'use strict';

!function ($) {

  Foundation.Box = {
    ImNotTouchingYou: ImNotTouchingYou,
    GetDimensions: GetDimensions,
    GetOffsets: GetOffsets
  };

  /**
   * Compares the dimensions of an element to a container and determines collision events with container.
   * @function
   * @param {jQuery} element - jQuery object to test for collisions.
   * @param {jQuery} parent - jQuery object to use as bounding container.
   * @param {Boolean} lrOnly - set to true to check left and right values only.
   * @param {Boolean} tbOnly - set to true to check top and bottom values only.
   * @default if no parent object passed, detects collisions with `window`.
   * @returns {Boolean} - true if collision free, false if a collision in any direction.
   */
  function ImNotTouchingYou(element, parent, lrOnly, tbOnly) {
    var eleDims = GetDimensions(element),
        top,
        bottom,
        left,
        right;

    if (parent) {
      var parDims = GetDimensions(parent);

      bottom = eleDims.offset.top + eleDims.height <= parDims.height + parDims.offset.top;
      top = eleDims.offset.top >= parDims.offset.top;
      left = eleDims.offset.left >= parDims.offset.left;
      right = eleDims.offset.left + eleDims.width <= parDims.width + parDims.offset.left;
    } else {
      bottom = eleDims.offset.top + eleDims.height <= eleDims.windowDims.height + eleDims.windowDims.offset.top;
      top = eleDims.offset.top >= eleDims.windowDims.offset.top;
      left = eleDims.offset.left >= eleDims.windowDims.offset.left;
      right = eleDims.offset.left + eleDims.width <= eleDims.windowDims.width;
    }

    var allDirs = [bottom, top, left, right];

    if (lrOnly) {
      return left === right === true;
    }

    if (tbOnly) {
      return top === bottom === true;
    }

    return allDirs.indexOf(false) === -1;
  };

  /**
   * Uses native methods to return an object of dimension values.
   * @function
   * @param {jQuery || HTML} element - jQuery object or DOM element for which to get the dimensions. Can be any element other that document or window.
   * @returns {Object} - nested object of integer pixel values
   * TODO - if element is window, return only those values.
   */
  function GetDimensions(elem, test) {
    elem = elem.length ? elem[0] : elem;

    if (elem === window || elem === document) {
      throw new Error("I'm sorry, Dave. I'm afraid I can't do that.");
    }

    var rect = elem.getBoundingClientRect(),
        parRect = elem.parentNode.getBoundingClientRect(),
        winRect = document.body.getBoundingClientRect(),
        winY = window.pageYOffset,
        winX = window.pageXOffset;

    return {
      width: rect.width,
      height: rect.height,
      offset: {
        top: rect.top + winY,
        left: rect.left + winX
      },
      parentDims: {
        width: parRect.width,
        height: parRect.height,
        offset: {
          top: parRect.top + winY,
          left: parRect.left + winX
        }
      },
      windowDims: {
        width: winRect.width,
        height: winRect.height,
        offset: {
          top: winY,
          left: winX
        }
      }
    };
  }

  /**
   * Returns an object of top and left integer pixel values for dynamically rendered elements,
   * such as: Tooltip, Reveal, and Dropdown
   * @function
   * @param {jQuery} element - jQuery object for the element being positioned.
   * @param {jQuery} anchor - jQuery object for the element's anchor point.
   * @param {String} position - a string relating to the desired position of the element, relative to it's anchor
   * @param {Number} vOffset - integer pixel value of desired vertical separation between anchor and element.
   * @param {Number} hOffset - integer pixel value of desired horizontal separation between anchor and element.
   * @param {Boolean} isOverflow - if a collision event is detected, sets to true to default the element to full width - any desired offset.
   * TODO alter/rewrite to work with `em` values as well/instead of pixels
   */
  function GetOffsets(element, anchor, position, vOffset, hOffset, isOverflow) {
    var $eleDims = GetDimensions(element),
        $anchorDims = anchor ? GetDimensions(anchor) : null;

    switch (position) {
      case 'top':
        return {
          left: Foundation.rtl() ? $anchorDims.offset.left - $eleDims.width + $anchorDims.width : $anchorDims.offset.left,
          top: $anchorDims.offset.top - ($eleDims.height + vOffset)
        };
        break;
      case 'left':
        return {
          left: $anchorDims.offset.left - ($eleDims.width + hOffset),
          top: $anchorDims.offset.top
        };
        break;
      case 'right':
        return {
          left: $anchorDims.offset.left + $anchorDims.width + hOffset,
          top: $anchorDims.offset.top
        };
        break;
      case 'center top':
        return {
          left: $anchorDims.offset.left + $anchorDims.width / 2 - $eleDims.width / 2,
          top: $anchorDims.offset.top - ($eleDims.height + vOffset)
        };
        break;
      case 'center bottom':
        return {
          left: isOverflow ? hOffset : $anchorDims.offset.left + $anchorDims.width / 2 - $eleDims.width / 2,
          top: $anchorDims.offset.top + $anchorDims.height + vOffset
        };
        break;
      case 'center left':
        return {
          left: $anchorDims.offset.left - ($eleDims.width + hOffset),
          top: $anchorDims.offset.top + $anchorDims.height / 2 - $eleDims.height / 2
        };
        break;
      case 'center right':
        return {
          left: $anchorDims.offset.left + $anchorDims.width + hOffset + 1,
          top: $anchorDims.offset.top + $anchorDims.height / 2 - $eleDims.height / 2
        };
        break;
      case 'center':
        return {
          left: $eleDims.windowDims.offset.left + $eleDims.windowDims.width / 2 - $eleDims.width / 2,
          top: $eleDims.windowDims.offset.top + $eleDims.windowDims.height / 2 - $eleDims.height / 2
        };
        break;
      case 'reveal':
        return {
          left: ($eleDims.windowDims.width - $eleDims.width) / 2,
          top: $eleDims.windowDims.offset.top + vOffset
        };
      case 'reveal full':
        return {
          left: $eleDims.windowDims.offset.left,
          top: $eleDims.windowDims.offset.top
        };
        break;
      case 'left bottom':
        return {
          left: $anchorDims.offset.left,
          top: $anchorDims.offset.top + $anchorDims.height + vOffset
        };
        break;
      case 'right bottom':
        return {
          left: $anchorDims.offset.left + $anchorDims.width + hOffset - $eleDims.width,
          top: $anchorDims.offset.top + $anchorDims.height + vOffset
        };
        break;
      default:
        return {
          left: Foundation.rtl() ? $anchorDims.offset.left - $eleDims.width + $anchorDims.width : $anchorDims.offset.left + hOffset,
          top: $anchorDims.offset.top + $anchorDims.height + vOffset
        };
    }
  }
}(jQuery);