// Copyright 2024 Buf Technologies, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package pluginrpc_test

import (
	"context"
	"errors"
	"slices"
	"strconv"
	"testing"

	pluginrpcv1 "buf.build/gen/go/pluginrpc/pluginrpc/protocolbuffers/go/pluginrpc/v1"
	"github.com/stretchr/testify/require"
	"pluginrpc.com/pluginrpc"
	examplev1 "pluginrpc.com/pluginrpc/internal/example/gen/pluginrpc/example/v1"
	"pluginrpc.com/pluginrpc/internal/example/gen/pluginrpc/example/v1/examplev1pluginrpc"
)

const echoPluginProgramName = "echo-plugin"

// We want to append 0 so that we call pluginrpc.ClientWithFormat with the default Format.
var allTestFormats = append(slices.Clone(pluginrpc.AllFormats), 0)

func TestEchoRequest(t *testing.T) {
	t.Parallel()
	forEachDimension(
		t,
		func(t *testing.T, client pluginrpc.Client) {
			echoServiceClient, err := examplev1pluginrpc.NewEchoServiceClient(client)
			require.NoError(t, err)
			response, err := echoServiceClient.EchoRequest(
				context.Background(),
				&examplev1.EchoRequestRequest{
					Message: "hello",
				},
			)
			require.NoError(t, err)
			require.NotNil(t, response)
			require.Equal(t, "hello", response.GetMessage())
		},
	)
}

func TestEchoRequestNil(t *testing.T) {
	t.Parallel()
	forEachDimension(
		t,
		func(t *testing.T, client pluginrpc.Client) {
			echoServiceClient, err := examplev1pluginrpc.NewEchoServiceClient(client)
			require.NoError(t, err)
			response, err := echoServiceClient.EchoRequest(context.Background(), nil)
			require.NoError(t, err)
			require.NotNil(t, response)
			require.Equal(t, "", response.GetMessage())
		},
	)
}

func TestEchoList(t *testing.T) {
	t.Parallel()
	forEachDimension(
		t,
		func(t *testing.T, client pluginrpc.Client) {
			echoServiceClient, err := examplev1pluginrpc.NewEchoServiceClient(client)
			require.NoError(t, err)
			response, err := echoServiceClient.EchoList(context.Background(), nil)
			require.NoError(t, err)
			require.NotNil(t, response)
			require.Equal(t, []string{"foo", "bar"}, response.GetList())
		},
	)
}

func TestEchoError(t *testing.T) {
	t.Parallel()
	forEachDimension(
		t,
		func(t *testing.T, client pluginrpc.Client) {
			echoServiceClient, err := examplev1pluginrpc.NewEchoServiceClient(client)
			require.NoError(t, err)
			_, err = echoServiceClient.EchoError(
				context.Background(),
				&examplev1.EchoErrorRequest{
					Code:    pluginrpcv1.Code_CODE_DEADLINE_EXCEEDED,
					Message: "hello",
				},
			)
			pluginrpcError := &pluginrpc.Error{}
			require.Error(t, err)
			require.ErrorAs(t, err, &pluginrpcError)
			require.Equal(t, pluginrpc.CodeDeadlineExceeded, pluginrpcError.Code())
			unwrappedErr := pluginrpcError.Unwrap()
			require.Error(t, unwrappedErr)
			require.Equal(t, "hello", unwrappedErr.Error())
		},
	)
}

func TestUnimplemented(t *testing.T) {
	t.Parallel()
	forEachDimension(
		t,
		func(t *testing.T, client pluginrpc.Client) {
			err := client.Call(
				context.Background(),
				"/foo/bar",
				nil,
				nil,
			)
			pluginrpcError := &pluginrpc.Error{}
			require.Error(t, err)
			require.ErrorAs(t, err, &pluginrpcError)
			require.Equal(t, pluginrpc.CodeUnimplemented, pluginrpcError.Code())
		},
	)
}

func forEachDimension(t *testing.T, f func(*testing.T, pluginrpc.Client)) {
	for _, format := range allTestFormats {
		for j, newClient := range []func(...pluginrpc.ClientOption) (pluginrpc.Client, error){newExecRunnerClient, newServerRunnerClient} {
			j := j
			format := format
			newClient := newClient
			t.Run(
				format.String()+strconv.Itoa(j),
				func(t *testing.T) {
					t.Parallel()
					client, err := newClient(pluginrpc.ClientWithFormat(format))
					require.NoError(t, err)
					f(t, client)
				},
			)
		}
	}
}

func newExecRunnerClient(clientOptions ...pluginrpc.ClientOption) (pluginrpc.Client, error) {
	return pluginrpc.NewClient(pluginrpc.NewExecRunner(echoPluginProgramName), clientOptions...), nil
}

func newServerRunnerClient(clientOptions ...pluginrpc.ClientOption) (pluginrpc.Client, error) {
	server, err := newServer()
	if err != nil {
		return nil, err
	}
	return pluginrpc.NewClient(pluginrpc.NewServerRunner(server), clientOptions...), nil
}

func newServer() (pluginrpc.Server, error) {
	spec, err := examplev1pluginrpc.EchoServiceSpecBuilder{
		// Note that EchoList does not have a ProcedureBuilder and will default to path being the only arg.
		EchoRequest: []pluginrpc.ProcedureOption{pluginrpc.ProcedureWithArgs("echo", "request")},
		EchoError:   []pluginrpc.ProcedureOption{pluginrpc.ProcedureWithArgs("echo", "error")},
	}.Build()
	if err != nil {
		return nil, err
	}
	serverRegistrar := pluginrpc.NewServerRegistrar()
	handler := pluginrpc.NewHandler(spec)
	echoServiceHandler := newEchoServiceHandler()
	echoServiceServer := examplev1pluginrpc.NewEchoServiceServer(handler, echoServiceHandler)
	examplev1pluginrpc.RegisterEchoServiceServer(serverRegistrar, echoServiceServer)
	return pluginrpc.NewServer(spec, serverRegistrar)
}

type echoServiceHandler struct{}

func newEchoServiceHandler() *echoServiceHandler {
	return &echoServiceHandler{}
}

func (*echoServiceHandler) EchoRequest(
	_ context.Context,
	request *examplev1.EchoRequestRequest,
) (*examplev1.EchoRequestResponse, error) {
	return &examplev1.EchoRequestResponse{
		Message: request.GetMessage(),
	}, nil
}

func (*echoServiceHandler) EchoList(
	context.Context,
	*examplev1.EchoListRequest,
) (*examplev1.EchoListResponse, error) {
	return &examplev1.EchoListResponse{
		List: []string{
			"foo",
			"bar",
		},
	}, nil
}

func (*echoServiceHandler) EchoError(
	_ context.Context,
	request *examplev1.EchoErrorRequest,
) (*examplev1.EchoErrorResponse, error) {
	return nil, pluginrpc.NewError(pluginrpc.Code(request.GetCode()), errors.New(request.GetMessage()))
}