package middleware

import (
	"context"
	"log/slog"
	"net/http"
	"slices"
	"strings"

	"google.golang.org/grpc"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"

	"github.com/zitadel/zitadel/backend/v3/instrumentation/logging"
	"github.com/zitadel/zitadel/internal/api/call"
)

// LogHandler is a gRPC interceptor that logs the request details
// including protocol, domain, service, HTTP method, path, response code, and duration.
// It depends on [CallDurationHandler] and [RequestDetailsHandler] to set the request start time and ID in the context.
func LogHandler(ignoredMethodSuffixes ...string) grpc.UnaryServerInterceptor {
	return func(ctx context.Context, req any, info *grpc.UnaryServerInfo, next grpc.UnaryHandler) (any, error) {
		if slices.ContainsFunc(ignoredMethodSuffixes, func(s string) bool {
			return strings.HasSuffix(info.FullMethod, s)
		}) {
			return next(ctx, req)
		}
		ctx = logging.NewCtx(ctx, logging.StreamRequest)

		resp, err := next(ctx, req)
		var code codes.Code
		if err != nil {
			code = status.Code(err)
		}
		logging.Info(ctx, "request served",
			slog.String("protocol", "grpc"),
			slog.String("service", serviceFromRPCMethod(info.FullMethod)),
			slog.String("http_method", http.MethodPost), // gRPC always uses POST
			slog.String("path", info.FullMethod),
			slog.Any("code", code),
			slog.Duration("duration", call.Took(ctx)),
		)
		return resp, err
	}
}

func serviceFromRPCMethod(fullMethod string) string {
	parts := strings.Split(fullMethod, "/")
	if len(parts) >= 2 {
		return parts[1]
	}
	return "unknown"
}