package web

import (
	"io"
	"log"
	"net/http"
	"net/http/httptest"
	"net/url"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"gitea.dooplex.hu/admin/felhom-controller/internal/backup"
	"gitea.dooplex.hu/admin/felhom-controller/internal/config"
	"gitea.dooplex.hu/admin/felhom-controller/internal/settings"
)

// R-103 Group D — the surface: the refusal becomes an action.
//
// Before v0.229.0 an app whose Tier-2 copy held only a recovery unit got a message telling it to
// press a button on a DIFFERENT page. The data it was asking for is in the copy it is looking at, and
// since R-102 it is restorable from there. The action now lives where the refusal was.
//
// Every string assertion here compares against the NAMED CONSTANT rather than a Hungarian literal
// retyped in the test. That is R-364 discipline in its strongest form: a grep for accented text
// returned zero for strings that were present, and a re-typed literal can differ from the shipped one
// by a character nobody sees.

// --- the surface (template) -----------------------------------------------------------------

// r103Row is a Tier-2-configured row with a successful copy — the shape the template needs before it
// will render the actions block at all.
func r103Row(t *testing.T, unitRestorable bool, date string, proven bool) AppBackupRow {
	row := AppBackupRow{
		StackName: "docmost", DisplayName: "Docmost",
		Tier2Configured: true, Tier2Dest: "flash", Tier2Schedule: "Naponta",
		Tier2LastRun: date, Tier2LastStatus: "ok", Tier2StatusBadge: "Sikeres",
		Tier2LastSuccess: date, Tier2SuccessTracked: true,
		Tier2UnitRestorable: unitRestorable,
	}
	if unitRestorable {
		row.Tier2CopyDate, row.Tier2CopyDateProven = date, proven
		row.Tier2UnitConfirm = noteServer(t).tier2UnitConfirmMsg(date, proven)
	}
	return row
}

// D1 — TestR103_UnitActionOfferedWhenTheMirrorExists.
func TestR103_UnitActionOfferedWhenTheMirrorExists(t *testing.T) {
	html := renderBackupPage(t, "backups_apps", baseBackupData([]AppBackupRow{
		r103Row(t, true, "2026-08-25T03:30:00Z", true),
	}))
	if !strings.Contains(html, `action="/backup/tier2/unit-restore"`) {
		t.Error("the unit-restore form is not on the page — the refusal is still a dead end")
	}
	if !strings.Contains(html, noteHU(t, tier2UnitActionLabelKey)) {
		t.Errorf("the action is not labelled %q", noteHU(t, tier2UnitActionLabelKey))
	}
	// The additive action must still be there, separately. Merging them is forbidden: they are
	// different promises (one adds, one overwrites).
	if !strings.Contains(html, `action="/backup/tier2/restore"`) {
		t.Error("the additive file restore disappeared from the row")
	}
	// The destructive one is visually distinct from the additive one beside it.
	if !strings.Contains(html, "btn-danger-outline") {
		t.Error("the destructive action does not carry a danger style")
	}
}

// D2 — TestR103_UnitActionAbsentWhenItDoesNot. Scenario G: no legs and no openable unit → an honest
// refusal, and NO unit action. A button offered over a copy the restore would refuse is worse than no
// button, because it is a promise withdrawn at the moment of use.
func TestR103_UnitActionAbsentWhenItDoesNot(t *testing.T) {
	html := renderBackupPage(t, "backups_apps", baseBackupData([]AppBackupRow{
		r103Row(t, false, "2026-08-25T03:30:00Z", true),
	}))
	if strings.Contains(html, "/backup/tier2/unit-restore") {
		t.Error("the unit action was offered for a copy with no openable unit")
	}
	if strings.Contains(html, noteHU(t, tier2UnitActionLabelKey)) {
		t.Error("the unit action's label leaked onto a row that must not offer it")
	}
	// NEGATIVE CONTROL for D1's assertions: the row itself did render, so D1's positives were not
	// an artefact of the whole block being absent.
	if !strings.Contains(html, `action="/backup/tier2/restore"`) {
		t.Fatal("the row did not render at all — D1's positive assertions prove nothing")
	}
}

// D3 — TestR103_ConfirmStatesTheOverwrite. The confirm must carry the DIFFERENCE the register
// requires: a destructive operation reached from a non-destructive surface says so, and says how it
// differs from the action beside it.
func TestR103_ConfirmStatesTheOverwrite(t *testing.T) {
	confirm := noteServer(t).tier2UnitConfirmMsg("2026-08-25T03:30:00Z", true)

	if !strings.Contains(confirm, noteHU(t, tier2UnitConfirmBaseKey)) {
		t.Error("the confirm does not state that the operation OVERWRITES live data")
	}
	if !strings.Contains(confirm, noteHU(t, tier2UnitConfirmContrastKey)) {
		t.Error("the confirm does not state how it differs from the additive restore beside it")
	}
	// NEGATIVE CONTROL: the additive restore's own confirm must NOT have acquired this language.
	// Without it, a test that passed because both buttons warn about overwriting would look green.
	html := renderBackupPage(t, "backups_apps", baseBackupData([]AppBackupRow{
		r103Row(t, true, "2026-08-25T03:30:00Z", true),
	}))
	fileConfirmStart := strings.Index(html, "Visszaállítja a hiányzó fájlokat")
	if fileConfirmStart < 0 {
		t.Fatal("the additive confirm is gone — the negative control has nothing to check")
	}
	fileConfirm := html[fileConfirmStart:]
	if end := strings.Index(fileConfirm, `">`); end > 0 {
		fileConfirm = fileConfirm[:end]
	}
	if strings.Contains(fileConfirm, "FEL") {
		t.Errorf("the ADDITIVE confirm gained overwrite language: %q", fileConfirm)
	}
	// And the confirm reaches the markup as the rendered attribute, not only as a Go constant.
	if !strings.Contains(html, `data-confirm=`) {
		t.Error("no data-confirm attribute rendered")
	}
	if !strings.Contains(html, "FEL") {
		t.Error("the destructive wording never reached the page")
	}
}

// D4 — TestR103_ConfirmNamesTheCopyDate. Scenario E. The action overwrites live data with a copy of a
// certain age, and „nobody restores last week over today by accident" is only true if the date is on
// the screen. R-101 governs the wording when the date is an ATTEMPT rather than a proven copy.
func TestR103_ConfirmNamesTheCopyDate(t *testing.T) {
	const stamp = "2026-08-25T03:30:00Z"
	rendered := fmtRFC3339Local(stamp)
	if rendered == stamp {
		t.Fatal("the stamp did not render as a local date — the assertion below would be vacuous")
	}

	proven := noteServer(t).tier2UnitConfirmMsg(stamp, true)
	if !strings.Contains(proven, rendered) {
		t.Errorf("the confirm does not name the copy's date: %q", proven)
	}
	unproven := noteServer(t).tier2UnitConfirmMsg(stamp, false)
	if !strings.Contains(unproven, rendered) {
		t.Errorf("the unproven confirm does not name the date: %q", unproven)
	}
	if proven == unproven {
		t.Error("a proven copy and a bare attempt got the SAME sentence — R-101 exactly")
	}
	// A copy with no recorded date still gets the warning; it just cannot name one.
	none := noteServer(t).tier2UnitConfirmMsg("", false)
	if !strings.Contains(none, noteHU(t, tier2UnitConfirmBaseKey)) || !strings.Contains(none, noteHU(t, tier2UnitConfirmContrastKey)) {
		t.Errorf("a dateless copy lost its confirm entirely: %q", none)
	}

	// And it is on the page, not merely constructible.
	html := renderBackupPage(t, "backups_apps", baseBackupData([]AppBackupRow{r103Row(t, true, stamp, true)}))
	if !strings.Contains(html, rendered) {
		t.Errorf("the copy's date %q is not in the rendered row", rendered)
	}
}

// TestR103_AvailableMsgNamesTheButtonByItsLabel — the refusal that now points AT the new action must
// name it by the label the button actually carries, or it points at nothing.
func TestR103_AvailableMsgNamesTheButtonByItsLabel(t *testing.T) {
	if !strings.Contains(noteHU(t, tier2UnitAvailableKey), noteHU(t, tier2UnitActionLabelKey)) {
		t.Errorf("noteHU(t, tier2UnitAvailableKey) does not name %q", noteHU(t, tier2UnitActionLabelKey))
	}
	// It must NOT send anyone to another page any more; that is the R-103 defect it replaces.
	if strings.Contains(noteHU(t, tier2UnitAvailableKey), "oldalon") {
		t.Error("the message still routes the customer to another page for a copy restorable here")
	}
	// The surviving no-coverage message still names the route that works.
	if !strings.Contains(noteHU(t, tier2NoCoverageKey), "oldalon") {
		t.Error("noteHU(t, tier2NoCoverageKey) no longer names any route — Scenario G requires one")
	}
	// C3 — the not-covered sentence is NOT deleted: it is still appended where the FILE restore ran.
	// Since v0.254.0 it is a SAVED note written in the box's language, so the key is what the source
	// names and the bundle is what carries the sentence; both halves are checked.
	if noteHU(t, tier2UnitNotCoveredKey) == "" {
		t.Fatal("the not-covered sentence was deleted from the bundle")
	}
	if !strings.Contains(readSourceFile(t, "handlers.go"), `msg += " " + s.note(tier2UnitNotCoveredKey)`) {
		t.Error("the not-covered sentence is no longer appended by the file-restore handler")
	}
}

func readSourceFile(t *testing.T, name string) string {
	t.Helper()
	b, err := os.ReadFile(name)
	if err != nil {
		t.Fatal(err)
	}
	return string(b)
}

// --- the handler ----------------------------------------------------------------------------

// r103Provider is a StackDataProvider that completes every lifecycle call, so the restore goroutine
// runs to its outcome instead of parking.
type r103Provider struct{ hdd string }

func (p *r103Provider) GetStackComposePath(string) (string, bool) { return "", false }
func (p *r103Provider) ListDeployedStacks() []backup.StackSummary { return nil }
func (p *r103Provider) GetStackHDDMounts(string) []string         { return nil }
func (p *r103Provider) GetStackHDDPath(string) string             { return p.hdd }
func (p *r103Provider) GetImportRoot() string                     { return "" }
func (p *r103Provider) GetDockerVolumes(string) []string          { return nil }
func (p *r103Provider) StopStack(string) error                    { return nil }
func (p *r103Provider) StartStack(string) error                   { return nil }
func (p *r103Provider) RefreshAndIsRunning(string) bool           { return true }
func (p *r103Provider) GetStackRecoveryInfo(string) (backup.RecoveryInfo, bool) {
	return backup.RecoveryInfo{}, false
}
func (p *r103Provider) GetStackClassifiedBinds(string) ([]backup.ClassifiedBind, bool) {
	return nil, false
}
func (p *r103Provider) RecoverStackSecrets(string, []string) map[string]string { return nil }
func (p *r103Provider) RecreateStackDefinitionFromUnit(string, string, map[string]string) error {
	return nil
}
func (p *r103Provider) StartStackServices(string, []string) error { return nil }

const r103CopyStamp = "2026-08-25T03:30:00Z"

// newR103Server wires a Server over a real backup.Manager whose recorded Tier-2 copy for "app" holds
// an OPENABLE recovery unit mirror. Nothing is stubbed between the handler and the manager: the whole
// point of D6 is that the wiring is what is under test.
func newR103Server(t *testing.T, withUnit bool) (*Server, *backup.Manager) {
	t.Helper()
	tmp := t.TempDir()
	live := filepath.Join(tmp, "usb")
	dest := filepath.Join(tmp, "flash")
	lg := log.New(io.Discard, "", 0)
	sett, err := settings.Load(filepath.Join(tmp, "settings.json"), lg)
	if err != nil {
		t.Fatal(err)
	}
	for _, p := range []string{live, dest} {
		if err := sett.AddStoragePath(settings.StoragePath{Path: p, Label: filepath.Base(p)}); err != nil {
			t.Fatal(err)
		}
	}
	if err := sett.SetCrossDriveConfig("app", &settings.CrossDriveBackup{
		Enabled: true, Method: "rsync", DestinationPath: dest,
		LastRun: r103CopyStamp, LastSuccess: r103CopyStamp, SuccessTracked: true, LastStatus: "ok",
	}); err != nil {
		t.Fatal(err)
	}
	destBase := filepath.Join(dest, "backups", "secondary", "app")
	write := func(rel, body string) {
		p := filepath.Join(destBase, rel)
		if err := os.MkdirAll(filepath.Dir(p), 0o755); err != nil {
			t.Fatal(err)
		}
		if err := os.WriteFile(p, []byte(body), 0o644); err != nil {
			t.Fatal(err)
		}
	}
	write(".felhom-tier2-layout", "2")
	if withUnit {
		write("recovery-unit/manifest.json", `{"schema_version":1,"app_name":"app"}`)
		write("recovery-unit/compose/app.yaml", "deployed: true\nenv:\n  SUBDOMAIN: app\n")
		write("recovery-unit/compose/docker-compose.yml", "services:\n  app:\n    image: example/app:1\n")
	} else {
		// A directory that exists and is not a package — the fail-closed case.
		if err := os.MkdirAll(filepath.Join(destBase, "recovery-unit"), 0o755); err != nil {
			t.Fatal(err)
		}
	}
	cfg := &config.Config{}
	cfg.Paths.DataDir = tmp
	m := backup.NewManager(cfg, sett, lg)
	m.SetStackProvider(&r103Provider{hdd: live})
	return &Server{cfg: cfg, backupMgr: m, logger: lg}, m
}

func postTier2UnitRestore(t *testing.T, s *Server, stack string) *httptest.ResponseRecorder {
	t.Helper()
	form := url.Values{"stack_name": {stack}}
	req := httptest.NewRequest(http.MethodPost, "/backup/tier2/unit-restore", strings.NewReader(form.Encode()))
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	rec := httptest.NewRecorder()
	s.backupTier2UnitRestoreHandler(rec, req)
	return rec
}

func waitRestoreDone(t *testing.T, m *backup.Manager) backup.RestoreOpStatus {
	t.Helper()
	deadline := time.Now().Add(30 * time.Second)
	for time.Now().Before(deadline) {
		st := m.RestoreStatus()
		if !st.Running && st.Last != nil {
			return st
		}
		time.Sleep(50 * time.Millisecond)
	}
	t.Fatal("the restore never published a result")
	return backup.RestoreOpStatus{}
}

// D5 — TestR103_SecondPressIsRefused. Scenario H, R-351b. The concurrency flag is only taken inside
// the goroutine, AFTER the handler returns, so a guard reading IsRunning() alone leaves a window in
// which a second press starts a second run and is told „elindult".
func TestR103_SecondPressIsRefused(t *testing.T) {
	s, m := newR103Server(t, true)
	m.BeginRestoreOp("restore", "other-app") // a restore is already in flight, display-flag set

	rec := postTier2UnitRestore(t, s, "app")
	loc := rec.Header().Get("Location")
	if !strings.Contains(loc, "flash_error") {
		t.Fatalf("a second press was accepted: %q", loc)
	}
	// The identity of the FIRST operation survives — the consequence, not which flag was read.
	if st := m.RestoreStatus(); st.Stack != "other-app" {
		t.Errorf("the in-flight op was replaced by the refused one: %+v", st)
	}
}

// D6 — TestR103_HandlerPublishesTheOutcome. THE SEAM TEST.
//
// It reads the outcome off RestoreStatus().Last.Message — the only place a customer sees it — rather
// than calling the manager and inspecting a return value. Three shipped defects in this project came
// from testing a component whose caller never invoked it (R-106's fakeObserver being the clearest),
// and the mechanism here is exactly that shape: a correct RestoreTier2Unit wired to nothing would
// leave the banner silent and every manager-level test green.
//
// Red-proof (recorded in REPORT.md): drop the `s.backupMgr.EndRestoreOp(true, msg)` call at the end
// of the handler's goroutine → this test fails on "the restore never published a result".
func TestR103_HandlerPublishesTheOutcome(t *testing.T) {
	s, m := newR103Server(t, true)

	rec := postTier2UnitRestore(t, s, "app")
	if rec.Code != http.StatusFound {
		t.Fatalf("status = %d, want 302", rec.Code)
	}
	if loc := rec.Header().Get("Location"); strings.Contains(loc, "flash_error") {
		t.Fatalf("the restore was refused: %q", loc)
	}

	st := waitRestoreDone(t, m)
	if !st.Last.OK {
		t.Fatalf("outcome reported failure: %q", st.Last.Message)
	}
	if st.Last.Stack != "app" || st.Last.Op != "tier2-unit-restore" {
		t.Errorf("the published result names the wrong operation: op=%q stack=%q", st.Last.Op, st.Last.Stack)
	}
	// The sentence is yesterday's honest outcome PLUS the clause naming which copy overwrote the live
	// data (Scenario E). Asserted as an exact composition so neither half can silently vanish.
	wantOutcome := noteServer(t).unitRestoreOutcomeMsg("app", backup.UnitRestoreResult{})
	wantSource := noteServer(t).tier2UnitSourceMsg(backup.Tier2Coverage{CopyLastSuccess: r103CopyStamp})
	if wantSource == "" {
		t.Fatal("the fixture recorded no copy date — the assertion below would be vacuous")
	}
	if want := wantOutcome + " " + wantSource; st.Last.Message != want {
		t.Errorf("published message =\n  %q\nwant\n  %q", st.Last.Message, want)
	}
	if !strings.Contains(st.Last.Message, fmtRFC3339Local(r103CopyStamp)) {
		t.Error("the outcome does not name the date of the copy it restored from")
	}
}

// TestR103_UnitRestoreRefusesAnUnopenableMirrorWithoutStopping — the handler's fail-closed pre-flight.
// A directory is not a package, and refusing before BeginRestoreOp means no banner, no outage and no
// rewritten definition.
func TestR103_UnitRestoreRefusesAnUnopenableMirrorWithoutStopping(t *testing.T) {
	s, m := newR103Server(t, false)

	rec := postTier2UnitRestore(t, s, "app")
	loc := rec.Header().Get("Location")
	if !strings.Contains(loc, "flash_error") {
		t.Fatalf("the restore was accepted over an unopenable mirror: %q", loc)
	}
	// The flash carries a KEY since v0.252.0; the sentence is what this test is about, so it is
	// resolved the way the page resolves it.
	if got := flashSentence(t, loc); got != noteHU(t, tier2NoCoverageKey) {
		t.Errorf("refusal flash = %q, want the no-coverage sentence", got)
	}
	if st := m.RestoreStatus(); st.Running || st.Last != nil {
		t.Errorf("an operation was begun despite the refusal: %+v", st)
	}
}

// TestR103_UnitRestoreHandlerGuards — the same three guards the two restores beside it carry, proven
// to run BEFORE any work (backupMgr is nil, so reaching it would panic).
func TestR103_UnitRestoreHandlerGuards(t *testing.T) {
	s := &Server{logger: log.New(io.Discard, "", 0)} // backupMgr nil on purpose
	for name, want := range map[string]string{
		"../../etc": "%C3%89rv%C3%A9nytelen+alkalmaz%C3%A1sn%C3%A9v",
		"a/b":       "%C3%89rv%C3%A9nytelen+alkalmaz%C3%A1sn%C3%A9v",
		"":          "Hi%C3%A1nyz%C3%B3+param%C3%A9terek",
	} {
		rec := postTier2UnitRestore(t, s, name)
		if loc := rec.Header().Get("Location"); !strings.Contains(loc, want) {
			t.Errorf("%q: redirect = %q, want flash %q", name, loc, want)
		}
	}
	rec := postTier2UnitRestore(t, s, "docmost")
	if loc := rec.Header().Get("Location"); !strings.Contains(flashSentence(t, loc), "Mentés nincs beállítva") {
		t.Errorf("nil backupMgr: redirect = %q", loc)
	}
}

// TestR103_FileRestoreRefusalPointsAtTheActionThatWorks — the R-103 split. An app with no file legs
// but a restorable unit gets the message that names the button beside it, NOT the one that sends it
// to another page.
func TestR103_FileRestoreRefusalPointsAtTheActionThatWorks(t *testing.T) {
	s, _ := newR103Server(t, true)
	rec := postTier2Restore(t, s, "app")
	loc := rec.Header().Get("Location")
	if !strings.Contains(loc, url.QueryEscape(noteHU(t, tier2UnitAvailableKey))) {
		t.Errorf("refusal flash = %q, want noteHU(t, tier2UnitAvailableKey)", loc)
	}
	if strings.Contains(loc, url.QueryEscape(noteHU(t, tier2NoCoverageKey))) {
		t.Error("the old dead-end message is still shown for a copy restorable here")
	}
}