text: /**
   * @license
   * Visual Blocks Editor
   *
   * Copyright 2011 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 Core JavaScript library for Blockly.
   * @author fraser@google.com (Neil Fraser)
   */
  'use strict';
  
  /**
   * The top level namespace used to access the Blockly library.
   * @namespace Blockly
   **/
  goog.provide('Blockly');
  
  goog.require('Blockly.BlockSvg.render');
  goog.require('Blockly.DropDownDiv');
  goog.require('Blockly.Events');
  goog.require('Blockly.FieldAngle');
  goog.require('Blockly.FieldCheckbox');
  goog.require('Blockly.FieldColour');
  goog.require('Blockly.FieldColourSlider');
  // Date picker commented out since it increases footprint by 60%.
  // Add it only if you need it.
  //goog.require('Blockly.FieldDate');
  goog.require('Blockly.FieldDropdown');
  goog.require('Blockly.FieldIconMenu');
  goog.require('Blockly.FieldImage');
  goog.require('Blockly.FieldNote');
  goog.require('Blockly.FieldTextInput');
  goog.require('Blockly.FieldTextInputRemovable');
  goog.require('Blockly.FieldTextDropdown');
  goog.require('Blockly.FieldNumber');
  goog.require('Blockly.FieldNumberDropdown');
  goog.require('Blockly.FieldMatrix');
  goog.require('Blockly.FieldGANPaint');
  goog.require('Blockly.FieldVariable');
  goog.require('Blockly.FieldVerticalSeparator');
  goog.require('Blockly.Generator');
  goog.require('Blockly.Msg');
  goog.require('Blockly.Procedures');
  goog.require('Blockly.ScratchMsgs');
  goog.require('Blockly.Toolbox');
  goog.require('Blockly.Touch');
  goog.require('Blockly.WidgetDiv');
  goog.require('Blockly.WorkspaceSvg');
  goog.require('Blockly.constants');
  goog.require('Blockly.inject');
  goog.require('Blockly.utils');
  goog.require('goog.color');
  
  
  // Turn off debugging when compiled.
  /* eslint-disable no-unused-vars */
  var CLOSURE_DEFINES = {'goog.DEBUG': false};
  /* eslint-enable no-unused-vars */
  
  /**
   * The main workspace most recently used.
   * Set by Blockly.WorkspaceSvg.prototype.markFocused
   * @type {Blockly.Workspace}
   */
  Blockly.mainWorkspace = null;
  
  /**
   * Currently selected block.
   * @type {Blockly.Block}
   */
  Blockly.selected = null;
  
  /**
   * All of the connections on blocks that are currently being dragged.
   * @type {!Array.<!Blockly.Connection>}
   * @private
   */
  Blockly.draggingConnections_ = [];
  
  /**
   * Contents of the local clipboard.
   * @type {Element}
   * @private
   */
  Blockly.clipboardXml_ = null;
  
  /**
   * Source of the local clipboard.
   * @type {Blockly.WorkspaceSvg}
   * @private
   */
  Blockly.clipboardSource_ = null;
  
  /**
   * Cached value for whether 3D is supported.
   * @type {!boolean}
   * @private
   */
  Blockly.cache3dSupported_ = null;
  
  /**
   * Convert a hue (HSV model) into an RGB hex triplet.
   * @param {number} hue Hue on a colour wheel (0-360).
   * @return {string} RGB code, e.g. '#5ba65b'.
   */
  Blockly.hueToRgb = function(hue) {
    return goog.color.hsvToHex(hue, Blockly.HSV_SATURATION,
        Blockly.HSV_VALUE * 255);
  };
  
  /**
   * Returns the dimensions of the specified SVG image.
   * @param {!Element} svg SVG image.
   * @return {!Object} Contains width and height properties.
   */
  Blockly.svgSize = function(svg) {
    return {
      width: svg.cachedWidth_,
      height: svg.cachedHeight_
    };
  };
  
  /**
   * Size the workspace when the contents change.  This also updates
   * scrollbars accordingly.
   * @param {!Blockly.WorkspaceSvg} workspace The workspace to resize.
   */
  Blockly.resizeSvgContents = function(workspace) {
    workspace.resizeContents();
  };
  
  /**
   * Size the SVG image to completely fill its container. Call this when the view
   * actually changes sizes (e.g. on a window resize/device orientation change).
   * See Blockly.resizeSvgContents to resize the workspace when the contents
   * change (e.g. when a block is added or removed).
   * Record the height/width of the SVG image.
   * @param {!Blockly.WorkspaceSvg} workspace Any workspace in the SVG.
   */
  Blockly.svgResize = function(workspace) {
    var mainWorkspace = workspace;
    while (mainWorkspace.options.parentWorkspace) {
      mainWorkspace = mainWorkspace.options.parentWorkspace;
    }
    var svg = mainWorkspace.getParentSvg();
    var div = svg.parentNode;
    if (!div) {
      // Workspace deleted, or something.
      return;
    }
    var width = div.offsetWidth;
    var height = div.offsetHeight;
    if (svg.cachedWidth_ != width) {
      svg.setAttribute('width', width + 'px');
      svg.cachedWidth_ = width;
    }
    if (svg.cachedHeight_ != height) {
      svg.setAttribute('height', height + 'px');
      svg.cachedHeight_ = height;
    }
    mainWorkspace.resize();
  };
  
  /**
   * Handle a key-down on SVG drawing surface. Does nothing if the main workspace is not visible.
   * @param {!Event} e Key down event.
   * @private
   */
  // TODO (https://github.com/google/blockly/issues/1998) handle cases where there are multiple workspaces
  // and non-main workspaces are able to accept input.
  Blockly.onKeyDown_ = function(e) {
    if (Blockly.mainWorkspace.options.readOnly || Blockly.utils.isTargetInput(e)
        || (Blockly.mainWorkspace.rendered && !Blockly.mainWorkspace.isVisible())) {
      // No key actions on readonly workspaces.
      // When focused on an HTML text input widget, don't trap any keys.
      // Ignore keypresses on rendered workspaces that have been explicitly
      // hidden.
      return;
    }
    var deleteBlock = false;
    if (e.keyCode == 27) {
      // Pressing esc closes the context menu and any drop-down
      Blockly.hideChaff();
      Blockly.DropDownDiv.hide();
    } else if (e.keyCode == 8 || e.keyCode == 46) {
      // Delete or backspace.
      // Stop the browser from going back to the previous page.
      // Do this first to prevent an error in the delete code from resulting in
      // data loss.
      e.preventDefault();
      // Don't delete while dragging.  Jeez.
      if (Blockly.mainWorkspace.isDragging()) {
        return;
      }
      if (Blockly.selected && Blockly.selected.isDeletable()) {
        deleteBlock = true;
      }
    } else if (e.altKey || e.ctrlKey || e.metaKey) {
      // Don't use meta keys during drags.
      if (Blockly.mainWorkspace.isDragging()) {
        return;
      }
      if (Blockly.selected &&
          Blockly.selected.isDeletable() && Blockly.selected.isMovable()) {
        // Don't allow copying immovable or undeletable blocks. The next step
        // would be to paste, which would create additional undeletable/immovable
        // blocks on the workspace.
        if (e.keyCode == 67) {
          // 'c' for copy.
          Blockly.hideChaff();
          Blockly.copy_(Blockly.selected);
        } else if (e.keyCode == 88 && !Blockly.selected.workspace.isFlyout) {
          // 'x' for cut, but not in a flyout.
          // Don't even copy the selected item in the flyout.
          Blockly.copy_(Blockly.selected);
          deleteBlock = true;
        }
      }
      if (e.keyCode == 86) {
        // 'v' for paste.
        if (Blockly.clipboardXml_) {
          Blockly.Events.setGroup(true);
          // Pasting always pastes to the main workspace, even if the copy started
          // in a flyout workspace.
          var workspace = Blockly.clipboardSource_;
          if (workspace.isFlyout) {
            workspace = workspace.targetWorkspace;
          }
          workspace.paste(Blockly.clipboardXml_);
          Blockly.Events.setGroup(false);
        }
      } else if (e.keyCode == 90) {
        // 'z' for undo 'Z' is for redo.
        Blockly.hideChaff();
        Blockly.mainWorkspace.undo(e.shiftKey);
      }
    }
    // Common code for delete and cut.
    // Don't delete in the flyout.
    if (deleteBlock && !Blockly.selected.workspace.isFlyout) {
      Blockly.Events.setGroup(true);
      Blockly.hideChaff();
      Blockly.selected.dispose(/* heal */ true, true);
      Blockly.Events.setGroup(false);
    }
  };
  
  /**
   * Copy a block or workspace comment onto the local clipboard.
   * @param {!Blockly.Block | !Blockly.WorkspaceComment} toCopy Block or Workspace Comment
   *    to be copied.
   * @private
   */
  Blockly.copy_ = function(toCopy) {
    if (toCopy.isComment) {
      var xml = toCopy.toXmlWithXY();
    } else {
      var xml = Blockly.Xml.blockToDom(toCopy);
      // Encode start position in XML.
      var xy = toCopy.getRelativeToSurfaceXY();
      xml.setAttribute('x', toCopy.RTL ? -xy.x : xy.x);
      xml.setAttribute('y', xy.y);
    }
    Blockly.clipboardXml_ = xml;
    Blockly.clipboardSource_ = toCopy.workspace;
  };
  
  /**
   * Duplicate this block and its children, or a workspace comment.
   * @param {!Blockly.Block | !Blockly.WorkspaceComment} toDuplicate Block or
   *     Workspace Comment to be copied.
   * @private
   */
  Blockly.duplicate_ = function(toDuplicate) {
    // Save the clipboard.
    var clipboardXml = Blockly.clipboardXml_;
    var clipboardSource = Blockly.clipboardSource_;
  
    // Create a duplicate via a copy/paste operation.
    Blockly.copy_(toDuplicate);
    toDuplicate.workspace.paste(Blockly.clipboardXml_);
  
    // Restore the clipboard.
    Blockly.clipboardXml_ = clipboardXml;
    Blockly.clipboardSource_ = clipboardSource;
  };
  
  /**
   * Cancel the native context menu, unless the focus is on an HTML input widget.
   * @param {!Event} e Mouse down event.
   * @private
   */
  Blockly.onContextMenu_ = function(e) {
    if (!Blockly.utils.isTargetInput(e)) {
      // When focused on an HTML text input widget, don't cancel the context menu.
      e.preventDefault();
    }
  };
  
  /**
   * Close tooltips, context menus, dropdown selections, etc.
   * @param {boolean=} opt_allowToolbox If true, don't close the toolbox.
   */
  Blockly.hideChaff = function(opt_allowToolbox) {
    Blockly.hideChaffInternal_(opt_allowToolbox);
    Blockly.WidgetDiv.hide(true);
  };
  
  /**
   * Close tooltips, context menus, dropdown selections, etc.
   * For some elements (e.g. field text inputs), rather than hiding, it will
   * move them.
   * @param {boolean=} opt_allowToolbox If true, don't close the toolbox.
   */
  Blockly.hideChaffOnResize = function(opt_allowToolbox) {
    Blockly.hideChaffInternal_(opt_allowToolbox);
    Blockly.WidgetDiv.repositionForWindowResize();
  };
  
  /**
   * Does a majority of the work for hideChaff including tooltips, dropdowns,
   * toolbox, etc. It does not deal with the WidgetDiv.
   * @param {boolean=} opt_allowToolbox If true, don't close the toolbox.
   * @private
   */
  Blockly.hideChaffInternal_ = function(opt_allowToolbox) {
    Blockly.Tooltip.hide();
    Blockly.DropDownDiv.hideWithoutAnimation();
    if (!opt_allowToolbox) {
      var workspace = Blockly.getMainWorkspace();
      if (workspace.toolbox_ &&
          workspace.toolbox_.flyout_ &&
          workspace.toolbox_.flyout_.autoClose) {
        workspace.toolbox_.clearSelection();
      }
    }
  };
  
  /**
   * Returns the main workspace.  Returns the last used main workspace (based on
   * focus).  Try not to use this function, particularly if there are multiple
   * Blockly instances on a page.
   * @return {!Blockly.Workspace} The main workspace.
   */
  Blockly.getMainWorkspace = function() {
    return Blockly.mainWorkspace;
  };
  
  /**
   * Wrapper to window.alert() that app developers may override to
   * provide alternatives to the modal browser window.
   * @param {string} message The message to display to the user.
   * @param {function()=} opt_callback The callback when the alert is dismissed.
   */
  Blockly.alert = function(message, opt_callback) {
    window.alert(message);
    if (opt_callback) {
      opt_callback();
    }
  };
  
  /**
   * Wrapper to window.confirm() that app developers may override to
   * provide alternatives to the modal browser window.
   * @param {string} message The message to display to the user.
   * @param {!function(boolean)} callback The callback for handling user response.
   */
  Blockly.confirm = function(message, callback) {
    callback(window.confirm(message));
  };
  
  /**
   * Wrapper to window.prompt() that app developers may override to provide
   * alternatives to the modal browser window. Built-in browser prompts are
   * often used for better text input experience on mobile device. We strongly
   * recommend testing mobile when overriding this.
   * @param {string} message The message to display to the user.
   * @param {string} defaultValue The value to initialize the prompt with.
   * @param {!function(string)} callback The callback for handling user response.
   * @param {?string} _opt_title An optional title for the prompt.
   * @param {?string} _opt_varType An optional variable type for variable specific
   *     prompt behavior.
   */
  Blockly.prompt = function(message, defaultValue, callback, _opt_title,
      _opt_varType) {
    // opt_title and opt_varType are unused because we only need them to pass
    // information to the scratch-gui, which overwrites this function
    callback(window.prompt(message, defaultValue));
  };
  
  /**
   * A callback for status buttons. The window.alert is here for testing and
   * should be overridden.
   * @param {string} id An identifier.
   */
  Blockly.statusButtonCallback = function(id) {
    window.alert('status button was pressed for ' + id);
  };
  
  /**
   * Refresh the visual state of a status button in all extension category headers.
   * @param {Blockly.Workspace} workspace A workspace.
   */
  Blockly.refreshStatusButtons = function(workspace) {
    var buttons = workspace.getFlyout().buttons_;
    for (var i = 0; i < buttons.length; i++) {
      if (buttons[i] instanceof Blockly.FlyoutExtensionCategoryHeader) {
        buttons[i].refreshStatus();
      }
    }
  };
  
  /**
   * Helper function for defining a block from JSON.  The resulting function has
   * the correct value of jsonDef at the point in code where jsonInit is called.
   * @param {!Object} jsonDef The JSON definition of a block.
   * @return {function()} A function that calls jsonInit with the correct value
   *     of jsonDef.
   * @private
   */
  Blockly.jsonInitFactory_ = function(jsonDef) {
    return function() {
      this.jsonInit(jsonDef);
    };
  };
  
  /**
   * Define blocks from an array of JSON block definitions, as might be generated
   * by the Blockly Developer Tools.
   * @param {!Array.<!Object>} jsonArray An array of JSON block definitions.
   */
  Blockly.defineBlocksWithJsonArray = function(jsonArray) {
    for (var i = 0; i < jsonArray.length; i++) {
      var elem = jsonArray[i];
      if (!elem) {
        console.warn(
            'Block definition #' + i + ' in JSON array is ' + elem + '. ' +
            'Skipping.');
      } else {
        var typename = elem.type;
        if (typename == null || typename === '') {
          console.warn(
              'Block definition #' + i +
              ' in JSON array is missing a type attribute. Skipping.');
        } else {
          if (Blockly.Blocks[typename]) {
            console.warn(
                'Block definition #' + i + ' in JSON array' +
                ' overwrites prior definition of "' + typename + '".');
          }
          Blockly.Blocks[typename] = {
            init: Blockly.jsonInitFactory_(elem)
          };
        }
      }
    }
  };
  
  /**
   * Bind an event to a function call.  When calling the function, verifies that
   * it belongs to the touch stream that is currently being processed, and splits
   * multitouch events into multiple events as needed.
   * @param {!EventTarget} node Node upon which to listen.
   * @param {string} name Event name to listen to (e.g. 'mousedown').
   * @param {Object} thisObject The value of 'this' in the function.
   * @param {!Function} func Function to call when event is triggered.
   * @param {boolean=} opt_noCaptureIdentifier True if triggering on this event
   *     should not block execution of other event handlers on this touch or other
   *     simultaneous touches.
   * @param {boolean=} opt_noPreventDefault True if triggering on this event
   *     should prevent the default handler.  False by default.  If
   *     opt_noPreventDefault is provided, opt_noCaptureIdentifier must also be
   *     provided.
   * @return {!Array.<!Array>} Opaque data that can be passed to unbindEvent_.
   */
  Blockly.bindEventWithChecks_ = function(node, name, thisObject, func,
      opt_noCaptureIdentifier, opt_noPreventDefault) {
    var handled = false;
    var wrapFunc = function(e) {
      var captureIdentifier = !opt_noCaptureIdentifier;
      // Handle each touch point separately.  If the event was a mouse event, this
      // will hand back an array with one element, which we're fine handling.
      var events = Blockly.Touch.splitEventByTouches(e);
      for (var i = 0, event; event = events[i]; i++) {
        if (captureIdentifier && !Blockly.Touch.shouldHandleEvent(event)) {
          continue;
        }
        Blockly.Touch.setClientFromTouch(event);
        if (thisObject) {
          func.call(thisObject, event);
        } else {
          func(event);
        }
        handled = true;
      }
    };
  
    node.addEventListener(name, wrapFunc, false);
    var bindData = [[node, name, wrapFunc]];
  
    // Add equivalent touch event.
    if (name in Blockly.Touch.TOUCH_MAP) {
      var touchWrapFunc = function(e) {
        wrapFunc(e);
        // Calling preventDefault stops the browser from scrolling/zooming the
        // page.
        var preventDef = !opt_noPreventDefault;
        if (handled && preventDef) {
          e.preventDefault();
        }
      };
      for (var i = 0, type; type = Blockly.Touch.TOUCH_MAP[name][i]; i++) {
        node.addEventListener(type, touchWrapFunc, false);
        bindData.push([node, type, touchWrapFunc]);
      }
    }
    return bindData;
  };
  
  
  /**
   * Bind an event to a function call.  Handles multitouch events by using the
   * coordinates of the first changed touch, and doesn't do any safety checks for
   * simultaneous event processing.
   * @deprecated in favor of bindEventWithChecks_, but preserved for external
   * users.
   * @param {!EventTarget} node Node upon which to listen.
   * @param {string} name Event name to listen to (e.g. 'mousedown').
   * @param {Object} thisObject The value of 'this' in the function.
   * @param {!Function} func Function to call when event is triggered.
   * @return {!Array.<!Array>} Opaque data that can be passed to unbindEvent_.
   * @private
   */
  Blockly.bindEvent_ = function(node, name, thisObject, func) {
    var wrapFunc = function(e) {
      if (thisObject) {
        func.call(thisObject, e);
      } else {
        func(e);
      }
    };
  
    node.addEventListener(name, wrapFunc, false);
    var bindData = [[node, name, wrapFunc]];
  
    // Add equivalent touch event.
    if (name in Blockly.Touch.TOUCH_MAP) {
      var touchWrapFunc = function(e) {
        // Punt on multitouch events.
        if (e.changedTouches.length == 1) {
          // Map the touch event's properties to the event.
          var touchPoint = e.changedTouches[0];
          e.clientX = touchPoint.clientX;
          e.clientY = touchPoint.clientY;
        }
        wrapFunc(e);
  
        // Stop the browser from scrolling/zooming the page.
        e.preventDefault();
      };
      for (var i = 0, type; type = Blockly.Touch.TOUCH_MAP[name][i]; i++) {
        node.addEventListener(type, touchWrapFunc, false);
        bindData.push([node, type, touchWrapFunc]);
      }
    }
    return bindData;
  };
  
  /**
   * Unbind one or more events event from a function call.
   * @param {!Array.<!Array>} bindData Opaque data from bindEvent_.
   *     This list is emptied during the course of calling this function.
   * @return {!Function} The function call.
   * @private
   */
  Blockly.unbindEvent_ = function(bindData) {
    while (bindData.length) {
      var bindDatum = bindData.pop();
      var node = bindDatum[0];
      var name = bindDatum[1];
      var func = bindDatum[2];
      node.removeEventListener(name, func, false);
    }
    return func;
  };
  
  /**
   * Is the given string a number (includes negative and decimals).
   * @param {string} str Input string.
   * @return {boolean} True if number, false otherwise.
   */
  Blockly.isNumber = function(str) {
    return !!str.match(/^\s*-?\d+(\.\d+)?\s*$/);
  };
  
  // IE9 does not have a console.  Create a stub to stop errors.
  if (!goog.global['console']) {
    goog.global['console'] = {
      'log': function() {},
      'warn': function() {}
    };
  }
  
  // Export symbols that would otherwise be renamed by Closure compiler.
  if (!goog.global['Blockly']) {
    goog.global['Blockly'] = {};
  }
  goog.global['Blockly']['getMainWorkspace'] = Blockly.getMainWorkspace;
  