package client

import (
	"context"
	"fmt"

	"golang.conradwood.net/go-easyops/auth"
	"golang.conradwood.net/go-easyops/cmdline"
	"golang.conradwood.net/go-easyops/common"
	"golang.conradwood.net/go-easyops/ctx"
	pctx "golang.conradwood.net/go-easyops/ctx"
	"golang.conradwood.net/go-easyops/ctx/shared"
	pp "golang.conradwood.net/go-easyops/profiling"
	"golang.conradwood.net/go-easyops/prometheus"
	"golang.conradwood.net/go-easyops/rpc"
	"golang.conradwood.net/go-easyops/tokens"
	"golang.conradwood.net/go-easyops/utils"

	//	"reflect"
	"google.golang.org/grpc"
	//	"google.golang.org/grpc/metadata"
	"time"
)

// called for each outbound rpc
func ClientMetricsUnaryInterceptor(ctx context.Context, method string, req, reply interface{}, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
	if ctx == nil {
		return fmt.Errorf("missing context, will not make outbound call without context")
	}
	pp.ClientRpcEntered()
	defer pp.ClientRpcDone()
	start := time.Now()
	s, m, err := splitMethodAndService(method)
	// keep prometheus happy: (not to panic)
	if s == "" {
		s = "unknown"
	}
	if m == "" {
		m = "unknown"
	}
	// bad programmer! - log it prominently (often)
	if err != nil {
		fmt.Printf("[go-easyops] invalid fqdn method: \"%s\": %s\n", method, err)
	}
	if cmdline.IsDebugRPCClient() && !isKnownNotAuthRPCs(s, m) {
		ls := pctx.GetLocalState(ctx)
		// technically.. this is _wrong_. the CallingService() is the service which called us.
		if ls.CallingService() == nil && ls.User() == nil {
			utils.PrintStack("[go-easyops] outbound context issue")
			fmt.Printf("[go-easyops] WARNING calling another service (%s.%s) with a context without authentication (%s)\n", s, m, pctx.Context2String(ctx))
		} else if ls.CallingService() == nil && tokens.GetServiceTokenParameter() != "" {
			utils.PrintStack("[go-easyops] outbound context issue")
			fmt.Printf("[go-easyops] WARNING calling another service (%s.%s) with a context without calling service information (%s)\n", s, m, pctx.Context2String(ctx))
		}
		/*
			_, ex := metadata.FromOutgoingContext(ctx)
			if !ex {
				if *debug_rpc_client {
					fmt.Printf("Context: %#v\n", ctx)
					utils.PrintStack("No metadata:")
				}
				fmt.Printf("[go-easyops] WARNING - calling external method %s.%s without metadata (authentication)\n", s, m)
			}
		*/
	}

	print_debug_client(ctx, fmt.Sprintf("%s.%s()", s, m))

	grpc_client_sent.With(prometheus.Labels{"method": m, "servicename": s}).Inc()

	// generated by gRPC, calls the gRPC method
	err = invoker(ctx, method, req, reply, cc, opts...)

	observeRPC(start, s, m) // record time.Since(start) into metric

	dur := time.Since(start)
	if err != nil {
		grpc_client_failed.With(prometheus.Labels{"method": m, "servicename": s}).Inc()
		if *dialer_debug || cmdline.IsDebugRPCClient() {
			fmt.Printf("Invoked remote method=%s duration=%0.2fs error=%v (Method: \"%s\" in Service: \"%s\")\n", method, dur.Seconds(), err, m, s)
			utils.PrintStack("method %s/%s invoked at:\n", s, m)
		}
	} else if cmdline.IsDebugRPCClient() {
		fmt.Printf("Invoked method %s.%s (%0.2fs)...\n", s, m, dur.Seconds())
	}

	return err
}
func print_debug_client(ictx context.Context, targetname string) {
	if !*dialer_debug && !cmdline.IsDebugRPCClient() {
		return
	}
	if cmdline.ContextWithBuilder() {
		ls := ctx.GetLocalState(ictx)
		/*
			if ls == nil || ls.CallingService() == nil && strings.Contains(targetname, "Mail") {
				panic("no calling service")
			}
		*/
		us := auth.UserIDString(common.VerifySignedUser(ls.User()))
		sv := auth.UserIDString(common.VerifySignedUser(ls.CallingService()))
		cmdline.DebugfContext("Invoking method %s as %s (service %s)...\n", targetname, us, sv)
		cmdline.DebugfContext("Outbound context:\n")
		cmdline.DebugfContext("Loccalstate: %s\n", shared.LocalState2string(ls))

		return
	}
	cs := rpc.CallStateFromContext(ictx)
	if cs == nil {
		//		utils.PrintStack("no callstate")
		fmt.Printf("[go-easyops] WARNING - calling external method %s without callstate (%s)\n", targetname, utils.CallingFunction())
	} else {
		//		cs.PrintContext()
		us := "none"
		u := cs.User()
		if u != nil {
			us = fmt.Sprintf("UserID=%s, Email=%s", u.ID, u.Email)
		}
		fmt.Printf("Invoking method as %s...%s\n", targetname, us)
	}
	//fmt.Printf("Contype: %s (%T)\n", reflect.TypeOf(cc), cc)
	//		fmt.Printf("Ctx: %#v\n", ctx)

}