/*******************************************************************************
 * Copyright (c) 2000, 2003 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

package net.sourceforge.phpdt.internal.ui.preferences;

import java.util.HashMap;
import java.util.StringTokenizer;

import net.sourceforge.phpdt.internal.ui.dialogs.StatusInfo;
import net.sourceforge.phpdt.internal.ui.dialogs.StatusUtil;
import net.sourceforge.phpdt.internal.ui.text.java.hover.JavaEditorTextHoverDescriptor;
import net.sourceforge.phpdt.internal.ui.util.PixelConverter;
import net.sourceforge.phpdt.ui.PreferenceConstants;
import net.sourceforge.phpeclipse.PHPeclipsePlugin;

import org.eclipse.core.runtime.IStatus;
import org.eclipse.jface.action.Action;
import org.eclipse.jface.dialogs.Dialog;
import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.jface.text.Assert;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.KeyEvent;
import org.eclipse.swt.events.KeyListener;
import org.eclipse.swt.events.ModifyEvent;
import org.eclipse.swt.events.ModifyListener;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.List;
import org.eclipse.swt.widgets.Text;

/**
 * Configures Java Editor hover preferences.
 * 
 * @since 2.1
 */
class JavaEditorHoverConfigurationBlock {

	private static final String DELIMITER= PreferencesMessages.getString("JavaEditorHoverConfigurationBlock.delimiter"); //$NON-NLS-1$

	// Data structure to hold the values which are edited by the user
	private static class HoverConfig {
		
		private String fModifierString;
		private boolean fIsEnabled;
		private int fStateMask;

		private HoverConfig(String modifier, int stateMask, boolean enabled) {
			fModifierString= modifier;
			fIsEnabled= enabled;
			fStateMask= stateMask;
		}
	}

	private IPreferenceStore fStore;
	private HoverConfig[] fHoverConfigs;
	private Text fModifierEditor;
	private Button fEnableField;
	private List fHoverList;
	private Text fDescription;
	private Button fShowHoverAffordanceCheckbox;
	
	private JavaEditorPreferencePage fMainPreferencePage;

	private StatusInfo fStatus;

	public JavaEditorHoverConfigurationBlock(JavaEditorPreferencePage mainPreferencePage, IPreferenceStore store) {
		Assert.isNotNull(mainPreferencePage);
		Assert.isNotNull(store);
		fMainPreferencePage= mainPreferencePage;
		fStore= store;
	}

	/**
	 * Creates page for hover preferences.
	 */
	public Control createControl(Composite parent) {

		PixelConverter pixelConverter= new PixelConverter(parent);

		Composite hoverComposite= new Composite(parent, SWT.NULL);
		GridLayout layout= new GridLayout();
		layout.numColumns= 2;
		hoverComposite.setLayout(layout);
		GridData gd= new GridData(GridData.GRAB_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL);
		hoverComposite.setLayoutData(gd);

		Label label= new Label(hoverComposite, SWT.NONE);
		label.setText(PreferencesMessages.getString("JavaEditorHoverConfigurationBlock.hoverPreferences")); //$NON-NLS-1$
		gd= new GridData(GridData.FILL_HORIZONTAL);
		gd.horizontalAlignment= GridData.BEGINNING;
		gd.horizontalSpan= 2;
		label.setLayoutData(gd);
		gd= new GridData(GridData.GRAB_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL);

		// Hover list
		fHoverList= new List(hoverComposite, SWT.SINGLE | SWT.V_SCROLL | SWT.BORDER);
		gd= new GridData(GridData.VERTICAL_ALIGN_BEGINNING | GridData.FILL_HORIZONTAL);
		int listHeight= 10 * fHoverList.getItemHeight();
		gd.heightHint= listHeight;
		fHoverList.setLayoutData(gd);
		fHoverList.addSelectionListener(new SelectionListener() {
			public void widgetSelected(SelectionEvent e) {
				handleHoverListSelection();
			}
			public void widgetDefaultSelected(SelectionEvent e) {
			}
		});


		Composite stylesComposite= new Composite(hoverComposite, SWT.NONE);
		layout= new GridLayout();
		layout.marginHeight= 0;
		layout.marginWidth= 0;
		layout.numColumns= 2;
		stylesComposite.setLayout(layout);
		gd= new GridData(GridData.FILL_HORIZONTAL);
		gd.heightHint= listHeight + (2 * fHoverList.getBorderWidth());
		stylesComposite.setLayoutData(gd);

		// Enabled checkbox		
		fEnableField= new Button(stylesComposite, SWT.CHECK);
		fEnableField.setText(PreferencesMessages.getString("JavaEditorHoverConfigurationBlock.enabled")); //$NON-NLS-1$
		gd= new GridData(GridData.FILL_HORIZONTAL);
		gd.horizontalAlignment= GridData.BEGINNING;
		gd.horizontalSpan= 2;
		fEnableField.setLayoutData(gd);
		fEnableField.addSelectionListener(new SelectionListener() {
			public void widgetSelected(SelectionEvent e) {
				int i= fHoverList.getSelectionIndex();
				boolean state= fEnableField.getSelection();
				fModifierEditor.setEnabled(state);
				fHoverConfigs[i].fIsEnabled= state;
				handleModifierModified();
			}
			public void widgetDefaultSelected(SelectionEvent e) {
			}
		});

		// Text field for modifier string
		label= new Label(stylesComposite, SWT.LEFT);
		label.setText(PreferencesMessages.getString("JavaEditorHoverConfigurationBlock.keyModifier")); //$NON-NLS-1$
		fModifierEditor= new Text(stylesComposite, SWT.BORDER);
		gd= new GridData(GridData.HORIZONTAL_ALIGN_FILL);
		fModifierEditor.setLayoutData(gd);

		fModifierEditor.addKeyListener(new KeyListener() {
			private boolean isModifierCandidate;
			public void keyPressed(KeyEvent e) {
				isModifierCandidate= e.keyCode > 0 && e.character == 0 && e.stateMask == 0;
			}
		
			public void keyReleased(KeyEvent e) {
				if (isModifierCandidate && e.stateMask > 0 && e.stateMask == e.stateMask && e.character == 0) {// && e.time -time < 1000) {
					String text= fModifierEditor.getText();
					Point selection= fModifierEditor.getSelection();
					int i= selection.x - 1;
					while (i > -1 && Character.isWhitespace(text.charAt(i))) {
						i--;
					}
					boolean needsPrefixDelimiter= i > -1 && !String.valueOf(text.charAt(i)).equals(DELIMITER);

					i= selection.y;
					while (i < text.length() && Character.isWhitespace(text.charAt(i))) {
						i++;
					}
					boolean needsPostfixDelimiter= i < text.length() && !String.valueOf(text.charAt(i)).equals(DELIMITER);

					String insertString;

					if (needsPrefixDelimiter && needsPostfixDelimiter)
						insertString= PreferencesMessages.getFormattedString("JavaEditorHoverConfigurationBlock.insertDelimiterAndModifierAndDelimiter", new String[] {Action.findModifierString(e.stateMask)}); //$NON-NLS-1$
					else if (needsPrefixDelimiter)
						insertString= PreferencesMessages.getFormattedString("JavaEditorHoverConfigurationBlock.insertDelimiterAndModifier", new String[] {Action.findModifierString(e.stateMask)}); //$NON-NLS-1$
					else if (needsPostfixDelimiter)
						insertString= PreferencesMessages.getFormattedString("JavaEditorHoverConfigurationBlock.insertModifierAndDelimiter", new String[] {Action.findModifierString(e.stateMask)}); //$NON-NLS-1$
					else
						insertString= Action.findModifierString(e.stateMask);

					if (insertString != null)
						fModifierEditor.insert(insertString);
				}
			}
		});

		fModifierEditor.addModifyListener(new ModifyListener() {
			public void modifyText(ModifyEvent e) {
				handleModifierModified();
			}
		});

		// Description
		Label descriptionLabel= new Label(stylesComposite, SWT.LEFT);
		descriptionLabel.setText(PreferencesMessages.getString("JavaEditorHoverConfigurationBlock.description")); //$NON-NLS-1$
		gd= new GridData(GridData.VERTICAL_ALIGN_BEGINNING);
		gd.horizontalSpan= 2;
		descriptionLabel.setLayoutData(gd);
		fDescription= new Text(stylesComposite, SWT.LEFT | SWT.WRAP | SWT.MULTI | SWT.READ_ONLY | SWT.BORDER);
		gd= new GridData(GridData.FILL_BOTH);
		gd.horizontalSpan= 2;
		fDescription.setLayoutData(gd);

		// Vertical filler
		Label filler= new Label(hoverComposite, SWT.LEFT);
		gd= new GridData(GridData.BEGINNING | GridData.VERTICAL_ALIGN_FILL);
		gd.heightHint= pixelConverter.convertHeightInCharsToPixels(1) / 3;
		filler.setLayoutData(gd);

		// Affordance checkbox
		fShowHoverAffordanceCheckbox= new Button(hoverComposite, SWT.CHECK);
		fShowHoverAffordanceCheckbox.setText(PreferencesMessages.getString("JavaEditorHoverConfigurationBlock.showAffordance")); //$NON-NLS-1$
		gd= new GridData(GridData.HORIZONTAL_ALIGN_BEGINNING);
		gd.horizontalIndent= 0;
		gd.horizontalSpan= 2;
		fShowHoverAffordanceCheckbox.setLayoutData(gd);

		initialize();

		Dialog.applyDialogFont(hoverComposite);
		return hoverComposite;
	}

	private JavaEditorTextHoverDescriptor[] getContributedHovers() {
		return PHPeclipsePlugin.getDefault().getJavaEditorTextHoverDescriptors();		
	}

	void initialize() {
		JavaEditorTextHoverDescriptor[] hoverDescs= getContributedHovers();
		fHoverConfigs= new HoverConfig[hoverDescs.length];
		for (int i= 0; i < hoverDescs.length; i++) {
			fHoverConfigs[i]= new HoverConfig(hoverDescs[i].getModifierString(), hoverDescs[i].getStateMask(), hoverDescs[i].isEnabled());
			fHoverList.add(hoverDescs[i].getLabel());
		}
		initializeFields();
	}

	void initializeFields() {
		fHoverList.getDisplay().asyncExec(new Runnable() {
			public void run() {
				if (fHoverList != null && !fHoverList.isDisposed()) {
					fHoverList.select(0);
					handleHoverListSelection();
				}
			}
		});
		fShowHoverAffordanceCheckbox.setSelection(fStore.getBoolean(PreferenceConstants.EDITOR_SHOW_TEXT_HOVER_AFFORDANCE));
	}

	void performOk() {
		StringBuffer buf= new StringBuffer();
		StringBuffer maskBuf= new StringBuffer();
		for (int i= 0; i < fHoverConfigs.length; i++) {
			buf.append(getContributedHovers()[i].getId());
			buf.append(JavaEditorTextHoverDescriptor.VALUE_SEPARATOR);
			if (!fHoverConfigs[i].fIsEnabled)
				buf.append(JavaEditorTextHoverDescriptor.DISABLED_TAG);
			String modifier= fHoverConfigs[i].fModifierString;
			if (modifier == null || modifier.length() == 0)
				modifier= JavaEditorTextHoverDescriptor.NO_MODIFIER;
			buf.append(modifier);
			buf.append(JavaEditorTextHoverDescriptor.VALUE_SEPARATOR);
			
			maskBuf.append(getContributedHovers()[i].getId());
			maskBuf.append(JavaEditorTextHoverDescriptor.VALUE_SEPARATOR);
			maskBuf.append(fHoverConfigs[i].fStateMask);
			maskBuf.append(JavaEditorTextHoverDescriptor.VALUE_SEPARATOR);
		}
		fStore.setValue(PreferenceConstants.EDITOR_TEXT_HOVER_MODIFIERS, buf.toString());
		fStore.setValue(PreferenceConstants.EDITOR_TEXT_HOVER_MODIFIER_MASKS, maskBuf.toString());
		
		fStore.setValue(PreferenceConstants.EDITOR_SHOW_TEXT_HOVER_AFFORDANCE, fShowHoverAffordanceCheckbox.getSelection());
		
		PHPeclipsePlugin.getDefault().resetJavaEditorTextHoverDescriptors();
	}

	void performDefaults() {
		restoreFromPreferences();
		initializeFields();
	}

	private void restoreFromPreferences() {

		fShowHoverAffordanceCheckbox.setSelection(fStore.getBoolean(PreferenceConstants.EDITOR_SHOW_TEXT_HOVER_AFFORDANCE));

		String compiledTextHoverModifiers= fStore.getString(PreferenceConstants.EDITOR_TEXT_HOVER_MODIFIERS);
		
		StringTokenizer tokenizer= new StringTokenizer(compiledTextHoverModifiers, JavaEditorTextHoverDescriptor.VALUE_SEPARATOR);
		HashMap idToModifier= new HashMap(tokenizer.countTokens() / 2);

		while (tokenizer.hasMoreTokens()) {
			String id= tokenizer.nextToken();
			if (tokenizer.hasMoreTokens())
				idToModifier.put(id, tokenizer.nextToken());
		}

		String compiledTextHoverModifierMasks= PHPeclipsePlugin.getDefault().getPreferenceStore().getString(PreferenceConstants.EDITOR_TEXT_HOVER_MODIFIER_MASKS);

		tokenizer= new StringTokenizer(compiledTextHoverModifierMasks, JavaEditorTextHoverDescriptor.VALUE_SEPARATOR);
		HashMap idToModifierMask= new HashMap(tokenizer.countTokens() / 2);

		while (tokenizer.hasMoreTokens()) {
			String id= tokenizer.nextToken();
			if (tokenizer.hasMoreTokens())
				idToModifierMask.put(id, tokenizer.nextToken());
		}

		for (int i= 0; i < fHoverConfigs.length; i++) {
			String modifierString= (String)idToModifier.get(getContributedHovers()[i].getId());
			boolean enabled= true;
			if (modifierString == null)
				modifierString= JavaEditorTextHoverDescriptor.DISABLED_TAG;
			
			if (modifierString.startsWith(JavaEditorTextHoverDescriptor.DISABLED_TAG)) {
				enabled= false;
				modifierString= modifierString.substring(1);
			}

			if (modifierString.equals(JavaEditorTextHoverDescriptor.NO_MODIFIER))
				modifierString= ""; //$NON-NLS-1$

			fHoverConfigs[i].fModifierString= modifierString;
			fHoverConfigs[i].fIsEnabled= enabled;
			fHoverConfigs[i].fStateMask= JavaEditorTextHoverDescriptor.computeStateMask(modifierString);

			if (fHoverConfigs[i].fStateMask == -1) {
				try {
					fHoverConfigs[i].fStateMask= Integer.parseInt((String)idToModifierMask.get(getContributedHovers()[i].getId()));
				} catch (NumberFormatException ex) {
					fHoverConfigs[i].fStateMask= -1;
				}
			}
		}
	}

	private void handleModifierModified() {
		int i= fHoverList.getSelectionIndex();
		String modifiers= fModifierEditor.getText();
		fHoverConfigs[i].fModifierString= modifiers;
		fHoverConfigs[i].fStateMask= JavaEditorTextHoverDescriptor.computeStateMask(modifiers);
		if (fHoverConfigs[i].fIsEnabled && fHoverConfigs[i].fStateMask == -1)
			fStatus= new StatusInfo(IStatus.ERROR, PreferencesMessages.getFormattedString("JavaEditorHoverConfigurationBlock.modifierIsNotValid", fHoverConfigs[i].fModifierString)); //$NON-NLS-1$
		else
			fStatus= new StatusInfo();
		updateStatus();
	}

	private void handleHoverListSelection() {	
		int i= fHoverList.getSelectionIndex();
		boolean enabled= fHoverConfigs[i].fIsEnabled;
		fEnableField.setSelection(enabled);
		fModifierEditor.setEnabled(enabled);
		fModifierEditor.setText(fHoverConfigs[i].fModifierString);
		String description= getContributedHovers()[i].getDescription();
		if (description == null)
			description= ""; //$NON-NLS-1$
		fDescription.setText(description);
	}

	IStatus getStatus() {
		if (fStatus == null)
			fStatus= new StatusInfo();
		return fStatus;
	}

	private void updateStatus() {
		int i= 0;
		HashMap stateMasks= new HashMap(fHoverConfigs.length);
		while (fStatus.isOK() && i < fHoverConfigs.length) {
			if (fHoverConfigs[i].fIsEnabled) {
				String label= getContributedHovers()[i].getLabel();
				Integer stateMask= new Integer(fHoverConfigs[i].fStateMask);
				if (fHoverConfigs[i].fStateMask == -1)
					fStatus= new StatusInfo(IStatus.ERROR, PreferencesMessages.getFormattedString("JavaEditorHoverConfigurationBlock.modifierIsNotValidForHover", new String[] {fHoverConfigs[i].fModifierString, label})); //$NON-NLS-1$
				else if (stateMasks.containsKey(stateMask))
					fStatus= new StatusInfo(IStatus.ERROR, PreferencesMessages.getFormattedString("JavaEditorHoverConfigurationBlock.duplicateModifier", new String[] {label, (String)stateMasks.get(stateMask)})); //$NON-NLS-1$
				else
					stateMasks.put(stateMask, label);
			}
			i++;
		}

		if (fStatus.isOK())
			fMainPreferencePage.updateStatus(fStatus);
		else {
			fMainPreferencePage.setValid(false);
			StatusUtil.applyToStatusLine(fMainPreferencePage, fStatus);
		}
	}
}