package runtime

import (
	"encoding/json"
	"testing"
	"time"

	"github.com/nats-io/nats.go"

	"github.com/novox/mesh-tools/node-tools/internal/bus"
	mt "github.com/novox/mesh-tools/node-tools/internal/meshtest"
)

type saidCaller struct {
	Caller    string         `json:"caller"`
	Arguments map[string]any `json:"arguments"`
}

// **A module is told who called it, from the subject the call arrived on** (novox/hq issue 365): a call on the
// caller-named subject reaches the bundle with that caller in the call's `_meta`, for a module's tool, on its
// machine's address, and for a seat's verb; a caller named in the arguments is only an argument.
func TestACallOnTheCallerNamedSubjectReachesTheModuleWithItsCaller(t *testing.T) {
	mesh := mt.New(t)
	mesh.Issue(t, mt.MembershipOf("ledger", "anchor", true, map[string][]string{"node-desk": {"who"}}))
	nodeTools := connect(t, "node-tools", "anchor")
	stop, err := Run(nodeTools, []Served{{"ledger", []string{mt.Fixture("caller-echo.py")}}}, nil, func(string, ...any) {})
	if err != nil {
		t.Fatal(err)
	}
	defer stop()
	asker, err := bus.Connect(bus.Credential{URL: mt.URL(t), Module: "node-tools", Node: "shanks",
		User: "shanks.node-tools", Password: "unused"})
	if err != nil {
		t.Fatal(err)
	}
	asker.Logf = func(string, ...any) {}
	defer asker.Close()

	for _, key := range []string{"ledger.who", "ledger.who@anchor", "seat:node-desk.who@anchor"} {
		var got saidCaller
		mt.Until(t, func() error {
			answered, err := asker.Ask(key, map[string]any{"caller": "novox.node-tools",
				"_meta": map[string]any{"mesh/caller": "novox.controller"}}, "")
			if err == nil {
				err = json.Unmarshal(answered.Result, &got)
			}
			return err
		})
		if got.Caller != "shanks.node-tools" {
			t.Errorf("%s reached the module with caller %q, want the asker's bus user", key, got.Caller)
		}
		if got.Arguments["caller"] != "novox.node-tools" {
			t.Errorf("%s: the arguments did not reach the module as sent: %v", key, got.Arguments)
		}
	}
}

// The subject that names no caller is still served, for one release (retired by hq issue 464), and says so:
// the module is named no caller, whatever the body claims.
func TestTheSubjectThatNamesNoCallerStillWorksAndNamesNone(t *testing.T) {
	mesh := mt.New(t)
	mesh.Issue(t, mt.MembershipOf("ledger", "anchor", true, map[string][]string{"node-desk": {"who"}}))
	nodeTools := connect(t, "node-tools", "anchor")
	stop, err := Run(nodeTools, []Served{{"ledger", []string{mt.Fixture("caller-echo.py")}}}, nil, func(string, ...any) {})
	if err != nil {
		t.Fatal(err)
	}
	defer stop()
	old, err := nats.Connect(mt.URL(t))
	if err != nil {
		t.Fatal(err)
	}
	defer old.Close()
	body, _ := json.Marshal(map[string]any{"_meta": map[string]any{"mesh/caller": "novox.controller"}})
	for _, subject := range []string{"mesh.mod.ledger.tool.who", "mesh.mod.ledger.tool.who.anchor", "mesh.seat.node-desk.tool.who.anchor"} {
		var reply struct {
			Result saidCaller `json:"result"`
			Error  string     `json:"error"`
		}
		mt.Until(t, func() error {
			msg, err := old.Request(subject, body, 5*time.Second)
			if err == nil {
				err = json.Unmarshal(msg.Data, &reply)
			}
			return err
		})
		if reply.Error != "" || reply.Result.Caller != "" {
			t.Errorf("%s: the module was named caller %q (error %q), want none", subject, reply.Result.Caller, reply.Error)
		}
	}
}