package mw

import (
	"context"
	"fmt"
	"github.com/OpenIMSDK/Open-IM-Server/pkg/common/log"
	"github.com/OpenIMSDK/Open-IM-Server/pkg/common/mw/specialerror"
	"github.com/OpenIMSDK/Open-IM-Server/pkg/errs"
	"github.com/OpenIMSDK/Open-IM-Server/pkg/proto/wrapperspb"
	"google.golang.org/grpc"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/metadata"
	"google.golang.org/grpc/status"
	"math"
	"runtime/debug"
)

const OperationID = "operationID"
const OpUserID = "opUserID"

func rpcString(v interface{}) string {
	if s, ok := v.(interface{ String() string }); ok {
		return s.String()
	}
	return fmt.Sprintf("%+v", v)
}

func rpcServerInterceptor(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (resp interface{}, err error) {
	var operationID string
	defer func() {
		if r := recover(); r != nil {
			log.ZError(ctx, "rpc panic", nil, "FullMethod", info.FullMethod, "type:", fmt.Sprintf("%T", r), "panic:", r, string(debug.Stack()))
		}
	}()
	funcName := info.FullMethod
	md, ok := metadata.FromIncomingContext(ctx)
	if !ok {
		return nil, status.New(codes.InvalidArgument, "missing metadata").Err()
	}
	if opts := md.Get(OperationID); len(opts) != 1 || opts[0] == "" {
		return nil, status.New(codes.InvalidArgument, "operationID error").Err()
	} else {
		operationID = opts[0]
	}
	var opUserID string
	if opts := md.Get(OpUserID); len(opts) == 1 {
		opUserID = opts[0]
	}
	ctx = context.WithValue(ctx, OperationID, operationID)
	ctx = context.WithValue(ctx, OpUserID, opUserID)
	log.ZInfo(ctx, "rpc server req", "funcName", funcName, "req", rpcString(req))
	resp, err = handler(ctx, req)
	if err == nil {
		log.ZInfo(ctx, "rpc server resp", "funcName", funcName, "resp", rpcString(resp))
		return resp, nil
	}
	unwrap := errs.Unwrap(err)
	codeErr := specialerror.ErrCode(unwrap)
	if codeErr == nil {
		log.ZError(ctx, "rpc InternalServer error", err, "req", req)
		codeErr = errs.ErrInternalServer
	}
	code := codeErr.Code()
	if code <= 0 || code > math.MaxUint32 {
		log.ZError(ctx, "rpc UnknownError", err, "rpc UnknownCode:", code)
		code = errs.ServerInternalError
	}
	grpcStatus := status.New(codes.Code(code), codeErr.Msg())
	if unwrap != err {
		stack := fmt.Sprintf("%+v", err)
		if details, err := grpcStatus.WithDetails(wrapperspb.String(stack)); err == nil {
			grpcStatus = details
		}
	}
	log.ZError(ctx, "rpc server resp", err, "funcName", funcName)
	return nil, grpcStatus.Err()
}

func GrpcServer() grpc.ServerOption {
	return grpc.UnaryInterceptor(rpcServerInterceptor)
}