipulationPlugin.getPluginId(), Messages.format(FixMessages.CompilationUnitRewriteOperationsFix_nullChangeError, getDisplayString())));

		return result;
	}

	@Override
	public String getAdditionalProposalInfo(){
		StringBuilder sb= new StringBuilder();
		for (int i= 0; i < fOperations.length; i++) {
			CompilationUnitRewriteOperation operation= fOperations[i];
			String info= operation.getAdditionalInfo();
			if (info != null)
				sb.append(info);
		}

		if (sb.length() == 0)
			return null;

		return sb.toString();
	}

}