/*
 * Ext GWT - Ext for GWT
 * Copyright(c) 2007-2009, Ext JS, LLC.
 * licensing@extjs.com
 * 
 * http://extjs.com/license
 */
package com.extjs.gxt.ui.client.widget.tips;

import com.extjs.gxt.ui.client.event.ComponentEvent;
import com.extjs.gxt.ui.client.event.EventType;
import com.extjs.gxt.ui.client.event.Events;
import com.extjs.gxt.ui.client.event.Listener;
import com.extjs.gxt.ui.client.util.Util;
import com.extjs.gxt.ui.client.widget.Component;
import com.google.gwt.user.client.Element;

/**
 * A specialized tooltip class for tooltips that can be specified in markup.
 * 
 * <p />
 * Quicktips can be configured via tag attributes directly in markup. Below is
 * the summary of the configuration properties which can be used.
 * 
 * <ul>
 * <li>text (required)</li>
 * <li>title</li>
 * <li>width</li>
 * </ul>
 * 
 * <p />
 * To register a quick tip in markup, you simply add one or more of the valid
 * QuickTip attributes prefixed with the <b>ext:</b> namespace. The HTML element
 * itself is automatically set as the quick tip target. Here is the summary of
 * supported attributes (optional unless otherwise noted):
 * 
 * <ul>
 * <li><b>qtip (required)</b>: The quick tip text (equivalent to the 'text'
 * target element config).</li>
 * <li><b>qtitle</b>: The quick tip title (equivalent to the 'title' target
 * element config).</li>
 * <li><b>qwidth</b>: The quick tip width (equivalent to the 'width' target
 * element config).</li>
 * </ul>
 */
public class QuickTip extends ToolTip {

  private boolean initialized;
  private boolean interceptTitles;
  private Element targetElem;

  /**
   * Creates a new quick tip instance.
   * 
   * @param component the source component
   */
  public QuickTip(Component component) {
    super(component);
  }

  /**
   * Returns true if intercept titles is enabled.
   * 
   * @return the intercept title state
   */
  public boolean isInterceptTitles() {
    return interceptTitles;
  }

  /**
   * True to automatically use the element's DOM title value if available
   * (defaults to false).
   * 
   * @param intercepTitiles true to to intercept titles
   */
  public void setInterceptTitles(boolean intercepTitiles) {
    this.interceptTitles = intercepTitiles;
  }

  @Override
  public void initTarget(Component target) {
    if (listener == null) {
      listener = new Listener<ComponentEvent>() {
        public void handleEvent(ComponentEvent be) {
          EventType type = be.getType();
          if (type == Events.OnMouseOver) {
            onTargetOver(be);
          } else if (type == Events.OnMouseOut) {
            onTargetOut(be);
          } else if (type == Events.OnMouseMove) {
            onMouseMove(be);
          } else if (type == Events.Hide || type == Events.Detach) {
            hide();
          }
        }
      };
    }
    super.initTarget(target);
  }

  @Override
  protected void onTargetOut(ComponentEvent ce) {
    if (targetElem == null) {
      super.onTargetOut(ce);
    }
  }

  @Override
  protected void onTargetOver(ComponentEvent ce) {
    if (disabled) {
      return;
    }

    Element t = ce.getTarget();
    while (t != null && t != target.getElement()) {
      if (hasTip(t)) {
        break;
      }
      t = (Element) t.getParentElement();
    }

    boolean hasTip = t != null && hasTip(t);

    if (!initialized && !hasTip) {
      return;
    }
    initialized = true;

    if (targetElem == null && hasTip) {
      updateTargetElement(t);
    } else {
      if (hasTip && targetElem != t) {
        updateTargetElement(t);
      } else if (targetElem != null && ce.within(targetElem)) {
        return;
      } else {
        clearTimers();
        hide();
        targetElem = null;
        text = null;
        title = null;
        return;
      }
    }

    clearTimer("hide");
    targetXY = ce.getXY();
    delayShow();
  }

  private String getAttributeValue(Element target, String attr) {
    String v = target.getAttribute(attr);
    return hasAttributeValue(v) ? v : null;
  }

  private boolean hasAttributeValue(String v) {
    return v != null && !v.equals("");
  }

  private boolean hasTip(Element target) {
    String tip = target.getAttribute("qtip");
    String title = target.getAttribute("title");
    return hasAttributeValue(tip) || (interceptTitles && hasAttributeValue(title));
  }

  private void updateTargetElement(Element target) {
    targetElem = target;
    text = interceptTitles ? getAttributeValue(target, "title") : getAttributeValue(
        target, "qtip");
    title = getAttributeValue(target, "qtitle");

    String width = getAttributeValue(target, "qwidth");
    if (width != null) {
      setWidth(Util.parseInt(width, 100));
    }
  }

}