/*!
 * better-scroll / pull-down
 * (c) 2016-2021 ustbhuangyi
 * Released under the MIT License.
 */
(function (global, factory) {
  typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
  typeof define === 'function' && define.amd ? define(factory) :
  (global = typeof globalThis !== 'undefined' ? globalThis : global || self, global.PullDown = factory());
}(this, (function () { 'use strict';

  // ssr support
  var inBrowser = typeof window !== 'undefined';
  var ua = inBrowser && navigator.userAgent.toLowerCase();
  !!(ua && /wechatdevtools/.test(ua));
  ua && ua.indexOf('android') > 0;
  /* istanbul ignore next */
  ((function () {
      if (typeof ua === 'string') {
          var regex = /os (\d\d?_\d(_\d)?)/;
          var matches = regex.exec(ua);
          if (!matches)
              return false;
          var parts = matches[1].split('_').map(function (item) {
              return parseInt(item, 10);
          });
          // ios version >= 13.4 issue 982
          return !!(parts[0] === 13 && parts[1] >= 4);
      }
      return false;
  }))();
  /* istanbul ignore next */
  var supportsPassive = false;
  /* istanbul ignore next */
  if (inBrowser) {
      var EventName = 'test-passive';
      try {
          var opts = {};
          Object.defineProperty(opts, 'passive', {
              get: function () {
                  supportsPassive = true;
              },
          }); // https://github.com/facebook/flow/issues/285
          window.addEventListener(EventName, function () { }, opts);
      }
      catch (e) { }
  }

  var extend = function (target, source) {
      for (var key in source) {
          target[key] = source[key];
      }
      return target;
  };

  var elementStyle = (inBrowser &&
      document.createElement('div').style);
  var vendor = (function () {
      /* istanbul ignore if  */
      if (!inBrowser) {
          return false;
      }
      var transformNames = [
          {
              key: 'standard',
              value: 'transform',
          },
          {
              key: 'webkit',
              value: 'webkitTransform',
          },
          {
              key: 'Moz',
              value: 'MozTransform',
          },
          {
              key: 'O',
              value: 'OTransform',
          },
          {
              key: 'ms',
              value: 'msTransform',
          },
      ];
      for (var _i = 0, transformNames_1 = transformNames; _i < transformNames_1.length; _i++) {
          var obj = transformNames_1[_i];
          if (elementStyle[obj.value] !== undefined) {
              return obj.key;
          }
      }
      /* istanbul ignore next  */
      return false;
  })();
  /* istanbul ignore next  */
  function prefixStyle(style) {
      if (vendor === false) {
          return style;
      }
      if (vendor === 'standard') {
          if (style === 'transitionEnd') {
              return 'transitionend';
          }
          return style;
      }
      return vendor + style.charAt(0).toUpperCase() + style.substr(1);
  }
  vendor && vendor !== 'standard' ? '-' + vendor.toLowerCase() + '-' : '';
  var transform = prefixStyle('transform');
  var transition = prefixStyle('transition');
  inBrowser && prefixStyle('perspective') in elementStyle;
  ({
      transform: transform,
      transition: transition,
      transitionTimingFunction: prefixStyle('transitionTimingFunction'),
      transitionDuration: prefixStyle('transitionDuration'),
      transitionDelay: prefixStyle('transitionDelay'),
      transformOrigin: prefixStyle('transformOrigin'),
      transitionEnd: prefixStyle('transitionEnd'),
      transitionProperty: prefixStyle('transitionProperty'),
  });

  var ease = {
      // easeOutQuint
      swipe: {
          style: 'cubic-bezier(0.23, 1, 0.32, 1)',
          fn: function (t) {
              return 1 + --t * t * t * t * t;
          }
      },
      // easeOutQuard
      swipeBounce: {
          style: 'cubic-bezier(0.25, 0.46, 0.45, 0.94)',
          fn: function (t) {
              return t * (2 - t);
          }
      },
      // easeOutQuart
      bounce: {
          style: 'cubic-bezier(0.165, 0.84, 0.44, 1)',
          fn: function (t) {
              return 1 - --t * t * t * t;
          }
      }
  };

  var sourcePrefix = 'plugins.pullDownRefresh';
  var propertiesMap = [
      {
          key: 'finishPullDown',
          name: 'finishPullDown'
      },
      {
          key: 'openPullDown',
          name: 'openPullDown'
      },
      {
          key: 'closePullDown',
          name: 'closePullDown'
      },
      {
          key: 'autoPullDownRefresh',
          name: 'autoPullDownRefresh'
      }
  ];
  var propertiesConfig = propertiesMap.map(function (item) {
      return {
          key: item.key,
          sourceKey: sourcePrefix + "." + item.name
      };
  });

  var PULLING_DOWN_EVENT = 'pullingDown';
  var ENTER_THRESHOLD_EVENT = 'enterThreshold';
  var LEAVE_THRESHOLD_EVENT = 'leaveThreshold';
  var PullDown = /** @class */ (function () {
      function PullDown(scroll) {
          this.scroll = scroll;
          this.pulling = 0 /* DEFAULT */;
          this.thresholdBoundary = 0 /* DEFAULT */;
          this.init();
      }
      PullDown.prototype.setPulling = function (status) {
          this.pulling = status;
      };
      PullDown.prototype.setThresholdBoundary = function (boundary) {
          this.thresholdBoundary = boundary;
      };
      PullDown.prototype.init = function () {
          this.handleBScroll();
          this.handleOptions(this.scroll.options.pullDownRefresh);
          this.handleHooks();
          this.watch();
      };
      PullDown.prototype.handleBScroll = function () {
          this.scroll.registerType([
              PULLING_DOWN_EVENT,
              ENTER_THRESHOLD_EVENT,
              LEAVE_THRESHOLD_EVENT,
          ]);
          this.scroll.proxy(propertiesConfig);
      };
      PullDown.prototype.handleOptions = function (userOptions) {
          if (userOptions === void 0) { userOptions = {}; }
          userOptions = (userOptions === true ? {} : userOptions);
          var defaultOptions = {
              threshold: 90,
              stop: 40,
          };
          this.options = extend(defaultOptions, userOptions);
          this.scroll.options.probeType = 3 /* Realtime */;
      };
      PullDown.prototype.handleHooks = function () {
          var _this = this;
          this.hooksFn = [];
          var scroller = this.scroll.scroller;
          var scrollBehaviorY = scroller.scrollBehaviorY;
          this.currentMinScrollY = this.cachedOriginanMinScrollY =
              scrollBehaviorY.minScrollPos;
          this.registerHooks(this.scroll.hooks, this.scroll.hooks.eventTypes.contentChanged, function () {
              _this.finishPullDown();
          });
          this.registerHooks(scrollBehaviorY.hooks, scrollBehaviorY.hooks.eventTypes.computeBoundary, function (boundary) {
              // content is smaller than wrapper
              if (boundary.maxScrollPos > 0) {
                  // allow scrolling when content is not full of wrapper
                  boundary.maxScrollPos = -1;
              }
              boundary.minScrollPos = _this.currentMinScrollY;
          });
          // integrate with mousewheel
          if (this.hasMouseWheelPlugin()) {
              this.registerHooks(this.scroll, this.scroll.eventTypes.alterOptions, function (mouseWheelOptions) {
                  var SANE_DISCRETE_TIME = 300;
                  var SANE_EASE_TIME = 350;
                  mouseWheelOptions.discreteTime = SANE_DISCRETE_TIME;
                  // easeTime > discreteTime ensure goInto checkPullDown function
                  mouseWheelOptions.easeTime = SANE_EASE_TIME;
              });
              this.registerHooks(this.scroll, this.scroll.eventTypes.mousewheelEnd, function () {
                  // mouseWheel need trigger checkPullDown manually
                  scroller.hooks.trigger(scroller.hooks.eventTypes.end);
              });
          }
      };
      PullDown.prototype.registerHooks = function (hooks, name, handler) {
          hooks.on(name, handler, this);
          this.hooksFn.push([hooks, name, handler]);
      };
      PullDown.prototype.hasMouseWheelPlugin = function () {
          return !!this.scroll.eventTypes.alterOptions;
      };
      PullDown.prototype.watch = function () {
          var scroller = this.scroll.scroller;
          this.watching = true;
          this.registerHooks(scroller.hooks, scroller.hooks.eventTypes.end, this.checkPullDown);
          this.registerHooks(this.scroll, this.scroll.eventTypes.scrollStart, this.resetStateBeforeScrollStart);
          this.registerHooks(this.scroll, this.scroll.eventTypes.scroll, this.checkLocationOfThresholdBoundary);
          if (this.hasMouseWheelPlugin()) {
              this.registerHooks(this.scroll, this.scroll.eventTypes.mousewheelStart, this.resetStateBeforeScrollStart);
          }
      };
      PullDown.prototype.resetStateBeforeScrollStart = function () {
          // current fetching pulldownRefresh has ended
          if (!this.isFetchingStatus()) {
              this.setPulling(1 /* MOVING */);
              this.setThresholdBoundary(0 /* DEFAULT */);
          }
      };
      PullDown.prototype.checkLocationOfThresholdBoundary = function () {
          // pulldownRefresh is in the phase of Moving
          if (this.pulling === 1 /* MOVING */) {
              var scroll_1 = this.scroll;
              // enter threshold boundary
              var enteredThresholdBoundary = this.thresholdBoundary !== 1 /* INSIDE */ &&
                  this.locateInsideThresholdBoundary();
              // leave threshold boundary
              var leftThresholdBoundary = this.thresholdBoundary !== 2 /* OUTSIDE */ &&
                  !this.locateInsideThresholdBoundary();
              if (enteredThresholdBoundary) {
                  this.setThresholdBoundary(1 /* INSIDE */);
                  scroll_1.trigger(ENTER_THRESHOLD_EVENT);
              }
              if (leftThresholdBoundary) {
                  this.setThresholdBoundary(2 /* OUTSIDE */);
                  scroll_1.trigger(LEAVE_THRESHOLD_EVENT);
              }
          }
      };
      PullDown.prototype.locateInsideThresholdBoundary = function () {
          return this.scroll.y <= this.options.threshold;
      };
      PullDown.prototype.unwatch = function () {
          var scroll = this.scroll;
          var scroller = scroll.scroller;
          this.watching = false;
          scroller.hooks.off(scroller.hooks.eventTypes.end, this.checkPullDown);
          scroll.off(scroll.eventTypes.scrollStart, this.resetStateBeforeScrollStart);
          scroll.off(scroll.eventTypes.scroll, this.checkLocationOfThresholdBoundary);
          if (this.hasMouseWheelPlugin()) {
              scroll.off(scroll.eventTypes.mousewheelStart, this.resetStateBeforeScrollStart);
          }
      };
      PullDown.prototype.checkPullDown = function () {
          var _a = this.options, threshold = _a.threshold, stop = _a.stop;
          // check if a real pull down action
          if (this.scroll.y < threshold) {
              return false;
          }
          if (this.pulling === 1 /* MOVING */) {
              this.modifyBehaviorYBoundary(stop);
              this.setPulling(2 /* FETCHING */);
              this.scroll.trigger(PULLING_DOWN_EVENT);
          }
          this.scroll.scrollTo(this.scroll.x, stop, this.scroll.options.bounceTime, ease.bounce);
          return this.isFetchingStatus();
      };
      PullDown.prototype.isFetchingStatus = function () {
          return this.pulling === 2 /* FETCHING */;
      };
      PullDown.prototype.modifyBehaviorYBoundary = function (stopDistance) {
          var scrollBehaviorY = this.scroll.scroller.scrollBehaviorY;
          // manually modify minScrollPos for a hang animation
          // to prevent from resetPosition
          this.cachedOriginanMinScrollY = scrollBehaviorY.minScrollPos;
          this.currentMinScrollY = stopDistance;
          scrollBehaviorY.computeBoundary();
      };
      PullDown.prototype.finishPullDown = function () {
          if (this.isFetchingStatus()) {
              var scrollBehaviorY = this.scroll.scroller.scrollBehaviorY;
              // restore minScrollY since the hang animation has ended
              this.currentMinScrollY = this.cachedOriginanMinScrollY;
              scrollBehaviorY.computeBoundary();
              this.setPulling(0 /* DEFAULT */);
              this.scroll.resetPosition(this.scroll.options.bounceTime, ease.bounce);
          }
      };
      // allow 'true' type is compat for beta version implements
      PullDown.prototype.openPullDown = function (config) {
          if (config === void 0) { config = {}; }
          this.handleOptions(config);
          if (!this.watching) {
              this.watch();
          }
      };
      PullDown.prototype.closePullDown = function () {
          this.unwatch();
      };
      PullDown.prototype.autoPullDownRefresh = function () {
          var _a = this.options, threshold = _a.threshold, stop = _a.stop;
          if (this.isFetchingStatus() || !this.watching) {
              return;
          }
          this.modifyBehaviorYBoundary(stop);
          this.scroll.trigger(this.scroll.eventTypes.scrollStart);
          this.scroll.scrollTo(this.scroll.x, threshold);
          this.setPulling(2 /* FETCHING */);
          this.scroll.trigger(PULLING_DOWN_EVENT);
          this.scroll.scrollTo(this.scroll.x, stop, this.scroll.options.bounceTime, ease.bounce);
      };
      PullDown.pluginName = 'pullDownRefresh';
      return PullDown;
  }());

  return PullDown;

})));