blockly/blocks/text.js

/**
 * @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 Text blocks for Blockly.
 * @author fraser@google.com (Neil Fraser)
 */
'use strict';

goog.provide('Blockly.Blocks.texts');  // Deprecated
goog.provide('Blockly.Constants.Text');

goog.require('Blockly.Blocks');
goog.require('Blockly');


/**
 * Common HSV hue for all blocks in this category.
 * Should be the same as Blockly.Msg.TEXTS_HUE
 * @readonly
 */
Blockly.Constants.Text.HUE = 160;
/** @deprecated Use Blockly.Constants.Text.HUE */
Blockly.Blocks.texts.HUE = Blockly.Constants.Text.HUE;

Blockly.defineBlocksWithJsonArray([  // BEGIN JSON EXTRACT
  // Block for text value
  {
    "type": "text",
    "message0": "%1",
    "args0": [{
      "type": "field_input",
      "name": "TEXT",
      "text": ""
    }],
    "output": "String",
    "colour": "%{BKY_TEXTS_HUE}",
    "helpUrl": "%{BKY_TEXT_TEXT_HELPURL}",
    "tooltip": "%{BKY_TEXT_TEXT_TOOLTIP}",
    "extensions": [
      "text_quotes",
      "parent_tooltip_when_inline"
    ]
  },
  {
    "type": "text_join",
    "message0": "",
    "output": "String",
    "colour": "%{BKY_TEXTS_HUE}",
    "helpUrl": "%{BKY_TEXT_JOIN_HELPURL}",
    "tooltip": "%{BKY_TEXT_JOIN_TOOLTIP}",
    "mutator": "text_join_mutator"

  },
  {
    "type": "text_create_join_container",
    "message0": "%{BKY_TEXT_CREATE_JOIN_TITLE_JOIN} %1 %2",
    "args0": [{
      "type": "input_dummy"
    },
    {
      "type": "input_statement",
      "name": "STACK"
    }],
    "colour": "%{BKY_TEXTS_HUE}",
    "tooltip": "%{BKY_TEXT_CREATE_JOIN_TOOLTIP}",
    "enableContextMenu": false
  },
  {
    "type": "text_create_join_item",
    "message0": "%{BKY_TEXT_CREATE_JOIN_ITEM_TITLE_ITEM}",
    "previousStatement": null,
    "nextStatement": null,
    "colour": "%{BKY_TEXTS_HUE}",
    "tooltip": "{%BKY_TEXT_CREATE_JOIN_ITEM_TOOLTIP}",
    "enableContextMenu": false
  },
  {
    "type": "text_append",
    "message0": "%{BKY_TEXT_APPEND_TITLE}",
    "args0": [{
      "type": "field_variable",
      "name": "VAR",
      "variable": "%{BKY_TEXT_APPEND_VARIABLE}"
    },
    {
      "type": "input_value",
      "name": "TEXT"
    }],
    "previousStatement": null,
    "nextStatement": null,
    "colour": "%{BKY_TEXTS_HUE}",
    "extensions": [
      "text_append_tooltip"
    ]
  },
  {
    "type": "text_length",
    "message0": "%{BKY_TEXT_LENGTH_TITLE}",
    "args0": [
      {
        "type": "input_value",
        "name": "VALUE",
        "check": ['String', 'Array']
      }
    ],
    "output": 'Number',
    "colour": "%{BKY_TEXTS_HUE}",
    "tooltip": "%{BKY_TEXT_LENGTH_TOOLTIP}",
    "helpUrl": "%{BKY_TEXT_LENGTH_HELPURL}"
  },
  {
    "type": "text_isEmpty",
    "message0": "%{BKY_TEXT_ISEMPTY_TITLE}",
    "args0": [
      {
        "type": "input_value",
        "name": "VALUE",
        "check": ['String', 'Array']
      }
    ],
    "output": 'Boolean',
    "colour": "%{BKY_TEXTS_HUE}",
    "tooltip": "%{BKY_TEXT_ISEMPTY_TOOLTIP}",
    "helpUrl": "%{BKY_TEXT_ISEMPTY_HELPURL}"
  },
  {
    "type": "text_indexOf",
    "message0": "%{BKY_TEXT_INDEXOF_TITLE}",
    "args0": [
      {
        "type": "input_value",
        "name": "VALUE",
        "check": "String"
      },
      {
        "type": "field_dropdown",
        "name": "END",
        "options": [
          [
            "%{BKY_TEXT_INDEXOF_OPERATOR_FIRST}",
            "FIRST"
          ],
          [
            "%{BKY_TEXT_INDEXOF_OPERATOR_LAST}",
            "LAST"
          ]
        ]
      },
      {
        "type": "input_value",
        "name": "FIND",
        "check": "String"
      }
    ],
    "output": "Number",
    "colour": "%{BKY_TEXTS_HUE}",
    "helpUrl": "%{BKY_TEXT_INDEXOF_HELPURL}",
    "inputsInline": true,
    "extensions": [
      "text_indexOf_tooltip"
    ]
  },
  {
    "type": "text_charAt",
    "message0": "%{BKY_TEXT_CHARAT_TITLE}", // "in text %1 %2"
    "args0": [
      {
        "type":"input_value",
        "name": "VALUE",
        "check": "String"
      },
      {
        "type": "input_dummy",
        "name": "AT"
      }
    ],
    "output": "String",
    "colour": "%{BKY_TEXTS_HUE}",
    "helpUrl": "%{BKY_TEXT_CHARAT_HELPURL}",
    "inputsInline": true,
    "mutator": "text_charAt_mutator"
  }
]);  // END JSON EXTRACT (Do not delete this comment.)

Blockly.Blocks['text_getSubstring'] = {
  /**
   * Block for getting substring.
   * @this Blockly.Block
   */
  init: function() {
    this['WHERE_OPTIONS_1'] = [
      [Blockly.Msg.TEXT_GET_SUBSTRING_START_FROM_START, 'FROM_START'],
      [Blockly.Msg.TEXT_GET_SUBSTRING_START_FROM_END, 'FROM_END'],
      [Blockly.Msg.TEXT_GET_SUBSTRING_START_FIRST, 'FIRST']
    ];
    this['WHERE_OPTIONS_2'] = [
      [Blockly.Msg.TEXT_GET_SUBSTRING_END_FROM_START, 'FROM_START'],
      [Blockly.Msg.TEXT_GET_SUBSTRING_END_FROM_END, 'FROM_END'],
      [Blockly.Msg.TEXT_GET_SUBSTRING_END_LAST, 'LAST']
    ];
    this.setHelpUrl(Blockly.Msg.TEXT_GET_SUBSTRING_HELPURL);
    this.setColour(Blockly.Blocks.texts.HUE);
    this.appendValueInput('STRING')
        .setCheck('String')
        .appendField(Blockly.Msg.TEXT_GET_SUBSTRING_INPUT_IN_TEXT);
    this.appendDummyInput('AT1');
    this.appendDummyInput('AT2');
    if (Blockly.Msg.TEXT_GET_SUBSTRING_TAIL) {
      this.appendDummyInput('TAIL')
          .appendField(Blockly.Msg.TEXT_GET_SUBSTRING_TAIL);
    }
    this.setInputsInline(true);
    this.setOutput(true, 'String');
    this.updateAt_(1, true);
    this.updateAt_(2, true);
    this.setTooltip(Blockly.Msg.TEXT_GET_SUBSTRING_TOOLTIP);
  },
  /**
   * Create XML to represent whether there are 'AT' inputs.
   * @return {!Element} XML storage element.
   * @this Blockly.Block
   */
  mutationToDom: function() {
    var container = document.createElement('mutation');
    var isAt1 = this.getInput('AT1').type == Blockly.INPUT_VALUE;
    container.setAttribute('at1', isAt1);
    var isAt2 = this.getInput('AT2').type == Blockly.INPUT_VALUE;
    container.setAttribute('at2', isAt2);
    return container;
  },
  /**
   * Parse XML to restore the 'AT' inputs.
   * @param {!Element} xmlElement XML storage element.
   * @this Blockly.Block
   */
  domToMutation: function(xmlElement) {
    var isAt1 = (xmlElement.getAttribute('at1') == 'true');
    var isAt2 = (xmlElement.getAttribute('at2') == 'true');
    this.updateAt_(1, isAt1);
    this.updateAt_(2, isAt2);
  },
  /**
   * Create or delete an input for a numeric index.
   * This block has two such inputs, independant of each other.
   * @param {number} n Specify first or second input (1 or 2).
   * @param {boolean} isAt True if the input should exist.
   * @private
   * @this Blockly.Block
   */
  updateAt_: function(n, isAt) {
    // Create or delete an input for the numeric index.
    // Destroy old 'AT' and 'ORDINAL' inputs.
    this.removeInput('AT' + n);
    this.removeInput('ORDINAL' + n, true);
    // Create either a value 'AT' input or a dummy input.
    if (isAt) {
      this.appendValueInput('AT' + n).setCheck('Number');
      if (Blockly.Msg.ORDINAL_NUMBER_SUFFIX) {
        this.appendDummyInput('ORDINAL' + n)
            .appendField(Blockly.Msg.ORDINAL_NUMBER_SUFFIX);
      }
    } else {
      this.appendDummyInput('AT' + n);
    }
    // Move tail, if present, to end of block.
    if (n == 2 && Blockly.Msg.TEXT_GET_SUBSTRING_TAIL) {
      this.removeInput('TAIL', true);
      this.appendDummyInput('TAIL')
          .appendField(Blockly.Msg.TEXT_GET_SUBSTRING_TAIL);
    }
    var menu = new Blockly.FieldDropdown(this['WHERE_OPTIONS_' + n],
        function(value) {
          var newAt = (value == 'FROM_START') || (value == 'FROM_END');
          // The 'isAt' variable is available due to this function being a
          // closure.
          if (newAt != isAt) {
            var block = this.sourceBlock_;
            block.updateAt_(n, newAt);
            // This menu has been destroyed and replaced.
            // Update the replacement.
            block.setFieldValue(value, 'WHERE' + n);
            return null;
          }
          return undefined;
        });

    this.getInput('AT' + n)
        .appendField(menu, 'WHERE' + n);
    if (n == 1) {
      this.moveInputBefore('AT1', 'AT2');
    }
  }
};

Blockly.Blocks['text_changeCase'] = {
  /**
   * Block for changing capitalization.
   * @this Blockly.Block
   */
  init: function() {
    var OPERATORS = [
      [Blockly.Msg.TEXT_CHANGECASE_OPERATOR_UPPERCASE, 'UPPERCASE'],
      [Blockly.Msg.TEXT_CHANGECASE_OPERATOR_LOWERCASE, 'LOWERCASE'],
      [Blockly.Msg.TEXT_CHANGECASE_OPERATOR_TITLECASE, 'TITLECASE']
    ];
    this.setHelpUrl(Blockly.Msg.TEXT_CHANGECASE_HELPURL);
    this.setColour(Blockly.Blocks.texts.HUE);
    this.appendValueInput('TEXT')
        .setCheck('String')
        .appendField(new Blockly.FieldDropdown(OPERATORS), 'CASE');
    this.setOutput(true, 'String');
    this.setTooltip(Blockly.Msg.TEXT_CHANGECASE_TOOLTIP);
  }
};

Blockly.Blocks['text_trim'] = {
  /**
   * Block for trimming spaces.
   * @this Blockly.Block
   */
  init: function() {
    var OPERATORS = [
      [Blockly.Msg.TEXT_TRIM_OPERATOR_BOTH, 'BOTH'],
      [Blockly.Msg.TEXT_TRIM_OPERATOR_LEFT, 'LEFT'],
      [Blockly.Msg.TEXT_TRIM_OPERATOR_RIGHT, 'RIGHT']
    ];
    this.setHelpUrl(Blockly.Msg.TEXT_TRIM_HELPURL);
    this.setColour(Blockly.Blocks.texts.HUE);
    this.appendValueInput('TEXT')
        .setCheck('String')
        .appendField(new Blockly.FieldDropdown(OPERATORS), 'MODE');
    this.setOutput(true, 'String');
    this.setTooltip(Blockly.Msg.TEXT_TRIM_TOOLTIP);
  }
};

Blockly.Blocks['text_print'] = {
  /**
   * Block for print statement.
   * @this Blockly.Block
   */
  init: function() {
    this.jsonInit({
      "message0": Blockly.Msg.TEXT_PRINT_TITLE,
      "args0": [
        {
          "type": "input_value",
          "name": "TEXT"
        }
      ],
      "previousStatement": null,
      "nextStatement": null,
      "colour": Blockly.Blocks.texts.HUE,
      "tooltip": Blockly.Msg.TEXT_PRINT_TOOLTIP,
      "helpUrl": Blockly.Msg.TEXT_PRINT_HELPURL
    });
  }
};

Blockly.Blocks['text_prompt_ext'] = {
  /**
   * Block for prompt function (external message).
   * @this Blockly.Block
   */
  init: function() {
    var TYPES = [
      [Blockly.Msg.TEXT_PROMPT_TYPE_TEXT, 'TEXT'],
      [Blockly.Msg.TEXT_PROMPT_TYPE_NUMBER, 'NUMBER']
    ];
    this.setHelpUrl(Blockly.Msg.TEXT_PROMPT_HELPURL);
    this.setColour(Blockly.Blocks.texts.HUE);
    // Assign 'this' to a variable for use in the closures below.
    var thisBlock = this;
    var dropdown = new Blockly.FieldDropdown(TYPES, function(newOp) {
      thisBlock.updateType_(newOp);
    });
    this.appendValueInput('TEXT')
        .appendField(dropdown, 'TYPE');
    this.setOutput(true, 'String');
    this.setTooltip(function() {
      return (thisBlock.getFieldValue('TYPE') == 'TEXT') ?
          Blockly.Msg.TEXT_PROMPT_TOOLTIP_TEXT :
          Blockly.Msg.TEXT_PROMPT_TOOLTIP_NUMBER;
    });
  },
  /**
   * Modify this block to have the correct output type.
   * @param {string} newOp Either 'TEXT' or 'NUMBER'.
   * @private
   * @this Blockly.Block
   */
  updateType_: function(newOp) {
    this.outputConnection.setCheck(newOp == 'NUMBER' ? 'Number' : 'String');
  },
  /**
   * Create XML to represent the output type.
   * @return {!Element} XML storage element.
   * @this Blockly.Block
   */
  mutationToDom: function() {
    var container = document.createElement('mutation');
    container.setAttribute('type', this.getFieldValue('TYPE'));
    return container;
  },
  /**
   * Parse XML to restore the output type.
   * @param {!Element} xmlElement XML storage element.
   * @this Blockly.Block
   */
  domToMutation: function(xmlElement) {
    this.updateType_(xmlElement.getAttribute('type'));
  }
};

Blockly.Blocks['text_prompt'] = {
  /**
   * Block for prompt function (internal message).
   * The 'text_prompt_ext' block is preferred as it is more flexible.
   * @this Blockly.Block
   */
  init: function() {
    this.mixin(Blockly.Constants.Text.QUOTE_IMAGE_MIXIN);
    var TYPES = [
      [Blockly.Msg.TEXT_PROMPT_TYPE_TEXT, 'TEXT'],
      [Blockly.Msg.TEXT_PROMPT_TYPE_NUMBER, 'NUMBER']
    ];

    // Assign 'this' to a variable for use in the closures below.
    var thisBlock = this;
    this.setHelpUrl(Blockly.Msg.TEXT_PROMPT_HELPURL);
    this.setColour(Blockly.Blocks.texts.HUE);
    var dropdown = new Blockly.FieldDropdown(TYPES, function(newOp) {
      thisBlock.updateType_(newOp);
    });
    this.appendDummyInput()
        .appendField(dropdown, 'TYPE')
        .appendField(this.newQuote_(true))
        .appendField(new Blockly.FieldTextInput(''), 'TEXT')
        .appendField(this.newQuote_(false));
    this.setOutput(true, 'String');
    this.setTooltip(function() {
      return (thisBlock.getFieldValue('TYPE') == 'TEXT') ?
          Blockly.Msg.TEXT_PROMPT_TOOLTIP_TEXT :
          Blockly.Msg.TEXT_PROMPT_TOOLTIP_NUMBER;
    });
  },
  updateType_: Blockly.Blocks['text_prompt_ext'].updateType_,
  mutationToDom: Blockly.Blocks['text_prompt_ext'].mutationToDom,
  domToMutation: Blockly.Blocks['text_prompt_ext'].domToMutation
};

Blockly.Blocks['text_count'] = {
  /**
   * Block for counting how many times one string appears within another string.
   * @this Blockly.Block
   */
  init: function() {
    this.jsonInit({
      "message0": Blockly.Msg.TEXT_COUNT_MESSAGE0,
      "args0": [
        {
          "type": "input_value",
          "name": "SUB",
          "check": "String"
        },
        {
          "type": "input_value",
          "name": "TEXT",
          "check": "String"
        }
      ],
      "output": "Number",
      "inputsInline": true,
      "colour": Blockly.Blocks.texts.HUE,
      "tooltip": Blockly.Msg.TEXT_COUNT_TOOLTIP,
      "helpUrl": Blockly.Msg.TEXT_COUNT_HELPURL
    });
  }
};

Blockly.Blocks['text_replace'] = {
  /**
   * Block for replacing one string with another in the text.
   * @this Blockly.Block
   */
  init: function() {
    this.jsonInit({
      "message0": Blockly.Msg.TEXT_REPLACE_MESSAGE0,
      "args0": [
        {
          "type": "input_value",
          "name": "FROM",
          "check": "String"
        },
        {
          "type": "input_value",
          "name": "TO",
          "check": "String"
        },
        {
          "type": "input_value",
          "name": "TEXT",
          "check": "String"
        }
      ],
      "output": "String",
      "inputsInline": true,
      "colour": Blockly.Blocks.texts.HUE,
      "tooltip": Blockly.Msg.TEXT_REPLACE_TOOLTIP,
      "helpUrl": Blockly.Msg.TEXT_REPLACE_HELPURL
    });
  }
};

Blockly.Blocks['text_reverse'] = {
  /**
   * Block for reversing a string.
   * @this Blockly.Block
   */
  init: function() {
    this.jsonInit({
      "message0": Blockly.Msg.TEXT_REVERSE_MESSAGE0,
      "args0": [
        {
          "type": "input_value",
          "name": "TEXT",
          "check": "String"
        }
      ],
      "output": "String",
      "inputsInline": true,
      "colour": Blockly.Blocks.texts.HUE,
      "tooltip": Blockly.Msg.TEXT_REVERSE_TOOLTIP,
      "helpUrl": Blockly.Msg.TEXT_REVERSE_HELPURL
    });
  }
};

/**
 *
 * @mixin
 * @package
 * @readonly
 */
Blockly.Constants.Text.QUOTE_IMAGE_MIXIN = {
  /**
   * Image data URI of an LTR opening double quote (same as RTL closing couble quote).
   * @readonly
   */
  QUOTE_IMAGE_LEFT_DATAURI:
    'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAwAAAAKCAQAAAAqJXdxAAAAn0lEQVQI1z3OMa5BURSF4f/cQhAKjUQhuQmFNwGJEUi0RKN5rU7FHKhpjEH3TEMtkdBSCY1EIv8r7nFX9e29V7EBAOvu7RPjwmWGH/VuF8CyN9/OAdvqIXYLvtRaNjx9mMTDyo+NjAN1HNcl9ZQ5oQMM3dgDUqDo1l8DzvwmtZN7mnD+PkmLa+4mhrxVA9fRowBWmVBhFy5gYEjKMfz9AylsaRRgGzvZAAAAAElFTkSuQmCC',
  /**
   * Image data URI of an LTR closing double quote (same as RTL opening couble quote).
   * @readonly
   */
  QUOTE_IMAGE_RIGHT_DATAURI:
    'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAwAAAAKCAQAAAAqJXdxAAAAqUlEQVQI1z3KvUpCcRiA8ef9E4JNHhI0aFEacm1o0BsI0Slx8wa8gLauoDnoBhq7DcfWhggONDmJJgqCPA7neJ7p934EOOKOnM8Q7PDElo/4x4lFb2DmuUjcUzS3URnGib9qaPNbuXvBO3sGPHJDRG6fGVdMSeWDP2q99FQdFrz26Gu5Tq7dFMzUvbXy8KXeAj57cOklgA+u1B5AoslLtGIHQMaCVnwDnADZIFIrXsoXrgAAAABJRU5ErkJggg==',
  /**
   * Pixel width of QUOTE_IMAGE_LEFT_DATAURI and QUOTE_IMAGE_RIGHT_DATAURI.
   * @readonly
   */
  QUOTE_IMAGE_WIDTH: 12,
  /**
   * Pixel height of QUOTE_IMAGE_LEFT_DATAURI and QUOTE_IMAGE_RIGHT_DATAURI.
   * @readonly
   */
  QUOTE_IMAGE_HEIGHT: 12,

  /**
   * Inserts appropriate quote images before and after the named field.
   * @param {string} fieldName The name of the field to wrap with quotes.
   */
  quoteField_: function(fieldName) {
    for (var i = 0, input; input = this.inputList[i]; i++) {
      for (var j = 0, field; field = input.fieldRow[j]; j++) {
        if (fieldName == field.name) {
          input.insertFieldAt(j, this.newQuote_(true));
          input.insertFieldAt(j + 2, this.newQuote_(false));
          return;
        }
      }
    }
    console.warn('field named "' + fieldName + '" not found in ' + this.toDevString());
  },

  /**
   * A helper function that generates a FieldImage of an opening or
   * closing double quote. The selected quote will be adapted for RTL blocks.
   * @param {boolean} open If the image should be open quote (“ in LTR).
   *                       Otherwise, a closing quote is used (” in LTR).
   * @returns {!Blockly.FieldImage} The new field.
   */
  newQuote_: function(open) {
    var isLeft = this.RTL? !open : open;
    var dataUri = isLeft ?
      this.QUOTE_IMAGE_LEFT_DATAURI :
      this.QUOTE_IMAGE_RIGHT_DATAURI;
    return new Blockly.FieldImage(
      dataUri,
      this.QUOTE_IMAGE_WIDTH,
      this.QUOTE_IMAGE_HEIGHT,
      isLeft ? '\u201C' : '\u201D');
  }
};

/** Wraps TEXT field with images of double quote characters. */
Blockly.Constants.Text.TEXT_QUOTES_EXTENSION = function() {
  this.mixin(Blockly.Constants.Text.QUOTE_IMAGE_MIXIN);
  this.quoteField_('TEXT');
};

/**
 * Mixin for mutator functions in the 'text_join_mutator' extension.
 * @mixin
 * @augments Blockly.Block
 * @package
 */
Blockly.Constants.Text.TEXT_JOIN_MUTATOR_MIXIN = {
  /**
   * Create XML to represent number of text inputs.
   * @return {!Element} XML storage element.
   * @this Blockly.Block
   */
  mutationToDom: function() {
    var container = document.createElement('mutation');
    container.setAttribute('items', this.itemCount_);
    return container;
  },
  /**
   * Parse XML to restore the text inputs.
   * @param {!Element} xmlElement XML storage element.
   * @this Blockly.Block
   */
  domToMutation: function(xmlElement) {
    this.itemCount_ = parseInt(xmlElement.getAttribute('items'), 10);
    this.updateShape_();
  },
  /**
   * Populate the mutator's dialog with this block's components.
   * @param {!Blockly.Workspace} workspace Mutator's workspace.
   * @return {!Blockly.Block} Root block in mutator.
   * @this Blockly.Block
   */
  decompose: function(workspace) {
    var containerBlock = workspace.newBlock('text_create_join_container');
    containerBlock.initSvg();
    var connection = containerBlock.getInput('STACK').connection;
    for (var i = 0; i < this.itemCount_; i++) {
      var itemBlock = workspace.newBlock('text_create_join_item');
      itemBlock.initSvg();
      connection.connect(itemBlock.previousConnection);
      connection = itemBlock.nextConnection;
    }
    return containerBlock;
  },
  /**
   * Reconfigure this block based on the mutator dialog's components.
   * @param {!Blockly.Block} containerBlock Root block in mutator.
   * @this Blockly.Block
   */
  compose: function(containerBlock) {
    var itemBlock = containerBlock.getInputTargetBlock('STACK');
    // Count number of inputs.
    var connections = [];
    while (itemBlock) {
      connections.push(itemBlock.valueConnection_);
      itemBlock = itemBlock.nextConnection &&
          itemBlock.nextConnection.targetBlock();
    }
    // Disconnect any children that don't belong.
    for (var i = 0; i < this.itemCount_; i++) {
      var connection = this.getInput('ADD' + i).connection.targetConnection;
      if (connection && connections.indexOf(connection) == -1) {
        connection.disconnect();
      }
    }
    this.itemCount_ = connections.length;
    this.updateShape_();
    // Reconnect any child blocks.
    for (var i = 0; i < this.itemCount_; i++) {
      Blockly.Mutator.reconnect(connections[i], this, 'ADD' + i);
    }
  },
  /**
   * Store pointers to any connected child blocks.
   * @param {!Blockly.Block} containerBlock Root block in mutator.
   * @this Blockly.Block
   */
  saveConnections: function(containerBlock) {
    var itemBlock = containerBlock.getInputTargetBlock('STACK');
    var i = 0;
    while (itemBlock) {
      var input = this.getInput('ADD' + i);
      itemBlock.valueConnection_ = input && input.connection.targetConnection;
      i++;
      itemBlock = itemBlock.nextConnection &&
          itemBlock.nextConnection.targetBlock();
    }
  },
  /**
   * Modify this block to have the correct number of inputs.
   * @private
   * @this Blockly.Block
   */
  updateShape_: function() {
    if (this.itemCount_ && this.getInput('EMPTY')) {
      this.removeInput('EMPTY');
    } else if (!this.itemCount_ && !this.getInput('EMPTY')) {
      this.appendDummyInput('EMPTY')
          .appendField(this.newQuote_(true))
          .appendField(this.newQuote_(false));
    }
    // Add new inputs.
    for (var i = 0; i < this.itemCount_; i++) {
      if (!this.getInput('ADD' + i)) {
        var input = this.appendValueInput('ADD' + i);
        if (i == 0) {
          input.appendField(Blockly.Msg.TEXT_JOIN_TITLE_CREATEWITH);
        }
      }
    }
    // Remove deleted inputs.
    while (this.getInput('ADD' + i)) {
      this.removeInput('ADD' + i);
      i++;
    }
  }
};

// Performs final setup of a text_join block.
Blockly.Constants.Text.TEXT_JOIN_EXTENSION = function() {
  // Add the quote mixin for the itemCount_ = 0 case.
  this.mixin(Blockly.Constants.Text.QUOTE_IMAGE_MIXIN);
  // initialize the mutator values
  this.itemCount_ = 2;
  this.updateShape_();
  // Configure the mutator ui
  this.setMutator(new Blockly.Mutator(['text_create_join_item']));
};

Blockly.Constants.Text.TEXT_APPEND_TOOLTIP_EXTENSION = function() {
  // Assign 'this' to a variable for use in the tooltip closure below.
  var thisBlock = this;
  this.setTooltip(function() {
    if (Blockly.Msg.TEXT_APPEND_TOOLTIP) {
      return Blockly.Msg.TEXT_APPEND_TOOLTIP.replace('%1',
          thisBlock.getFieldValue('VAR'));
    }
    return '';
  });
};

Blockly.Constants.Text.TEXT_INDEXOF_TOOLTIP_EXTENSION = function() {
  // Assign 'this' to a variable for use in the tooltip closure below.
  var thisBlock = this;
  this.setTooltip(function() {
    return Blockly.Msg.TEXT_INDEXOF_TOOLTIP.replace('%1',
        thisBlock.workspace.options.oneBasedIndex ? '0' : '-1');
  });
};

/**
 * Mixin for mutator functions in the 'text_charAt_mutator' extension.
 * @mixin
 * @augments Blockly.Block
 * @package
 */
Blockly.Constants.Text.TEXT_CHARAT_MUTATOR_MIXIN = {
  /**
   * Create XML to represent whether there is an 'AT' input.
   * @return {!Element} XML storage element.
   * @this Blockly.Block
   */
  mutationToDom: function() {
    var container = document.createElement('mutation');
    var isAt = this.getInput('AT').type == Blockly.INPUT_VALUE;
    container.setAttribute('at', isAt);
    return container;
  },
  /**
   * Parse XML to restore the 'AT' input.
   * @param {!Element} xmlElement XML storage element.
   * @this Blockly.Block
   */
  domToMutation: function(xmlElement) {
    // Note: Until January 2013 this block did not have mutations,
    // so 'at' defaults to true.
    var isAt = (xmlElement.getAttribute('at') != 'false');
    this.updateAt_(isAt);
  },
  /**
   * Create or delete an input for the numeric index.
   * @param {boolean} isAt True if the input should exist.
   * @private
   * @this Blockly.Block
   */
  updateAt_: function(isAt) {
    // Destroy old 'AT' and 'ORDINAL' inputs.
    this.removeInput('AT');
    this.removeInput('ORDINAL', true);
    // Create either a value 'AT' input or a dummy input.
    if (isAt) {
      this.appendValueInput('AT').setCheck('Number');
      if (Blockly.Msg.ORDINAL_NUMBER_SUFFIX) {
        this.appendDummyInput('ORDINAL')
            .appendField(Blockly.Msg.ORDINAL_NUMBER_SUFFIX);
      }
    } else {
      this.appendDummyInput('AT');
    }
    if (Blockly.Msg.TEXT_CHARAT_TAIL) {
      this.removeInput('TAIL', true);
      this.appendDummyInput('TAIL')
          .appendField(Blockly.Msg.TEXT_CHARAT_TAIL);
    }
    var menu = new Blockly.FieldDropdown(this.WHERE_OPTIONS, function(value) {
      var newAt = (value == 'FROM_START') || (value == 'FROM_END');
      // The 'isAt' variable is available due to this function being a closure.
      if (newAt != isAt) {
        var block = this.sourceBlock_;
        block.updateAt_(newAt);
        // This menu has been destroyed and replaced.  Update the replacement.
        block.setFieldValue(value, 'WHERE');
        return null;
      }
      return undefined;
    });
    this.getInput('AT').appendField(menu, 'WHERE');
  }
};

// Does the initial mutator update of text_charAt and adds the tooltip
Blockly.Constants.Text.TEXT_CHARAT_EXTENSION = function() {
    this.WHERE_OPTIONS = [
        [Blockly.Msg.TEXT_CHARAT_FROM_START, 'FROM_START'],
        [Blockly.Msg.TEXT_CHARAT_FROM_END, 'FROM_END'],
        [Blockly.Msg.TEXT_CHARAT_FIRST, 'FIRST'],
        [Blockly.Msg.TEXT_CHARAT_LAST, 'LAST'],
        [Blockly.Msg.TEXT_CHARAT_RANDOM, 'RANDOM']
      ];
    this.updateAt_(true);
    // Assign 'this' to a variable for use in the tooltip closure below.
    var thisBlock = this;
    this.setTooltip(function() {
      var where = thisBlock.getFieldValue('WHERE');
      var tooltip = Blockly.Msg.TEXT_CHARAT_TOOLTIP;
      if (where == 'FROM_START' || where == 'FROM_END') {
        var msg = (where == 'FROM_START') ?
            Blockly.Msg.LISTS_INDEX_FROM_START_TOOLTIP :
            Blockly.Msg.LISTS_INDEX_FROM_END_TOOLTIP;
        if (msg) {
          tooltip += '  ' + msg.replace('%1',
              thisBlock.workspace.options.oneBasedIndex ? '#1' : '#0');
        }
      }
      return tooltip;
    });
};

Blockly.Extensions.register('text_indexOf_tooltip',
  Blockly.Constants.Text.TEXT_INDEXOF_TOOLTIP_EXTENSION);

Blockly.Extensions.register('text_quotes',
  Blockly.Constants.Text.TEXT_QUOTES_EXTENSION);

Blockly.Extensions.register('text_append_tooltip',
  Blockly.Constants.Text.TEXT_APPEND_TOOLTIP_EXTENSION);

Blockly.Extensions.registerMutator('text_join_mutator',
  Blockly.Constants.Text.TEXT_JOIN_MUTATOR_MIXIN,
  Blockly.Constants.Text.TEXT_JOIN_EXTENSION);

Blockly.Extensions.registerMutator('text_charAt_mutator',
  Blockly.Constants.Text.TEXT_CHARAT_MUTATOR_MIXIN,
  Blockly.Constants.Text.TEXT_CHARAT_EXTENSION);