Blockly.Blocks['dicts_create_with'] = {
    /**
     * Block for creating a dict with any number of elements of any type.
     * @this Blockly.Block
     */
    init: function() {
        console.log("init");
        this.setInputsInline(false);
        this.setColour(Blockly.Blocks.dicts.HUE);
        this.itemCount_ = 1;
        this.updateShape_();
        this.setOutput(true, 'dict');
        this.setTooltip(Blockly.Msg.DICTS_CREATE_WITH_TOOLTIP);
    },
    /**
     * Create XML to represent dict inputs.
     * @return {Element} XML storage element.
     * @this Blockly.Block
     */
    mutationToDom: function(workspace) {
        var container = document.createElement('mutation');
        container.setAttribute('items', this.itemCount_);
        return container;
    },
    /**
     * Parse XML to restore the dict inputs.
     * @param {!Element} xmlElement XML storage element.
     * @this Blockly.Block
     */
    domToMutation: function(xmlElement) {
        this.itemCount_ = parseInt(xmlElement.getAttribute('items'), 10);
        this.updateShape_();
    },
    fixEmpty_: function() {
        if (this.itemCount_ > 0) {
            this.getInput("START").fieldRow[0].setText("dictionary of");
        } else {
            this.getInput("START").fieldRow[0].setText(Blockly.Msg.DICTS_CREATE_EMPTY_TITLE);
        }
    },
    addRow: function(i) {
        if (!this.getInput('VALUE'+i)) {
            this.appendValueInput('VALUE' + i)
                .setCheck(null)
                .setAlign(Blockly.ALIGN_RIGHT)
                .appendField(
                      new Blockly.FieldTextInput(
                          Blockly.Msg.DICTS_CREATE_WITH_ITEM_KEY),
                     'KEY'+i)
               .appendField(Blockly.Msg.DICTS_CREATE_WITH_ITEM_MAPPING);
        }
    },
    /**
     * Modify this block to have the correct number of inputs.
     * @private
     * @this Blockly.Block
     */
    updateShape_: function() {
        var that = this;
        function addField(field, block, e) {
            var rect = field.fieldGroup_.getBoundingClientRect();
            var yPosition = e.clientY;
            if (yPosition < rect.top+rect.height/2) {
                that.itemCount_ += 1;
                that.addRow(that.itemCount_);
            } else {
                if (that.itemCount_ > 0) {
                    that.removeInput('VALUE' + that.itemCount_);
                    that.itemCount_ -= 1;
                }
            }
            that.fixEmpty_();
        }
        var clickablePlusMinus = new Blockly.FieldClickImage("images/plus_minus_v.png", 24, 24, '+', addField, '-2px');
        // Rebuild block.
        if (!this.getInput("START")) {
            this.appendDummyInput('START')
                .appendField("dictionary of")
                .appendField(clickablePlusMinus);
        }
        this.fixEmpty_();
        for (var i = 1; i <= this.itemCount_; i++) {
            this.addRow(i);
        }
    }
};