text: /**
   * @license
   * Copyright 2014 Google LLC
   * SPDX-License-Identifier: Apache-2.0
   */
  
  /**
   * @fileoverview Generating Dart for logic blocks.
   * @author q.neutron@gmail.com (Quynh Neutron)
   */
  'use strict';
  
  goog.provide('Blockly.Dart.logic');
  
  goog.require('Blockly.Dart');
  
  
  Blockly.Dart['controls_if'] = function(block) {
    // If/elseif/else condition.
    var n = 0;
    var code = '', branchCode, conditionCode;
    if (Blockly.Dart.STATEMENT_PREFIX) {
      // Automatic prefix insertion is switched off for this block.  Add manually.
      code += Blockly.Dart.injectId(Blockly.Dart.STATEMENT_PREFIX, block);
    }
    do {
      conditionCode = Blockly.Dart.valueToCode(block, 'IF' + n,
          Blockly.Dart.ORDER_NONE) || 'false';
      branchCode = Blockly.Dart.statementToCode(block, 'DO' + n);
      if (Blockly.Dart.STATEMENT_SUFFIX) {
        branchCode = Blockly.Dart.prefixLines(
            Blockly.Dart.injectId(Blockly.Dart.STATEMENT_SUFFIX, block),
            Blockly.Dart.INDENT) + branchCode;
      }
      code += (n > 0 ? 'else ' : '') +
          'if (' + conditionCode + ') {\n' + branchCode + '}';
      ++n;
    } while (block.getInput('IF' + n));
  
    if (block.getInput('ELSE') || Blockly.Dart.STATEMENT_SUFFIX) {
      branchCode = Blockly.Dart.statementToCode(block, 'ELSE');
      if (Blockly.Dart.STATEMENT_SUFFIX) {
        branchCode = Blockly.Dart.prefixLines(
            Blockly.Dart.injectId(Blockly.Dart.STATEMENT_SUFFIX, block),
            Blockly.Dart.INDENT) + branchCode;
      }
      code += ' else {\n' + branchCode + '}';
    }
    return code + '\n';
  };
  
  Blockly.Dart['controls_ifelse'] = Blockly.Dart['controls_if'];
  
  Blockly.Dart['logic_compare'] = function(block) {
    // Comparison operator.
    var OPERATORS = {
      'EQ': '==',
      'NEQ': '!=',
      'LT': '<',
      'LTE': '<=',
      'GT': '>',
      'GTE': '>='
    };
    var operator = OPERATORS[block.getFieldValue('OP')];
    var order = (operator == '==' || operator == '!=') ?
        Blockly.Dart.ORDER_EQUALITY : Blockly.Dart.ORDER_RELATIONAL;
    var argument0 = Blockly.Dart.valueToCode(block, 'A', order) || '0';
    var argument1 = Blockly.Dart.valueToCode(block, 'B', order) || '0';
    var code = argument0 + ' ' + operator + ' ' + argument1;
    return [code, order];
  };
  
  Blockly.Dart['logic_operation'] = function(block) {
    // Operations 'and', 'or'.
    var operator = (block.getFieldValue('OP') == 'AND') ? '&&' : '||';
    var order = (operator == '&&') ? Blockly.Dart.ORDER_LOGICAL_AND :
        Blockly.Dart.ORDER_LOGICAL_OR;
    var argument0 = Blockly.Dart.valueToCode(block, 'A', order);
    var argument1 = Blockly.Dart.valueToCode(block, 'B', order);
    if (!argument0 && !argument1) {
      // If there are no arguments, then the return value is false.
      argument0 = 'false';
      argument1 = 'false';
    } else {
      // Single missing arguments have no effect on the return value.
      var defaultArgument = (operator == '&&') ? 'true' : 'false';
      if (!argument0) {
        argument0 = defaultArgument;
      }
      if (!argument1) {
        argument1 = defaultArgument;
      }
    }
    var code = argument0 + ' ' + operator + ' ' + argument1;
    return [code, order];
  };
  
  Blockly.Dart['logic_negate'] = function(block) {
    // Negation.
    var order = Blockly.Dart.ORDER_UNARY_PREFIX;
    var argument0 = Blockly.Dart.valueToCode(block, 'BOOL', order) || 'true';
    var code = '!' + argument0;
    return [code, order];
  };
  
  Blockly.Dart['logic_boolean'] = function(block) {
    // Boolean values true and false.
    var code = (block.getFieldValue('BOOL') == 'TRUE') ? 'true' : 'false';
    return [code, Blockly.Dart.ORDER_ATOMIC];
  };
  
  Blockly.Dart['logic_null'] = function(block) {
    // Null data type.
    return ['null', Blockly.Dart.ORDER_ATOMIC];
  };
  
  Blockly.Dart['logic_ternary'] = function(block) {
    // Ternary operator.
    var value_if = Blockly.Dart.valueToCode(block, 'IF',
        Blockly.Dart.ORDER_CONDITIONAL) || 'false';
    var value_then = Blockly.Dart.valueToCode(block, 'THEN',
        Blockly.Dart.ORDER_CONDITIONAL) || 'null';
    var value_else = Blockly.Dart.valueToCode(block, 'ELSE',
        Blockly.Dart.ORDER_CONDITIONAL) || 'null';
    var code = value_if + ' ? ' + value_then + ' : ' + value_else;
    return [code, Blockly.Dart.ORDER_CONDITIONAL];
  };
  