fix collections paging (#171)

ErsatzTV.Application/Configuration/Commands/SaveConfigElementByKey.cs

@@ -0,0 +1,7 @@
+using ErsatzTV.Core.Domain;
+using MediatR;
+
+namespace ErsatzTV.Application.Configuration.Commands
+{
+    public record SaveConfigElementByKey(ConfigElementKey Key, string Value) : IRequest<LanguageExt.Unit>;
+}

ErsatzTV.Application/Configuration/Commands/SaveConfigElementByKeyHandler.cs

@@ -0,0 +1,34 @@
+using System.Threading;
+using System.Threading.Tasks;
+using ErsatzTV.Core.Domain;
+using ErsatzTV.Core.Interfaces.Repositories;
+using LanguageExt;
+
+namespace ErsatzTV.Application.Configuration.Commands
+{
+    public class SaveConfigElementByKeyHandler : MediatR.IRequestHandler<SaveConfigElementByKey, Unit>
+    {
+        private readonly IConfigElementRepository _configElementRepository;
+
+        public SaveConfigElementByKeyHandler(IConfigElementRepository configElementRepository) =>
+            _configElementRepository = configElementRepository;
+
+        public async Task<Unit> Handle(SaveConfigElementByKey request, CancellationToken cancellationToken)
+        {
+            Option<ConfigElement> maybeElement = await _configElementRepository.Get(request.Key);
+            await maybeElement.Match(
+                ce =>
+                {
+                    ce.Value = request.Value;
+                    return _configElementRepository.Update(ce);
+                },
+                () =>
+                {
+                    var ce = new ConfigElement { Key = request.Key.Key, Value = request.Value };
+                    return _configElementRepository.Add(ce);
+                });
+
+            return Unit.Default;
+        }
+    }
+}

ErsatzTV.Application/Configuration/ConfigElementViewModel.cs

@@ -0,0 +1,4 @@
+namespace ErsatzTV.Application.Configuration
+{
+    public record ConfigElementViewModel(string Key, string Value);
+}

ErsatzTV.Application/Configuration/Mapper.cs

@@ -0,0 +1,8 @@
+namespace ErsatzTV.Application.Configuration
+{
+    internal static class Mapper
+    {
+        internal static ConfigElementViewModel ProjectToViewModel(Core.Domain.ConfigElement element) =>
+            new(element.Key, element.Value);
+    }
+}

ErsatzTV.Application/Configuration/Queries/GetConfigElementByKey.cs

@@ -0,0 +1,8 @@
+using ErsatzTV.Core.Domain;
+using LanguageExt;
+using MediatR;
+
+namespace ErsatzTV.Application.Configuration.Queries
+{
+    public record GetConfigElementByKey(ConfigElementKey Key) : IRequest<Option<ConfigElementViewModel>>;
+}

ErsatzTV.Application/Configuration/Queries/GetConfigElementByKeyHandler.cs

@@ -0,0 +1,22 @@
+using System.Threading;
+using System.Threading.Tasks;
+using ErsatzTV.Core.Interfaces.Repositories;
+using LanguageExt;
+using MediatR;
+using static ErsatzTV.Application.Configuration.Mapper;
+
+namespace ErsatzTV.Application.Configuration.Queries
+{
+    public class GetConfigElementByKeyHandler : IRequestHandler<GetConfigElementByKey, Option<ConfigElementViewModel>>
+    {
+        private readonly IConfigElementRepository _configElementRepository;
+
+        public GetConfigElementByKeyHandler(IConfigElementRepository configElementRepository) =>
+            _configElementRepository = configElementRepository;
+
+        public Task<Option<ConfigElementViewModel>> Handle(
+            GetConfigElementByKey request,
+            CancellationToken cancellationToken) =>
+            _configElementRepository.Get(request.Key).MapT(ProjectToViewModel);
+    }
+}

ErsatzTV.Application/FFmpegProfiles/Commands/UpdateFFmpegSettingsHandler.cs

@@ -86,8 +86,10 @@ namespace ErsatzTV.Application.FFmpegProfiles.Commands
             return Unit.Default;
         }
 
-        private Task Upsert(ConfigElementKey key, string value) =>
-            _configElementRepository.Get(key).Match(
+        private async Task Upsert(ConfigElementKey key, string value)
+        {
+            Option<ConfigElement> maybeElement = await _configElementRepository.Get(key); 
+            await maybeElement.Match(
                 ce =>
                 {
                     ce.Value = value;
@@ -99,4 +101,5 @@ namespace ErsatzTV.Application.FFmpegProfiles.Commands
                     return _configElementRepository.Add(ce);
                 });
         }
+    }
 }

ErsatzTV.Core/Domain/ConfigElementKey.cs

@@ -14,5 +14,6 @@
         public static ConfigElementKey FFmpegPreferredLanguageCode => new("ffmpeg.preferred_language_code");
         public static ConfigElementKey SearchIndexVersion => new("search_index.version");
         public static ConfigElementKey HDHRTunerCount => new("hdhr.tuner_count");
+        public static ConfigElementKey CollectionsPageSize => new("pages.collections.page_size");
     }
 }

ErsatzTV.Infrastructure/Data/Repositories/MediaCollectionRepository.cs

@@ -183,7 +183,7 @@ namespace ErsatzTV.Infrastructure.Data.Repositories
                     ORDER BY Name
                     LIMIT {0} OFFSET {1}",
                     pageSize,
-                    (pageNumber - 1) * pageSize)
+                    pageNumber * pageSize)
                 .AsNoTracking()
                 .ToListAsync();
         }

ErsatzTV/Pages/Collections.razor

@@ -1,20 +1,19 @@
 @page "/media/collections"
-@using Microsoft.Extensions.Caching.Memory
-@using Blazored.LocalStorage
+@using ErsatzTV.Application.Configuration.Commands
+@using ErsatzTV.Application.Configuration.Queries
 @using ErsatzTV.Application.MediaCollections
 @using ErsatzTV.Application.MediaCollections.Commands
 @using ErsatzTV.Application.MediaCollections.Queries
 @using ErsatzTV.Application.MediaCards
 @inject IDialogService Dialog
 @inject IMediator Mediator
-@inject IMemoryCache MemoryCache
-@inject ILocalStorageService LocalStorage
 
 <MudContainer MaxWidth="MaxWidth.ExtraLarge" Class="pt-8">
     <MudTable Hover="true"
+              @bind-RowsPerPage="@_rowsPerPage"
               ServerData="@(new Func<TableState, Task<TableData<MediaCollectionViewModel>>>(ServerReload))"
               Dense="true"
-              @ref="                    _table">
+              @ref="_table">
         <ToolBarContent>
             <MudText Typo="Typo.h6">Collections</MudText>
         </ToolBarContent>
@@ -55,11 +54,12 @@
 @code {
     private MudTable<MediaCollectionViewModel> _table;
 
-    protected override async Task OnAfterRenderAsync(bool firstRender)
+    private int _rowsPerPage;
+
+    protected override async Task OnParametersSetAsync()
     {
-        int rowsPerPage = await LocalStorage.GetItemAsync<int?>("pages.collections.rows_per_page") ?? 10;
-        _table.RowsPerPage = rowsPerPage;
-        await _table.ReloadServerData();
+        _rowsPerPage = await Mediator.Send(new GetConfigElementByKey(ConfigElementKey.CollectionsPageSize))
+            .Map(maybeRows => maybeRows.Match(ce => int.TryParse(ce.Value, out int rows) ? rows : 10, () => 10));
     }
 
     private async Task DeleteMediaCollection(MediaCardViewModel vm)
@@ -82,7 +82,7 @@
 
     private async Task<TableData<MediaCollectionViewModel>> ServerReload(TableState state)
     {
-        await LocalStorage.SetItemAsync<int?>("pages.collections.rows_per_page", state.PageSize);
+        await Mediator.Send(new SaveConfigElementByKey(ConfigElementKey.CollectionsPageSize, state.PageSize.ToString()));
 
         PagedMediaCollectionsViewModel data = await Mediator.Send(new GetPagedCollections(state.Page, state.PageSize));
         return new TableData<MediaCollectionViewModel> { TotalItems = data.TotalCount, Items = data.Page };