package nodeengineclient

import (
	"errors"
	"strings"
	"testing"
	"time"

	seat "git.novox.be/novox/mesh-contracts/go/seats/nodeengine"
	"git.novox.be/novox/mesh-sdk/go/keys"
)

const digestA = "sha256:0000000000000000000000000000000000000000000000000000000000000001"

func TestHaveCodec(t *testing.T) {
	good := seat.HaveByNodeModuleValue{Phase: PhaseRunning, Health: HealthOK, Composed: digestA, Fp: "src2:x"}
	waiting := seat.HaveByNodeModuleValue{Phase: PhaseWaitingYes, Health: HealthOK, Judgement: JudgedRecreates, Waits: digestA}
	pull := &seat.PullWait{Image: "i", Holder: "h"}
	tests := map[string]struct {
		have seat.HaveByNodeModuleValue
		bad  string
	}{
		"running":                  {good, ""},
		"waiting for a yes":        {waiting, ""},
		"unknown phase":            {seat.HaveByNodeModuleValue{Phase: "gone", Health: HealthOK}, "phase"},
		"unknown health":           {seat.HaveByNodeModuleValue{Phase: PhaseRunning, Health: "fine"}, "health"},
		"judgement outside a yes":  {seat.HaveByNodeModuleValue{Phase: PhaseRunning, Health: HealthOK, Judgement: JudgedCannot}, "judgement"},
		"a yes without a digest":   {seat.HaveByNodeModuleValue{Phase: PhaseWaitingYes, Health: HealthOK, Judgement: JudgedCannot, Waits: "x"}, "sha256"},
		"pull wait on a running":   {seat.HaveByNodeModuleValue{Phase: PhaseRunning, Health: HealthOK, PullWait: pull}, "pull"},
		"pull wait without holder": {seat.HaveByNodeModuleValue{Phase: PhaseFailed, Health: HealthFailed, PullWait: &seat.PullWait{Image: "i"}}, "holder"},
		"bad composed digest":      {seat.HaveByNodeModuleValue{Phase: PhaseRunning, Health: HealthOK, Composed: "abc"}, "sha256"},
	}
	for name, tc := range tests {
		t.Run(name, func(t *testing.T) {
			raw, err := EncodeHave(tc.have)
			if tc.bad != "" {
				if err == nil || !strings.Contains(err.Error(), tc.bad) {
					t.Fatalf("encode: %v, want it to name %q", err, tc.bad)
				}
				return
			}
			if err != nil {
				t.Fatal(err)
			}
			back, err := DecodeHave(raw)
			if err != nil {
				t.Fatal(err)
			}
			tc.have.V = keys.Version
			if !SameHave(back, tc.have) {
				t.Fatalf("round trip differs: %+v", back)
			}
		})
	}
	if _, err := DecodeHave([]byte(`{"v":2,"phase":"running","health":"ok"}`)); !errors.Is(err, keys.ErrUnknownVersion) {
		t.Fatalf("version 2: %v", err)
	}
	if _, err := DecodeHave([]byte(`{"v":1,"phase":"running","health":"ok","extra":1}`)); err == nil {
		t.Fatal("an unknown field is read")
	}
}

func TestSameHaveComparesTimesAsInstants(t *testing.T) {
	at := time.Date(2026, 11, 5, 12, 0, 0, 0, time.UTC)
	zone := time.FixedZone("x", 3600)
	mk := func(tm time.Time) seat.HaveByNodeModuleValue {
		return seat.HaveByNodeModuleValue{Phase: PhaseFailed, Health: HealthFailed,
			PullWait: &seat.PullWait{Image: "i", Holder: "h", Began: tm},
			UserList: &seat.UserListWritten{Source: "s", At: tm}}
	}
	if !SameHave(mk(at), mk(at.In(zone))) {
		t.Fatal("the same instant in another zone differs")
	}
	if SameHave(mk(at), mk(at.Add(time.Second))) {
		t.Fatal("another instant is the same")
	}
}

func TestHaveNodeCodec(t *testing.T) {
	n := seat.HaveByNodeNodeValue{Composed: digestA, Composes: ComposesOwn,
		Candidates: map[string]seat.CandidateAnswer{"g": {Proposal: "p", Verdict: seat.CandidateAnswerVerdictSame}}}
	raw, err := EncodeHaveNode(n)
	if err != nil {
		t.Fatal(err)
	}
	back, err := DecodeHaveNode(raw)
	if err != nil {
		t.Fatal(err)
	}
	n.V = keys.Version
	if !SameHaveNode(back, n) {
		t.Fatalf("round trip differs: %+v", back)
	}
	for name, bad := range map[string]seat.HaveByNodeNodeValue{
		"composes":  {Composes: "other"},
		"no group":  {Candidates: map[string]seat.CandidateAnswer{"": {Verdict: "same"}}},
		"a verdict": {Candidates: map[string]seat.CandidateAnswer{"g": {Verdict: "maybe"}}},
	} {
		if _, err := EncodeHaveNode(bad); err == nil {
			t.Errorf("%s: encoded", name)
		}
	}
	a, b := seat.NodeRecord{Node: "n", V: 1}, seat.NodeRecord{Node: "n", V: 2}
	if !SameNodeRecord(a, b) {
		t.Error("a record differs by its version")
	}
}

func TestHealthAndDataCodecs(t *testing.T) {
	at := time.Date(2026, 11, 5, 12, 0, 0, 0, time.UTC)
	h := seat.HealthByNodeValue{Node: "n", At: at, Fallback: &seat.LoginFallback{Node: "n", From: "old", Why: "w", At: at}}
	raw, err := EncodeHealth(h)
	if err != nil {
		t.Fatal(err)
	}
	back, err := DecodeHealth(raw)
	h.V = keys.Version
	if err != nil || !SameHealth(back, h) {
		t.Fatalf("round trip: %v %+v", err, back)
	}
	later := h
	later.At = at.Add(time.Hour)
	if !SameHealth(h, later) {
		t.Error("a report differs by its time of writing")
	}
	for name, bad := range map[string]seat.HealthByNodeValue{
		"no node":       {},
		"another node":  {Node: "n", Fallback: &seat.LoginFallback{Node: "m", From: "o", Why: "w", At: at}},
		"no time":       {Node: "n", Fallback: &seat.LoginFallback{Node: "n", From: "o", Why: "w"}},
		"no login from": {Node: "n", Fallback: &seat.LoginFallback{Node: "n", Why: "w", At: at}},
	} {
		if _, err := EncodeHealth(bad); err == nil {
			t.Errorf("%s: encoded", name)
		}
	}
	if _, err := DecodeHealth([]byte(`{"v":2,"node":"n"}`)); !errors.Is(err, keys.ErrUnknownVersion) {
		t.Errorf("version 2: %v", err)
	}
	d := seat.DataByNodeModuleValue{Node: "n", Module: "m", Digest: digestA}
	raw, err = EncodeData(d)
	if err != nil || !strings.Contains(string(raw), `"items":[]`) {
		t.Fatalf("data: %v %s", err, raw)
	}
	if _, err := EncodeData(seat.DataByNodeModuleValue{Node: "n", Module: "node"}); err == nil {
		t.Error("the module name node keys")
	}
	if k, err := HaveNodeKey("n"); err != nil || k != "n.node" {
		t.Errorf("node key %q %v", k, err)
	}
}

// The lists a node's facts carry (windows, busy, strays, filters) are arrays on the bus, as the engine has always written
// them; the contract once said objects and refused every real value.
func TestHaveNodeReadsTheListsTheEngineWrites(t *testing.T) {
	raw := []byte(`{"v":1,"windows":[{"step":"backup"}],"busy":[{"id":"x"}],"strays":[{"kind":"container"}],"filters":[{"name":"f"}]}`)
	n, err := DecodeHaveNode(raw)
	if err != nil {
		t.Fatal(err)
	}
	if len(n.Windows) != 1 || len(n.Busy) != 1 || len(n.Strays) != 1 || len(n.Filters) != 1 {
		t.Fatalf("lists lost: %+v", n)
	}
}