package release

import (
	"crypto/ed25519"
	"encoding/json"
	"os"
	"strings"
	"testing"
	"time"

	"github.com/carlosframework/platform/internal/rootstate"
)

func retirementFixture(t *testing.T) (*RootHistory, *healthyRetryStore, HistoryRecovery, HistoryRecovery, HistoryRecoveryRetirement, ed25519.PublicKey, ed25519.PrivateKey) {
	t.Helper()
	h, s, b := rootHistoryFixture(t)
	now := time.Date(2026, 10, 13, 0, 0, 0, 0, time.UTC)
	old := HistoryRecovery{Binding: b, Attempt: HistoryAttempt{ID: "failed", Source: "canonical", Version: "v2", SHA256: "failed-digest", Platform: AdoptPlatform(), Started: now.Add(-time.Hour), PromotedAt: now.Add(-2 * time.Hour)}, Settled: true, Failed: true}
	good := old
	good.Attempt.ID, good.Attempt.Version, good.Attempt.SHA256 = "verified", "v3", "good-digest"
	good.Attempt.Started, good.Attempt.PromotedAt = now, now
	good.Failed, good.Verified = false, true
	for _, r := range []HistoryRecovery{old, good} {
		if err := h.RetainRecovery(r); err != nil {
			t.Fatal(err)
		}
	}
	status, err := h.ReconstructionStatus()
	if err != nil {
		t.Fatal(err)
	}
	g := HistoryRecoveryRetirement{Schema: 1, Kind: "carlos-release-recovery-retirement", Identity: status.Identity, Operation: "retire-failed", IssuedAt: now, Binding: b, Source: "canonical", AttemptID: old.Attempt.ID, OutcomeDigest: historyRecoveryDigest(old), VerifiedID: good.Attempt.ID, VerifiedDigest: historyRecoveryDigest(good)}
	pub, key, err := ed25519.GenerateKey(nil)
	if err != nil {
		t.Fatal(err)
	}
	return h, s, old, good, g, pub, key
}

func retireForTest(h *RootHistory, g HistoryRecoveryRetirement, pub ed25519.PublicKey, key ed25519.PrivateKey) error {
	wire, err := SignRootEnvelope(RootSigner(key), g)
	if err != nil {
		return err
	}
	return h.RetireRecovery(pub, wire, g.Binding, g.IssuedAt, func(HistoryBinding) (string, error) { return "canonical", nil })
}

func TestPlan14HistoryExactRecoveryRetirement(t *testing.T) {
	for _, ambiguous := range []bool{false, true} {
		t.Run(map[bool]string{false: "failed", true: "ambiguous"}[ambiguous], func(t *testing.T) {
			h, s, old, _, g, pub, key := retirementFixture(t)
			if ambiguous {
				old.Failed = false
				raw, _ := json.Marshal(historyRecoveryRecord{Schema: 1, HistoryRecovery: old})
				if err := s.Write(historyRecoveryKey(old), raw); err != nil {
					t.Fatal(err)
				}
				g.OutcomeDigest = historyRecoveryDigest(old)
			}
			other := old
			other.Attempt.ID = "unrelated"
			other.Attempt.SHA256 = "unrelated-digest"
			other.Failed = true
			if err := h.RetainRecovery(other); err != nil {
				t.Fatal(err)
			}
			if err := retireForTest(h, g, pub, key); err != nil {
				t.Fatal(err)
			}
			h = &RootHistory{Store: s}
			refs, err := h.Refusals(old.Binding)
			if err != nil || len(refs) != 1 || refs[0].SHA256 != "unrelated-digest" {
				t.Fatalf("retirement not exact: %+v %v", refs, err)
			}
			if err := h.RetainRecovery(old); err != nil {
				t.Fatal(err)
			}
			refs, err = h.Refusals(old.Binding)
			if err != nil || len(refs) != 1 {
				t.Fatalf("source replay erased retirement: %+v %v", refs, err)
			}
			if _, err := s.Read(historyRecoveryKey(old)); err != nil {
				t.Fatal("retirement deleted evidence", err)
			}
			if err := h.AddRefusal(old.Binding, Refusal{Host: old.Binding.Host, App: old.Binding.App, Version: old.Attempt.Version, SHA256: old.Attempt.SHA256, Kind: RefusalWrongProgram, RefusedAt: g.IssuedAt, PointerPromotedAt: old.Attempt.PromotedAt}); err != nil {
				t.Fatal(err)
			}
			refs, err = h.Refusals(old.Binding)
			if err != nil || len(refs) != 2 {
				t.Fatalf("retirement cleared another category: %+v %v", refs, err)
			}
		})
	}
}

func TestPlan14HistoryRecoveryRetirementAuthority(t *testing.T) {
	for _, attack := range []string{"signature", "identity", "binding", "source", "outcome", "witness", "pending", "unverified", "failed-witness", "older-witness", "canonical-change", "expired", "reconstruction-pending"} {
		t.Run(attack, func(t *testing.T) {
			h, s, old, good, g, pub, key := retirementFixture(t)
			resolve := func(HistoryBinding) (string, error) { return "canonical", nil }
			now := g.IssuedAt
			switch attack {
			case "signature":
				_, key, _ = ed25519.GenerateKey(nil)
			case "identity":
				g.Identity = strings.Repeat("0", 64)
			case "binding":
				g.Binding.Host = "other.example.com"
			case "source":
				g.Source = "forged"
			case "outcome":
				g.OutcomeDigest = strings.Repeat("0", 64)
			case "witness":
				g.VerifiedDigest = strings.Repeat("0", 64)
			case "pending":
				old.Settled = false
			case "unverified":
				good.Verified = false
			case "failed-witness":
				good.Failed = true
			case "older-witness":
				good.Attempt.Started = old.Attempt.Started
			case "canonical-change":
				calls := 0
				resolve = func(HistoryBinding) (string, error) {
					calls++
					if calls > 1 {
						return "changed", nil
					}
					return "canonical", nil
				}
			case "expired":
				now = now.Add(HostRetryGrantTTL + time.Second)
			case "reconstruction-pending":
				state, err := h.reconstructionState()
				if err != nil {
					t.Fatal(err)
				}
				state.Pending = &reconstructionIntent{}
				if err := h.writeReconstruction(state); err != nil {
					t.Fatal(err)
				}
			}
			if attack == "pending" || attack == "unverified" || attack == "failed-witness" || attack == "older-witness" {
				for _, r := range []HistoryRecovery{old, good} {
					raw, _ := json.Marshal(historyRecoveryRecord{Schema: 1, HistoryRecovery: r})
					if err := s.Write(historyRecoveryKey(r), raw); err != nil {
						t.Fatal(err)
					}
				}
				g.OutcomeDigest, g.VerifiedDigest = historyRecoveryDigest(old), historyRecoveryDigest(good)
			}
			wire, err := SignRootEnvelope(RootSigner(key), g)
			if err != nil {
				t.Fatal(err)
			}
			if err := h.RetireRecovery(pub, wire, old.Binding, now, resolve); err == nil {
				t.Fatal("unauthorized retirement accepted")
			}
			refs, err := h.Refusals(old.Binding)
			if err == nil && len(refs) == 0 {
				t.Fatal("refusal disappeared")
			}
		})
	}
}

type retirementSyncStore struct {
	rootstate.Store
	fail bool
}

func (s *retirementSyncStore) Write(name string, raw []byte) error {
	if err := s.Store.Write(name, raw); err != nil {
		return err
	}
	if s.fail && strings.HasSuffix(name, ".retired") {
		return os.ErrPermission
	}
	return nil
}
func TestPlan14HistoryRetirementVisibleSync(t *testing.T) {
	h, s, old, good, g, pub, key := retirementFixture(t)
	fault := &retirementSyncStore{Store: s, fail: true}
	h.Store = fault
	if err := retireForTest(h, g, pub, key); err == nil {
		t.Fatal("unsynced retirement reported success")
	}
	if refs, err := h.Refusals(old.Binding); err == nil && len(refs) == 0 {
		t.Fatal("unsynced retirement granted permission")
	}
	fault.fail = false
	if refs, err := h.Refusals(old.Binding); err != nil || len(refs) != 0 {
		t.Fatalf("durable retry: %+v %v", refs, err)
	}
	good.Failed = true
	if err := h.RetainRecovery(good); err != nil {
		t.Fatal(err)
	}
	if refs, err := h.Refusals(old.Binding); err == nil && len(refs) < 2 {
		t.Fatalf("changed witness kept retirement: %+v", refs)
	}
	if err := retireForTest(h, g, pub, key); err == nil {
		t.Fatal("old signature retired changed evidence")
	}
}

func TestPlan14HistoryRetirementDelivery(t *testing.T) {
	h, _, old, _, g, pub, key := retirementFixture(t)
	store := NewDirStore(t.TempDir())
	if err := PublishHistoryRecoveryRetirement(t.Context(), store, RootSigner(key), g); err != nil {
		t.Fatal(err)
	}
	resolve := func(HistoryBinding) (string, error) { return "canonical", nil }
	if err := h.ReceiveRecoveryRetirements(t.Context(), store, pub, old.Binding, g.IssuedAt, resolve); err != nil {
		t.Fatal(err)
	}
	view, err := h.MigrationStatus(old.Binding, resolve)
	if err != nil || len(view.Hosts) != 1 || len(view.Hosts[0].RetiredRecoveries) != 1 || view.Hosts[0].RecoveryDigests[old.Attempt.ID] != g.OutcomeDigest {
		t.Fatalf("retirement status: %+v %v", view, err)
	}
	if err := h.ReceiveRecoveryRetirements(t.Context(), store, pub, old.Binding, g.IssuedAt.Add(2*HostRetryGrantTTL), resolve); err != nil {
		t.Fatal("committed retirement expired", err)
	}
}