text: /**
   * @license
   * Copyright 2015 Google LLC
   * SPDX-License-Identifier: Apache-2.0
   */
  
  /**
   * @fileoverview Generating PHP for math blocks.
   * @author daarond@gmail.com (Daaron Dwyer)
   */
  'use strict';
  
  goog.provide('Blockly.PHP.math');
  
  goog.require('Blockly.PHP');
  
  
  Blockly.PHP['math_number'] = function(block) {
    // Numeric value.
    var code = Number(block.getFieldValue('NUM'));
    var order = code >= 0 ? Blockly.PHP.ORDER_ATOMIC :
                Blockly.PHP.ORDER_UNARY_NEGATION;
    if (code == Infinity) {
      code = 'INF';
    } else if (code == -Infinity) {
      code = '-INF';
    }
    return [code, order];
  };
  
  Blockly.PHP['math_arithmetic'] = function(block) {
    // Basic arithmetic operators, and power.
    var OPERATORS = {
      'ADD': [' + ', Blockly.PHP.ORDER_ADDITION],
      'MINUS': [' - ', Blockly.PHP.ORDER_SUBTRACTION],
      'MULTIPLY': [' * ', Blockly.PHP.ORDER_MULTIPLICATION],
      'DIVIDE': [' / ', Blockly.PHP.ORDER_DIVISION],
      'POWER': [' ** ', Blockly.PHP.ORDER_POWER]
    };
    var tuple = OPERATORS[block.getFieldValue('OP')];
    var operator = tuple[0];
    var order = tuple[1];
    var argument0 = Blockly.PHP.valueToCode(block, 'A', order) || '0';
    var argument1 = Blockly.PHP.valueToCode(block, 'B', order) || '0';
    var code = argument0 + operator + argument1;
    return [code, order];
  };
  
  Blockly.PHP['math_single'] = function(block) {
    // Math operators with single operand.
    var operator = block.getFieldValue('OP');
    var code;
    var arg;
    if (operator == 'NEG') {
      // Negation is a special case given its different operator precedence.
      arg = Blockly.PHP.valueToCode(block, 'NUM',
          Blockly.PHP.ORDER_UNARY_NEGATION) || '0';
      if (arg[0] == '-') {
        // --3 is not legal in JS.
        arg = ' ' + arg;
      }
      code = '-' + arg;
      return [code, Blockly.PHP.ORDER_UNARY_NEGATION];
    }
    if (operator == 'SIN' || operator == 'COS' || operator == 'TAN') {
      arg = Blockly.PHP.valueToCode(block, 'NUM',
          Blockly.PHP.ORDER_DIVISION) || '0';
    } else {
      arg = Blockly.PHP.valueToCode(block, 'NUM',
          Blockly.PHP.ORDER_NONE) || '0';
    }
    // First, handle cases which generate values that don't need parentheses
    // wrapping the code.
    switch (operator) {
      case 'ABS':
        code = 'abs(' + arg + ')';
        break;
      case 'ROOT':
        code = 'sqrt(' + arg + ')';
        break;
      case 'LN':
        code = 'log(' + arg + ')';
        break;
      case 'EXP':
        code = 'exp(' + arg + ')';
        break;
      case 'POW10':
        code = 'pow(10,' + arg + ')';
        break;
      case 'ROUND':
        code = 'round(' + arg + ')';
        break;
      case 'ROUNDUP':
        code = 'ceil(' + arg + ')';
        break;
      case 'ROUNDDOWN':
        code = 'floor(' + arg + ')';
        break;
      case 'SIN':
        code = 'sin(' + arg + ' / 180 * pi())';
        break;
      case 'COS':
        code = 'cos(' + arg + ' / 180 * pi())';
        break;
      case 'TAN':
        code = 'tan(' + arg + ' / 180 * pi())';
        break;
    }
    if (code) {
      return [code, Blockly.PHP.ORDER_FUNCTION_CALL];
    }
    // Second, handle cases which generate values that may need parentheses
    // wrapping the code.
    switch (operator) {
      case 'LOG10':
        code = 'log(' + arg + ') / log(10)';
        break;
      case 'ASIN':
        code = 'asin(' + arg + ') / pi() * 180';
        break;
      case 'ACOS':
        code = 'acos(' + arg + ') / pi() * 180';
        break;
      case 'ATAN':
        code = 'atan(' + arg + ') / pi() * 180';
        break;
      default:
        throw Error('Unknown math operator: ' + operator);
    }
    return [code, Blockly.PHP.ORDER_DIVISION];
  };
  
  Blockly.PHP['math_constant'] = function(block) {
    // Constants: PI, E, the Golden Ratio, sqrt(2), 1/sqrt(2), INFINITY.
    var CONSTANTS = {
      'PI': ['M_PI', Blockly.PHP.ORDER_ATOMIC],
      'E': ['M_E', Blockly.PHP.ORDER_ATOMIC],
      'GOLDEN_RATIO': ['(1 + sqrt(5)) / 2', Blockly.PHP.ORDER_DIVISION],
      'SQRT2': ['M_SQRT2', Blockly.PHP.ORDER_ATOMIC],
      'SQRT1_2': ['M_SQRT1_2', Blockly.PHP.ORDER_ATOMIC],
      'INFINITY': ['INF', Blockly.PHP.ORDER_ATOMIC]
    };
    return CONSTANTS[block.getFieldValue('CONSTANT')];
  };
  
  Blockly.PHP['math_number_property'] = function(block) {
    // Check if a number is even, odd, prime, whole, positive, or negative
    // or if it is divisible by certain number. Returns true or false.
    var number_to_check = Blockly.PHP.valueToCode(block, 'NUMBER_TO_CHECK',
        Blockly.PHP.ORDER_MODULUS) || '0';
    var dropdown_property = block.getFieldValue('PROPERTY');
    var code;
    if (dropdown_property == 'PRIME') {
      // Prime is a special case as it is not a one-liner test.
      var functionName = Blockly.PHP.provideFunction_(
          'math_isPrime',
          ['function ' + Blockly.PHP.FUNCTION_NAME_PLACEHOLDER_ + '($n) {',
           '  // https://en.wikipedia.org/wiki/Primality_test#Naive_methods',
           '  if ($n == 2 || $n == 3) {',
           '    return true;',
           '  }',
           '  // False if n is NaN, negative, is 1, or not whole.',
           '  // And false if n is divisible by 2 or 3.',
           '  if (!is_numeric($n) || $n <= 1 || $n % 1 != 0 || $n % 2 == 0 ||' +
              ' $n % 3 == 0) {',
           '    return false;',
           '  }',
           '  // Check all the numbers of form 6k +/- 1, up to sqrt(n).',
           '  for ($x = 6; $x <= sqrt($n) + 1; $x += 6) {',
           '    if ($n % ($x - 1) == 0 || $n % ($x + 1) == 0) {',
           '      return false;',
           '    }',
           '  }',
           '  return true;',
           '}']);
      code = functionName + '(' + number_to_check + ')';
      return [code, Blockly.PHP.ORDER_FUNCTION_CALL];
    }
    switch (dropdown_property) {
      case 'EVEN':
        code = number_to_check + ' % 2 == 0';
        break;
      case 'ODD':
        code = number_to_check + ' % 2 == 1';
        break;
      case 'WHOLE':
        code = 'is_int(' + number_to_check + ')';
        break;
      case 'POSITIVE':
        code = number_to_check + ' > 0';
        break;
      case 'NEGATIVE':
        code = number_to_check + ' < 0';
        break;
      case 'DIVISIBLE_BY':
        var divisor = Blockly.PHP.valueToCode(block, 'DIVISOR',
            Blockly.PHP.ORDER_MODULUS) || '0';
        code = number_to_check + ' % ' + divisor + ' == 0';
        break;
    }
    return [code, Blockly.PHP.ORDER_EQUALITY];
  };
  
  Blockly.PHP['math_change'] = function(block) {
    // Add to a variable in place.
    var argument0 = Blockly.PHP.valueToCode(block, 'DELTA',
        Blockly.PHP.ORDER_ADDITION) || '0';
    var varName = Blockly.PHP.variableDB_.getName(
        block.getFieldValue('VAR'), Blockly.VARIABLE_CATEGORY_NAME);
    return varName + ' += ' + argument0 + ';\n';
  };
  
  // Rounding functions have a single operand.
  Blockly.PHP['math_round'] = Blockly.PHP['math_single'];
  // Trigonometry functions have a single operand.
  Blockly.PHP['math_trig'] = Blockly.PHP['math_single'];
  
  Blockly.PHP['math_on_list'] = function(block) {
    // Math functions for lists.
    var func = block.getFieldValue('OP');
    var list, code;
    switch (func) {
      case 'SUM':
        list = Blockly.PHP.valueToCode(block, 'LIST',
            Blockly.PHP.ORDER_FUNCTION_CALL) || 'array()';
        code = 'array_sum(' + list + ')';
        break;
      case 'MIN':
        list = Blockly.PHP.valueToCode(block, 'LIST',
            Blockly.PHP.ORDER_FUNCTION_CALL) || 'array()';
        code = 'min(' + list + ')';
        break;
      case 'MAX':
        list = Blockly.PHP.valueToCode(block, 'LIST',
            Blockly.PHP.ORDER_FUNCTION_CALL) || 'array()';
        code = 'max(' + list + ')';
        break;
      case 'AVERAGE':
        var functionName = Blockly.PHP.provideFunction_(
            'math_mean',
            ['function ' + Blockly.PHP.FUNCTION_NAME_PLACEHOLDER_ +
                '($myList) {',
             '  return array_sum($myList) / count($myList);',
             '}']);
        list = Blockly.PHP.valueToCode(block, 'LIST',
            Blockly.PHP.ORDER_NONE) || 'array()';
        code = functionName + '(' + list + ')';
        break;
      case 'MEDIAN':
        var functionName = Blockly.PHP.provideFunction_(
            'math_median',
            ['function ' + Blockly.PHP.FUNCTION_NAME_PLACEHOLDER_ +
                '($arr) {',
             '  sort($arr,SORT_NUMERIC);',
             '  return (count($arr) % 2) ? $arr[floor(count($arr)/2)] : ',
             '      ($arr[floor(count($arr)/2)] + $arr[floor(count($arr)/2)' +
                ' - 1]) / 2;',
             '}']);
        list = Blockly.PHP.valueToCode(block, 'LIST',
            Blockly.PHP.ORDER_NONE) || '[]';
        code = functionName + '(' + list + ')';
        break;
      case 'MODE':
        // As a list of numbers can contain more than one mode,
        // the returned result is provided as an array.
        // Mode of [3, 'x', 'x', 1, 1, 2, '3'] -> ['x', 1].
        var functionName = Blockly.PHP.provideFunction_(
            'math_modes',
            ['function ' + Blockly.PHP.FUNCTION_NAME_PLACEHOLDER_ +
                '($values) {',
             '  if (empty($values)) return array();',
             '  $counts = array_count_values($values);',
             '  arsort($counts); // Sort counts in descending order',
             '  $modes = array_keys($counts, current($counts), true);',
             '  return $modes;',
             '}']);
        list = Blockly.PHP.valueToCode(block, 'LIST',
            Blockly.PHP.ORDER_NONE) || '[]';
        code = functionName + '(' + list + ')';
        break;
      case 'STD_DEV':
        var functionName = Blockly.PHP.provideFunction_(
            'math_standard_deviation',
            ['function ' + Blockly.PHP.FUNCTION_NAME_PLACEHOLDER_ +
                '($numbers) {',
             '  $n = count($numbers);',
             '  if (!$n) return null;',
             '  $mean = array_sum($numbers) / count($numbers);',
             '  foreach($numbers as $key => $num) $devs[$key] = ' +
                'pow($num - $mean, 2);',
             '  return sqrt(array_sum($devs) / (count($devs) - 1));',
             '}']);
        list = Blockly.PHP.valueToCode(block, 'LIST',
                Blockly.PHP.ORDER_NONE) || '[]';
        code = functionName + '(' + list + ')';
        break;
      case 'RANDOM':
        var functionName = Blockly.PHP.provideFunction_(
            'math_random_list',
            ['function ' + Blockly.PHP.FUNCTION_NAME_PLACEHOLDER_ +
                '($list) {',
             '  $x = rand(0, count($list)-1);',
             '  return $list[$x];',
             '}']);
        list = Blockly.PHP.valueToCode(block, 'LIST',
            Blockly.PHP.ORDER_NONE) || '[]';
        code = functionName + '(' + list + ')';
        break;
      default:
        throw Error('Unknown operator: ' + func);
    }
    return [code, Blockly.PHP.ORDER_FUNCTION_CALL];
  };
  
  Blockly.PHP['math_modulo'] = function(block) {
    // Remainder computation.
    var argument0 = Blockly.PHP.valueToCode(block, 'DIVIDEND',
        Blockly.PHP.ORDER_MODULUS) || '0';
    var argument1 = Blockly.PHP.valueToCode(block, 'DIVISOR',
        Blockly.PHP.ORDER_MODULUS) || '0';
    var code = argument0 + ' % ' + argument1;
    return [code, Blockly.PHP.ORDER_MODULUS];
  };
  
  Blockly.PHP['math_constrain'] = function(block) {
    // Constrain a number between two limits.
    var argument0 = Blockly.PHP.valueToCode(block, 'VALUE',
        Blockly.PHP.ORDER_COMMA) || '0';
    var argument1 = Blockly.PHP.valueToCode(block, 'LOW',
        Blockly.PHP.ORDER_COMMA) || '0';
    var argument2 = Blockly.PHP.valueToCode(block, 'HIGH',
        Blockly.PHP.ORDER_COMMA) || 'Infinity';
    var code = 'min(max(' + argument0 + ', ' + argument1 + '), ' +
        argument2 + ')';
    return [code, Blockly.PHP.ORDER_FUNCTION_CALL];
  };
  
  Blockly.PHP['math_random_int'] = function(block) {
    // Random integer between [X] and [Y].
    var argument0 = Blockly.PHP.valueToCode(block, 'FROM',
        Blockly.PHP.ORDER_COMMA) || '0';
    var argument1 = Blockly.PHP.valueToCode(block, 'TO',
        Blockly.PHP.ORDER_COMMA) || '0';
    var functionName = Blockly.PHP.provideFunction_(
        'math_random_int',
        ['function ' + Blockly.PHP.FUNCTION_NAME_PLACEHOLDER_ +
            '($a, $b) {',
         '  if ($a > $b) {',
         '    return rand($b, $a);',
         '  }',
         '  return rand($a, $b);',
         '}']);
    var code = functionName + '(' + argument0 + ', ' + argument1 + ')';
    return [code, Blockly.PHP.ORDER_FUNCTION_CALL];
  };
  
  Blockly.PHP['math_random_float'] = function(block) {
    // Random fraction between 0 and 1.
    return ['(float)rand()/(float)getrandmax()', Blockly.PHP.ORDER_FUNCTION_CALL];
  };
  
  Blockly.PHP['math_atan2'] = function(block) {
    // Arctangent of point (X, Y) in degrees from -180 to 180.
    var argument0 = Blockly.PHP.valueToCode(block, 'X',
        Blockly.PHP.ORDER_COMMA) || '0';
    var argument1 = Blockly.PHP.valueToCode(block, 'Y',
        Blockly.PHP.ORDER_COMMA) || '0';
    return ['atan2(' + argument1 + ', ' + argument0 + ') / pi() * 180',
        Blockly.PHP.ORDER_DIVISION];
  };
  