/*******************************************************************************
 * Copyright (c) 2000, 2016 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.releng.tools;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IResourceProxyVisitor;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;


public class MapFile {
	
	/**
	 * @deprecated As of 3.7, replaced by {@link #isMapFile(IFile)}
	 */
	@Deprecated
	public static final String MAP_FILE_EXTENSION = "map"; //$NON-NLS-1$
	private static final String MAP_FILE_NAME_ENDING = '.' + MAP_FILE_EXTENSION;
	
	protected IFile file;
	protected MapEntry[] entries;
	
	public MapFile(IFile aFile) throws CoreException {
		file = aFile;
		loadEntries();
	}
	
	public IFile getFile(){
		return file;
	}
	
	protected void loadEntries() throws CoreException {
		List<MapEntry> list = new ArrayList<>();		

		try (InputStream inputStream = file.getContents();){
			
			BufferedReader aReader = new BufferedReader(new InputStreamReader(
					inputStream));
			String aLine = aReader.readLine();
			while (aLine != null) {
				if (isMapLine(aLine)) {
					list.add(new MapEntry(aLine));
				}
				aLine = aReader.readLine();
			}
		} catch (IOException e) {
			throw new CoreException(new Status(IStatus.ERROR, RelEngPlugin.ID, 0, "An I/O Error occurred process map file " + file.getFullPath().toString(), e));
		}

		this.entries = list.toArray(new MapEntry[list.size()]);
	}
	
	private boolean isMapLine(String line) {
		if (line.trim().length() == 0) return false;
		if (line.startsWith("!")) return false;
		return true;
	}
	
	public boolean contains(IProject project){
		for(int j = 0;j < entries.length; j++){
			if (entries[j].isMappedTo(project)){
				return true;
			}
		}
		return false;
	}

	public MapEntry getMapEntry(IProject project) {
		for(int j = 0;j < entries.length; j++){
			if (entries[j].isMappedTo(project)){
				return entries[j];
			}
		}
		return null;
	}

	public IProject[] getAccessibleProjects() {
		Set<IProject> list = new HashSet<>();
		IProject[] projects = ResourcesPlugin.getWorkspace().getRoot().getProjects();
		if(entries == null || entries.length ==0) return null;
		for (int i = 0; i < projects.length; i++) {
			IProject project = projects[i];
			if (project.isAccessible()) {
				for (int j = 0; j < entries.length; j++){
					if (entries[j].isMappedTo(project)) {
						list.add(project);
					}
				}
			}
		}
		return list.toArray(new IProject[list.size()]);
	}

	public String getName() {
		return file.getName();
	}

	/**
	 * Finds all map files in the workspace.
	 * 
	 * @param resource the resource for which to find the map files
	 * @return an array of all map file for the given resource
	 * @throws CoreException if something goes wrong
	 * @since 3.7
	 */
	public static MapFile[] findAllMapFiles(IResource resource) throws CoreException {
		final ArrayList<MapFile> mapFiles = new ArrayList<>();
		IResourceProxyVisitor visitor= resourceProxy -> {
			if (!resourceProxy.isAccessible())
				return false;

			int type= resourceProxy.getType();
			if (type == IResource.PROJECT)
				return RelEngPlugin.isShared((IProject)resourceProxy.requestResource());

			if (type == IResource.FILE && resourceProxy.getName().endsWith(MAP_FILE_NAME_ENDING))
				mapFiles.add(new MapFile((IFile)resourceProxy.requestResource()));

			return true;
		};
		
		resource.accept(visitor,IResource.NONE);
		
		return mapFiles.toArray(new MapFile[mapFiles.size()]);
	}

	public static boolean isMapFile(IFile aFile){
		return MapFile.MAP_FILE_EXTENSION.equals(aFile.getFileExtension());
	}

}