/*

  * Copyright (c) 2008-2011, Matthias Mann

  *

  * 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 Matthias Mann 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 inventory;

 import de.matthiasmann.twl.Event;

 import de.matthiasmann.twl.ThemeInfo;

 import de.matthiasmann.twl.Widget;

 /**

  *

  * @author Matthias Mann

  */

 public class InventoryPanel extends Widget {

     private int numSlotsX;

     private int numSlotsY;

     private final ItemSlot[] slot;

     private int slotSpacing;

     private ItemSlot dragSlot;

     private ItemSlot dropSlot;

     public InventoryPanel(int numSlotsX, int numSlotsY) {

         this.numSlotsX = numSlotsX;

         this.numSlotsY = numSlotsY;

         this.slot = new ItemSlot[numSlotsX * numSlotsY];

         ItemSlot.DragListener listener = new ItemSlot.DragListener() {

             public void dragStarted(ItemSlot slot, Event evt) {

                 InventoryPanel.this.dragStarted(slot, evt);

             }

             public void dragging(ItemSlot slot, Event evt) {

                 InventoryPanel.this.dragging(slot, evt);

             }

             public void dragStopped(ItemSlot slot, Event evt) {

                 InventoryPanel.this.dragStopped(slot, evt);

             }

         };

         for(int i=0 ; i<slot.length ; i++) {

             slot[i] = new ItemSlot();

             slot[i].setListener(listener);

             add(slot[i]);

         }

         slot[0].setItem("red");

         slot[1].setItem("green");

         slot[2].setItem("blue");

         slot[3].setItem("yellow");

     }

     @Override

     public int getPreferredInnerWidth() {

         return (slot[0].getPreferredWidth() + slotSpacing)*numSlotsX - slotSpacing;

     }

     @Override

     public int getPreferredInnerHeight() {

         return (slot[0].getPreferredHeight() + slotSpacing)*numSlotsY - slotSpacing;

     }

     @Override

     protected void layout() {

         int slotWidth  = slot[0].getPreferredWidth();

         int slotHeight = slot[0].getPreferredHeight();

         for(int row=0,y=getInnerY(),i=0 ; row<numSlotsY ; row++) {

             for(int col=0,x=getInnerX() ; col<numSlotsX ; col++,i++) {

                 slot[i].adjustSize();

                 slot[i].setPosition(x, y);

                 x += slotWidth + slotSpacing;

             }

             y += slotHeight + slotSpacing;

         }

     }

     @Override

     protected void applyTheme(ThemeInfo themeInfo) {

         super.applyTheme(themeInfo);

         slotSpacing = themeInfo.getParameter("slotSpacing", 5);

     }

     void dragStarted(ItemSlot slot, Event evt) {

         if(slot.getItem() != null) {

             dragSlot = slot;

             dragging(slot, evt);

         }

     }

     void dragging(ItemSlot slot, Event evt) {

         if(dragSlot != null) {

             Widget w = getWidgetAt(evt.getMouseX(), evt.getMouseY());

             if(w instanceof ItemSlot) {

                 setDropSlot((ItemSlot)w);

             } else {

                 setDropSlot(null);

             }

         }

     }

     void dragStopped(ItemSlot slot, Event evt) {

         if(dragSlot != null) {

             dragging(slot, evt);

             if(dropSlot != null && dropSlot.canDrop() && dropSlot != dragSlot) {

                 dropSlot.setItem(dragSlot.getItem());

                 dragSlot.setItem(null);

             }

             setDropSlot(null);

             dragSlot = null;

         }

     }

     private void setDropSlot(ItemSlot slot) {

         if(slot != dropSlot) {

             if(dropSlot != null) {

                 dropSlot.setDropState(false, false);

             }

             dropSlot = slot;

             if(dropSlot != null) {

                 dropSlot.setDropState(true, dropSlot == dragSlot || dropSlot.canDrop());

             }

         }

     }

 }