document.addEventListener('DOMContentLoaded', function() {

  var myCalendar = (function () {
  
    var canSubmit = false;
    var showFilteredEvents = true;
    var checkCalendarHeightTID;
    
    var allEvents = {
      startDate: '2024-07-09',
      endDate: '2024-07-09',
      currentView: $(window).width() < 767 ? 'listMonth' : 'dayGridMonth',
      eventList: [],
      start: function (date) {
        if (date && (date !== undefined)) {
          this.startDate = date;
          $('.fc-custom-search #start-date').val(date);
        } else {
          return this.startDate;
        }
      },
      end: function (date) {
        if (date && (date !== undefined)) {
          this.endDate = date;
          $('.fc-custom-search #end-date').val(date);
        } else {
          return this.endDate;
        }
      },
      view: function (view) {
        if (view && (view !== undefined)) {
          this.currentView = view;
          $('.fc-custom-search #view').val(view);
        } else {
          var formView = $('.fc-custom-search #view').val();
          if (formView && (formView !== undefined)) {
            this.currentView = formView;
          }
          return this.currentView;
        }
      },
      events: function (events) {
        if (events && (events !== undefined)) {
          this.eventList = events;
        } else {
          return this.eventList;
        }
      },
      eventSearchText: function (event) {
        var searchText = '';
        searchText = searchText + event.title.toLowerCase() + ' ';
        searchText = searchText + event.intro.toLowerCase() + ' ';
        if (event.school != null && event.school.length > 0) {
          for (var i = 0; i < event.school.length; i++) {
            searchText = searchText + event.school[i].toLowerCase() + ' ';
          }
        }
        return searchText;
      },
      filterBySchool: function (event) {
        var schools = $('#school-list').val();
        if (schools != null && schools.length == 1 && schools[0] == '') {
          return true;
        }
        if (schools != null && schools.length > 0) {
          if (event.school != null && event.school.length > 0) {
            for (var i = 0; i < schools.length; i++) {
              for (var j = 0; j < event.school.length; j++) {
                if (schools[i] == event.school[j]) {
                  return true;
                }
              }
            }
          } else {
            return false;
          }
        } else {
          return true;
        }
      },
      searchEvents: function (event) {
        var query = $('#search-query').val().toLowerCase();
        if (query != null && query.length > 0) {
          var queryTerms = query.split(/[ ,]+/).filter(Boolean);
          // "this." doesn't work for some reason I don't understand, so I use "allEvents." instead
          var searchText = allEvents.eventSearchText(event);
          for (var i = 0; i < queryTerms.length; i++) {
            if (searchText.search(queryTerms[i]) < 0) {
              return false;
            }
          }
          return true;
        } else {
          return true;
        }
      },
      filterEvents: function () {
        toggleFilterButtons();
        if (showFilteredEvents) {
          var filteredEvents = this.events().filter(this.filterBySchool);
          return filteredEvents.filter(this.searchEvents);
        } else {
          return this.events();
        }
      }
    };
    
    var showLoading = function () {
      $('.fc-view')
        .append($('<div class="fc-loading"><i class="fas fa-circle-notch fa-spin"></i></div>'))
        .show();
    }
    
    var hideLoading = function () {
      $('.fc-view .fc-loading').remove();
    }
    
    var adjustCalendarHeight = function () {
      fullHeight = $('.fc-scroller .fc-day-grid').height();
      if ($('.fc-scroller').height() < fullHeight) {
        $('.fc-scroller').height(fullHeight);
      }
      checkCalendarHeightTID = window.setTimeout(adjustCalendarHeight, 1000);
    }
    
    let startDate;            
    let endDate;
        
    const calendarEl = document.getElementById('calendar')
    const calendar = new FullCalendar.Calendar(calendarEl, {
      datesSet: function(dateInfo) {
        startDate = (String(dateInfo.start.toISOString())).slice(0,10);
        endDate = (String(dateInfo.end.toISOString())).slice(0,10);
        calendar.refetchEvents();
      },
      scrollTime: '08:00:00',
      editable: false, 
      nowIndicator: true,
      initialView : allEvents.view(), // window.innerWidth < 767 ? 'listMonth' : 'dayGridMonth',
      headerToolbar : { 
        start: 'today prev,next', 
        center: 'title', 
        end: 'dayGridWeek,dayGridMonth,timeGridDay,listMonth',
      },
      height: 'auto',
      themeSystem : 'bootstrap',
      eventColor: '#c4bfc0',
      eventTextColor: 'black',
      eventDisplay : 'block',
      eventSources : [
        {
          events: function(info, successCallback, failureCallback) {
            
            if (allEvents.start() != startDate || allEvents.end() != endDate) {
              
              allEvents.start(startDate);
              allEvents.end(endDate);
              
              $.ajax({
                url: 'https://engineering.purdue.edu/Engr/InfoFor/Parents/coe-calendar-widget/scripts/pyGetCalendarEvents',
                type: 'GET',
                dataType: 'json',
                cache: true,
                data: {
                  start: startDate,
                  end: endDate,
                },
                success: function (events) {
                  allEvents.events(events);
                  successCallback(allEvents.filterEvents());
                },
                error: function () {
                  failureCallback('There was an error fetching the JSON events.');
                }                    
              });
            } else {
              successCallback(allEvents.filterEvents());
            }
            
          }
        }
      ],
      eventClick: function (event) {
        if (event.url) {
          window.open(event.url, '_blank');
          return false;
        }
      },      
      eventDidMount: function(info) {
            var originalLeave;
            $(info.el).popover({
                title: info.event.title,
                placement: 'right',
                content: () => {
                  let time = () => {
                   if (info.event.allDay == false) {
                     return (
                       '<strong>Time:</strong> ' + info.event.extendedProps.event_times.t_start.t_str + ' to ' + info.event.extendedProps.event_times.t_end.t_str + '<br>');
                   } else {
                     return ('<strong>Time:</strong> All Day <br>');
                   }
                  };
                  let intro = ('<strong>Intro:</strong> ' + (info.event.extendedProps.intro) + '<br>');
                  let location = () => {
                    if (info.event.extendedProps.location != 'undefined') {
                      return ('<strong>Location:</strong> ' + info.event.extendedProps.location + '<br>');
                    } else {
                      return ('<strong>Location:</strong> None Given <br>');
                    }
                  };
                  let schoolOrProgram = () => {
                    if (info.event.extendedProps.school != '') {
                      return '<strong>School or Program:</strong> ' + info.event.extendedProps.school + '<br>';
                    } else {
                      return ('<strong>School or Program:</strong> Open' + '<br>');
                    }
                  };

                  let atc = () => {
                    if (info.event.allDay == false) {
                      return (
                        '<add-to-calendar-button ' +
                        'name="' + info.event.title + '" ' +
                        'description="' + info.event.extendedProps.intro + '" ' +
                        'options="&#39;Apple&#39;&#44;&#39;Google&#39;&#44;&#39;iCal&#39;&#44;&#39;Outlook.com&#39;&#44;&#39;Yahoo&#39;" ' + 
                        'location="' + info.event.extendedProps.location + '" ' +
                        'startDate="' + info.event.start.toISOString().slice(0,10) + '" ' +
                        'endDate="' + info.event.start.toISOString().slice(0,10) + '" ' +
                        'startTime="' + info.event.extendedProps.event_times.start.slice(0,5) + '" ' +
                        'endTime="' + info.event.extendedProps.event_times.end.slice(0,5) + '" ' +
                        'timeZone="America/Indiana/Indianapolis" ' +
                        'trigger = "click" ' +
                        'size = "4" ' +
                        'styleLight="--wrapper-padding: 10px 0px;" ' +
                        'buttonStyle="flat" ' +
                        'customCss="https://engineering.purdue.edu/Engr/InfoFor/Parents/coe-calendar-widget/scripts/css/atcb.css" ' +
                        'label="ADD TO CALENDAR" ' +
                        'hideBackground ' +
                        'hideCheckmark' +
                        '></add-to-calendar-button>'
                      );
                    } else {
                      return (
                        '<add-to-calendar-button ' +
                        'name="' + info.event.title + '" ' +
                        'description="' + info.event.extendedProps.intro + '" ' +
                        'options="&#39;Apple&#39;&#44;&#39;Google&#39;&#44;&#39;iCal&#39;&#44;&#39;Outlook.com&#39;&#44;&#39;Yahoo&#39;" ' + 
                        'location="' + info.event.extendedProps.location + '" ' +
                        'startDate="' + info.event.start.toISOString().slice(0,10) + '" ' +
                        'endDate="' + info.event.start.toISOString().slice(0,10) + '" ' +
                        'startTime="" ' +
                        'endTime="" ' +
                        'timeZone="America/Indiana/Indianapolis" ' +
                        'trigger = "click" ' +
                        'size = "4" ' +
                        'styleLight="--wrapper-padding: 10px 0px;" ' +
                        'buttonStyle="flat" ' +
                        'customCss="https://engineering.purdue.edu/Engr/InfoFor/Parents/coe-calendar-widget/scripts/css/atcb.css" ' +
                        'label="ADD TO CALENDAR" ' +
                        'hideBackground ' +
                        'hideCheckmark' +
                        '></add-to-calendar-button>'
                      );
                    };
                  }

                  return ( time() + intro + location() + schoolOrProgram() + atc() )
                },
                trigger: 'manual',
                container: 'body',
                html: true
            }).on('mouseenter', function() {
                var _this = this;
                $(this).popover('show');
                $('.popover').on('mouseleave', function() {
                    $(_this).popover('hide');
                });
            }).on('mouseleave', function() {
                var _this = this;
                setTimeout(function() {
                    if (!$('.popover:hover').length) {
                        $(_this).popover('hide');
                    }
                }, 100); // Timeout for mouse to possibly move from event to popover
            });
  
            // Correct handling of Popover's manual triggering
            $('.popover').off('mouseenter').on('mouseenter', function() {
                if (originalLeave) {
                    clearTimeout(originalLeave);
                }
            });
        },
  
    })
    
    calendar.render()
    
    var refetchEvents = function () {
      calendar.refetchEvents();
    }
    
    var showFilteredEvents = function () {
      showFilteredEvents = true;
      toggleFilterButtons();
      refetchEvents();
    }
    
    var showAllEvents = function () {
      showFilteredEvents = false;
      toggleFilterButtons();
      refetchEvents();
    }
    
    var toggleFilterButtons = function (show) {
      if (showFilteredEvents) {
        $('#show-filtered-events').addClass('fc-state-active');
        $('#show-all-events').removeClass('fc-state-active');
      } else {
        $('#show-filtered-events').removeClass('fc-state-active');
        $('#show-all-events').addClass('fc-state-active');
      }
    }   
    
    
    $('#school-list').change(function (event) {
      refetchEvents();
      event.preventDefault();
    });
    
    $('#search-query').change(function (event) {
      refetchEvents();
      // enable the following line to make the form submit only when the submit button is clicked
      // event.preventDefault();  
    }).keyup(function () {
      $(this).change();
    });
    
    $('.clear-search').click(function (event) {
      // document.getElementById('fc-custom-search').reset();
      $('#fc-custom-search option').prop("selected", false);
      $('#search-query').val('');
      // event.preventDefault();
      // $('.search-results').remove();
      // showFilteredEvents = false;
      // toggleFilterButtons();
      // refetchEvents();
    });
    
    $('#show-filtered-events').click(showFilteredEvents);
    $('#show-all-events').click(showAllEvents);
    
    return {
      showFilteredEvents: showFilteredEvents,
      showAllEvents: showAllEvents
    };
        
  })(); 
  
})