Displaying events and all-day events.

Wino.Services/CalendarService.cs

@@ -1,8 +1,11 @@
 using System;
 using System.Collections.Generic;
+using System.Text.RegularExpressions;
 using System.Threading.Tasks;
 using CommunityToolkit.Mvvm.Messaging;
+using Ical.Net.DataTypes;
 using SqlKata;
+using Wino.Core.Domain;
 using Wino.Core.Domain.Entities.Calendar;
 using Wino.Core.Domain.Interfaces;
 using Wino.Messaging.Client.Calendar;
@@ -67,5 +70,54 @@ namespace Wino.Services
                    conn.InsertAll(attendees);
                });
         }
+
+        public async Task<List<ICalendarItem>> GetCalendarEventsAsync(Guid calendarId, DateTime rangeStart, DateTime rangeEnd)
+        {
+            // TODO: We might need to implement caching here.
+            // I don't know how much of the events we'll have in total, but this logic scans all events every time.
+
+            var accountEvents = await Connection.Table<CalendarItem>().Where(x => x.CalendarId == calendarId).ToListAsync();
+            var result = new List<ICalendarItem>();
+
+            foreach (var ev in accountEvents)
+            {
+                // Parse recurrence rules
+                var calendarEvent = new Ical.Net.CalendarComponents.CalendarEvent
+                {
+                    Start = new CalDateTime(ev.StartTime.UtcDateTime),
+                    Duration = TimeSpan.FromMinutes(ev.DurationInMinutes),
+                };
+
+                if (string.IsNullOrEmpty(ev.Recurrence))
+                {
+                    // No recurrence, only check if we fall into the date range.
+                    // All events are saved in UTC, so we need to convert the range to UTC as well.
+                    if (ev.StartTime.UtcDateTime < rangeEnd
+                        && ev.StartTime.UtcDateTime.AddMinutes(ev.DurationInMinutes) > rangeStart)
+                    {
+                        result.Add(ev);
+                    }
+                }
+                else
+                {
+                    var recurrenceLines = Regex.Split(ev.Recurrence, Constants.CalendarEventRecurrenceRuleSeperator);
+
+                    foreach (var line in recurrenceLines)
+                    {
+                        calendarEvent.RecurrenceRules.Add(new RecurrencePattern(line));
+                    }
+
+                    // Calculate occurrences in the range.
+                    var occurrences = calendarEvent.GetOccurrences(rangeStart, rangeEnd);
+
+                    foreach (var occurrence in occurrences)
+                    {
+                        result.Add(ev);
+                    }
+                }
+            }
+
+            return result;
+        }
     }
 }

Wino.Services/Wino.Services.csproj

@@ -7,6 +7,7 @@
 
   <ItemGroup>
     <PackageReference Include="HtmlAgilityPack" Version="1.11.70" />
+    <PackageReference Include="Ical.Net" Version="4.3.1" />
     <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="8.0.2" />
     <PackageReference Include="Serilog" Version="4.1.0" />
     <PackageReference Include="Serilog.Sinks.Debug" Version="3.0.0" />