1 files changed, 165 insertions, 0 deletions
diff --git a/src/StardewModdingAPI/Constants.cs b/src/StardewModdingAPI/Constants.cs
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+++ b/src/StardewModdingAPI/Constants.cs
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+using System;
+using System.IO;
+using System.Linq;
+using System.Reflection;
+using StardewModdingAPI.Framework;
+using StardewModdingAPI.Framework.ModLoading;
+using StardewValley;
+
+namespace StardewModdingAPI
+{
+    /// <summary>Contains SMAPI's constants and assumptions.</summary>
+    public static class Constants
+    {
+        /*********
+        ** Properties
+        *********/
+        /// <summary>The directory path containing the current save's data (if a save is loaded).</summary>
+        private static string RawSavePath => Context.IsSaveLoaded ? Path.Combine(Constants.SavesPath, Constants.GetSaveFolderName()) : null;
+
+        /// <summary>Whether the directory containing the current save's data exists on disk.</summary>
+        private static bool SavePathReady => Context.IsSaveLoaded && Directory.Exists(Constants.RawSavePath);
+
+
+        /*********
+        ** Accessors
+        *********/
+        /****
+        ** Public
+        ****/
+        /// <summary>SMAPI's current semantic version.</summary>
+        public static ISemanticVersion ApiVersion { get; } =
+#if SMAPI_1_x
+            new SemanticVersion(1, 15, 4);
+#else
+            new SemanticVersion(2, 0, 0, $"alpha-{DateTime.UtcNow:yyyyMMddHHmm}");
+#endif
+
+        /// <summary>The minimum supported version of Stardew Valley.</summary>
+        public static ISemanticVersion MinimumGameVersion { get; } = new SemanticVersion("1.2.30");
+
+        /// <summary>The maximum supported version of Stardew Valley.</summary>
+        public static ISemanticVersion MaximumGameVersion { get; } = null;
+
+        /// <summary>The path to the game folder.</summary>
+        public static string ExecutionPath { get; } = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
+
+        /// <summary>The directory path containing Stardew Valley's app data.</summary>
+        public static string DataPath { get; } = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "StardewValley");
+
+        /// <summary>The directory path in which error logs should be stored.</summary>
+        public static string LogDir { get; } = Path.Combine(Constants.DataPath, "ErrorLogs");
+
+        /// <summary>The directory path where all saves are stored.</summary>
+        public static string SavesPath { get; } = Path.Combine(Constants.DataPath, "Saves");
+
+        /// <summary>The directory name containing the current save's data (if a save is loaded and the directory exists).</summary>
+        public static string SaveFolderName => Context.IsSaveLoaded ? Constants.GetSaveFolderName() : "";
+
+        /// <summary>The directory path containing the current save's data (if a save is loaded and the directory exists).</summary>
+        public static string CurrentSavePath => Constants.SavePathReady ? Path.Combine(Constants.SavesPath, Constants.GetSaveFolderName()) : "";
+
+        /****
+        ** Internal
+        ****/
+        /// <summary>The GitHub repository to check for updates.</summary>
+        internal const string GitHubRepository = "Pathoschild/SMAPI";
+
+        /// <summary>The file path for the SMAPI configuration file.</summary>
+        internal static string ApiConfigPath => Path.Combine(Constants.ExecutionPath, $"{typeof(Program).Assembly.GetName().Name}.config.json");
+
+        /// <summary>The file path to the log where the latest output should be saved.</summary>
+        internal static string DefaultLogPath => Path.Combine(Constants.LogDir, "SMAPI-latest.txt");
+
+        /// <summary>A copy of the log leading up to the previous fatal crash, if any.</summary>
+        internal static string FatalCrashLog => Path.Combine(Constants.LogDir, "SMAPI-crash.txt");
+
+        /// <summary>The file path which stores a fatal crash message for the next run.</summary>
+        internal static string FatalCrashMarker => Path.Combine(Constants.ExecutionPath, "StardewModdingAPI.crash.marker");
+
+        /// <summary>The full path to the folder containing mods.</summary>
+        internal static string ModPath { get; } = Path.Combine(Constants.ExecutionPath, "Mods");
+
+        /// <summary>The game's current semantic version.</summary>
+        internal static ISemanticVersion GameVersion { get; } = new GameVersion(Constants.GetGameVersion());
+
+        /// <summary>The target game platform.</summary>
+        internal static Platform TargetPlatform { get; } =
+#if SMAPI_FOR_WINDOWS
+        Platform.Windows;
+#else
+        Platform.Mono;
+#endif
+
+
+        /*********
+        ** Internal methods
+        *********/
+        /// <summary>Get metadata for mapping assemblies to the current platform.</summary>
+        /// <param name="targetPlatform">The target game platform.</param>
+        internal static PlatformAssemblyMap GetAssemblyMap(Platform targetPlatform)
+        {
+            // get assembly changes needed for platform
+            string[] removeAssemblyReferences;
+            Assembly[] targetAssemblies;
+            switch (targetPlatform)
+            {
+                case Platform.Mono:
+                    removeAssemblyReferences = new[]
+                    {
+                        "Stardew Valley",
+                        "Microsoft.Xna.Framework",
+                        "Microsoft.Xna.Framework.Game",
+                        "Microsoft.Xna.Framework.Graphics"
+                    };
+                    targetAssemblies = new[]
+                    {
+                        typeof(StardewValley.Game1).Assembly,
+                        typeof(Microsoft.Xna.Framework.Vector2).Assembly
+                    };
+                    break;
+
+                case Platform.Windows:
+                    removeAssemblyReferences = new[]
+                    {
+                        "StardewValley",
+                        "MonoGame.Framework"
+                    };
+                    targetAssemblies = new[]
+                    {
+                        typeof(StardewValley.Game1).Assembly,
+                        typeof(Microsoft.Xna.Framework.Vector2).Assembly,
+                        typeof(Microsoft.Xna.Framework.Game).Assembly,
+                        typeof(Microsoft.Xna.Framework.Graphics.SpriteBatch).Assembly
+                    };
+                    break;
+
+                default:
+                    throw new InvalidOperationException($"Unknown target platform '{targetPlatform}'.");
+            }
+
+            return new PlatformAssemblyMap(targetPlatform, removeAssemblyReferences, targetAssemblies);
+        }
+
+
+        /*********
+        ** Private methods
+        *********/
+        /// <summary>Get the name of a save directory for the current player.</summary>
+        private static string GetSaveFolderName()
+        {
+            string prefix = new string(Game1.player.name.Where(char.IsLetterOrDigit).ToArray());
+            return $"{prefix}_{Game1.uniqueIDForThisGame}";
+        }
+
+        /// <summary>Get the game's current version string.</summary>
+        private static string GetGameVersion()
+        {
+            // we need reflection because it's a constant, so SMAPI's references to it are inlined at compile-time
+            FieldInfo field = typeof(Game1).GetField(nameof(Game1.version), BindingFlags.Public | BindingFlags.Static);
+            if (field == null)
+                throw new InvalidOperationException($"The {nameof(Game1)}.{nameof(Game1.version)} field could not be found.");
+            return (string)field.GetValue(null);
+        }
+    }
+}