/*******************************************************************************
 * 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.ant.internal.ui.antsupport.inputhandler;

import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.input.DefaultInputHandler;
import org.apache.tools.ant.input.InputRequest;
import org.eclipse.ant.internal.core.IAntCoreConstants;
import org.eclipse.ant.internal.ui.antsupport.AntSupportMessages;
import org.eclipse.jface.dialogs.IInputValidator;
import org.eclipse.jface.dialogs.InputDialog;
import org.eclipse.jface.window.Window;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Display;

/**
 * The default input handler when using Ant within Eclipse. This is the class that will respond to {@literal <input>} requests from within an Ant
 * build file. If the build is occurring in Ant 1.6.0 and the -noinput option has been specified this input handler will fail.
 */
public class AntInputHandler extends DefaultInputHandler {

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.apache.tools.ant.input.InputHandler#handleInput(org.apache.tools.ant.input.InputRequest)
	 */
	@Override
	public void handleInput(InputRequest request) throws BuildException {
		if (System.getProperty("eclipse.ant.noInput") != null) { //$NON-NLS-1$
			throw new BuildException(AntSupportMessages.AntInputHandler_5);
		}
		BuildException[] problem = new BuildException[1];
		Runnable runnable = getHandleInputRunnable(request, problem);
		Display.getDefault().syncExec(runnable);
		if (problem[0] != null) {
			throw problem[0];
		}
	}

	protected Runnable getHandleInputRunnable(final InputRequest request, final BuildException[] problem) {
		return () -> {
			String prompt = getPrompt(request);
			String title = AntSupportMessages.AntInputHandler_Ant_Input_Request_1;
			IInputValidator validator = new IInputValidator() {
				private boolean fFirstValidation = true;

				@Override
				public String isValid(String value) {
					request.setInput(value);
					if (request.isInputValid()) {
						return null;
					}
					if (fFirstValidation) {
						fFirstValidation = false;
						return IAntCoreConstants.EMPTY_STRING;
					}
					return AntSupportMessages.AntInputHandler_Invalid_input_2;
				}
			};

			String initialValue = null;
			try {
				request.getClass().getMethod("getDefaultValue", new Class[0]); //$NON-NLS-1$
				initialValue = request.getDefaultValue();
			}
			catch (SecurityException e1) {
				// do nothing
			}
			catch (NoSuchMethodException e2) {
				// pre Ant 1.7.0
			}
			InputDialog dialog = new InputDialog(null, title, prompt, initialValue, validator) {
				@Override
				protected int getShellStyle() {
					return super.getShellStyle() | SWT.RESIZE;
				}
			};
			if (dialog.open() != Window.OK) {
				problem[0] = new BuildException(AntSupportMessages.AntInputHandler_Unable_to_respond_to__input__request_4);
			}
		};
	}
}