1 files changed, 163 insertions, 0 deletions
diff --git a/src/Jellyfin.LiveTv/EmbyTV/ItemDataProvider.cs b/src/Jellyfin.LiveTv/EmbyTV/ItemDataProvider.cs
new file mode 100644
index 000000000..547ffeb66
--- /dev/null
+++ b/src/Jellyfin.LiveTv/EmbyTV/ItemDataProvider.cs
@@ -0,0 +1,163 @@
+#pragma warning disable CS1591
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.IO;
+using System.Linq;
+using System.Text.Json;
+using Jellyfin.Extensions.Json;
+using Microsoft.Extensions.Logging;
+
+namespace Jellyfin.LiveTv.EmbyTV
+{
+    public class ItemDataProvider<T>
+        where T : class
+    {
+        private readonly string _dataPath;
+        private readonly object _fileDataLock = new object();
+        private readonly JsonSerializerOptions _jsonOptions = JsonDefaults.Options;
+        private T[]? _items;
+
+        public ItemDataProvider(
+            ILogger logger,
+            string dataPath,
+            Func<T, T, bool> equalityComparer)
+        {
+            Logger = logger;
+            _dataPath = dataPath;
+            EqualityComparer = equalityComparer;
+        }
+
+        protected ILogger Logger { get; }
+
+        protected Func<T, T, bool> EqualityComparer { get; }
+
+        [MemberNotNull(nameof(_items))]
+        private void EnsureLoaded()
+        {
+            if (_items is not null)
+            {
+                return;
+            }
+
+            if (File.Exists(_dataPath))
+            {
+                Logger.LogInformation("Loading live tv data from {Path}", _dataPath);
+
+                try
+                {
+                    var bytes = File.ReadAllBytes(_dataPath);
+                    _items = JsonSerializer.Deserialize<T[]>(bytes, _jsonOptions);
+                    if (_items is null)
+                    {
+                        Logger.LogError("Error deserializing {Path}, data was null", _dataPath);
+                        _items = Array.Empty<T>();
+                    }
+
+                    return;
+                }
+                catch (JsonException ex)
+                {
+                    Logger.LogError(ex, "Error deserializing {Path}", _dataPath);
+                }
+            }
+
+            _items = Array.Empty<T>();
+        }
+
+        private void SaveList()
+        {
+            Directory.CreateDirectory(Path.GetDirectoryName(_dataPath) ?? throw new ArgumentException("Path can't be a root directory.", nameof(_dataPath)));
+            var jsonString = JsonSerializer.Serialize(_items, _jsonOptions);
+            File.WriteAllText(_dataPath, jsonString);
+        }
+
+        public IReadOnlyList<T> GetAll()
+        {
+            lock (_fileDataLock)
+            {
+                EnsureLoaded();
+                return (T[])_items.Clone();
+            }
+        }
+
+        public virtual void Update(T item)
+        {
+            ArgumentNullException.ThrowIfNull(item);
+
+            lock (_fileDataLock)
+            {
+                EnsureLoaded();
+
+                var index = Array.FindIndex(_items, i => EqualityComparer(i, item));
+                if (index == -1)
+                {
+                    throw new ArgumentException("item not found");
+                }
+
+                _items[index] = item;
+
+                SaveList();
+            }
+        }
+
+        public virtual void Add(T item)
+        {
+            ArgumentNullException.ThrowIfNull(item);
+
+            lock (_fileDataLock)
+            {
+                EnsureLoaded();
+
+                if (_items.Any(i => EqualityComparer(i, item)))
+                {
+                    throw new ArgumentException("item already exists", nameof(item));
+                }
+
+                int oldLen = _items.Length;
+                var newList = new T[oldLen + 1];
+                _items.CopyTo(newList, 0);
+                newList[oldLen] = item;
+                _items = newList;
+
+                SaveList();
+            }
+        }
+
+        public virtual void AddOrUpdate(T item)
+        {
+            lock (_fileDataLock)
+            {
+                EnsureLoaded();
+
+                int index = Array.FindIndex(_items, i => EqualityComparer(i, item));
+                if (index == -1)
+                {
+                    int oldLen = _items.Length;
+                    var newList = new T[oldLen + 1];
+                    _items.CopyTo(newList, 0);
+                    newList[oldLen] = item;
+                    _items = newList;
+                }
+                else
+                {
+                    _items[index] = item;
+                }
+
+                SaveList();
+            }
+        }
+
+        public virtual void Delete(T item)
+        {
+            lock (_fileDataLock)
+            {
+                EnsureLoaded();
+                _items = _items.Where(i => !EqualityComparer(i, item)).ToArray();
+
+                SaveList();
+            }
+        }
+    }
+}