package web

import (
	"io"
	"log"
	"net/http"
	"net/http/httptest"
	"os"
	"path/filepath"
	"strings"
	"sync/atomic"
	"testing"

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

// C9-F1 at the customer surface. Two messages had to change, and they fail differently:
//
//   - the LOUD lie: for the 43 apps whose data the restore cannot read, the customer got an outage
//     and „Nincs hiányzó fájl — minden fájl megvan a helyén." — pressed precisely BECAUSE files were
//     missing;
//   - the QUIET one: for the 9 apps it does cover, it covers only the file legs, never the database
//     or named volumes, so the same blanket sentence was a clean bill of health over data the
//     operation never opened (immich's 1.3 GB Postgres unit is the dangerous case).

// honestProvider is a minimal provider: the restore must never reach StopStack in the no-coverage
// test, and `stops` is the assertion that proves it.
type honestProvider struct {
	hdd   string
	stops int32
}

func (p *honestProvider) GetStackComposePath(string) (string, bool) { return "", false }
func (p *honestProvider) ListDeployedStacks() []backup.StackSummary { return nil }
func (p *honestProvider) GetStackHDDMounts(string) []string         { return nil }
func (p *honestProvider) GetStackHDDPath(string) string             { return p.hdd }
func (p *honestProvider) GetImportRoot() string                     { return "" }
func (p *honestProvider) GetDockerVolumes(string) []string          { return nil }
func (p *honestProvider) StopStack(string) error                    { atomic.AddInt32(&p.stops, 1); return nil }
func (p *honestProvider) StartStack(string) error                   { return nil }
func (p *honestProvider) RefreshAndIsRunning(string) bool           { return true }
func (p *honestProvider) GetStackRecoveryInfo(string) (backup.RecoveryInfo, bool) {
	return backup.RecoveryInfo{}, false
}
func (p *honestProvider) GetStackClassifiedBinds(string) ([]backup.ClassifiedBind, bool) {
	return nil, false
}
func (p *honestProvider) RecoverStackSecrets(string, []string) map[string]string { return nil }
func (p *honestProvider) RecreateStackDefinitionFromUnit(string, string, map[string]string) error {
	return nil
}
func (p *honestProvider) StartStackServices(string, []string) error { return nil }

// newHonestServer builds a server whose recorded Tier-2 copy has `legs` (each created as a dir) and,
// optionally, a recovery unit — so one harness expresses both the class-A and class-B shapes.
func newHonestServer(t *testing.T, legs []string, withUnit bool) (*Server, *honestProvider) {
	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: "2026-07-28T03:30:00Z", LastStatus: "ok",
	}); err != nil {
		t.Fatal(err)
	}
	destBase := filepath.Join(dest, "backups", "secondary", "app")
	for _, leg := range legs {
		if err := os.MkdirAll(filepath.Join(destBase, leg, "appdata"), 0o755); err != nil {
			t.Fatal(err)
		}
	}
	if withUnit {
		if err := os.MkdirAll(filepath.Join(destBase, "recovery-unit", "volume-dumps"), 0o755); err != nil {
			t.Fatal(err)
		}
	}
	if err := os.WriteFile(filepath.Join(destBase, ".felhom-tier2-layout"), []byte("2"), 0o644); err != nil {
		t.Fatal(err)
	}
	cfg := &config.Config{}
	cfg.Paths.DataDir = tmp
	m := backup.NewManager(cfg, sett, lg)
	prov := &honestProvider{hdd: live}
	m.SetStackProvider(prov)
	return &Server{cfg: cfg, backupMgr: m, logger: lg}, prov
}

// SCENARIO D at the surface — the customer is told plainly, up front, and the app is NOT stopped.
// The message must NAME the action that works; a dead end for 81% of the catalog is not honesty.
//
// RED-PROOF (observed): remove the pre-flight `!cov.CanRestore()` block from the handler →
//
//	tier2_honest_message_test.go:118: no flash_error — the customer was told the restore STARTED
//	tier2_honest_message_test.go:129: THE APP WAS STOPPED (stops=1) for a restore that can never restore anything
func TestTier2RestoreHandler_NoCoverage_RefusesUpFrontAndNamesTheAction(t *testing.T) {
	s, prov := newHonestServer(t, nil, true) // bookstack shape: unit only, no legs

	req := httptest.NewRequest(http.MethodPost, "/backup/tier2/restore", strings.NewReader("stack_name=app"))
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	w := httptest.NewRecorder()
	s.backupTier2RestoreHandler(w, req)

	loc := w.Header().Get("Location")
	if !strings.Contains(loc, "flash_error=") {
		t.Fatalf("no flash_error — the customer was told the restore STARTED: %s", loc)
	}
	// The refusal must not have started an operation at all.
	if st := s.backupMgr.RestoreStatus(); st.Running {
		t.Error("an async op was begun for a restore that cannot do anything")
	}
	if got := atomic.LoadInt32(&prov.stops); got != 0 {
		t.Errorf("THE APP WAS STOPPED (stops=%d) for a restore that can never restore anything", got)
	}
	// The message names the working action rather than dead-ending.
	for _, want := range []string{"nem ebből a másolatból", "nem állt le", "Visszaállítás indítása"} {
		if !strings.Contains(tier2NoCoverageMsg, want) {
			t.Errorf("the refusal message is missing %q:\n%s", want, tier2NoCoverageMsg)
		}
	}
}

// SCENARIO F — „nothing missing" must claim only what was EXAMINED, and must disclose what this
// restore does not cover at all.
//
// RED-PROOF (observed): restore the old blanket string
// (`msg := "Nincs hiányzó fájl — minden fájl megvan a helyén."` with no disclosure) →
//
//	tier2_honest_message_test.go:154: the success message still claims ALL files: "Nincs hiányzó fájl — minden fájl megvan a helyén."
//	tier2_honest_message_test.go:161: the message does not disclose that the database and volumes were not covered
func TestTier2RestoreHandler_CoveredApp_ClaimsOnlyWhatWasExamined(t *testing.T) {
	s, _ := newHonestServer(t, []string{"hdd"}, true) // paperless shape: a leg AND a unit

	req := httptest.NewRequest(http.MethodPost, "/backup/tier2/restore", strings.NewReader("stack_name=app"))
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	w := httptest.NewRecorder()
	s.backupTier2RestoreHandler(w, req)

	if !strings.Contains(w.Header().Get("Location"), "flash=") {
		t.Fatalf("a COVERED app was refused — this is the regression guard on Campaign 9's A1 result: %s", w.Header().Get("Location"))
	}

	var last backup.RestoreOpResult
	waitFor(t, func() bool {
		st := s.backupMgr.RestoreStatus()
		if st.Running || st.Last == nil {
			return false
		}
		last = *st.Last
		return true
	}, "the restore to finish")

	if !last.OK {
		t.Fatalf("a covered app's restore failed: %s", last.Message)
	}
	if strings.Contains(last.Message, "minden fájl megvan a helyén") {
		t.Errorf("the success message still claims ALL files: %q", last.Message)
	}
	if !strings.Contains(last.Message, "vizsgált") {
		t.Errorf("the message does not limit its claim to what was EXAMINED: %q", last.Message)
	}
	if !strings.Contains(last.Message, tier2UnitNotCoveredMsg) {
		t.Errorf("the message does not disclose that the database and volumes were not covered: %q", last.Message)
	}
}