/*
 * Copyright 2011 Vaadin Ltd.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.vaadin.terminal.gwt.client.ui;

import com.google.gwt.dom.client.InputElement;
import com.google.gwt.dom.client.LabelElement;
import com.google.gwt.dom.client.Node;
import com.google.gwt.dom.client.NodeList;
import com.google.gwt.event.dom.client.BlurEvent;
import com.google.gwt.event.dom.client.BlurHandler;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.dom.client.FocusEvent;
import com.google.gwt.event.dom.client.FocusHandler;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.user.client.DOM;
import com.google.gwt.user.client.Element;
import com.google.gwt.user.client.Event;
import com.vaadin.terminal.gwt.client.ApplicationConnection;
import com.vaadin.terminal.gwt.client.BrowserInfo;
import com.vaadin.terminal.gwt.client.EventHelper;
import com.vaadin.terminal.gwt.client.EventId;
import com.vaadin.terminal.gwt.client.MouseEventDetails;
import com.vaadin.terminal.gwt.client.Paintable;
import com.vaadin.terminal.gwt.client.UIDL;
import com.vaadin.terminal.gwt.client.Util;
import com.vaadin.terminal.gwt.client.VTooltip;

public class VCheckBox extends com.google.gwt.user.client.ui.CheckBox implements
        Paintable, Field, FocusHandler, BlurHandler {

    public static final String CLASSNAME = "v-checkbox";

    String id;

    boolean immediate;

    ApplicationConnection client;

    private Element errorIndicatorElement;

    private Icon icon;

    private HandlerRegistration focusHandlerRegistration;
    private HandlerRegistration blurHandlerRegistration;

    public VCheckBox() {
        setStyleName(CLASSNAME);
        addClickHandler(new ClickHandler() {

            public void onClick(ClickEvent event) {
                if (id == null || client == null || !isEnabled()) {
                    return;
                }
                if (BrowserInfo.get().isWebkit()) {
                    // Webkit does not focus non-text input elements on click
                    // (#11854)
                    setFocus(true);
                }

                // Add mouse details
                MouseEventDetails details = new MouseEventDetails(
                        event.getNativeEvent(), getElement());
                client.updateVariable(id, "mousedetails", details.serialize(),
                        false);
                client.updateVariable(id, "state", getValue(), immediate);
            }

        });
        sinkEvents(VTooltip.TOOLTIP_EVENTS);
        Element el = DOM.getFirstChild(getElement());
        while (el != null) {
            DOM.sinkEvents(el,
                    (DOM.getEventsSunk(el) | VTooltip.TOOLTIP_EVENTS));
            el = DOM.getNextSibling(el);
        }
    }

    public void updateFromUIDL(UIDL uidl, ApplicationConnection client) {
        // Save details
        this.client = client;
        id = uidl.getId();

        // Ensure correct implementation
        if (client.updateComponent(this, uidl, false)) {
            return;
        }

        focusHandlerRegistration = EventHelper.updateFocusHandler(this, client,
                focusHandlerRegistration);
        blurHandlerRegistration = EventHelper.updateBlurHandler(this, client,
                blurHandlerRegistration);

        if (uidl.hasAttribute("error")) {
            if (errorIndicatorElement == null) {
                errorIndicatorElement = DOM.createSpan();
                errorIndicatorElement.setInnerHTML(" ");
                DOM.setElementProperty(errorIndicatorElement, "className",
                        "v-errorindicator");
                DOM.appendChild(getElement(), errorIndicatorElement);
                DOM.sinkEvents(errorIndicatorElement, VTooltip.TOOLTIP_EVENTS
                        | Event.ONCLICK);
            } else {
                DOM.setStyleAttribute(errorIndicatorElement, "display", "");
            }
        } else if (errorIndicatorElement != null) {
            DOM.setStyleAttribute(errorIndicatorElement, "display", "none");
        }

        if (uidl.hasAttribute("readonly")) {
            setEnabled(false);
        }

        if (uidl.hasAttribute("icon")) {
            if (icon == null) {
                icon = new Icon(client);
                DOM.insertChild(getElement(), icon.getElement(), 1);
                icon.sinkEvents(VTooltip.TOOLTIP_EVENTS);
                icon.sinkEvents(Event.ONCLICK);
            }
            icon.setUri(uidl.getStringAttribute("icon"));
        } else if (icon != null) {
            // detach icon
            DOM.removeChild(getElement(), icon.getElement());
            icon = null;
        }

        // Set text
        setText(uidl.getStringAttribute("caption"));
        setValue(uidl.getBooleanVariable("state"));
        immediate = uidl.getBooleanAttribute("immediate");
    }

    @Override
    public void setText(String text) {
        super.setText(text);
        if (BrowserInfo.get().isIE() && BrowserInfo.get().getIEVersion() < 8) {

            boolean breakLink = text == null || "".equals(text);

            // break or create link between label element and checkbox, to
            // enable native focus outline around checkbox element itself, if
            // caption is not present
            NodeList<Node> childNodes = getElement().getChildNodes();
            String id = null;
            for (int i = 0; i < childNodes.getLength(); i++) {
                Node item = childNodes.getItem(i);
                if (item.getNodeName().toLowerCase().equals("input")) {
                    InputElement input = (InputElement) item;
                    id = input.getId();
                }
                if (item.getNodeName().toLowerCase().equals("label")) {
                    LabelElement label = (LabelElement) item;
                    if (breakLink) {
                        label.setHtmlFor("");
                    } else {
                        label.setHtmlFor(id);
                    }
                }
            }
        }
    }

    @Override
    public void onBrowserEvent(Event event) {
        if (icon != null && (event.getTypeInt() == Event.ONCLICK)
                && (DOM.eventGetTarget(event) == icon.getElement())) {
            // Click on icon should do nothing if widget is disabled
            if (isEnabled()) {
                setValue(!getValue());
            }
        }
        super.onBrowserEvent(event);
        if (event.getTypeInt() == Event.ONLOAD) {
            Util.notifyParentOfSizeChange(this, true);
        }
        if (client != null) {
            client.handleTooltipEvent(event, this);
        }
    }

    @Override
    public void setWidth(String width) {
        super.setWidth(width);
    }

    @Override
    public void setHeight(String height) {
        super.setHeight(height);
    }

    public void onFocus(FocusEvent arg0) {
        client.updateVariable(id, EventId.FOCUS, "", true);
    }

    public void onBlur(BlurEvent arg0) {
        client.updateVariable(id, EventId.BLUR, "", true);
    }
}