add public mod registry (#220)

6 files changed, 64 insertions, 4 deletions

diff --git a/src/StardewModdingAPI/Framework/ModRegistry.cs b/src/StardewModdingAPI/Framework/ModRegistry.cs
index 51ec7123..209f1928 100644
--- a/src/StardewModdingAPI/Framework/ModRegistry.cs
+++ b/src/StardewModdingAPI/Framework/ModRegistry.cs
@@ -7,7 +7,7 @@ using System.Reflection;
 namespace StardewModdingAPI.Framework
 {
     /// <summary>Tracks the installed mods.</summary>
-    internal class ModRegistry
+    internal class ModRegistry : IModRegistry
     {
         /*********
         ** Properties
@@ -22,6 +22,33 @@ namespace StardewModdingAPI.Framework
         /*********
         ** Public methods
         *********/
+        /****
+        ** IModRegistry
+        ****/
+        /// <summary>Get metadata for all loaded mods.</summary>
+        public IEnumerable<IManifest> GetAll()
+        {
+            return this.Mods.Select(p => p.ModManifest);
+        }
+
+        /// <summary>Get metadata for a loaded mod.</summary>
+        /// <param name="uniqueID">The mod's unique ID.</param>
+        /// <returns>Returns the matching mod's metadata, or <c>null</c> if not found.</returns>
+        public IManifest Get(string uniqueID)
+        {
+            return this.GetAll().FirstOrDefault(p => p.UniqueID == uniqueID);
+        }
+
+        /// <summary>Get whether a mod has been loaded.</summary>
+        /// <param name="uniqueID">The mod's unique ID.</param>
+        public bool IsLoaded(string uniqueID)
+        {
+            return this.GetAll().Any(p => p.UniqueID == uniqueID);
+        }
+
+        /****
+        ** Internal methods
+        ****/
         /// <summary>Register a mod as a possible source of deprecation warnings.</summary>
         /// <param name="mod">The mod instance.</param>
         public void Add(IMod mod)
diff --git a/src/StardewModdingAPI/IModHelper.cs b/src/StardewModdingAPI/IModHelper.cs
index 183b3b2b..02f9c038 100644
--- a/src/StardewModdingAPI/IModHelper.cs
+++ b/src/StardewModdingAPI/IModHelper.cs
@@ -12,6 +12,9 @@
         /// <summary>Simplifies access to private game code.</summary>
         IReflectionHelper Reflection { get; }
 
+        /// <summary>Metadata about loaded mods.</summary>
+        IModRegistry ModRegistry { get; }
+
 
         /*********
         ** Public methods
diff --git a/src/StardewModdingAPI/IModRegistry.cs b/src/StardewModdingAPI/IModRegistry.cs
new file mode 100644
index 00000000..676c9734
--- /dev/null
+++ b/src/StardewModdingAPI/IModRegistry.cs
@@ -0,0 +1,20 @@
+using System.Collections.Generic;
+
+namespace StardewModdingAPI
+{
+    /// <summary>Provides metadata about loaded mods.</summary>
+    public interface IModRegistry
+    {
+        /// <summary>Get metadata for all loaded mods.</summary>
+        IEnumerable<IManifest> GetAll();
+
+        /// <summary>Get metadata for a loaded mod.</summary>
+        /// <param name="uniqueID">The mod's unique ID.</param>
+        /// <returns>Returns the matching mod's metadata, or <c>null</c> if not found.</returns>
+        IManifest Get(string uniqueID);
+
+        /// <summary>Get whether a mod has been loaded.</summary>
+        /// <param name="uniqueID">The mod's unique ID.</param>
+        bool IsLoaded(string uniqueID);
+    }
+}
\ No newline at end of file
diff --git a/src/StardewModdingAPI/ModHelper.cs b/src/StardewModdingAPI/ModHelper.cs
index 78b3eefa..c20130cf 100644
--- a/src/StardewModdingAPI/ModHelper.cs
+++ b/src/StardewModdingAPI/ModHelper.cs
@@ -30,22 +30,31 @@ namespace StardewModdingAPI
         /// <summary>Simplifies access to private game code.</summary>
         public IReflectionHelper Reflection { get; } = new ReflectionHelper();
 
+        /// <summary>Metadata about loaded mods.</summary>
+        public IModRegistry ModRegistry { get; }
+
 
         /*********
         ** Public methods
         *********/
         /// <summary>Construct an instance.</summary>
         /// <param name="modDirectory">The mod directory path.</param>
-        public ModHelper(string modDirectory)
+        /// <param name="modRegistry">Metadata about loaded mods.</param>
+        /// <exception cref="ArgumentException">An argument is null or invalid.</exception>
+        /// <exception cref="InvalidOperationException">The <paramref name="modDirectory"/> path does not exist on disk.</exception>
+        public ModHelper(string modDirectory, IModRegistry modRegistry)
         {
             // validate
+            if (modRegistry == null)
+                throw new ArgumentException("The mod registry cannot be null.");
             if (string.IsNullOrWhiteSpace(modDirectory))
-                throw new InvalidOperationException("The mod directory cannot be empty.");
+                throw new ArgumentException("The mod directory cannot be empty.");
             if (!Directory.Exists(modDirectory))
                 throw new InvalidOperationException("The specified mod directory does not exist.");
 
             // initialise
             this.DirectoryPath = modDirectory;
+            this.ModRegistry = modRegistry;
         }
 
         /****
diff --git a/src/StardewModdingAPI/Program.cs b/src/StardewModdingAPI/Program.cs
index 11578fc4..29f71cb7 100644
--- a/src/StardewModdingAPI/Program.cs
+++ b/src/StardewModdingAPI/Program.cs
@@ -353,7 +353,7 @@ namespace StardewModdingAPI
                 }
 
                 // get helper
-                IModHelper helper = new ModHelper(directory);
+                IModHelper helper = new ModHelper(directory, Program.ModRegistry);
 
                 // get manifest path
                 string manifestPath = Path.Combine(directory, "manifest.json");
diff --git a/src/StardewModdingAPI/StardewModdingAPI.csproj b/src/StardewModdingAPI/StardewModdingAPI.csproj
index 125f287e..d56b6866 100644
--- a/src/StardewModdingAPI/StardewModdingAPI.csproj
+++ b/src/StardewModdingAPI/StardewModdingAPI.csproj
@@ -148,6 +148,7 @@
     <Compile Include="Events\EventArgsStringChanged.cs" />
     <Compile Include="Events\GameEvents.cs" />
     <Compile Include="Events\GraphicsEvents.cs" />
+    <Compile Include="IModRegistry.cs" />
     <Compile Include="Events\LocationEvents.cs" />
     <Compile Include="Events\MenuEvents.cs" />
     <Compile Include="Events\MineEvents.cs" />