1 files changed, 61 insertions, 0 deletions
diff --git a/src/SMAPI/IDataHelper.cs b/src/SMAPI/IDataHelper.cs
new file mode 100644
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--- /dev/null
+++ b/src/SMAPI/IDataHelper.cs
@@ -0,0 +1,61 @@
+using System;
+
+namespace StardewModdingAPI
+{
+    /// <summary>Provides an API for reading and storing local mod data.</summary>
+    public interface IDataHelper
+    {
+        /*********
+        ** Public methods
+        *********/
+        /****
+        ** JSON file
+        ****/
+        /// <summary>Read data from a JSON file in the mod's folder.</summary>
+        /// <typeparam name="TModel">The model type. This should be a plain class that has public properties for the data you want. The properties can be complex types.</typeparam>
+        /// <param name="path">The file path relative to the mod folder.</param>
+        /// <returns>Returns the deserialised model, or <c>null</c> if the file doesn't exist or is empty.</returns>
+        /// <exception cref="InvalidOperationException">The <paramref name="path"/> is not relative or contains directory climbing (../).</exception>
+        TModel ReadJsonFile<TModel>(string path) where TModel : class;
+
+        /// <summary>Save data to a JSON file in the mod's folder.</summary>
+        /// <typeparam name="TModel">The model type. This should be a plain class that has public properties for the data you want. The properties can be complex types.</typeparam>
+        /// <param name="path">The file path relative to the mod folder.</param>
+        /// <param name="data">The arbitrary data to save.</param>
+        /// <exception cref="InvalidOperationException">The <paramref name="path"/> is not relative or contains directory climbing (../).</exception>
+        void WriteJsonFile<TModel>(string path, TModel data) where TModel : class;
+
+        /****
+        ** Save file
+        ****/
+        /// <summary>Read arbitrary data stored in the current save slot. This is only possible if a save has been loaded.</summary>
+        /// <typeparam name="TModel">The model type. This should be a plain class that has public properties for the data you want. The properties can be complex types.</typeparam>
+        /// <param name="key">The unique key identifying the data.</param>
+        /// <returns>Returns the parsed data, or <c>null</c> if the entry doesn't exist or is empty.</returns>
+        /// <exception cref="InvalidOperationException">The player hasn't loaded a save file yet.</exception>
+        TModel ReadSaveData<TModel>(string key) where TModel : class;
+
+        /// <summary>Save arbitrary data to the current save slot. This is only possible if a save has been loaded, and the data will be lost if the player exits without saving the current day.</summary>
+        /// <typeparam name="TModel">The model type. This should be a plain class that has public properties for the data you want. The properties can be complex types.</typeparam>
+        /// <param name="key">The unique key identifying the data.</param>
+        /// <param name="data">The arbitrary data to save.</param>
+        /// <exception cref="InvalidOperationException">The player hasn't loaded a save file yet.</exception>
+        void WriteSaveData<TModel>(string key, TModel data) where TModel : class;
+
+
+        /****
+        ** Global app data
+        ****/
+        /// <summary>Read arbitrary data stored on the local computer, synchronised by GOG/Steam if applicable.</summary>
+        /// <typeparam name="TModel">The model type. This should be a plain class that has public properties for the data you want. The properties can be complex types.</typeparam>
+        /// <param name="key">The unique key identifying the data.</param>
+        /// <returns>Returns the parsed data, or <c>null</c> if the entry doesn't exist or is empty.</returns>
+        TModel ReadGlobalData<TModel>(string key) where TModel : class;
+
+        /// <summary>Save arbitrary data to the local computer, synchronised by GOG/Steam if applicable.</summary>
+        /// <typeparam name="TModel">The model type. This should be a plain class that has public properties for the data you want. The properties can be complex types.</typeparam>
+        /// <param name="key">The unique key identifying the data.</param>
+        /// <param name="data">The arbitrary data to save.</param>
+        void WriteGlobalData<TModel>(string key, TModel data) where TModel : class;
+    }
+}