(function() {
    "use strict";
    angular.module('raz')
        .service('resourcePopoverService', ['$document', function resourcePopoverService($document) {
            var bookPopover = {
                getDisplayInfo : null,
                closePopover : null,
                element: null
            };
            var nonbookPopover = {
                getDisplayInfo : null,
                closePopover : null,
                element: null
            };
            var currentPopoverTarget = {
                domElement : null,
                id: null
            };
            var popoverState = {
                popoverObject: null,
                enteredPopover: false,
                wasTouched: false,
                popoverActive: false,
                eventsEnabled: false
            };

            var _latestDisplayPopoverTimoutIds = [];
            var lastPopoverEnterCheckTimeoutId = null;
            var popoverEnterVerifyUtil = {
                setTimeoutToVerifyIfEnteredPopover : function(delayInMs) {
                    lastPopoverEnterCheckTimeoutId = setTimeout(function verifyIfEnteredPopover() {
                        if (!popoverState.enteredPopover) {
                            dismissPopover();
                        }
                    }, delayInMs);
                },
                resetPopoverEnterVerification: function() {
                    popoverState.enteredPopover = false;
                    if (popoverState.popoverObject != null) {
                        dismissPopover();
                    }
                    clearTimeout(lastPopoverEnterCheckTimeoutId);
                }
            };

            function registerBookPopover(getDisplayInfo, closePopover, element) {
                bookPopover.getDisplayInfo = getDisplayInfo;
                bookPopover.closePopover = closePopover;
                bookPopover.element = element;
            }

            function registerNonbookPopover(getDisplayInfo, closePopover, element) {
                nonbookPopover.getDisplayInfo = getDisplayInfo;
                nonbookPopover.closePopover = closePopover;
                nonbookPopover.element = element;
            }

            function enableEventTriggers(isBook) {
                disableEventTriggers(isBook);
                enablePopoverAreaEventTriggers(isBook);
                popoverState.eventsEnabled = true;
            }

            function disableEventTriggers(isBook) {
                var element = isBook ? bookPopover.element : nonbookPopover.element;
                element.off('mouseenter');
                var popoverContents = element.children().first();
                popoverContents.off('mouseleave');
                // remember in the state that the events are disabled
                popoverState.eventsEnabled = false;
            }

            function enablePopoverAreaEventTriggers(isBook) {
                var element = isBook ? bookPopover.element : nonbookPopover.element;
                element.on('mouseenter', function() {
                    popoverState.enteredPopover = true;
                    popoverState.wasTouched = false;
                });
                var popoverContents = element.children().first();
                popoverContents.on('mouseleave', function(e) {
                    popoverState.enteredPopover = false;
                    var delayInMs = 200;
                    popoverEnterVerifyUtil.setTimeoutToVerifyIfEnteredPopover(delayInMs);
                });
                popoverState.eventsEnabled = true;
            }

            function closeIfClickedOutsidePopover() {
                var onDocumentMouseDown = function(event) {
                    if (popoverState.popoverObject != null) {
                        var isChild = popoverState.popoverObject.element.find(event.target).length > 0;
                        var isMessageBox = angular.element(event.target).closest('.message-box').length > 0;
                        if(!isChild && !isMessageBox) {
                            popoverState.popoverObject.closePopover();
                        }
                    }
                };
                $document.on("mousedown " + getEventNames().startTouchEvent, onDocumentMouseDown);
            }

            function displayPopover(event, fromTouch, isBook, resourceInfo) {
                popoverState.popoverObject = isBook ? bookPopover : nonbookPopover;
                var resourceId = resourceInfo.resourceId;
                dismissPopover(event);
                var fromTouchParameter = fromTouch ? '&fromTouchDevice=y' : '';
                currentPopoverTarget.domElement = event.currentTarget;
                currentPopoverTarget.id = resourceId;

                popoverState.popoverObject.getDisplayInfo(fromTouchParameter, resourceInfo).then(function (response) {
                    var popoverDisplayTarget = $j(currentPopoverTarget.domElement).find('.thumbnail');
                    var foundThumbnailForDisplayTarget = popoverDisplayTarget.length !== 0;
                    if (!foundThumbnailForDisplayTarget) {
                        popoverDisplayTarget = $j(currentPopoverTarget.domElement).find('a');
                    }
                    var displayDelay = 150;
                    var latestTimeoutId = setTimeout(function() {
                        fadeInPopover(popoverDisplayTarget);
                    }, displayDelay);
                    _latestDisplayPopoverTimoutIds.push(latestTimeoutId);
                }).catch(function failure(response) {
                    console.error('couldn\'t fetch popover data\nresponse %o', response);
                });
            }

            function fadeInPopover(popoverDisplayTarget) {
                var popoverContents = popoverState.popoverObject.element.children().first();
                // "visibility maniuplation is needed for position() to work correctly
                popoverContents.css('visibility', 'hidden');
                popoverState.popoverObject.element.show(1, function() {
                    popoverContents.position({
                        my: 'left top',
                        at: 'right+12px top',
                        of: popoverDisplayTarget,
                        collision: 'flipfit'
                    });
                    popoverContents.hide();
                    popoverContents.css('visibility', 'visible');
                    popoverContents.fadeIn('fast');
                    popoverState.popoverActive = true;
                });
            }

            function dismissPopover(event) {
                var prevDisplayPopoverTimeoutIds = _latestDisplayPopoverTimoutIds;
                _latestDisplayPopoverTimoutIds = [];
                prevDisplayPopoverTimeoutIds.forEach(function(timeoutId) {
                    clearTimeout(timeoutId);
                });
                popoverState.popoverObject.closePopover();
                popoverState.popoverActive = false;
            }

            function getEventNames(){
                if('ontouchstart' in window)
                    return {startTouchEvent: 'touchstart', endTouchEvent: 'touchend', enterMouseEvent: 'mouseenter', leaveMouseEvent: 'mouseleave'};
                else if(window.PointerEvent)
                    return {startTouchEvent: 'pointerdown', endTouchEvent: 'pointerup', enterMouseEvent: 'pointerenter', leaveMouseEvent: 'pointerleave'};
                else
                    return {startTouchEvent: 'MSPointerDown', endTouchEvent: 'MSPointerUp', enterMouseEvent: 'mouseenter', leaveMouseEvent: 'mouseleave'};
            }

            return {
                registerBookPopover: registerBookPopover,
                registerNonbookPopover: registerNonbookPopover,
                enableEventTriggers: enableEventTriggers,
                disableEventTriggers: disableEventTriggers,
                closeIfClickedOutsidePopover: closeIfClickedOutsidePopover,
                displayPopover: displayPopover,
                popoverState: popoverState,
                popoverEnterVerifyUtil: popoverEnterVerifyUtil
            };
        }]);
})();