/*
 * Copyright 2012 by A-SIT, Secure Information Technology Center Austria
 *
 * Licensed under the EUPL, Version 1.1 or - as soon they will be approved by
 * the European Commission - subsequent versions of the EUPL (the "Licence");
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at:
 * http://joinup.ec.europa.eu/software/page/eupl
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the Licence is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Licence for the specific language governing permissions and
 * limitations under the Licence.
 */
package at.asit.pdfover.gui.workflow.states;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.List;
import org.apache.pdfbox.pdmodel.PDDocument;

//Imports
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.MessageBox;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import at.asit.pdfover.gui.Constants;
import at.asit.pdfover.gui.MainWindow.Buttons;
import at.asit.pdfover.gui.MainWindowBehavior;
import at.asit.pdfover.gui.PlaceholderSelectionGui;
import at.asit.pdfover.gui.composites.DataSourceSelectComposite;
import at.asit.pdfover.gui.utils.Messages;
import at.asit.pdfover.gui.workflow.StateMachine;
import at.asit.pdfover.gui.workflow.Status;
import at.asit.pdfover.gui.workflow.config.ConfigProvider;
import at.asit.pdfover.signator.SignaturePosition;
import at.gv.egiz.pdfas.common.exceptions.PdfAsException;
import at.gv.egiz.pdfas.lib.impl.placeholder.SignaturePlaceholderData;
import at.gv.egiz.pdfas.lib.impl.pdfbox2.placeholder.SignatureFieldsExtractor;
import at.gv.egiz.pdfas.lib.impl.pdfbox2.placeholder.SignaturePlaceholderExtractor;
//import at.gv.egiz.pdfas.lib.impl.pdfbox2.placeholder.

import org.apache.commons.configuration.PropertiesConfiguration;
import org.apache.commons.configuration.PropertiesConfigurationLayout;


/**
 * Selects the data source for the signature process.
 */
public class OpenState extends State {

	/**
	 * @param stateMachine
	 */
	public OpenState(StateMachine stateMachine) {
		super(stateMachine);
	}

	/**
	 * SLF4J Logger instance
	 **/
	private static final Logger log = LoggerFactory
			.getLogger(OpenState.class);
	private static final String advancedConfig = Constants.CONFIG_DIRECTORY + File.separator + "/cfg/advancedconfig.properties"; //$NON-NLS-1$
	
	private DataSourceSelectComposite selectionComposite = null;

	private DataSourceSelectComposite getSelectionComposite() {
		if (this.selectionComposite == null) {
			this.selectionComposite =
					getStateMachine().getGUIProvider().createComposite(DataSourceSelectComposite.class, SWT.RESIZE, this);
		}
		return this.selectionComposite;
	}

	@Override
	public void run() {
		Status status = getStateMachine().getStatus();
		if (!(status.getPreviousState() instanceof PrepareConfigurationState)
				&& !(status.getPreviousState() instanceof OpenState)) {
			ConfigProvider config = getStateMachine().getConfigProvider();
			status.setBKU(config.getDefaultBKU());
			status.setDocument(null);
			status.setSignaturePosition(config.getDefaultSignaturePosition());
		}

		if (status.getDocument() == null) {
			DataSourceSelectComposite selection = this.getSelectionComposite();

			getStateMachine().getGUIProvider().display(selection);
			selection.layout();

			status.setDocument(selection.getSelected());

			if (status.getDocument() == null) {
				// Not selected yet
				return;
			}
		}
		log.debug("Got Datasource: " + getStateMachine().getStatus().getDocument().getAbsolutePath()); //$NON-NLS-1$

		// scan for signature placeholders
		// - see if we want to scan for placeholders in the settings
		if (getStateMachine().getConfigProvider().getEnablePlaceholderUsage()) {
			try {
				// - scan for placeholders
				PDDocument pddocument = PDDocument.load(getStateMachine().getStatus().getDocument());

				//first check the signature fields placeholder 
				if (getStateMachine().getConfigProvider().getUseSignatureFields()) {

					List<String> fields = SignatureFieldsExtractor.findEmptySignatureFields(pddocument);

					if (fields.size() > 0) {

						// create a dialog with ok and cancel buttons and a question
						// icon
						MessageBox dialog = new MessageBox(getStateMachine().getGUIProvider().getMainShell(),
								SWT.ICON_QUESTION | SWT.YES | SWT.NO);
						dialog.setText(Messages.getString("dataSourceSelection.usePlaceholderTitle")); //$NON-NLS-1$
						dialog.setMessage(Messages.getString("dataSourceSelection.usePlaceholderText")); //$NON-NLS-1$

						// open dialog and await user selection
						if (SWT.YES == dialog.open()) {
							
							if (fields.size() == 1) {
								addPlaceholderSelectionToConfig(fields.get(0));
								this.setNextState(new BKUSelectionState(getStateMachine()));
								return;
								
							} else if (fields.size() > 1) {

								PlaceholderSelectionGui gui = new PlaceholderSelectionGui(
										getStateMachine().getGUIProvider().getMainShell(), 65570, "text", //$NON-NLS-1$
										"select the fields", fields); //$NON-NLS-1$
								int res = gui.open();
								if (res != -1) {
									getStateMachine().getStatus().setSearchForPlaceholderSignature(true);

									addPlaceholderSelectionToConfig(fields.get(res));
									this.setNextState(new BKUSelectionState(getStateMachine()));
									return;

								}
								getStateMachine().getStatus().setSearchForPlaceholderSignature(false);
							}

						} else {
							getStateMachine().getStatus().setSearchForPlaceholderSignature(false);
						}
					}
					// second check if qr code placeholder search is enabled
				} else if (getStateMachine().getConfigProvider().getUseMarker()) {

					SignaturePlaceholderData signaturePlaceholderData = SignaturePlaceholderExtractor
							.extract(pddocument, "1", 3); //$NON-NLS-1$

					if (null != signaturePlaceholderData) {

						// create a dialog with ok and cancel buttons and a question
						// icon
						MessageBox dialog = new MessageBox(getStateMachine().getGUIProvider().getMainShell(),
								SWT.ICON_QUESTION | SWT.YES | SWT.NO);
						dialog.setText(Messages.getString("dataSourceSelection.usePlaceholderTitle")); //$NON-NLS-1$
						dialog.setMessage(Messages.getString("dataSourceSelection.usePlaceholderText")); //$NON-NLS-1$

						// open dialog and await user selection
						if (SWT.YES == dialog.open()) {

							// if the user chooses to use the signature placeholder
							// - fill the position information so that we skip to
							// the
							// next stages without breaking stuff
							SignaturePosition position = new SignaturePosition(
									signaturePlaceholderData.getTablePos().getPosX(),
									signaturePlaceholderData.getTablePos().getPosY(),
									signaturePlaceholderData.getTablePos().getPage());
							status.setSignaturePosition(position);

							getStateMachine().getStatus().setSearchForPlaceholderSignature(true);

						} else {
							getStateMachine().getStatus().setSearchForPlaceholderSignature(false);
						}
					}

				} else {
					// Do nothing
				}

			} catch (PdfAsException e) {
				// fail silently. In case we got here no dialog has been shown.
				// Just
				// proceed with the usual process.
			} catch (IOException e) {
				// fail silently. In case we got here no dialog has been shown.
				// Just
				// proceed with the usual process.
			}
		}
		
		this.setNextState(new PositioningState(getStateMachine()));
	}

	/**
	 * The selected placeholder is added to the configuration file
	 * @param selection
	 */
	@SuppressWarnings("static-method")
	private void addPlaceholderSelectionToConfig(String selection) {
		try {
			FileInputStream in = new FileInputStream(advancedConfig);
	        PropertiesConfiguration config = new PropertiesConfiguration();
	        PropertiesConfigurationLayout layout = new PropertiesConfigurationLayout(config);
	        layout.load(new InputStreamReader(new FileInputStream(advancedConfig)));

	        config.setProperty(Constants.SIGNATURE_FIELD_NAME_CONF, selection);
	        layout.save(new FileWriter(advancedConfig, false));

		} catch (Exception e) {
			log.error(e.getMessage(), e.getStackTrace());
		}

	}

	/**
	 * Open the input document selection dialog
	 */
	public void openFileDialog() {
		if (this.selectionComposite != null)
			this.selectionComposite.openFileDialog();
	}

	/* (non-Javadoc)
	 * @see at.asit.pdfover.gui.workflow.states.State#cleanUp()
	 */
	@Override
	public void cleanUp() {
		if (this.selectionComposite != null)
			this.selectionComposite.dispose();
	}

	/* (non-Javadoc)
	 * @see at.asit.pdfover.gui.workflow.states.State#setMainWindowBehavior()
	 */
	@Override
	public void updateMainWindowBehavior() {
		MainWindowBehavior behavior = getStateMachine().getStatus().getBehavior();
		behavior.reset();
		behavior.setEnabled(Buttons.CONFIG, true);
		behavior.setEnabled(Buttons.OPEN, true);
		behavior.setActive(Buttons.OPEN, true);
	}

	@Override
	public String toString()  {
		return this.getClass().getName();
	}
}