using System; using System.Linq; using System.Reflection; using Mono.Cecil; using Mono.Cecil.Cil; namespace StardewModdingAPI.Framework.ModLoading { /// <summary>Provides helper methods for field rewriters.</summary> internal static class RewriteHelper { /********* ** Public methods *********/ /// <summary>Get the field reference from an instruction if it matches.</summary> /// <param name="instruction">The IL instruction.</param> public static FieldReference AsFieldReference(Instruction instruction) { return instruction.OpCode == OpCodes.Ldfld || instruction.OpCode == OpCodes.Ldsfld || instruction.OpCode == OpCodes.Stfld || instruction.OpCode == OpCodes.Stsfld ? (FieldReference)instruction.Operand : null; } /// <summary>Get the method reference from an instruction if it matches.</summary> /// <param name="instruction">The IL instruction.</param> public static MethodReference AsMethodReference(Instruction instruction) { return instruction.OpCode == OpCodes.Call || instruction.OpCode == OpCodes.Callvirt ? (MethodReference)instruction.Operand : null; } /// <summary>Get whether a type matches a type reference.</summary> /// <param name="type">The defined type.</param> /// <param name="reference">The type reference.</param> public static bool IsSameType(Type type, TypeReference reference) { // same namespace & name if (type.Namespace != reference.Namespace || type.Name != reference.Name) return false; // same generic parameters if (type.IsGenericType) { if (!reference.IsGenericInstance) return false; Type[] defGenerics = type.GetGenericArguments(); TypeReference[] refGenerics = ((GenericInstanceType)reference).GenericArguments.ToArray(); if (defGenerics.Length != refGenerics.Length) return false; for (int i = 0; i < defGenerics.Length; i++) { if (!RewriteHelper.IsSameType(defGenerics[i], refGenerics[i])) return false; } } return true; } /// <summary>Get whether a method definition matches the signature expected by a method reference.</summary> /// <param name="definition">The method definition.</param> /// <param name="reference">The method reference.</param> public static bool HasMatchingSignature(MethodInfo definition, MethodReference reference) { // same name if (definition.Name != reference.Name) return false; // same arguments ParameterInfo[] definitionParameters = definition.GetParameters(); ParameterDefinition[] referenceParameters = reference.Parameters.ToArray(); if (referenceParameters.Length != definitionParameters.Length) return false; for (int i = 0; i < referenceParameters.Length; i++) { if (!RewriteHelper.IsSameType(definitionParameters[i].ParameterType, referenceParameters[i].ParameterType)) return false; } return true; } /// <summary>Get whether a type has a method whose signature matches the one expected by a method reference.</summary> /// <param name="type">The type to check.</param> /// <param name="reference">The method reference.</param> public static bool HasMatchingSignature(Type type, MethodReference reference) { return type .GetMethods(BindingFlags.Instance | BindingFlags.DeclaredOnly | BindingFlags.Public) .Any(method => RewriteHelper.HasMatchingSignature(method, reference)); } } }