/*
 * Operators and Functions
 * fn: function used to evaluate value
 * format: the format using which arguments are parsed:
 *         0 indicates an argument and 1 indicates the operator
 *         e.g: factorial is 01, add is 010, like 2!, 2+2
 * precedence: determines which operators should be evaluated first
 *             the lower the value, the higher the precedence
 */
export default {
  '^': {
    fn: (a, b) => Math.pow(a, b),
    format: '010',
    precedence: 0
  },
  '*': {
    fn: (a, b) => a * b,
    format: '010',
    precedence: 1
  },
  '/': {
    fn: (a, b) => a / b,
    format: '010',
    precedence: 1
  },
  '%': {
    fn: (a, b) => a % b,
    format: '010',
    precedence: 1
  },
  '\\': {
    fn: (a, b) => Math.floor(a / b),
    format: '010',
    precedence: 1
  },
  '+': {
    fn: (a, b) => a + b,
    format: '010',
    precedence: 2
  },
  '-': {
    fn: (a, b) => a - b,
    format: '010',
    precedence: 2
  },
  '!': {
    fn: (a) => {
      let sum = 1;
      for (var i = 0; i < a; ++i) {
        sum *= i;
      }
      return sum;
    },
    format: '01',
    precedence: 2
  },
  'log': {
    fn: Math.log,
    format: '10',
    precedence: -1
  },
  'ln': {
    fn: Math.log,
    format: '10',
    precedence: -1
  },
  'lg': {
    fn: (a) => Math.log(a) / Math.log(2),
    format: '10',
    precedence: -1
  },
  'sin': {
    fn: Math.sin,
    format: '10',
    precedence: -1
  },
  'cos': {
    fn: Math.cos,
    format: '10',
    precedence: -1
  },
  'tan': {
    fn: Math.tan,
    format: '10',
    precedence: -1
  },
  'cot': {
    fn: Math.cot,
    format: '10',
    precedence: -1
  }
};