feature: favorite illusts

Pixiview/Utils/Stores.cs

@@ -5,6 +5,7 @@ using System.Net;
 using System.Net.Http;
 using System.Text;
 using Newtonsoft.Json;
+using Pixiview.Illust;
 using Xamarin.Essentials;
 using Xamarin.Forms;
 
@@ -14,12 +15,17 @@ namespace Pixiview.Utils
     {
         public static readonly string PersonalFolder = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
         public static readonly string CacheFolder = Environment.GetFolderPath(Environment.SpecialFolder.InternetCache);
+
         private const string pagesFolder = "pages";
         private const string imageFolder = "img-original";
         private const string previewFolder = "img-master";
         private const string thumbFolder = "img-thumb";
         private const string userFolder = "user-profile";
+
         private const string illustFile = "illust.json";
+        private const string favoriteFile = "favorites.json";
+
+        private static readonly object sync = new object();
 
         public static bool NetworkAvailable
         {
@@ -87,6 +93,64 @@ namespace Pixiview.Utils
             }
         }
 
+        private static T ReadObject<T>(string file)
+        {
+            string content = null;
+            if (File.Exists(file))
+            {
+                try
+                {
+                    content = File.ReadAllText(file);
+                }
+                catch (Exception ex)
+                {
+                    App.DebugError("read", $"failed to read file: {file}, error: {ex.Message}");
+                }
+            }
+            else
+            {
+                App.DebugError("read", $"file not found: {file}");
+                return default;
+            }
+            try
+            {
+                return JsonConvert.DeserializeObject<T>(content);
+            }
+            catch (Exception ex)
+            {
+                App.DebugError("read", $"failed to parse illust JSON object, error: {ex.Message}");
+                return default;
+            }
+        }
+
+        private static void WriteObject(string file, object obj)
+        {
+            var dir = Path.GetDirectoryName(file);
+            if (!Directory.Exists(dir))
+            {
+                Directory.CreateDirectory(dir);
+            }
+            string content;
+            try
+            {
+                content = JsonConvert.SerializeObject(obj, Formatting.None);
+            }
+            catch (Exception ex)
+            {
+                App.DebugError("write", $"failed to serialize object, error: {ex.Message}");
+                return;
+            }
+
+            try
+            {
+                File.WriteAllText(file, content, Encoding.UTF8);
+            }
+            catch (Exception ex)
+            {
+                App.DebugError("write", $"failed to write file: {file}, error: {ex.Message}");
+            }
+        }
+
         public static IllustData LoadIllustData(bool force = false)
         {
             var file = Path.Combine(PersonalFolder, illustFile);
@@ -118,6 +182,21 @@ namespace Pixiview.Utils
             return result;
         }
 
+        public static IllustFavorite LoadFavoritesIllusts()
+        {
+            var file = Path.Combine(PersonalFolder, favoriteFile);
+            return ReadObject<IllustFavorite>(file);
+        }
+
+        public static void SaveFavoritesIllusts(IllustFavorite data)
+        {
+            var file = Path.Combine(PersonalFolder, favoriteFile);
+            lock (sync)
+            {
+                WriteObject(file, data);
+            }
+        }
+
         public static ImageSource LoadIllustImage(string url)
         {
             return LoadImage(url, PersonalFolder, imageFolder);
@@ -306,6 +385,7 @@ namespace Pixiview.Utils
         public const string Recommends = "recommends";
         public const string ByUser = "byuser";
         public const string Ranking = "ranking";
+        public const string Favorites = "favorites";
         public const string Option = "option";
     }
 }