/*******************************************************************************
 * Copyright (c) 2008, 2016 xored software, Inc. 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:
 *     xored software, Inc. - initial API and Implementation (Alex Panchenko)
 *******************************************************************************/
package org.eclipse.dltk.ruby.testing.internal;

import java.io.File;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.URL;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.dltk.compiler.util.Util;
import org.eclipse.dltk.launching.InterpreterConfig;
import org.eclipse.dltk.launching.ScriptLaunchConfigurationConstants;
import org.eclipse.dltk.testing.AbstractTestingEngine;
import org.eclipse.dltk.testing.DLTKTestingPlugin;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.osgi.util.NLS;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.osgi.framework.Bundle;

public abstract class AbstractRubyTestingEngine extends AbstractTestingEngine {

	protected static final String RUBY_TESTING_PORT = "RUBY_TESTING_PORT"; //$NON-NLS-1$
	protected static final String RUBY_TESTING_PATH = "RUBY_TESTING_PATH"; //$NON-NLS-1$

	protected static final String RUNNER_PATH = "/testing/"; //$NON-NLS-1$

	protected Bundle getBundle() {
		return RubyTestingPlugin.getDefault().getBundle();
	}

	protected File getRunnerFile(final Bundle bundle, final String runnerPath,
			final String runnerName) throws CoreException {
		URL runnerScript = bundle.getEntry(runnerPath + runnerName);
		if (runnerScript == null) {
			final String msg = NLS.bind(Messages.Delegate_runnerNotFound,
					runnerName);
			throw new CoreException(new Status(IStatus.ERROR,
					RubyTestingPlugin.PLUGIN_ID, msg, null));
		}
		try {
			return Util.toFile(runnerScript);
		} catch (IOException e) {
			final String msg = NLS.bind(
					Messages.Delegate_errorExtractingRunner, runnerName);
			throw new CoreException(new Status(IStatus.ERROR,
					RubyTestingPlugin.PLUGIN_ID, msg, e));
		}
	}

	protected boolean isDevelopmentMode(InterpreterConfig config,
			String runnerName) {
		return config.getScriptFilePath() != null
				&& config.getScriptFilePath().lastSegment().equals(runnerName);
	}

	/**
	 * Returns a free port number on localhost, or -1 if unable to find a free
	 * port.
	 * 
	 * @return a free port number or -1
	 */
	private static int findFreePort() {
		ServerSocket socket = null;
		try {
			socket = new ServerSocket(0);
			return socket.getLocalPort();
		} catch (IOException e) {
		} finally {
			if (socket != null) {
				try {
					socket.close();
				} catch (IOException e) {
				}
			}
		}
		return -1;
	}

	protected int allocatePort() throws CoreException {
		int port = findFreePort();
		if (port == -1) {
			informAndAbort(
					"No socket available", //$NON-NLS-1$
					null,
					ScriptLaunchConfigurationConstants.ERR_NO_SOCKET_AVAILABLE);
		}
		return port;
	}

	protected void informAndAbort(String message, Throwable exception, int code)
			throws CoreException {
		IStatus status = new Status(IStatus.INFO, RubyTestingPlugin.PLUGIN_ID,
				code, message, exception);
		if (showStatusMessage(status)) {
			// Status message successfully shown
			// -> Abort with INFO exception
			// -> Worker.run() will not write to log
			throw new CoreException(status);
		} else {
			// Status message could not be shown
			// -> Abort with original exception
			// -> Will write WARNINGs and ERRORs to log
			throw new CoreException(new Status(IStatus.ERROR,
					RubyTestingPlugin.PLUGIN_ID, code, message, exception));
		}
	}

	protected boolean showStatusMessage(final IStatus status) {
		final boolean[] success = new boolean[] { false };
		getDisplay().syncExec(new Runnable() {
			@Override
			public void run() {
				Shell shell = DLTKTestingPlugin.getActiveWorkbenchShell();
				if (shell == null)
					shell = getDisplay().getActiveShell();
				if (shell != null) {
					MessageDialog.openInformation(shell,
							"Problems Launching Unit Tests", //$NON-NLS-1$
							status.getMessage());
					success[0] = true;
				}
			}
		});
		return success[0];
	}

	private Display getDisplay() {
		Display display;
		display = Display.getCurrent();
		if (display == null)
			display = Display.getDefault();
		return display;
	}

	/**
	 * @param info
	 * @param string
	 * @return
	 */
	protected static IStatus createStatus(int severity, String message) {
		return new Status(severity, RubyTestingPlugin.PLUGIN_ID, message);
	}

}