package wasmguest

import (
	"encoding/json"
	"testing"

	"git.dev.alexdunmow.com/block/pluginsdk/rbac"
	"google.golang.org/protobuf/proto"
	"google.golang.org/protobuf/reflect/protodesc"
	"google.golang.org/protobuf/reflect/protoregistry"
	"google.golang.org/protobuf/types/descriptorpb"
	_ "google.golang.org/protobuf/types/known/timestamppb"
)

func TestCaptureMCPToolsUsesCompiledProtobufDescriptor(t *testing.T) {
	registerMCPFixture(t)
	procedure := "/mcpfixture.v1.WikiService/ListArticles"
	tools := captureMCPTools(map[string]rbac.Role{procedure: rbac.RoleAdmin})
	if len(tools) != 1 {
		t.Fatalf("captureMCPTools() returned %d tools, want 1", len(tools))
	}
	tool := tools[0]
	if tool.GetProcedure() != procedure || tool.GetServiceFullName() != "mcpfixture.v1.WikiService" || tool.GetMethodName() != "ListArticles" {
		t.Fatalf("unexpected procedure metadata: %#v", tool)
	}
	if tool.GetDescription() != "Lists Wiki articles." || tool.GetDocumentation() != "ListArticles lists Wiki articles.\n\nSupports pagination." {
		t.Fatalf("unexpected descriptor documentation: description=%q doc=%q", tool.GetDescription(), tool.GetDocumentation())
	}
	var schema map[string]any
	if err := json.Unmarshal(tool.GetInputSchemaJson(), &schema); err != nil {
		t.Fatalf("schema is not JSON: %v", err)
	}
	properties, ok := schema["properties"].(map[string]any)
	if !ok {
		t.Fatalf("schema properties = %#v", schema["properties"])
	}
	assertSchemaType(t, properties, "search", "string")
	assertSchemaType(t, properties, "page", "integer")
	assertSchemaType(t, properties, "published_after", "string")
}

func TestCaptureMCPToolsSkipsUnresolvableAndStreamingProcedures(t *testing.T) {
	registerMCPFixture(t)
	tools := captureMCPTools(map[string]rbac.Role{
		"/mcpfixture.v1.WikiService/StreamArticles": rbac.RoleAdmin,
		"/missing.v1.WikiService/ListArticles":      rbac.RoleAdmin,
		"not-a-procedure":                           rbac.RoleAdmin,
	})
	if len(tools) != 0 {
		t.Fatalf("captureMCPTools() returned %d tools, want fail-closed omission", len(tools))
	}
}

func assertSchemaType(t *testing.T, properties map[string]any, field, expected string) {
	t.Helper()
	property, ok := properties[field].(map[string]any)
	if !ok || property["type"] != expected {
		t.Fatalf("schema field %q = %#v, want type %q", field, properties[field], expected)
	}
}

func registerMCPFixture(t *testing.T) {
	t.Helper()
	if _, err := protoregistry.GlobalFiles.FindFileByPath("test/mcpfixture.proto"); err == nil {
		return
	}
	file, err := protodesc.NewFile(&descriptorpb.FileDescriptorProto{
		Name:       new("test/mcpfixture.proto"),
		Package:    new("mcpfixture.v1"),
		Syntax:     new("proto3"),
		Dependency: []string{"google/protobuf/timestamp.proto"},
		MessageType: []*descriptorpb.DescriptorProto{{
			Name: new("ListArticlesRequest"),
			Field: []*descriptorpb.FieldDescriptorProto{
				{Name: new("search"), Number: proto.Int32(1), Label: descriptorpb.FieldDescriptorProto_LABEL_OPTIONAL.Enum(), Type: descriptorpb.FieldDescriptorProto_TYPE_STRING.Enum()},
				{Name: new("page"), Number: proto.Int32(2), Label: descriptorpb.FieldDescriptorProto_LABEL_OPTIONAL.Enum(), Type: descriptorpb.FieldDescriptorProto_TYPE_INT32.Enum()},
				{Name: new("published_after"), Number: proto.Int32(3), Label: descriptorpb.FieldDescriptorProto_LABEL_OPTIONAL.Enum(), Type: descriptorpb.FieldDescriptorProto_TYPE_MESSAGE.Enum(), TypeName: new(".google.protobuf.Timestamp")},
			},
		}, {
			Name: new("ListArticlesResponse"),
		}},
		Service: []*descriptorpb.ServiceDescriptorProto{{
			Name: new("WikiService"),
			Method: []*descriptorpb.MethodDescriptorProto{{
				Name: new("ListArticles"), InputType: new(".mcpfixture.v1.ListArticlesRequest"), OutputType: new(".mcpfixture.v1.ListArticlesResponse"),
			}, {
				Name: new("StreamArticles"), InputType: new(".mcpfixture.v1.ListArticlesRequest"), OutputType: new(".mcpfixture.v1.ListArticlesResponse"), ServerStreaming: new(true),
			}},
		}},
		SourceCodeInfo: &descriptorpb.SourceCodeInfo{Location: []*descriptorpb.SourceCodeInfo_Location{{
			Path: []int32{6, 0, 2, 0}, Span: []int32{1, 0, 1, 1}, LeadingComments: new("ListArticles lists Wiki articles.\n\nSupports pagination."),
		}}},
	}, protoregistry.GlobalFiles)
	if err != nil {
		t.Fatalf("create fixture descriptor: %v", err)
	}
	if err := protoregistry.GlobalFiles.RegisterFile(file); err != nil {
		t.Fatalf("register fixture descriptor: %v", err)
	}
}