using Mono.Cecil; using Mono.Cecil.Cil; namespace StardewModdingAPI.Framework.ModLoading.Finders { /// Finds incompatible CIL instructions that reference a given event and throws an . internal class EventFinder : IInstructionRewriter { /********* ** Properties *********/ /// The full type name for which to find references. private readonly string FullTypeName; /// The event name for which to find references. private readonly string EventName; /********* ** Accessors *********/ /// A brief noun phrase indicating what the instruction finder matches. public string NounPhrase { get; } /********* ** Public methods *********/ /// Construct an instance. /// The full type name for which to find references. /// The event name for which to find references. /// A brief noun phrase indicating what the instruction finder matches (or null to generate one). public EventFinder(string fullTypeName, string eventName, string nounPhrase = null) { this.FullTypeName = fullTypeName; this.EventName = eventName; this.NounPhrase = nounPhrase ?? $"{fullTypeName}.{eventName} event"; } /// Rewrite a method definition for compatibility. /// The mod to which the module belongs. /// The module being rewritten. /// The method definition to rewrite. /// Metadata for mapping assemblies to the current platform. /// Whether the mod was compiled on a different platform. /// Returns whether the instruction was rewritten. /// The CIL instruction is not compatible, and can't be rewritten. public virtual bool Rewrite(IModMetadata mod, ModuleDefinition module, MethodDefinition method, PlatformAssemblyMap assemblyMap, bool platformChanged) { return false; } /// Rewrite a CIL instruction for compatibility. /// The mod to which the module belongs. /// The module being rewritten. /// The CIL rewriter. /// The instruction to rewrite. /// Metadata for mapping assemblies to the current platform. /// Whether the mod was compiled on a different platform. /// Returns whether the instruction was rewritten. /// The CIL instruction is not compatible, and can't be rewritten. public virtual bool Rewrite(IModMetadata mod, ModuleDefinition module, ILProcessor cil, Instruction instruction, PlatformAssemblyMap assemblyMap, bool platformChanged) { if (!this.IsMatch(instruction)) return false; throw new IncompatibleInstructionException(this.NounPhrase); } /********* ** Protected methods *********/ /// Get whether a CIL instruction matches. /// The IL instruction. 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); } } }