/*
 * Copyright (c) 2013, Michael Grossmann
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * * Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * * Neither the name of the jo-widgets.org nor the
 * names of its contributors may be used to endorse or promote products
 * derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 */
package org.jowidgets.spi.impl.swt.common.widgets;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.ModifyEvent;
import org.eclipse.swt.events.ModifyListener;
import org.eclipse.swt.events.VerifyEvent;
import org.eclipse.swt.events.VerifyListener;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Text;
import org.jowidgets.common.color.IColorConstant;
import org.jowidgets.common.types.Dimension;
import org.jowidgets.common.types.Markup;
import org.jowidgets.common.verify.IInputVerifier;
import org.jowidgets.spi.impl.swt.common.color.ColorCache;
import org.jowidgets.spi.impl.swt.common.image.SwtImageRegistry;
import org.jowidgets.spi.impl.swt.common.options.SwtOptions;
import org.jowidgets.spi.impl.swt.common.util.FontProvider;
import org.jowidgets.spi.impl.verify.InputVerifierHelper;
import org.jowidgets.spi.widgets.ITextAreaSpi;
import org.jowidgets.spi.widgets.setup.ITextAreaSetupSpi;
import org.jowidgets.util.EmptyCheck;

public class TextAreaNativeScrollBarImpl extends AbstractTextInputControl implements ITextAreaSpi {

    private final Text textArea;
    private final boolean isLineWrap;

    private int lastLineCount;

    public TextAreaNativeScrollBarImpl(
        final Object parentUiReference,
        final ITextAreaSetupSpi setup,
        final SwtImageRegistry imageRegistry) {
        super(new Text((Composite) parentUiReference, getTextStyle(setup)), imageRegistry);

        lastLineCount = 0;
        isLineWrap = setup.isLineWrap();

        textArea = getUiReference();

        if (SwtOptions.hasInputVerification()) {
            final IInputVerifier inputVerifier = InputVerifierHelper.getInputVerifier(null, setup);
            if (inputVerifier != null) {
                textArea.addVerifyListener(new VerifyListener() {
                    @Override
                    public void verifyText(final VerifyEvent verifyEvent) {
                        verifyEvent.doit = inputVerifier.verify(
                                textArea.getText(),
                                verifyEvent.text,
                                verifyEvent.start,
                                verifyEvent.end);
                    }
                });
            }
        }

        if (setup.getMaxLength() != null) {
            textArea.setTextLimit(setup.getMaxLength().intValue());
        }

        registerTextControl(textArea, setup.getInputChangeEventPolicy());

        textArea.addModifyListener(new ModifyListener() {
            @Override
            public void modifyText(final ModifyEvent e) {
                checkScrollBars();
            }
        });
    }

    private void checkScrollBars() {
        if (isLineWrap && lineCountChanged()) {
            scrollToCaretPosition();
        }
    }

    private boolean lineCountChanged() {
        try {
            if (lastLineCount != textArea.getLineCount()) {
                lastLineCount = textArea.getLineCount();
                return true;
            }
        }
        catch (final NoSuchMethodError e) {
            //RWT does not support getLineCount()
            return true;
        }
        return false;
    }

    @Override
    public Text getUiReference() {
        return (Text) super.getUiReference();
    }

    @Override
    public String getText() {
        return textArea.getText();
    }

    @Override
    public void setText(final String text) {
        if (text != null) {
            textArea.setText(text);
        }
        else {
            textArea.setText("");
        }
        checkScrollBars();
        if (!getUiReference().isFocusControl()) {
            fireInputChanged(getText());
        }
    }

    @Override
    public void append(final String text) {
        if (!EmptyCheck.isEmpty(text)) {
            textArea.append(text);
            checkScrollBars();
            if (!getUiReference().isFocusControl()) {
                fireInputChanged(getText());
            }
        }
    }

    @Override
    public void setForegroundColor(final IColorConstant colorValue) {
        super.setForegroundColor(colorValue);
        textArea.setForeground(ColorCache.getInstance().getColor(colorValue));
    }

    @Override
    public void setBackgroundColor(final IColorConstant colorValue) {
        super.setBackgroundColor(colorValue);
        textArea.setBackground(ColorCache.getInstance().getColor(colorValue));
    }

    @Override
    public void setFontSize(final int size) {
        textArea.setFont(FontProvider.deriveFont(textArea.getFont(), size));
    }

    @Override
    public void setFontName(final String fontName) {
        textArea.setFont(FontProvider.deriveFont(textArea.getFont(), fontName));
    }

    @Override
    public void setMarkup(final Markup markup) {
        textArea.setFont(FontProvider.deriveFont(textArea.getFont(), markup));
    }

    @Override
    public void setSelection(final int start, final int end) {
        textArea.setSelection(start, end);
    }

    @Override
    public void select() {
        textArea.selectAll();
    }

    @Override
    public void setCaretPosition(final int pos) {
        textArea.setSelection(pos, pos);
    }

    @Override
    public int getCaretPosition() {
        return textArea.getCaretPosition();
    }

    @Override
    public void setEditable(final boolean editable) {
        textArea.setEditable(editable);
    }

    @Override
    public void setEnabled(final boolean enabled) {
        textArea.setEnabled(enabled);
    }

    @Override
    public void scrollToCaretPosition() {
        try {
            textArea.showSelection();
        }
        catch (final NoSuchMethodError e) {
            //RWT does not support showSelection()
        }
    }

    @Override
    public Dimension getMinSize() {
        return new Dimension(35, 32);
    }

    private static int getTextStyle(final ITextAreaSetupSpi setup) {
        int result = SWT.MULTI | SWT.V_SCROLL;
        if (!setup.isLineWrap()) {
            result = result | SWT.H_SCROLL;
        }
        if (setup.isLineWrap()) {
            result = result | SWT.WRAP;
        }
        if (setup.hasBorder()) {
            result = result | SWT.BORDER;
        }
        return result;
    }

}