@react-jvectormap/jquery-mousewheel/jquery.mousewheel.js

A jQuery plugin that adds cross-browser mouse wheel support.

/*!
 * jQuery Mousewheel 3.1.13
 * Copyright OpenJS Foundation and other contributors
 */

export const loadJQueryMouseWheel = ($) =>
  (function (factory) {
    factory($);
  })(function ($) {
    var toFix = [
        "wheel",
        "mousewheel",
        "DOMMouseScroll",
        "MozMousePixelScroll",
      ],
      toBind =
        "onwheel" in window.document || window.document.documentMode >= 9
          ? ["wheel"]
          : ["mousewheel", "DomMouseScroll", "MozMousePixelScroll"],
      slice = Array.prototype.slice,
      nullLowestDeltaTimeout,
      lowestDelta;

    if ($.event.fixHooks) {
      for (var i = toFix.length; i; ) {
        $.event.fixHooks[toFix[--i]] = $.event.mouseHooks;
      }
    }

    var special = ($.event.special.mousewheel = {
      version: "3.1.12",

      setup: function () {
        if (this.addEventListener) {
          for (var i = toBind.length; i; ) {
            this.addEventListener(toBind[--i], handler, false);
          }
        } else {
          this.onmousewheel = handler;
        }

        // Store the line height and page height for this particular element
        $.data(this, "mousewheel-line-height", special.getLineHeight(this));
        $.data(this, "mousewheel-page-height", special.getPageHeight(this));
      },

      teardown: function () {
        if (this.removeEventListener) {
          for (var i = toBind.length; i; ) {
            this.removeEventListener(toBind[--i], handler, false);
          }
        } else {
          this.onmousewheel = null;
        }

        // Clean up the data we added to the element
        $.removeData(this, "mousewheel-line-height");
        $.removeData(this, "mousewheel-page-height");
      },

      getLineHeight: function (elem) {
        var $elem = $(elem),
          $parent = $elem["offsetParent" in $.fn ? "offsetParent" : "parent"]();
        if (!$parent.length) {
          $parent = $("body");
        }
        return (
          parseInt($parent.css("fontSize"), 10) ||
          parseInt($elem.css("fontSize"), 10) ||
          16
        );
      },

      getPageHeight: function (elem) {
        return $(elem).height();
      },

      settings: {
        adjustOldDeltas: true, // see shouldAdjustOldDeltas() below
        normalizeOffset: true, // calls getBoundingClientRect for each event
      },
    });

    $.fn.extend({
      mousewheel: function (fn) {
        return fn ? this.on("mousewheel", fn) : this.trigger("mousewheel");
      },

      unmousewheel: function (fn) {
        return this.off("mousewheel", fn);
      },
    });

    function handler(event) {
      var orgEvent = event || window.event,
        args = slice.call(arguments, 1),
        delta = 0,
        deltaX = 0,
        deltaY = 0,
        absDelta = 0;
      event = $.event.fix(orgEvent);
      event.type = "mousewheel";

      // Old school scrollwheel delta
      if ("detail" in orgEvent) {
        deltaY = orgEvent.detail * -1;
      }
      if ("wheelDelta" in orgEvent) {
        deltaY = orgEvent.wheelDelta;
      }
      if ("wheelDeltaY" in orgEvent) {
        deltaY = orgEvent.wheelDeltaY;
      }
      if ("wheelDeltaX" in orgEvent) {
        deltaX = orgEvent.wheelDeltaX * -1;
      }

      // Firefox < 17 horizontal scrolling related to DOMMouseScroll event
      if ("axis" in orgEvent && orgEvent.axis === orgEvent.HORIZONTAL_AXIS) {
        deltaX = deltaY * -1;
        deltaY = 0;
      }

      // Set delta to be deltaY or deltaX if deltaY is 0 for backwards compatabilitiy
      delta = deltaY === 0 ? deltaX : deltaY;

      // New school wheel delta (wheel event)
      if ("deltaY" in orgEvent) {
        deltaY = orgEvent.deltaY * -1;
        delta = deltaY;
      }
      if ("deltaX" in orgEvent) {
        deltaX = orgEvent.deltaX;
        if (deltaY === 0) {
          delta = deltaX * -1;
        }
      }

      // No change actually happened, no reason to go any further
      if (deltaY === 0 && deltaX === 0) {
        return;
      }

      // Need to convert lines and pages to pixels if we aren't already in pixels
      // There are three delta modes:
      //   * deltaMode 0 is by pixels, nothing to do
      //   * deltaMode 1 is by lines
      //   * deltaMode 2 is by pages
      if (orgEvent.deltaMode === 1) {
        var lineHeight = $.data(this, "mousewheel-line-height");
        delta *= lineHeight;
        deltaY *= lineHeight;
        deltaX *= lineHeight;
      } else if (orgEvent.deltaMode === 2) {
        var pageHeight = $.data(this, "mousewheel-page-height");
        delta *= pageHeight;
        deltaY *= pageHeight;
        deltaX *= pageHeight;
      }

      // Store lowest absolute delta to normalize the delta values
      absDelta = Math.max(Math.abs(deltaY), Math.abs(deltaX));

      if (!lowestDelta || absDelta < lowestDelta) {
        lowestDelta = absDelta;

        // Adjust older deltas if necessary
        if (shouldAdjustOldDeltas(orgEvent, absDelta)) {
          lowestDelta /= 40;
        }
      }

      // Adjust older deltas if necessary
      if (shouldAdjustOldDeltas(orgEvent, absDelta)) {
        // Divide all the things by 40!
        delta /= 40;
        deltaX /= 40;
        deltaY /= 40;
      }

      // Get a whole, normalized value for the deltas
      delta = Math[delta >= 1 ? "floor" : "ceil"](delta / lowestDelta);
      deltaX = Math[deltaX >= 1 ? "floor" : "ceil"](deltaX / lowestDelta);
      deltaY = Math[deltaY >= 1 ? "floor" : "ceil"](deltaY / lowestDelta);

      // Normalise offsetX and offsetY properties
      if (special.settings.normalizeOffset && this.getBoundingClientRect) {
        var boundingRect = this.getBoundingClientRect();
        event.offsetX = event.clientX - boundingRect.left;
        event.offsetY = event.clientY - boundingRect.top;
      }

      // Add information to the event object
      event.deltaX = deltaX;
      event.deltaY = deltaY;
      event.deltaFactor = lowestDelta;

      // Go ahead and set deltaMode to 0 since we converted to pixels
      // Although this is a little odd since we overwrite the deltaX/Y
      // properties with normalized deltas.
      event.deltaMode = 0;

      // Add event and delta to the front of the arguments
      args.unshift(event, delta, deltaX, deltaY);

      // Clearout lowestDelta after sometime to better
      // handle multiple device types that give different
      // a different lowestDelta
      // Ex: trackpad = 3 and mouse wheel = 120
      if (nullLowestDeltaTimeout) {
        window.clearTimeout(nullLowestDeltaTimeout);
      }
      nullLowestDeltaTimeout = window.setTimeout(nullLowestDelta, 200);

      return ($.event.dispatch || $.event.handle).apply(this, args);
    }

    function nullLowestDelta() {
      lowestDelta = null;
    }

    function shouldAdjustOldDeltas(orgEvent, absDelta) {
      // If this is an older event and the delta is divisable by 120,
      // then we are assuming that the browser is treating this as an
      // older mouse wheel event and that we should divide the deltas
      // by 40 to try and get a more usable deltaFactor.
      // Side note, this actually impacts the reported scroll distance
      // in older browsers and can cause scrolling to be slower than native.
      // Turn this off by setting $.event.special.mousewheel.settings.adjustOldDeltas to false.
      return (
        special.settings.adjustOldDeltas &&
        orgEvent.type === "mousewheel" &&
        absDelta % 120 === 0
      );
    }
  });