‘use strict’;

!function($) {

/**

* Slider module.
* @module foundation.slider
* @requires foundation.util.motion
* @requires foundation.util.triggers
* @requires foundation.util.keyboard
* @requires foundation.util.touch
*/

class Slider {

/**
 * Creates a new instance of a slider control.
 * @class
 * @param {jQuery} element - jQuery object to make into a slider control.
 * @param {Object} options - Overrides to the default plugin settings.
 */
constructor(element, options) {
  this.$element = element;
  this.options = $.extend({}, Slider.defaults, this.$element.data(), options);

  this._init();

  Foundation.registerPlugin(this, 'Slider');
  Foundation.Keyboard.register('Slider', {
    'ltr': {
      'ARROW_RIGHT': 'increase',
      'ARROW_UP': 'increase',
      'ARROW_DOWN': 'decrease',
      'ARROW_LEFT': 'decrease',
      'SHIFT_ARROW_RIGHT': 'increase_fast',
      'SHIFT_ARROW_UP': 'increase_fast',
      'SHIFT_ARROW_DOWN': 'decrease_fast',
      'SHIFT_ARROW_LEFT': 'decrease_fast'
    },
    'rtl': {
      'ARROW_LEFT': 'increase',
      'ARROW_RIGHT': 'decrease',
      'SHIFT_ARROW_LEFT': 'increase_fast',
      'SHIFT_ARROW_RIGHT': 'decrease_fast'
    }
  });
}

/**
 * Initilizes the plugin by reading/setting attributes, creating collections and setting the initial position of the handle(s).
 * @function
 * @private
 */
_init() {
  this.inputs = this.$element.find('input');
  this.handles = this.$element.find('[data-slider-handle]');

  this.$handle = this.handles.eq(0);
  this.$input = this.inputs.length ? this.inputs.eq(0) : $(`#${this.$handle.attr('aria-controls')}`);
  this.$fill = this.$element.find('[data-slider-fill]').css(this.options.vertical ? 'height' : 'width', 0);

  var isDbl = false,
      _this = this;
  if (this.options.disabled || this.$element.hasClass(this.options.disabledClass)) {
    this.options.disabled = true;
    this.$element.addClass(this.options.disabledClass);
  }
  if (!this.inputs.length) {
    this.inputs = $().add(this.$input);
    this.options.binding = true;
  }

  this._setInitAttr(0);

  if (this.handles[1]) {
    this.options.doubleSided = true;
    this.$handle2 = this.handles.eq(1);
    this.$input2 = this.inputs.length > 1 ? this.inputs.eq(1) : $(`#${this.$handle2.attr('aria-controls')}`);

    if (!this.inputs[1]) {
      this.inputs = this.inputs.add(this.$input2);
    }
    isDbl = true;

    // this.$handle.triggerHandler('click.zf.slider');
    this._setInitAttr(1);
  }

  // Set handle positions
  this.setHandles();

  this._events();
}

setHandles() {
  if(this.handles[1]) {
    this._setHandlePos(this.$handle, this.inputs.eq(0).val(), true, () => {
      this._setHandlePos(this.$handle2, this.inputs.eq(1).val(), true);
    });
  } else {
    this._setHandlePos(this.$handle, this.inputs.eq(0).val(), true);
  }
}

_reflow() {
  this.setHandles();
}
/**
* @function
* @private
* @param {Number} value - floating point (the value) to be transformed using to a relative position on the slider (the inverse of _value)
*/
_pctOfBar(value) {
  var pctOfBar = percent(value - this.options.start, this.options.end - this.options.start)

  switch(this.options.positionValueFunction) {
  case "pow":
    pctOfBar = this._logTransform(pctOfBar);
    break;
  case "log":
    pctOfBar = this._powTransform(pctOfBar);
    break;
  }

  return pctOfBar.toFixed(2)
}

/**
* @function
* @private
* @param {Number} pctOfBar - floating point, the relative position of the slider (typically between 0-1) to be transformed to a value
*/
_value(pctOfBar) {
  switch(this.options.positionValueFunction) {
  case "pow":
    pctOfBar = this._powTransform(pctOfBar);
    break;
  case "log":
    pctOfBar = this._logTransform(pctOfBar);
    break;
  }
  var value = (this.options.end - this.options.start) * pctOfBar + this.options.start;

  return value
}

/**
* @function
* @private
* @param {Number} value - floating point (typically between 0-1) to be transformed using the log function
*/
_logTransform(value) {
  return baseLog(this.options.nonLinearBase, ((value*(this.options.nonLinearBase-1))+1))
}

/**
* @function
* @private
* @param {Number} value - floating point (typically between 0-1) to be transformed using the power function
*/
_powTransform(value) {
  return (Math.pow(this.options.nonLinearBase, value) - 1) / (this.options.nonLinearBase - 1)
}

/**
 * Sets the position of the selected handle and fill bar.
 * @function
 * @private
 * @param {jQuery} $hndl - the selected handle to move.
 * @param {Number} location - floating point between the start and end values of the slider bar.
 * @param {Function} cb - callback function to fire on completion.
 * @fires Slider#moved
 * @fires Slider#changed
 */
_setHandlePos($hndl, location, noInvert, cb) {
  // don't move if the slider has been disabled since its initialization
  if (this.$element.hasClass(this.options.disabledClass)) {
    return;
  }
  //might need to alter that slightly for bars that will have odd number selections.
  location = parseFloat(location);//on input change events, convert string to number...grumble.

  // prevent slider from running out of bounds, if value exceeds the limits set through options, override the value to min/max
  if (location < this.options.start) { location = this.options.start; }
  else if (location > this.options.end) { location = this.options.end; }

  var isDbl = this.options.doubleSided;

  if (isDbl) { //this block is to prevent 2 handles from crossing eachother. Could/should be improved.
    if (this.handles.index($hndl) === 0) {
      var h2Val = parseFloat(this.$handle2.attr('aria-valuenow'));
      location = location >= h2Val ? h2Val - this.options.step : location;
    } else {
      var h1Val = parseFloat(this.$handle.attr('aria-valuenow'));
      location = location <= h1Val ? h1Val + this.options.step : location;
    }
  }

  //this is for single-handled vertical sliders, it adjusts the value to account for the slider being "upside-down"
  //for click and drag events, it's weird due to the scale(-1, 1) css property
  if (this.options.vertical && !noInvert) {
    location = this.options.end - location;
  }

  var _this = this,
      vert = this.options.vertical,
      hOrW = vert ? 'height' : 'width',
      lOrT = vert ? 'top' : 'left',
      handleDim = $hndl[0].getBoundingClientRect()[hOrW],
      elemDim = this.$element[0].getBoundingClientRect()[hOrW],
      //percentage of bar min/max value based on click or drag point
      pctOfBar = this._pctOfBar(location),
      //number of actual pixels to shift the handle, based on the percentage obtained above
      pxToMove = (elemDim - handleDim) * pctOfBar,
      //percentage of bar to shift the handle
      movement = (percent(pxToMove, elemDim) * 100).toFixed(this.options.decimal);
      //fixing the decimal value for the location number, is passed to other methods as a fixed floating-point value
      location = parseFloat(location.toFixed(this.options.decimal));
      // declare empty object for css adjustments, only used with 2 handled-sliders
  var css = {};

  this._setValues($hndl, location);

  // TODO update to calculate based on values set to respective inputs??
  if (isDbl) {
    var isLeftHndl = this.handles.index($hndl) === 0,
        //empty variable, will be used for min-height/width for fill bar
        dim,
        //percentage w/h of the handle compared to the slider bar
        handlePct =  ~~(percent(handleDim, elemDim) * 100);
    //if left handle, the math is slightly different than if it's the right handle, and the left/top property needs to be changed for the fill bar
    if (isLeftHndl) {
      //left or top percentage value to apply to the fill bar.
      css[lOrT] = `${movement}%`;
      //calculate the new min-height/width for the fill bar.
      dim = parseFloat(this.$handle2[0].style[lOrT]) - movement + handlePct;
      //this callback is necessary to prevent errors and allow the proper placement and initialization of a 2-handled slider
      //plus, it means we don't care if 'dim' isNaN on init, it won't be in the future.
      if (cb && typeof cb === 'function') { cb(); }//this is only needed for the initialization of 2 handled sliders
    } else {
      //just caching the value of the left/bottom handle's left/top property
      var handlePos = parseFloat(this.$handle[0].style[lOrT]);
      //calculate the new min-height/width for the fill bar. Use isNaN to prevent false positives for numbers <= 0
      //based on the percentage of movement of the handle being manipulated, less the opposing handle's left/top position, plus the percentage w/h of the handle itself
      dim = movement - (isNaN(handlePos) ? (this.options.initialStart - this.options.start)/((this.options.end-this.options.start)/100) : handlePos) + handlePct;
    }
    // assign the min-height/width to our css object
    css[`min-${hOrW}`] = `${dim}%`;
  }

  this.$element.one('finished.zf.animate', function() {
                  /**
                   * Fires when the handle is done moving.
                   * @event Slider#moved
                   */
                  _this.$element.trigger('moved.zf.slider', [$hndl]);
              });

  //because we don't know exactly how the handle will be moved, check the amount of time it should take to move.
  var moveTime = this.$element.data('dragging') ? 1000/60 : this.options.moveTime;

  Foundation.Move(moveTime, $hndl, function() {
    // adjusting the left/top property of the handle, based on the percentage calculated above
    // if movement isNaN, that is because the slider is hidden and we cannot determine handle width,
    // fall back to next best guess.
    if (isNaN(movement)) {
      $hndl.css(lOrT, `${pctOfBar * 100}%`);
    }
    else {
      $hndl.css(lOrT, `${movement}%`);
    }

    if (!_this.options.doubleSided) {
      //if single-handled, a simple method to expand the fill bar
      _this.$fill.css(hOrW, `${pctOfBar * 100}%`);
    } else {
      //otherwise, use the css object we created above
      _this.$fill.css(css);
    }
  });

  /**
   * Fires when the value has not been change for a given time.
   * @event Slider#changed
   */
  clearTimeout(_this.timeout);
  _this.timeout = setTimeout(function(){
    _this.$element.trigger('changed.zf.slider', [$hndl]);
  }, _this.options.changedDelay);
}

/**
 * Sets the initial attribute for the slider element.
 * @function
 * @private
 * @param {Number} idx - index of the current handle/input to use.
 */
_setInitAttr(idx) {
  var initVal = (idx === 0 ? this.options.initialStart : this.options.initialEnd)
  var id = this.inputs.eq(idx).attr('id') || Foundation.GetYoDigits(6, 'slider');
  this.inputs.eq(idx).attr({
    'id': id,
    'max': this.options.end,
    'min': this.options.start,
    'step': this.options.step
  });
  this.inputs.eq(idx).val(initVal);
  this.handles.eq(idx).attr({
    'role': 'slider',
    'aria-controls': id,
    'aria-valuemax': this.options.end,
    'aria-valuemin': this.options.start,
    'aria-valuenow': initVal,
    'aria-orientation': this.options.vertical ? 'vertical' : 'horizontal',
    'tabindex': 0
  });
}

/**
 * Sets the input and `aria-valuenow` values for the slider element.
 * @function
 * @private
 * @param {jQuery} $handle - the currently selected handle.
 * @param {Number} val - floating point of the new value.
 */
_setValues($handle, val) {
  var idx = this.options.doubleSided ? this.handles.index($handle) : 0;
  this.inputs.eq(idx).val(val);
  $handle.attr('aria-valuenow', val);
}

/**
 * Handles events on the slider element.
 * Calculates the new location of the current handle.
 * If there are two handles and the bar was clicked, it determines which handle to move.
 * @function
 * @private
 * @param {Object} e - the `event` object passed from the listener.
 * @param {jQuery} $handle - the current handle to calculate for, if selected.
 * @param {Number} val - floating point number for the new value of the slider.
 * TODO clean this up, there's a lot of repeated code between this and the _setHandlePos fn.
 */
_handleEvent(e, $handle, val) {
  var value, hasVal;
  if (!val) {//click or drag events
    e.preventDefault();
    var _this = this,
        vertical = this.options.vertical,
        param = vertical ? 'height' : 'width',
        direction = vertical ? 'top' : 'left',
        eventOffset = vertical ? e.pageY : e.pageX,
        halfOfHandle = this.$handle[0].getBoundingClientRect()[param] / 2,
        barDim = this.$element[0].getBoundingClientRect()[param],
        windowScroll = vertical ? $(window).scrollTop() : $(window).scrollLeft();

    var elemOffset = this.$element.offset()[direction];

    // touch events emulated by the touch util give position relative to screen, add window.scroll to event coordinates...
    // best way to guess this is simulated is if clientY == pageY
    if (e.clientY === e.pageY) { eventOffset = eventOffset + windowScroll; }
    var eventFromBar = eventOffset - elemOffset;
    var barXY;
    if (eventFromBar < 0) {
      barXY = 0;
    } else if (eventFromBar > barDim) {
      barXY = barDim;
    } else {
      barXY = eventFromBar;
    }
    var offsetPct = percent(barXY, barDim);

    value = this._value(offsetPct);

    // turn everything around for RTL, yay math!
    if (Foundation.rtl() && !this.options.vertical) {value = this.options.end - value;}

    value = _this._adjustValue(null, value);
    //boolean flag for the setHandlePos fn, specifically for vertical sliders
    hasVal = false;

    if (!$handle) {//figure out which handle it is, pass it to the next function.
      var firstHndlPos = absPosition(this.$handle, direction, barXY, param),
          secndHndlPos = absPosition(this.$handle2, direction, barXY, param);
          $handle = firstHndlPos <= secndHndlPos ? this.$handle : this.$handle2;
    }

  } else {//change event on input
    value = this._adjustValue(null, val);
    hasVal = true;
  }

  this._setHandlePos($handle, value, hasVal);
}

/**
 * Adjustes value for handle in regard to step value. returns adjusted value
 * @function
 * @private
 * @param {jQuery} $handle - the selected handle.
 * @param {Number} value - value to adjust. used if $handle is falsy
 */
_adjustValue($handle, value) {
  var val,
    step = this.options.step,
    div = parseFloat(step/2),
    left, prev_val, next_val;
  if (!!$handle) {
    val = parseFloat($handle.attr('aria-valuenow'));
  }
  else {
    val = value;
  }
  left = val % step;
  prev_val = val - left;
  next_val = prev_val + step;
  if (left === 0) {
    return val;
  }
  val = val >= prev_val + div ? next_val : prev_val;
  return val;
}

/**
 * Adds event listeners to the slider elements.
 * @function
 * @private
 */
_events() {
  this._eventsForHandle(this.$handle);
  if(this.handles[1]) {
    this._eventsForHandle(this.$handle2);
  }
}

/**
 * Adds event listeners a particular handle
 * @function
 * @private
 * @param {jQuery} $handle - the current handle to apply listeners to.
 */
_eventsForHandle($handle) {
  var _this = this,
      curHandle,
      timer;

    this.inputs.off('change.zf.slider').on('change.zf.slider', function(e) {
      var idx = _this.inputs.index($(this));
      _this._handleEvent(e, _this.handles.eq(idx), $(this).val());
    });

    if (this.options.clickSelect) {
      this.$element.off('click.zf.slider').on('click.zf.slider', function(e) {
        if (_this.$element.data('dragging')) { return false; }

        if (!$(e.target).is('[data-slider-handle]')) {
          if (_this.options.doubleSided) {
            _this._handleEvent(e);
          } else {
            _this._handleEvent(e, _this.$handle);
          }
        }
      });
    }

  if (this.options.draggable) {
    this.handles.addTouch();

    var $body = $('body');
    $handle
      .off('mousedown.zf.slider')
      .on('mousedown.zf.slider', function(e) {
        $handle.addClass('is-dragging');
        _this.$fill.addClass('is-dragging');//
        _this.$element.data('dragging', true);

        curHandle = $(e.currentTarget);

        $body.on('mousemove.zf.slider', function(e) {
          e.preventDefault();
          _this._handleEvent(e, curHandle);

        }).on('mouseup.zf.slider', function(e) {
          _this._handleEvent(e, curHandle);

          $handle.removeClass('is-dragging');
          _this.$fill.removeClass('is-dragging');
          _this.$element.data('dragging', false);

          $body.off('mousemove.zf.slider mouseup.zf.slider');
        });
    })
    // prevent events triggered by touch
    .on('selectstart.zf.slider touchmove.zf.slider', function(e) {
      e.preventDefault();
    });
  }

  $handle.off('keydown.zf.slider').on('keydown.zf.slider', function(e) {
    var _$handle = $(this),
        idx = _this.options.doubleSided ? _this.handles.index(_$handle) : 0,
        oldValue = parseFloat(_this.inputs.eq(idx).val()),
        newValue;

    // handle keyboard event with keyboard util
    Foundation.Keyboard.handleKey(e, 'Slider', {
      decrease: function() {
        newValue = oldValue - _this.options.step;
      },
      increase: function() {
        newValue = oldValue + _this.options.step;
      },
      decrease_fast: function() {
        newValue = oldValue - _this.options.step * 10;
      },
      increase_fast: function() {
        newValue = oldValue + _this.options.step * 10;
      },
      handled: function() { // only set handle pos when event was handled specially
        e.preventDefault();
        _this._setHandlePos(_$handle, newValue, true);
      }
    });
    /*if (newValue) { // if pressed key has special function, update value
      e.preventDefault();
      _this._setHandlePos(_$handle, newValue);
    }*/
  });
}

/**
 * Destroys the slider plugin.
 */
destroy() {
  this.handles.off('.zf.slider');
  this.inputs.off('.zf.slider');
  this.$element.off('.zf.slider');

  clearTimeout(this.timeout);

  Foundation.unregisterPlugin(this);
}

}

Slider.defaults = {

/**
 * Minimum value for the slider scale.
 * @option
 * @type {number}
 * @default 0
 */
start: 0,
/**
 * Maximum value for the slider scale.
 * @option
 * @type {number}
 * @default 100
 */
end: 100,
/**
 * Minimum value change per change event.
 * @option
 * @type {number}
 * @default 1
 */
step: 1,
/**
 * Value at which the handle/input *(left handle/first input)* should be set to on initialization.
 * @option
 * @type {number}
 * @default 0
 */
initialStart: 0,
/**
 * Value at which the right handle/second input should be set to on initialization.
 * @option
 * @type {number}
 * @default 100
 */
initialEnd: 100,
/**
 * Allows the input to be located outside the container and visible. Set to by the JS
 * @option
 * @type {boolean}
 * @default false
 */
binding: false,
/**
 * Allows the user to click/tap on the slider bar to select a value.
 * @option
 * @type {boolean}
 * @default true
 */
clickSelect: true,
/**
 * Set to true and use the `vertical` class to change alignment to vertical.
 * @option
 * @type {boolean}
 * @default false
 */
vertical: false,
/**
 * Allows the user to drag the slider handle(s) to select a value.
 * @option
 * @type {boolean}
 * @default true
 */
draggable: true,
/**
 * Disables the slider and prevents event listeners from being applied. Double checked by JS with `disabledClass`.
 * @option
 * @type {boolean}
 * @default false
 */
disabled: false,
/**
 * Allows the use of two handles. Double checked by the JS. Changes some logic handling.
 * @option
 * @type {boolean}
 * @default false
 */
doubleSided: false,
/**
 * Potential future feature.
 */
// steps: 100,
/**
 * Number of decimal places the plugin should go to for floating point precision.
 * @option
 * @type {number}
 * @default 2
 */
decimal: 2,
/**
 * Time delay for dragged elements.
 */
// dragDelay: 0,
/**
 * Time, in ms, to animate the movement of a slider handle if user clicks/taps on the bar. Needs to be manually set if updating the transition time in the Sass settings.
 * @option
 * @type {number}
 * @default 200
 */
moveTime: 200,//update this if changing the transition time in the sass
/**
 * Class applied to disabled sliders.
 * @option
 * @type {string}
 * @default 'disabled'
 */
disabledClass: 'disabled',
/**
 * Will invert the default layout for a vertical<span data-tooltip title="who would do this???"> </span>slider.
 * @option
 * @type {boolean}
 * @default false
 */
invertVertical: false,
/**
 * Milliseconds before the `changed.zf-slider` event is triggered after value change.
 * @option
 * @type {number}
 * @default 500
 */
changedDelay: 500,
/**
* Basevalue for non-linear sliders
* @option
* @type {number}
* @default 5
*/
nonLinearBase: 5,
/**
* Basevalue for non-linear sliders, possible values are: `'linear'`, `'pow'` & `'log'`. Pow and Log use the nonLinearBase setting.
* @option
* @type {string}
* @default 'linear'
*/
positionValueFunction: 'linear',

};

function percent(frac, num) {

return (frac / num);

} function absPosition($handle, dir, clickPos, param) {

return Math.abs(($handle.position()[dir] + ($handle[param]() / 2)) - clickPos);

} function baseLog(base, value) {

return Math.log(value)/Math.log(base)

}

// Window exports Foundation.plugin(Slider, ‘Slider’);

}(jQuery);