var H5P = H5P || {};

/**
 * Class responsible for creating a circular progress bar
 */

H5P.JoubelProgressCircle = (function ($) {

  /**
   * Constructor for the Progress Circle
   *
   * @param {Number} number The amount of progress to display
   * @param {string} progressColor Color for the progress meter
   * @param {string} backgroundColor Color behind the progress meter
   */
  function ProgressCircle(number, progressColor, fillColor, backgroundColor) {
    progressColor = progressColor || '#1a73d9';
    fillColor = fillColor || '#f0f0f0';
    backgroundColor = backgroundColor || '#ffffff';
    var progressColorRGB = this.hexToRgb(progressColor);

    //Verify number
    try {
      number = Number(number);
      if (number === '') {
        throw 'is empty';
      }
      if (isNaN(number)) {
        throw 'is not a number';
      }
    } catch (e) {
      number = 'err';
    }

    //Draw circle
    if (number > 100) {
      number = 100;
    }

    // We can not use rgba, since they will stack on top of each other.
    // Instead we create the equivalent of the rgba color
    // and applies this to the activeborder and background color.
    var progressColorString = 'rgb(' + parseInt(progressColorRGB.r, 10) +
      ',' + parseInt(progressColorRGB.g, 10) +
      ',' + parseInt(progressColorRGB.b, 10) + ')';

    // Circle wrapper
    var $wrapper = $('<div/>', {
      'class': "joubel-progress-circle-wrapper"
    });

    //Active border indicates progress
    var $activeBorder = $('<div/>', {
      'class': "joubel-progress-circle-active-border"
    }).appendTo($wrapper);

    //Background circle
    var $backgroundCircle = $('<div/>', {
      'class': "joubel-progress-circle-circle"
    }).appendTo($activeBorder);

    //Progress text/number
    $('<span/>', {
      'text': number + '%',
      'class': "joubel-progress-circle-percentage"
    }).appendTo($backgroundCircle);

    var deg = number * 3.6;
    if (deg <= 180) {
      $activeBorder.css('background-image',
        'linear-gradient(' + (90 + deg) + 'deg, transparent 50%, ' + fillColor + ' 50%),' +
        'linear-gradient(90deg, ' + fillColor + ' 50%, transparent 50%)')
        .css('border', '2px solid' + backgroundColor)
        .css('background-color', progressColorString);
    } else {
      $activeBorder.css('background-image',
        'linear-gradient(' + (deg - 90) + 'deg, transparent 50%, ' + progressColorString + ' 50%),' +
        'linear-gradient(90deg, ' + fillColor + ' 50%, transparent 50%)')
        .css('border', '2px solid' + backgroundColor)
        .css('background-color', progressColorString);
    }

    this.$activeBorder = $activeBorder;
    this.$backgroundCircle = $backgroundCircle;
    this.$wrapper = $wrapper;

    this.initResizeFunctionality();

    return $wrapper;
  }

  /**
   * Initializes resize functionality for the progress circle
   */
  ProgressCircle.prototype.initResizeFunctionality = function () {
    var self = this;

    $(window).resize(function () {
      // Queue resize
      setTimeout(function () {
        self.resize();
      });
    });

    // First resize
    setTimeout(function () {
      self.resize();
    }, 0);
  };

  /**
   * Resize function makes progress circle grow or shrink relative to parent container
   */
  ProgressCircle.prototype.resize = function () {
    var $parent = this.$wrapper.parent();

    if ($parent !== undefined && $parent) {

      // Measurements
      var fontSize = parseInt($parent.css('font-size'), 10);

      // Static sizes
      var fontSizeMultiplum = 3.75;
      var progressCircleWidthPx = parseInt((fontSize / 4.5), 10) % 2 === 0 ? parseInt((fontSize / 4.5), 10) + 4 : parseInt((fontSize / 4.5), 10) + 5;
      var progressCircleOffset = progressCircleWidthPx / 2;

      var width = fontSize * fontSizeMultiplum;
      var height = fontSize * fontSizeMultiplum;
      this.$activeBorder.css({
        'width': width,
        'height': height
      });

      this.$backgroundCircle.css({
        'width': width - progressCircleWidthPx,
        'height': height - progressCircleWidthPx,
        'top': progressCircleOffset,
        'left': progressCircleOffset
      });
    }
  };

  /**
   * Hex to RGB conversion
   * @param hex
   * @returns {{r: Number, g: Number, b: Number}}
   */
  ProgressCircle.prototype.hexToRgb = function (hex) {
    var result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex);
    return result ? {
      r: parseInt(result[1], 16),
      g: parseInt(result[2], 16),
      b: parseInt(result[3], 16)
    } : null;
  };

  return ProgressCircle;

}(H5P.jQuery));