"use strict";
  /*
     Copyright (C) 2013 by Jeremy P. White <jwhite@codeweavers.com>
  
     This file is part of spice-html5.
  
     spice-html5 is free software: you can redistribute it and/or modify
     it under the terms of the GNU Lesser General Public License as published by
     the Free Software Foundation, either version 3 of the License, or
     (at your option) any later version.
  
     spice-html5 is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU Lesser General Public License for more details.
  
     You should have received a copy of the GNU Lesser General Public License
     along with spice-html5.  If not, see <http://www.gnu.org/licenses/>.
  */
  
  /*----------------------------------------------------------------------------
  **  SpiceSimulateCursor
  **      Internet Explorer 10 does not support data uri's in cursor assignment.
  **  This file provides a number of gimmicks to compensate.  First, if there
  **  is a preloaded cursor available, we will use that.  Failing that, we will
  **  simulate a cursor using an image that is moved around the screen.
  **--------------------------------------------------------------------------*/
  var SpiceSimulateCursor = {
  
  cursors : new Array(),
  unknown_cursors : new Array(),
  warned: false,
  
  add_cursor: function(sha1, value)
  {
      SpiceSimulateCursor.cursors[sha1] = value;
  },
  
  unknown_cursor: function(sha1, curdata)
  {
      if (! SpiceSimulateCursor.warned)
      {
          SpiceSimulateCursor.warned = true;
          alert("Internet Explorer does not support dynamic cursors.  " +
                "This page will now simulate cursors with images, " +
                "which will be imperfect.  We recommend using Chrome or Firefox instead.  " +
                "
  
  If you need to use Internet Explorer, you can create a static cursor " +
                "file for each cursor your application uses.  " +
                "View the console log for more information on creating static cursors for your environment.");
      }
  
      if (! SpiceSimulateCursor.unknown_cursors[sha1])
      {
          SpiceSimulateCursor.unknown_cursors[sha1] = curdata;
          console.log('Unknown cursor.  Simulation required.  To avoid simulation for this cursor, create and include a custom javascript file, and add the following line:');
          console.log('SpiceCursorSimulator.add_cursor("' + sha1 + '"), "<your filename here>.cur");');
          console.log('And then run following command, redirecting output into <your filename here>.cur:');
          console.log('php -r "echo urldecode(\'' + curdata + '\');"');
      }
  },
  
  simulate_cursor: function (spicecursor, cursor, screen, pngstr)
  {
      var cursor_sha = hex_sha1(pngstr + ' ' + cursor.header.hot_spot_x + ' ' + cursor.header.hot_spot_y);
      if (typeof SpiceSimulateCursor.cursors != 'undefined')
          if (typeof SpiceSimulateCursor.cursors[cursor_sha] != 'undefined')
          {
              var curstr = 'url(' + SpiceSimulateCursor.cursors[cursor_sha] + '), default';
              screen.style.cursor = curstr;
          }
  
      if (window.getComputedStyle(screen, null).cursor == 'auto')
      {
          SpiceSimulateCursor.unknown_cursor(cursor_sha, 
              SpiceSimulateCursor.create_icondir(cursor.header.width, cursor.header.height,
              cursor.data.byteLength, cursor.header.hot_spot_x, cursor.header.hot_spot_y) + pngstr);
  
          document.getElementById(spicecursor.parent.screen_id).style.cursor = 'none';
          if (! spicecursor.spice_simulated_cursor)
          {
              spicecursor.spice_simulated_cursor = document.createElement('img');
  
              spicecursor.spice_simulated_cursor.style.position = 'absolute';
              spicecursor.spice_simulated_cursor.style.display = 'none';
              spicecursor.spice_simulated_cursor.style.overflow = 'hidden';
  
              spicecursor.spice_simulated_cursor.spice_screen = document.getElementById(spicecursor.parent.screen_id);
  
              spicecursor.spice_simulated_cursor.addEventListener('mousemove', SpiceSimulateCursor.handle_sim_mousemove);
  
              spicecursor.spice_simulated_cursor.spice_screen.appendChild(spicecursor.spice_simulated_cursor);
          }
  
          spicecursor.spice_simulated_cursor.src = 'data:image/png,' + pngstr;
  
          spicecursor.spice_simulated_cursor.spice_hot_x = cursor.header.hot_spot_x;
          spicecursor.spice_simulated_cursor.spice_hot_y = cursor.header.hot_spot_y;
  
          spicecursor.spice_simulated_cursor.style.pointerEvents = "none";
      }
      else
      { 
          if (spicecursor.spice_simulated_cursor)
          {
              spicecursor.spice_simulated_cursor.spice_screen.removeChild(spicecursor.spice_simulated_cursor);
              delete spicecursor.spice_simulated_cursor;
          }
      }
  },
  
  handle_sim_mousemove: function(e)
  {
      var retval;
      var f = SpiceSimulateCursor.duplicate_mouse_event(e, this.spice_screen);
      return this.spice_screen.dispatchEvent(f);
  },
  
  duplicate_mouse_event: function(e, target)
  {
      var evt = document.createEvent("mouseevent");
      evt.initMouseEvent(e.type, true, true, e.view, e.detail,
          e.screenX, e.screenY, e.clientX, e.clientY,
          e.ctrlKey, e.altKey, e.shiftKey, e.metaKey, e.button, e.relatedTarget);
      return evt;
  },
  
  ICONDIR: function ()
  {
  },
  
  ICONDIRENTRY: function(width, height, bytes, hot_x, hot_y)
  {
      this.width = width;
      this.height = height;
      this.bytes = bytes;
      this.hot_x = hot_x;
      this.hot_y = hot_y;
  },
  
  
  create_icondir: function (width, height, bytes, hot_x, hot_y)
  {
      var i;
      var header = new SpiceSimulateCursor.ICONDIR();
      var entry = new SpiceSimulateCursor.ICONDIRENTRY(width, height, bytes, hot_x, hot_y);
  
      var mb = new ArrayBuffer(header.buffer_size() + entry.buffer_size());
      var at = header.to_buffer(mb);
      at = entry.to_buffer(mb, at);
  
      var u8 = new Uint8Array(mb);
      var str = "";
      for (i = 0; i < at; i++)
      {
          str += "%";
          if (u8[i] < 16)
              str += "0";
          str += u8[i].toString(16);
      }
      return str;
  },
  
  };
  
  SpiceSimulateCursor.ICONDIR.prototype = 
  {
      to_buffer: function(a, at)
      {
          at = at || 0;
          var dv = new SpiceDataView(a);
          dv.setUint16(at, 0, true); at += 2;
          dv.setUint16(at, 2, true); at += 2;
          dv.setUint16(at, 1, true); at += 2;
          return at;
      },
      buffer_size: function()
      {
          return 6;
      }
  };
  
  SpiceSimulateCursor.ICONDIRENTRY.prototype =
  {
      to_buffer: function(a, at)
      {
          at = at || 0;
          var dv = new SpiceDataView(a);
          dv.setUint8(at, this.width); at++;
          dv.setUint8(at, this.height); at++;
          dv.setUint8(at, 0); at++;  /* color palette count, unused */
          dv.setUint8(at, 0); at++;  /* reserved */
          dv.setUint16(at, this.hot_x, true); at += 2;
          dv.setUint16(at, this.hot_y, true); at += 2;
          dv.setUint32(at, this.bytes, true); at += 4;
          dv.setUint32(at, at + 4, true); at += 4;  /* Offset to bytes */
          return at;
      },
      buffer_size: function()
      {
          return 16;
      }
  };