/**
 * @module Data
 * @submodule Utility Functions
 * @for p5
 * @requires core
 */

function utilityFunctions(p5, fn){
  /**
   * Converts a `Number` into a `String` with a given number of digits.
   *
   * `nf()` converts numbers such as `123.45` into strings formatted with a set
   * number of digits, as in `'123.4500'`.
   *
   * The first parameter, `num`, is the number to convert to a string. For
   * example, calling `nf(123.45)` returns the string `'123.45'`. If an array of
   * numbers is passed, as in `nf([123.45, 67.89])`, an array of formatted
   * strings will be returned.
   *
   * The second parameter, `left`, is optional. If a number is passed, as in
   * `nf(123.45, 4)`, it sets the minimum number of digits to include to the
   * left of the decimal place. If `left` is larger than the number of digits in
   * `num`, then unused digits will be set to 0. For example, calling
   * `nf(123.45, 4)` returns the string `'0123.45'`.
   *
   * The third parameter, `right`, is also optional. If a number is passed, as
   * in `nf(123.45, 4, 1)`, it sets the minimum number of digits to include to
   * the right of the decimal place. If `right` is smaller than the number of
   * decimal places in `num`, then `num` will be rounded to the given number of
   * decimal places. For example, calling `nf(123.45, 4, 1)` returns the string
   * `'0123.5'`. If right is larger than the number of decimal places in `num`,
   * then unused decimal places will be set to 0. For example, calling
   * `nf(123.45, 4, 3)` returns the string `'0123.450'`.
   *
   * When the number is negative, for example, calling `nf(-123.45, 5, 2)`
   * returns the string `'-00123.45'`.
   *
   * @method nf
   * @param {Number|String} num number to format.
   * @param {Integer|String} [left] number of digits to include to the left of
   *                                the decimal point.
   * @param {Integer|String} [right] number of digits to include to the right
   *                                 of the decimal point.
   * @return {String} formatted string.
   *
   * @example
   * function setup() {
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Style the text.
   *   textAlign(LEFT, CENTER);
   *   textSize(16);
   *
   *   // Create a number variable.
   *   let number = 123.45;
   *
   *   // Display the number as a string.
   *   let formatted = nf(number);
   *   text(formatted, 20, 20);
   *
   *   let negative = nf(-number, 4, 2);
   *   text(negative, 20, 40);
   *
   *   // Display the number with four digits
   *   // to the left of the decimal.
   *   let left = nf(number, 4);
   *   text(left, 20, 60);
   *
   *   // Display the number with four digits
   *   // to the left of the decimal and one
   *   // to the right.
   *   let right = nf(number, 4, 1);
   *   text(right, 20, 80);
   *
   *   describe(
   *     'The numbers "123.45", "-0123.45", "0123.45", and "0123.5" written on four separate lines. The text is in black on a gray background.'
   *   );
   * }
   */
  /**
   * @method nf
   * @param {Number[]} nums numbers to format.
   * @param {Integer|String} [left]
   * @param {Integer|String} [right]
   * @return {String[]} formatted strings.
   */
  fn.nf = function(nums, left, right) {
    // p5._validateParameters('nf', arguments);
    if (nums instanceof Array) {
      return nums.map(x => doNf(x, left, right));
    } else {
      const typeOfFirst = Object.prototype.toString.call(nums);
      if (typeOfFirst === '[object Arguments]') {
        if (nums.length === 3) {
          return this.nf(nums[0], nums[1], nums[2]);
        } else if (nums.length === 2) {
          return this.nf(nums[0], nums[1]);
        } else {
          return this.nf(nums[0]);
        }
      } else {
        return doNf(nums, left, right);
      }
    }
  };

  function doNf(num, left, right) {
    let isNegative = num < 0;
    num = Math.abs(num);
    let [leftPart, rightPart] = num.toString().split('.');

    if (typeof right === 'undefined') {
      leftPart = leftPart.padStart(left, '0');
      let result = rightPart ? leftPart + '.' + rightPart : leftPart;
      return isNegative ? '-' + result : result;
    } else {
      let roundedOff = num.toFixed(right);
      [leftPart, rightPart] = roundedOff.toString().split('.');
      leftPart = leftPart.padStart(left, '0');
      let result = typeof rightPart === 'undefined' ? leftPart : leftPart + '.' + rightPart;
      return isNegative ? '-' + result : result;
    }
  }

  /**
   * Converts a `Number` into a `String` with commas to mark units of 1,000.
   *
   * `nfc()` converts numbers such as 12345 into strings formatted with commas
   * to mark the thousands place, as in `'12,345'`.
   *
   * The first parameter, `num`, is the number to convert to a string. For
   * example, calling `nfc(12345)` returns the string `'12,345'`.
   *
   * The second parameter, `right`, is optional. If a number is passed, as in
   * `nfc(12345, 1)`, it sets the minimum number of digits to include to the
   * right of the decimal place. If `right` is smaller than the number of
   * decimal places in `num`, then `num` will be rounded to the given number of
   * decimal places. For example, calling `nfc(12345.67, 1)` returns the string
   * `'12,345.7'`. If `right` is larger than the number of decimal places in
   * `num`, then unused decimal places will be set to 0. For example, calling
   * `nfc(12345.67, 3)` returns the string `'12,345.670'`.
   *
   * @method nfc
   * @param  {Number|String} num number to format.
   * @param  {Integer|String} [right] number of digits to include to the right
   *                                  of the decimal point.
   * @return {String} formatted string.
   *
   * @example
   * function setup() {
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Style the text.
   *   textAlign(LEFT, CENTER);
   *   textSize(16);
   *
   *   // Create a number variable.
   *   let number = 12345;
   *
   *   // Display the number as a string.
   *   let commas = nfc(number);
   *   text(commas, 15, 33);
   *
   *   // Display the number with four digits
   *   // to the left of the decimal.
   *   let decimals = nfc(number, 2);
   *   text(decimals, 15, 67);
   *
   *   describe(
   *     'The numbers "12,345" and "12,345.00" written on separate lines. The text is in black on a gray background.'
   *   );
   * }
   *
   * @example
   * function setup() {
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Create an array of numbers.
   *   let numbers = [12345, 6789];
   *
   *   // Convert the numbers to formatted strings.
   *   let formatted = nfc(numbers);
   *
   *   // Style the text.
   *   textAlign(CENTER, CENTER);
   *   textSize(14);
   *
   *   // Iterate over the array.
   *   for (let i = 0; i < formatted.length; i += 1) {
   *
   *     // Calculate the y-coordinate.
   *     let y = (i + 1) * 33;
   *
   *     // Display the original and formatted numbers.
   *     text(`${numbers[i]} : ${formatted[i]}`, 50, y);
   *   }
   *
   *   describe(
   *     'The text "12345 : 12,345" and "6789 : 6,789" written on two separate lines. The text is in black on a gray background.'
   *   );
   * }
   */
  /**
   * @method nfc
   * @param  {Number[]} nums numbers to format.
   * @param  {Integer|String} [right]
   * @return {String[]} formatted strings.
   */
  fn.nfc = function(num, right) {
    // p5._validateParameters('nfc', arguments);
    if (num instanceof Array) {
      return num.map(x => doNfc(x, right));
    } else {
      return doNfc(num, right);
    }
  };
  function doNfc(num, right) {
    num = num.toString();
    const dec = num.indexOf('.');
    let rem = dec !== -1 ? num.substring(dec) : '';
    let n = dec !== -1 ? num.substring(0, dec) : num;
    n = n.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ',');
    if (right === 0) {
      rem = '';
    } else if (typeof right !== 'undefined') {
      if (right > rem.length) {
        rem += dec === -1 ? '.' : '';
        const len = right - rem.length + 1;
        for (let i = 0; i < len; i++) {
          rem += '0';
        }
      } else {
        rem = rem.substring(0, right + 1);
      }
    }
    return n + rem;
  }

  /**
   * Converts a `Number` into a `String` with a plus or minus sign.
   *
   * `nfp()` converts numbers such as 123 into strings formatted with a `+` or
   * `-` symbol to mark whether they're positive or negative, as in `'+123'`.
   *
   * The first parameter, `num`, is the number to convert to a string. For
   * example, calling `nfp(123.45)` returns the string `'+123.45'`. If an array
   * of numbers is passed, as in `nfp([123.45, -6.78])`, an array of formatted
   * strings will be returned.
   *
   * The second parameter, `left`, is optional. If a number is passed, as in
   * `nfp(123.45, 4)`, it sets the minimum number of digits to include to the
   * left of the decimal place. If `left` is larger than the number of digits in
   * `num`, then unused digits will be set to 0. For example, calling
   * `nfp(123.45, 4)` returns the string `'+0123.45'`.
   *
   * The third parameter, `right`, is also optional. If a number is passed, as
   * in `nfp(123.45, 4, 1)`, it sets the minimum number of digits to include to
   * the right of the decimal place. If `right` is smaller than the number of
   * decimal places in `num`, then `num` will be rounded to the given number of
   * decimal places.  For example, calling `nfp(123.45, 4, 1)` returns the
   * string `'+0123.5'`. If `right` is larger than the number of decimal places
   * in `num`, then unused decimal places will be set to 0.  For example,
   * calling `nfp(123.45, 4, 3)` returns the string `'+0123.450'`.
   *
   * @method nfp
   * @param {Number} num number to format.
   * @param {Integer} [left] number of digits to include to the left of the
   *                         decimal point.
   * @param {Integer} [right] number of digits to include to the right of the
   *                          decimal point.
   * @return {String} formatted string.
   *
   * @example
   * function setup() {
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Create number variables.
   *   let positive = 123;
   *   let negative = -123;
   *
   *   // Convert the positive number to a formatted string.
   *   let p = nfp(positive);
   *
   *   // Convert the negative number to a formatted string
   *   // with four digits to the left of the decimal
   *   // and two digits to the right of the decimal.
   *   let n = nfp(negative, 4, 2);
   *
   *   // Style the text.
   *   textAlign(CENTER, CENTER);
   *   textSize(14);
   *
   *   // Display the original and formatted numbers.
   *   text(`${positive} : ${p}`, 50, 33);
   *   text(`${negative} : ${n}`, 50, 67);
   *
   *   describe(
   *     'The text "123 : +123" and "-123 : -123.00" written on separate lines. The text is in black on a gray background.'
   *   );
   * }
   *
   * @example
   * function setup() {
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Create number variables.
   *   let numbers = [123, -4.56];
   *
   *   // Convert the numbers to formatted strings
   *   // with four digits to the left of the decimal
   *   // and one digit to the right of the decimal.
   *   let formatted = nfp(numbers, 4, 1);
   *
   *   // Style the text.
   *   textAlign(CENTER, CENTER);
   *   textSize(14);
   *
   *   // Iterate over the array.
   *   for (let i = 0; i < formatted.length; i += 1) {
   *
   *     // Calculate the y-coordinate.
   *     let y = (i + 1) * 33;
   *
   *     // Display the original and formatted numbers.
   *     text(`${numbers[i]} : ${formatted[i]}`, 50, y);
   *   }
   *
   *   describe(
   *     'The text "123 : +0123.0" and "-4.56 : 00-4.6" written on separate lines. The text is in black on a gray background.'
   *   );
   * }
   */
  /**
   * @method nfp
   * @param {Number[]} nums numbers to format.
   * @param {Integer} [left]
   * @param {Integer} [right]
   * @return {String[]} formatted strings.
   */
  fn.nfp = function(...args) {
    // p5._validateParameters('nfp', args);
    const nfRes = fn.nf.apply(this, args);
    if (nfRes instanceof Array) {
      return nfRes.map(addNfp);
    } else {
      return addNfp(nfRes);
    }
  };

  function addNfp(num) {
    return parseFloat(num) > 0 ? `+${num.toString()}` : num.toString();
  }

  /**
   * Converts a positive `Number` into a `String` with an extra space in front.
   *
   * `nfs()` converts positive numbers such as 123.45 into strings formatted
   * with an extra space in front, as in ' 123.45'. Doing so can be helpful for
   * aligning positive and negative numbers.
   *
   * The first parameter, `num`, is the number to convert to a string. For
   * example, calling `nfs(123.45)` returns the string `' 123.45'`.
   *
   * The second parameter, `left`, is optional. If a number is passed, as in
   * `nfs(123.45, 4)`, it sets the minimum number of digits to include to the
   * left of the decimal place. If `left` is larger than the number of digits in
   * `num`, then unused digits will be set to 0. For example, calling
   * `nfs(123.45, 4)` returns the string `' 0123.45'`.
   *
   * The third parameter, `right`, is also optional. If a number is passed, as
   * in `nfs(123.45, 4, 1)`, it sets the minimum number of digits to include to
   * the right of the decimal place. If `right` is smaller than the number of
   * decimal places in `num`, then `num` will be rounded to the given number of
   * decimal places.  For example, calling `nfs(123.45, 4, 1)` returns the
   * string `' 0123.5'`. If `right` is larger than the number of decimal places
   * in `num`, then unused decimal places will be set to 0.  For example,
   * calling `nfs(123.45, 4, 3)` returns the string `' 0123.450'`.
   *
   * @method nfs
   * @param {Number} num number to format.
   * @param {Integer} [left] number of digits to include to the left of the
   *                         decimal point.
   * @param {Integer} [right] number of digits to include to the right of the
   *                          decimal point.
   * @return {String} formatted string.
   *
   * @example
   * function setup() {
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Create number variables.
   *   let positive = 123;
   *   let negative = -123;
   *
   *   // Convert the positive number to a formatted string.
   *   let formatted = nfs(positive);
   *
   *   // Style the text.
   *   textAlign(CENTER, CENTER);
   *   textFont('Courier New');
   *   textSize(16);
   *
   *   // Display the negative number and the formatted positive number.
   *   text(negative, 50, 33);
   *   text(formatted, 50, 67);
   *
   *   describe(
   *     'The numbers -123 and 123 written on separate lines. The numbers align vertically. The text is in black on a gray background.'
   *   );
   * }
   *
   * @example
   * function setup() {
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Create a number variable.
   *   let number = 123.45;
   *
   *   // Convert the positive number to a formatted string.
   *   // Use four digits to the left of the decimal and
   *   // one digit to the right.
   *   let formatted = nfs(number, 4, 1);
   *
   *   // Style the text.
   *   textAlign(CENTER, CENTER);
   *   textFont('Courier New');
   *   textSize(16);
   *
   *   // Display a negative version of the number and
   *   // the formatted positive version.
   *   text('-0123.5', 50, 33);
   *   text(formatted, 50, 67);
   *
   *   describe(
   *     'The numbers "-0123.5" and "0123.5" written on separate lines. The numbers align vertically. The text is in black on a gray background.'
   *   );
   * }
   */
  /**
   * @method nfs
   * @param {Array} nums numbers to format.
   * @param {Integer} [left]
   * @param {Integer} [right]
   * @return {String[]} formatted strings.
   */
  fn.nfs = function(...args) {
    // p5._validateParameters('nfs', args);
    const nfRes = fn.nf.apply(this, args);
    if (nfRes instanceof Array) {
      return nfRes.map(addNfs);
    } else {
      return addNfs(nfRes);
    }
  };

  function addNfs(num) {
    return parseFloat(num) >= 0 ? ` ${num.toString()}` : num.toString();
  }

  /**
   * Splits a `String` into pieces and returns an array containing the pieces.
   *
   * `splitTokens()` is an enhanced version of
   * <a href="#/p5/split">split()</a>. It can split a string when any characters
   * from a list are detected.
   *
   * The first parameter, `value`, is the string to split.
   *
   * The second parameter, `delim`, is optional. It sets the character(s) that
   * should be used to split the string. `delim` can be a single string, as in
   * `splitTokens('rock...paper...scissors...shoot', '...')`, or an array of
   * strings, as in
   * `splitTokens('rock;paper,scissors...shoot, [';', ',', '...'])`. By default,
   * if no `delim` characters are specified, then any whitespace character is
   * used to split. Whitespace characters include tab (`\t`), line feed (`\n`),
   * carriage return (`\r`), form feed (`\f`), and space.
   *
   * @method splitTokens
   * @deprecated This will be removed in a future version of p5.js to make way for a new, friendlier version :)
   * @param  {String} value string to split.
   * @param  {String} [delim] character(s) to use for splitting the string.
   * @return {String[]} separated strings.
   *
   * @example
   * function setup() {
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Create a string variable.
   *   let string = 'rock paper scissors shoot';
   *
   *   // Split the string at each space.
   *   let words = splitTokens(string);
   *
   *   // Print the array to the console.
   *   print(words);
   *
   *   // Style the text.
   *   textAlign(CENTER, CENTER);
   *   textFont('Courier New');
   *   textSize(12);
   *
   *   // Iterate over the words array.
   *   for (let i = 0; i < words.length; i += 1) {
   *
   *     // Calculate the y-coordinate.
   *     let y = (i + 1) * 20;
   *
   *     // Display the word.
   *     text(words[i], 50, y);
   *   }
   *
   *   describe(
   *     'The words "rock", "paper", "scissors", and "shoot" written on separate lines. The text is black on a gray background.'
   *   );
   * }
   *
   * @example
   * function setup() {
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Create a string variable.
   *   let string = 'rock...paper...scissors...shoot';
   *
   *   // Split the string at each ...
   *   let words = splitTokens(string, '...');
   *
   *   // Print the array to the console.
   *   print(words);
   *
   *   // Style the text.
   *   textAlign(CENTER, CENTER);
   *   textFont('Courier New');
   *   textSize(12);
   *
   *   // Iterate over the words array.
   *   for (let i = 0; i < words.length; i += 1) {
   *
   *     // Calculate the y-coordinate.
   *     let y = (i + 1) * 20;
   *
   *     // Display the word.
   *     text(words[i], 50, y);
   *   }
   *
   *   describe(
   *     'The words "rock", "paper", "scissors", and "shoot" written on separate lines. The text is black on a gray background.'
   *   );
   * }
   *
   * @example
   * function setup() {
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Create a string variable.
   *   let string = 'rock;paper,scissors...shoot';
   *
   *   // Split the string at each semicolon, comma, or ...
   *   let words = splitTokens(string, [';', ',', '...']);
   *
   *   // Print the array to the console.
   *   print(words);
   *
   *   // Style the text.
   *   textAlign(CENTER, CENTER);
   *   textFont('Courier New');
   *   textSize(12);
   *
   *   // Iterate over the words array.
   *   for (let i = 0; i < words.length; i += 1) {
   *
   *     // Calculate the y-coordinate.
   *     let y = (i + 1) * 20;
   *
   *     // Display the word.
   *     text(words[i], 50, y);
   *   }
   *
   *   describe(
   *     'The words "rock", "paper", "scissors", and "shoot" written on separate lines. The text is black on a gray background.'
   *   );
   * }
   */
  fn.splitTokens = function(value, delims) {
    // p5._validateParameters('splitTokens', arguments);
    let d;
    if (typeof delims !== 'undefined') {
      let str = delims;
      const sqc = /\]/g.exec(str);
      let sqo = /\[/g.exec(str);
      if (sqo && sqc) {
        str = str.slice(0, sqc.index) + str.slice(sqc.index + 1);
        sqo = /\[/g.exec(str);
        str = str.slice(0, sqo.index) + str.slice(sqo.index + 1);
        d = new RegExp(`[\\[${str}\\]]`, 'g');
      } else if (sqc) {
        str = str.slice(0, sqc.index) + str.slice(sqc.index + 1);
        d = new RegExp(`[${str}\\]]`, 'g');
      } else if (sqo) {
        str = str.slice(0, sqo.index) + str.slice(sqo.index + 1);
        d = new RegExp(`[${str}\\[]`, 'g');
      } else {
        d = new RegExp(`[${str}]`, 'g');
      }
    } else {
      d = /\s/g;
    }
    return value.split(d).filter(n => n);
  };

  /**
   * Shuffles the elements of an array.
   *
   * The first parameter, `array`, is the array to be shuffled. For example,
   * calling `shuffle(myArray)` will shuffle the elements of `myArray`. By
   * default, the original array won’t be modified. Instead, a copy will be
   * created, shuffled, and returned.
   *
   * The second parameter, `modify`, is optional. If `true` is passed, as in
   * `shuffle(myArray, true)`, then the array will be shuffled in place without
   * making a copy.
   *
   * @method shuffle
   * @param  {Array} array array to shuffle.
   * @param  {Boolean} [modify] if `true`, shuffle the original array in place. Defaults to `false`.
   * @return {Array} shuffled array.
   *
   * @example
   * function setup() {
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Create an array of colors.
   *   let colors = ['red', 'orange', 'yellow', 'green', 'blue', 'indigo', 'violet'];
   *
   *   // Create a shuffled copy of the array.
   *   let shuffledColors = shuffle(colors);
   *
   *   // Draw  a row of circles using the original array.
   *   for (let i = 0; i < colors.length; i += 1) {
   *     // Calculate the x-coordinate.
   *     let x = (i + 1) * 12.5;
   *
   *     // Style the circle.
   *     let c = colors[i];
   *     fill(c);
   *
   *     // Draw the circle.
   *     circle(x, 33, 10);
   *   }
   *
   *   // Draw  a row of circles using the original array.
   *   for (let i = 0; i < shuffledColors.length; i += 1) {
   *     // Calculate the x-coordinate.
   *     let x = (i + 1) * 12.5;
   *
   *     // Style the circle.
   *     let c = shuffledColors[i];
   *     fill(c);
   *
   *     // Draw the circle.
   *     circle(x, 67, 10);
   *   }
   *
   *   describe(
   *     'Two rows of circles on a gray background. The top row follows the color sequence ROYGBIV. The bottom row has all the same colors but they are shuffled.'
   *   );
   * }
   *
   * @example
   * function setup() {
   *   createCanvas(100, 100);
   *
   *   background(200);
   *
   *   // Create an array of colors.
   *   let colors = ['red', 'orange', 'yellow', 'green', 'blue', 'indigo', 'violet'];
   *
   *   // Shuffle the array.
   *   shuffle(colors, true);
   *
   *   // Draw  a row of circles using the original array.
   *   for (let i = 0; i < colors.length; i += 1) {
   *     // Calculate the x-coordinate.
   *     let x = (i + 1) * 12.5;
   *
   *     // Style the circle.
   *     let c = colors[i];
   *     fill(c);
   *
   *     // Draw the circle.
   *     circle(x, 50, 10);
   *   }
   *
   *   describe(
   *     'A row of colorful circles on a gray background. Their sequence changes each time the sketch runs.'
   *   );
   * }
   */
  fn.shuffle = function (arr, modify) {
    const isView = ArrayBuffer && ArrayBuffer.isView && ArrayBuffer.isView(arr);
    arr = modify || isView ? arr : arr.slice();

    let rnd,
      tmp,
      idx = arr.length;
    while (idx > 1) {
      rnd = (this.random(0, 1) * idx) | 0;

      tmp = arr[--idx];
      arr[idx] = arr[rnd];
      arr[rnd] = tmp;
    }

    return arr;
  };
}

if(typeof p5 !== 'undefined'){
  utilityFunctions(p5, p5.prototype);
}

export { utilityFunctions as default };
