2gis-maps/vendors/baron/src/pull.js

Interactive 2GIS maps API, based on Leaflet

/* Pull to load plugin for baron 0.6+ */
(function(window, undefined) {
    var pull = function(params) {
        var block = this.$(params.block),
            size = params.size || this.origin.size,
            limit = params.limit || 80,
            onExpand = params.onExpand,
            elements = params.elements || [],
            inProgress = params.inProgress || '',
            self = this,
            _insistence = 0,
            _zeroXCount = 0,
            _interval,
            _timer,
            _x = 0,
            _onExpandCalled,
            _waiting = params.waiting || 500,
            _on;

        function getSize() {
            return self.scroller[self.origin.scroll] + self.scroller[self.origin.offset];
        }

        // Scroller content height
        function getContentSize() {
            return self.scroller[self.origin.scrollSize];
        }

        // Scroller height
        function getScrollerSize() {
            return self.scroller[self.origin.client];
        }

        function step(x, force) {
            var k = x * 0.0005;
            
            return Math.floor(force - k * (x + 550));
        }

        function toggle(on) {
            _on = on;

            if (on) {
                update(); // First time with no delay
                _interval = setInterval(update, 200);
            } else {
                clearInterval(_interval);
            }
        }

        function update() {
            var pos = {},
                height = getSize(),
                scrollHeight = getContentSize(),
                dx,
                op4,
                scrollInProgress = _insistence == 1;

            op4 = 0; // Возвращающая сила
            if (_insistence > 0) {
                op4 = 40;
            }
            //if (_insistence > -1) {
                dx = step(_x, op4);
                if (height >= scrollHeight - _x && _insistence > -1) {
                    if (scrollInProgress) {
                        _x += dx;
                    }
                } else {
                    _x = 0;
                }

                if (_x < 0) _x = 0;

                pos[size] = _x + 'px';
                if (getScrollerSize() <= getContentSize()) {
                    self.$(block).css(pos);
                    for (var i = 0 ; i < elements.length ; i++) {
                        self.$(elements[i].self).css(elements[i].property, Math.min(_x / limit * 100, 100) + '%');
                    }
                }

                if (inProgress && _x) {
                    self.$(self.root).addClass(inProgress);
                }

                if (_x == 0) {
                    if (params.onCollapse) {
                        params.onCollapse();
                    }
                }

                _insistence = 0;
                _timer = setTimeout(function() {
                    _insistence = -1;
                }, _waiting);
            //}

            if (onExpand && _x > limit && !_onExpandCalled) {
                onExpand();
                _onExpandCalled = true;
            }

            if (_x == 0) {
                _zeroXCount++;
            } else {
                _zeroXCount = 0;
                
            }
            if (_zeroXCount > 1) {
                toggle(false);
                _onExpandCalled = false;
                if (inProgress) {
                    self.$(self.root).removeClass(inProgress);
                }
            }
        }

        this.on('init', function() {
            toggle(true);
        });

        this.on('dispose', function() {
            toggle(false);
        });

        this.event(this.scroller, 'mousewheel DOMMouseScroll', function(e) {
            var down = e.wheelDelta < 0 || (e.originalEvent && e.originalEvent.wheelDelta < 0) || e.detail > 0;

            if (down) {
                _insistence = 1;
                clearTimeout(_timer);
                if (!_on && getSize() >= getContentSize()) {
                    toggle(true);
                }
            }
            //  else {
            //     toggle(false);
            // }
        });
    };

    baron.fn.pull = function(params) {
        var i = 0;

        while (this[i]) {
            pull.call(this[i], params);
            i++;
        }

        return this;
    };
})(window);