/**
 * @license
 * Visual Blocks Editor
 *
 * Copyright 2012 Google Inc.
 * https://developers.google.com/blockly/
 *
 * 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.
 */

/**
 * @fileoverview Colour input field.
 * @author fraser@google.com (Neil Fraser)
 */
'use strict';

goog.provide('Blockly.FieldColour');

goog.require('Blockly.DropDownDiv');
goog.require('Blockly.Field');
goog.require('Blockly.utils');

goog.require('goog.style');


/**
 * Class for a colour input field.
 * @param {string} colour The initial colour in '#rrggbb' format.
 * @param {Function=} opt_validator A function that is executed when a new
 *     colour is selected.  Its sole argument is the new colour value.  Its
 *     return value becomes the selected colour, unless it is undefined, in
 *     which case the new colour stands, or it is null, in which case the change
 *     is aborted.
 * @extends {Blockly.Field}
 * @constructor
 */
Blockly.FieldColour = function(colour, opt_validator) {
  Blockly.FieldColour.superClass_.constructor.call(this, colour, opt_validator);
  this.setText(Blockly.Field.NBSP + Blockly.Field.NBSP + Blockly.Field.NBSP);
};
goog.inherits(Blockly.FieldColour, Blockly.Field);

/**
 * Construct a FieldColour from a JSON arg object.
 * @param {!Object} options A JSON object with options (colour).
 * @return {!Blockly.FieldColour} The new field instance.
 * @package
 * @nocollapse
 */
Blockly.FieldColour.fromJson = function(options) {
  return new Blockly.FieldColour(options['colour']);
};

/**
 * Default width of a colour field.
 * @type {number}
 * @private
 * @const
 */
Blockly.FieldColour.DEFAULT_WIDTH = 16;

/**
 * Default height of a colour field.
 * @type {number}
 * @private
 * @const
 */
Blockly.FieldColour.DEFAULT_HEIGHT = 12;

/**
 * Array of colours used by this field.  If null, use the global list.
 * @type {Array.<string>}
 * @private
 */
Blockly.FieldColour.prototype.colours_ = null;

/**
 * Array of colour tooltips used by this field.  If null, use the global list.
 * @type {Array.<string>}
 * @private
 */
Blockly.FieldColour.prototype.titles_ = null;

/**
 * Number of colour columns used by this field.  If 0, use the global setting.
 * By default use the global constants for columns.
 * @type {number}
 * @private
 */
Blockly.FieldColour.prototype.columns_ = 0;

/**
 * Border colour for the dropdown div showing the colour picker.  Must be a CSS
 * string.
 * @type {string}
 * @private
 */
Blockly.FieldColour.prototype.DROPDOWN_BORDER_COLOUR = 'silver';

/**
 * Background colour for the dropdown div showing the colour picker.  Must be a
 * CSS string.
 * @type {string}
 * @private
 */
Blockly.FieldColour.prototype.DROPDOWN_BACKGROUND_COLOUR = 'white';

/**
 * Install this field on a block.
 */
Blockly.FieldColour.prototype.init = function() {
  Blockly.FieldColour.superClass_.init.call(this);
  this.borderRect_.style['fillOpacity'] = 1;
  this.size_ = new goog.math.Size(Blockly.FieldColour.DEFAULT_WIDTH,
      Blockly.FieldColour.DEFAULT_HEIGHT);
  this.setValue(this.getValue());
};

/**
 * Mouse cursor style when over the hotspot that initiates the editor.
 */
Blockly.FieldColour.prototype.CURSOR = 'default';

/**
 * Close the colour picker if this input is being deleted.
 */
Blockly.FieldColour.prototype.dispose = function() {
  Blockly.WidgetDiv.hideIfOwner(this);
  Blockly.FieldColour.superClass_.dispose.call(this);
};

/**
 * Return the current colour.
 * @return {string} Current colour in '#rrggbb' format.
 */
Blockly.FieldColour.prototype.getValue = function() {
  return this.colour_;
};

/**
 * Get the size, and rerender if necessary.
 * @return {!goog.math.Size} Height and width.
 */
Blockly.FieldColour.prototype.getSize = function() {
  if (!this.size_.width) {
    this.render_();
  }

  return this.size_;
};

/**
 * Updates the width of the field.  Colour fields have a constant width, but
 * the width is sometimes reset to force a rerender.
 */
Blockly.FieldColour.prototype.updateWidth = function() {
  var width = Blockly.FieldColour.DEFAULT_WIDTH;
  if (this.borderRect_) {
    this.borderRect_.setAttribute('width',
        width + Blockly.BlockSvg.SEP_SPACE_X);
  }
  this.size_.width = width;
};

/**
 * Set the colour.
 * @param {string} colour The new colour in '#rrggbb' format.
 */
Blockly.FieldColour.prototype.setValue = function(colour) {
  if (this.sourceBlock_ && Blockly.Events.isEnabled() &&
      this.colour_ != colour) {
    Blockly.Events.fire(new Blockly.Events.BlockChange(
        this.sourceBlock_, 'field', this.name, this.colour_, colour));
  }
  this.colour_ = colour;
  if (this.borderRect_) {
    this.borderRect_.style.fill = colour;
  }
};

/**
 * Get the text from this field.  Used when the block is collapsed.
 * @return {string} Current text.
 */
Blockly.FieldColour.prototype.getText = function() {
  var colour = this.colour_;
  // Try to use #rgb format if possible, rather than #rrggbb.
  var m = colour.match(/^#(.)\1(.)\2(.)\3$/);
  if (m) {
    colour = '#' + m[1] + m[2] + m[3];
  }
  return colour;
};

/**
 * An array of colour strings for the palette.
 * Copied from goog.ui.ColorPicker.SIMPLE_GRID_COLORS
 * All colour pickers use this unless overridden with setColours.
 * @type {!Array.<string>}
 */
Blockly.FieldColour.COLOURS = [
  // grays
  '#ffffff', '#cccccc', '#c0c0c0', '#999999', '#666666', '#333333', '#000000',
  // reds
  '#ffcccc', '#ff6666', '#ff0000', '#cc0000', '#990000', '#660000', '#330000',
  // oranges
  '#ffcc99', '#ff9966', '#ff9900', '#ff6600', '#cc6600', '#993300', '#663300',
  // yellows
  '#ffff99', '#ffff66', '#ffcc66', '#ffcc33', '#cc9933', '#996633', '#663333',
  // olives
  '#ffffcc', '#ffff33', '#ffff00', '#ffcc00', '#999900', '#666600', '#333300',
  // greens
  '#99ff99', '#66ff99', '#33ff33', '#33cc00', '#009900', '#006600', '#003300',
  // turquoises
  '#99ffff', '#33ffff', '#66cccc', '#00cccc', '#339999', '#336666', '#003333',
  // blues
  '#ccffff', '#66ffff', '#33ccff', '#3366ff', '#3333ff', '#000099', '#000066',
  // purples
  '#ccccff', '#9999ff', '#6666cc', '#6633ff', '#6600cc', '#333399', '#330099',
  // violets
  '#ffccff', '#ff99ff', '#cc66cc', '#cc33cc', '#993399', '#663366', '#330033'
];

/**
 * An array of tooltip strings for the palette.  If not the same length as
 * COLOURS, the colour's hex code will be used for any missing titles.
 * All colour pickers use this unless overridden with setColours.
 * @type {!Array.<string>}
 */
Blockly.FieldColour.TITLES = [];

/**
 * Number of columns in the palette.
 * All colour pickers use this unless overridden with setColumns.
 */
Blockly.FieldColour.COLUMNS = 7;

/**
 * Set a custom colour grid for this field.
 * @param {Array.<string>} colours Array of colours for this block,
 *     or null to use default (Blockly.FieldColour.COLOURS).
 * @param {Array.<string>} opt_titles Optional array of colour tooltips,
 *     or null to use default (Blockly.FieldColour.TITLES).
 * @return {!Blockly.FieldColour} Returns itself (for method chaining).
 */
Blockly.FieldColour.prototype.setColours = function(colours, opt_titles) {
  this.colours_ = colours;
  if (opt_titles !== undefined) {
    this.titles_ = opt_titles;
  }
  return this;
};

/**
 * Set a custom grid size for this field.
 * @param {number} columns Number of columns for this block,
 *     or 0 to use default (Blockly.FieldColour.COLUMNS).
 * @return {!Blockly.FieldColour} Returns itself (for method chaining).
 */
Blockly.FieldColour.prototype.setColumns = function(columns) {
  this.columns_ = columns;
  return this;
};

/**
 * Create a palette under the colour field.
 * @private
 */
Blockly.FieldColour.prototype.showEditor_ = function() {

  Blockly.DropDownDiv.hideWithoutAnimation();
  Blockly.DropDownDiv.clearContent();

  var picker = this.createWidget_();
  Blockly.DropDownDiv.getContentDiv().appendChild(picker);
  Blockly.DropDownDiv.setColour(
      this.DROPDOWN_BACKGROUND_COLOUR, this.DROPDOWN_BORDER_COLOUR);

  Blockly.DropDownDiv.showPositionedByField(this);

  // Configure event handler on the table to listen for any event in a cell.
  Blockly.FieldColour.onUpWrapper_ = Blockly.bindEvent_(picker,
      'mouseup', this, this.onClick_);
};

/**
 * Handle a click on a colour cell.
 * @param {!Event} e Mouse event.
 * @private
 */
Blockly.FieldColour.prototype.onClick_ = function(e) {
  var cell = e.target;
  if (cell && !cell.label) {
    // The target element is the 'div', back out to the 'td'.
    cell = cell.parentNode;
  }
  var colour = cell && cell.label;
  Blockly.WidgetDiv.hide();
  if (this.sourceBlock_) {
    // Call any validation function, and allow it to override.
    colour = this.callValidator(colour);
  }
  if (colour !== null) {
    this.setValue(colour);
  }
};

/**
 * Create a colour picker widget.
 * @return {!Element} The newly created colour picker.
 * @private
 */
Blockly.FieldColour.prototype.createWidget_ = function() {
  var columns = this.columns_ || Blockly.FieldColour.COLUMNS;
  var colours = this.colours_ || Blockly.FieldColour.COLOURS;
  var titles = this.titles_ || Blockly.FieldColour.TITLES;
  var selectedColour = this.getValue();
  // Create the palette.
  var table = document.createElement('table');
  table.className = 'blocklyColourTable';
  var row;
  for (var i = 0; i < colours.length; i++) {
    if (i % columns == 0) {
      row = document.createElement('tr');
      table.appendChild(row);
    }
    var cell = document.createElement('td');
    row.appendChild(cell);
    var div = document.createElement('div');
    cell.appendChild(div);
    cell.label = colours[i];  // This becomes the value, if clicked.
    cell.title = titles[i] || colours[i];
    div.style.backgroundColor = colours[i];
    if (colours[i] == selectedColour) {
      div.className = 'blocklyColourSelected';
    }
  }
  return table;
};

/**
 * Hide the colour picker widget.
 * @private
 */
Blockly.FieldColour.widgetDispose_ = function() {
  if (Blockly.FieldColour.onUpWrapper_) {
    Blockly.unbindEvent_(Blockly.FieldColour.onUpWrapper_);
  }
  Blockly.Events.setGroup(false);
};

Blockly.Field.register('field_colour', Blockly.FieldColour);