using Mono.Cecil; using Mono.Cecil.Cil; namespace StardewModdingAPI.Framework.ModLoading.Finders { /// <summary>Finds incompatible CIL instructions that reference a given event.</summary> internal class EventFinder : IInstructionHandler { /********* ** Properties *********/ /// <summary>The full type name for which to find references.</summary> private readonly string FullTypeName; /// <summary>The event name for which to find references.</summary> private readonly string EventName; /// <summary>The result to return for matching instructions.</summary> private readonly InstructionHandleResult Result; /********* ** Accessors *********/ /// <summary>A brief noun phrase indicating what the instruction finder matches.</summary> public string NounPhrase { get; } /********* ** Public methods *********/ /// <summary>Construct an instance.</summary> /// <param name="fullTypeName">The full type name for which to find references.</param> /// <param name="eventName">The event name for which to find references.</param> /// <param name="result">The result to return for matching instructions.</param> public EventFinder(string fullTypeName, string eventName, InstructionHandleResult result) { this.FullTypeName = fullTypeName; this.EventName = eventName; this.Result = result; this.NounPhrase = $"{fullTypeName}.{eventName} event"; } /// <summary>Perform the predefined logic for a method if applicable.</summary> /// <param name="module">The assembly module containing the instruction.</param> /// <param name="method">The method definition containing the instruction.</param> /// <param name="assemblyMap">Metadata for mapping assemblies to the current platform.</param> /// <param name="platformChanged">Whether the mod was compiled on a different platform.</param> public virtual InstructionHandleResult Handle(ModuleDefinition module, MethodDefinition method, PlatformAssemblyMap assemblyMap, bool platformChanged) { return InstructionHandleResult.None; } /// <summary>Perform the predefined logic for an instruction if applicable.</summary> /// <param name="module">The assembly module containing the instruction.</param> /// <param name="cil">The CIL processor.</param> /// <param name="instruction">The instruction to handle.</param> /// <param name="assemblyMap">Metadata for mapping assemblies to the current platform.</param> /// <param name="platformChanged">Whether the mod was compiled on a different platform.</param> public virtual InstructionHandleResult Handle(ModuleDefinition module, ILProcessor cil, Instruction instruction, PlatformAssemblyMap assemblyMap, bool platformChanged) { return this.IsMatch(instruction) ? this.Result : InstructionHandleResult.None; } /********* ** Protected methods *********/ /// <summary>Get whether a CIL instruction matches.</summary> /// <param name="instruction">The IL instruction.</param> protected bool IsMatch(Instruction instruction) { MethodReference methodRef = RewriteHelper.AsMethodReference(instruction); return methodRef != null && methodRef.DeclaringType.FullName == this.FullTypeName && (methodRef.Name == "add_" + this.EventName || methodRef.Name == "remove_" + this.EventName); } } }