package test

import (
	"RenewCMS/api"
	"RenewCMS/api/pkg/apperr"
	validator "RenewCMS/api/pkg/validator"
	"RenewCMS/internal/domain/update"
	"RenewCMS/internal/infrastructure/config"
	"RenewCMS/internal/infrastructure/storage"
	infraUpdate "RenewCMS/internal/infrastructure/update"
	"RenewCMS/internal/infrastructure/useCases"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"os"
	"path/filepath"
	"runtime"
	"strings"
	"sync"
	"testing"
	"time"

	"github.com/go-chi/jwtauth/v5"
)

const restartPath = "/update/restart"

type restartHTTP struct {
	router      http.Handler
	token       *jwtauth.JWTAuth
	dataDir     string
	markerPath  string
	resultPath  string
	store       *fakeUpdateStore
	jobs        *fakeJobStore
	helper      *fakeHelperDetector
	clock       *fakeClock
	markers     update.RestartRequestStore
	resultFiles update.ResultStore
}

func newRestartHTTP(t *testing.T) *restartHTTP {
	t.Helper()
	validator.InitValidator()
	dataDir := t.TempDir()
	h := &restartHTTP{
		token:      jwtauth.New("HS256", []byte("test-secret"), nil),
		dataDir:    dataDir,
		markerPath: filepath.Join(dataDir, update.RestartRequestFileName),
		resultPath: filepath.Join(dataDir, update.ResultFileName),
		store:      &fakeUpdateStore{result: newStoredUpdateResult(), found: true},
		jobs:       &fakeJobStore{},
		helper:     &fakeHelperDetector{installed: true},
		clock:      &fakeClock{now: restartBaseTime},
	}
	h.markers = infraUpdate.NewJSONRestartRequestStore(h.markerPath)
	h.resultFiles = infraUpdate.NewJSONResultStore(h.resultPath)
	container := &api.UseCases{
		Token:              h.token,
		GetUserUseCase:     useCases.NewGetUserUseCase(newUpdateUserRepo()),
		GetMyAuthorUseCase: useCases.NewGetMyAuthorUseCase(plainAuthors()),
		GetUpdateStatusUseCase: useCases.NewGetUpdateStatusUseCase(
			h.store, h.jobs, h.helper, h.resultFiles, h.markers, updateRunning, false, h.clock.Now),
		RequestRestartUseCase: useCases.NewRequestRestartUseCase(
			h.store, h.jobs, h.helper, h.resultFiles, h.markers, updateRunning, h.clock.Now, discardRecorder),
	}
	h.router = api.NewSystemRouter(container, nil)
	return h
}

func (h *restartHTTP) readyJob() {
	h.jobs.put(update.Job{Tag: downloadTag, State: update.StateReady, StartedAt: restartBaseTime.Add(-time.Hour)})
}

func (h *restartHTTP) post(t *testing.T, userId uint32, tokenVersion uint32, body string) *httptest.ResponseRecorder {
	t.Helper()
	return h.request(t, http.MethodPost, restartPath, userId, tokenVersion, body)
}

func (h *restartHTTP) postAsOwner(t *testing.T, body string) *httptest.ResponseRecorder {
	t.Helper()
	return h.post(t, updateOwnerId, 2, body)
}

func (h *restartHTTP) request(t *testing.T, method string, target string, userId uint32, tokenVersion uint32, body string) *httptest.ResponseRecorder {
	t.Helper()
	req := httptest.NewRequest(method, target, strings.NewReader(body))
	if userId != 0 {
		_, tokenString, err := h.token.Encode(map[string]any{"user_id": userId, "token_version": tokenVersion})
		if err != nil {
			t.Fatal(err)
		}
		req.AddCookie(&http.Cookie{Name: "jwt", Value: tokenString})
	}
	rec := httptest.NewRecorder()
	h.router.ServeHTTP(rec, req)
	return rec
}

func (h *restartHTTP) getAs(t *testing.T, userId uint32) *httptest.ResponseRecorder {
	t.Helper()
	tokenVersion := uint32(0)
	if userId == updateOwnerId {
		tokenVersion = 2
	}
	return h.request(t, http.MethodGet, "/update", userId, tokenVersion, "")
}

func (h *restartHTTP) markerBytes() ([]byte, bool) {
	content, err := os.ReadFile(h.markerPath)
	return content, err == nil
}

func (h *restartHTTP) seedResult(t *testing.T, result update.Result) {
	t.Helper()
	if err := h.resultFiles.Write(result); err != nil {
		t.Fatal(err)
	}
}

func (h *restartHTTP) assertNoMarkerAndResultKept(t *testing.T, resultKept bool) {
	t.Helper()
	if _, found := h.markerBytes(); found {
		t.Error("no marker may be written")
	}
	if _, found := h.resultFiles.Read(); found != resultKept {
		t.Errorf("result present = %v, want %v", found, resultKept)
	}
}

func TestRestartHTTP(t *testing.T) {
	t.Run("Request an update restart, happy path", func(t *testing.T) {
		for name, body := range map[string]string{"no body": "", "kind update": `{"kind":"update"}`} {
			t.Run(name, func(t *testing.T) {
				h := newRestartHTTP(t)
				h.readyJob()
				h.seedResult(t, update.Result{Outcome: update.OutcomeRolledBack, Kind: update.RestartKindUpdate, Tag: downloadTag, StartedAt: restartBaseTime.Add(-time.Hour), FinishedAt: finishedAt(restartBaseTime.Add(-time.Hour))})

				rec := h.postAsOwner(t, body)

				if rec.Code != http.StatusAccepted {
					t.Fatalf("status = %d: %s", rec.Code, rec.Body.String())
				}
				status := decodeUpdateBody(t, rec)
				assertUpdateKeys(t, status)
				if status["state"] != "restarting" || status["started_at"] != "2026-09-30T09:50:00Z" || status["error"] != nil || status["finished_at"] != nil {
					t.Errorf("status = %v", status)
				}
				marker, err := h.markers.Read()
				if err != nil || marker.Kind != "update" || marker.Tag != downloadTag || marker.RequestedBy != updateOwnerId || !marker.RequestedAt.Equal(restartBaseTime) {
					t.Errorf("marker = %+v, err = %v", marker, err)
				}
				if _, found := h.resultFiles.Read(); found {
					t.Error("update-result.json must be deleted first")
				}
				entries, _ := os.ReadDir(h.dataDir)
				if len(entries) != 1 {
					t.Errorf("only the marker may exist in the data directory, got %d entries", len(entries))
				}
				asAdmin := decodeUpdateBody(t, h.getAs(t, updateAdminId))
				if asAdmin["state"] != "restarting" || asAdmin["can_apply"] != false {
					t.Errorf("admin view = %v", asAdmin)
				}
			})
		}
	})

	t.Run("Request a plain restart", func(t *testing.T) {
		for name, body := range map[string]string{"no body": "", "kind restart": `{"kind":"restart"}`, "empty object": `{}`} {
			t.Run(name, func(t *testing.T) {
				h := newRestartHTTP(t)

				rec := h.postAsOwner(t, body)

				marker, err := h.markers.Read()
				if rec.Code != http.StatusAccepted || err != nil || marker.Kind != "restart" || marker.Tag != "" {
					t.Fatalf("status = %d, marker = %+v, err = %v", rec.Code, marker, err)
				}
				if decodeUpdateBody(t, h.getAs(t, updateOwnerId))["state"] != "restarting" {
					t.Error("GET must report restarting")
				}
			})
		}
	})

	t.Run("The kind must match the state", func(t *testing.T) {
		cases := []struct {
			name    string
			prepare func(*restartHTTP)
			kind    string
		}{
			{"no job ready (idle) with update", func(*restartHTTP) {}, "update"},
			{"a job failed with update", func(h *restartHTTP) {
				h.jobs.put(update.Job{Tag: downloadTag, State: update.StateFailed, Error: "download"})
			}, "update"},
			{"a job ready with restart", func(h *restartHTTP) { h.readyJob() }, "restart"},
		}
		for _, tc := range cases {
			t.Run(tc.name, func(t *testing.T) {
				h := newRestartHTTP(t)
				h.seedResult(t, update.Result{Outcome: update.OutcomeFailed, StartedAt: restartBaseTime, FinishedAt: finishedAt(restartBaseTime)})
				tc.prepare(h)
				jobBefore, _ := h.jobs.Load()

				rec := h.postAsOwner(t, `{"kind":"`+tc.kind+`"}`)

				jobAfter, _ := h.jobs.Load()
				if rec.Code != http.StatusConflict || jobAfter != jobBefore {
					t.Errorf("status = %d", rec.Code)
				}
				h.assertNoMarkerAndResultKept(t, true)
			})
		}
	})

	t.Run("Restart site never installs an update another owner just made ready", func(t *testing.T) {
		h := newRestartHTTP(t)
		h.readyJob()

		rec := h.postAsOwner(t, `{"kind":"restart"}`)

		if rec.Code != http.StatusConflict {
			t.Fatalf("status = %d", rec.Code)
		}
		h.assertNoMarkerAndResultKept(t, false)
		if job, found := h.jobs.Load(); !found || job.State != update.StateReady {
			t.Error("the ready job must stay ready")
		}
		if decodeUpdateBody(t, h.getAs(t, updateOwnerId))["state"] != "ready" {
			t.Error("the card must read Ready to install after the reload")
		}
	})

	t.Run("A bad body is a 400", func(t *testing.T) {
		for _, body := range []string{`{"kind":"upgrade"}`, `{"kind":""}`, `{"kind":7}`, `{"kind":"update"`, `not json`} {
			t.Run(body, func(t *testing.T) {
				h := newRestartHTTP(t)
				h.readyJob()
				h.seedResult(t, update.Result{Outcome: update.OutcomeFailed})

				rec := h.postAsOwner(t, body)

				if rec.Code != http.StatusBadRequest || rec.Body.String() != apperr.BodyErrorMessage+"\n" {
					t.Errorf("status = %d body = %q", rec.Code, rec.Body.String())
				}
				h.assertNoMarkerAndResultKept(t, true)
			})
		}
	})

	t.Run("POST is guarded like the other system routes", func(t *testing.T) {
		cases := []struct {
			name         string
			userId       uint32
			tokenVersion uint32
			status       int
			body         string
		}{
			{"no jwt cookie", 0, 0, http.StatusUnauthorized, ""},
			{"a stale token version", updateOwnerId, 1, http.StatusUnauthorized, apperr.UnauthorizedErrorMessage + "\n"},
			{"an unverified owner", updateUnverifiedOwner, 0, http.StatusForbidden, apperr.VerificationRequiredErrorMessage + "\n"},
			{"an admin", updateAdminId, 0, http.StatusForbidden, apperr.OwnerRequiredErrorMessage + "\n"},
			{"an admin with a bad body", updateAdminId, 0, http.StatusForbidden, apperr.OwnerRequiredErrorMessage + "\n"},
		}
		for _, tc := range cases {
			t.Run(tc.name, func(t *testing.T) {
				h := newRestartHTTP(t)
				h.seedResult(t, update.Result{Outcome: update.OutcomeFailed})
				body := ""
				if strings.Contains(tc.name, "bad body") {
					body = "not json"
				}

				rec := h.post(t, tc.userId, tc.tokenVersion, body)

				if rec.Code != tc.status || (tc.body != "" && rec.Body.String() != tc.body) {
					t.Errorf("status = %d body = %q", rec.Code, rec.Body.String())
				}
				h.assertNoMarkerAndResultKept(t, true)
			})
		}
	})

	t.Run("The checks run in the documented order", func(t *testing.T) {
		h := newRestartHTTP(t)
		h.helper.installed = false

		if rec := h.postAsOwner(t, "not json"); rec.Code != http.StatusBadRequest {
			t.Errorf("a bad body with can_apply off = %d, want 400", rec.Code)
		}
		if rec := h.postAsOwner(t, `{"kind":"update"}`); rec.Code != http.StatusConflict {
			t.Errorf("can_apply off with a mismatching kind = %d, want 409", rec.Code)
		}
	})

	t.Run("Restart is refused with 409", func(t *testing.T) {
		cases := []struct {
			name    string
			prepare func(*restartHTTP, *testing.T)
		}{
			{"can_apply is false (no update-helper.json)", func(h *restartHTTP, _ *testing.T) { h.helper.installed = false }},
			{"the job state is downloading", func(h *restartHTTP, _ *testing.T) {
				h.jobs.put(update.Job{Tag: downloadTag, State: update.StateDownloading})
			}},
			{"the job state is verifying", func(h *restartHTTP, _ *testing.T) {
				h.jobs.put(update.Job{Tag: downloadTag, State: update.StateVerifying})
			}},
			{"a marker is already pending", func(h *restartHTTP, t *testing.T) {
				if err := h.markers.Write(update.RestartRequest{Kind: "restart", RequestedAt: restartBaseTime, RequestedBy: 9}); err != nil {
					t.Fatal(err)
				}
			}},
			{"the result file reads running (helper at work)", func(h *restartHTTP, t *testing.T) {
				h.seedResult(t, update.Result{Outcome: update.OutcomeRunning, Kind: "update", StartedAt: restartBaseTime.Add(-30 * time.Second)})
			}},
		}
		for _, tc := range cases {
			t.Run(tc.name, func(t *testing.T) {
				h := newRestartHTTP(t)
				tc.prepare(h, t)
				markerBefore, markerExisted := h.markerBytes()
				resultBefore, resultExisted := os.ReadFile(h.resultPath)

				rec := h.postAsOwner(t, "")

				markerAfter, markerExistsNow := h.markerBytes()
				resultAfter, resultExistsNow := os.ReadFile(h.resultPath)
				if rec.Code != http.StatusConflict {
					t.Fatalf("status = %d", rec.Code)
				}
				if markerExisted != markerExistsNow || string(markerBefore) != string(markerAfter) || (resultExisted == nil) != (resultExistsNow == nil) || string(resultBefore) != string(resultAfter) {
					t.Error("the existing marker and result must be untouched and no new marker written")
				}
			})
		}
	})

	t.Run("Two restarts at once write one marker", func(t *testing.T) {
		h := newRestartHTTP(t)
		var wait sync.WaitGroup
		codes := make([]int, 2)
		for i, userId := range []uint32{updateOwnerId, updateSecondOwner} {
			wait.Add(1)
			go func() {
				defer wait.Done()
				tokenVersion := uint32(0)
				if userId == updateOwnerId {
					tokenVersion = 2
				}
				codes[i] = h.post(t, userId, tokenVersion, "").Code
			}()
		}
		wait.Wait()

		accepted, refused := 0, 0
		for _, code := range codes {
			switch code {
			case http.StatusAccepted:
				accepted++
			case http.StatusConflict:
				refused++
			}
		}
		entries, _ := os.ReadDir(h.dataDir)
		if accepted != 1 || refused != 1 || len(entries) != 1 {
			t.Errorf("codes = %v, entries = %d", codes, len(entries))
		}
	})

	t.Run("The marker cannot be written", func(t *testing.T) {
		assertFailure := func(t *testing.T, h *restartHTTP) {
			t.Helper()
			jobBefore, _ := h.jobs.Load()
			rec := h.postAsOwner(t, "")
			jobAfter, _ := h.jobs.Load()
			if rec.Code != http.StatusInternalServerError || rec.Body.String() != "Internal server error\n" {
				t.Errorf("status = %d body = %q", rec.Code, rec.Body.String())
			}
			if strings.Contains(rec.Body.String(), h.dataDir) || jobAfter != jobBefore {
				t.Error("no path may leak and the job record must not change")
			}
		}

		t.Run("a directory sits where the marker goes", func(t *testing.T) {
			h := newRestartHTTP(t)
			h.readyJob()
			if err := os.Mkdir(h.markerPath, 0o755); err != nil {
				t.Fatal(err)
			}
			assertFailure(t, h)
			if info, err := os.Stat(h.markerPath); err != nil || !info.IsDir() {
				t.Error("the directory must stay")
			}
		})

		t.Run("the data directory is not writable", func(t *testing.T) {
			if runtime.GOOS == "windows" || os.Geteuid() == 0 {
				t.Skip("directory permissions are not enforced here")
			}
			h := newRestartHTTP(t)
			if err := os.Chmod(h.dataDir, 0o500); err != nil {
				t.Fatal(err)
			}
			defer os.Chmod(h.dataDir, 0o700)
			assertFailure(t, h)
			if _, found := h.markerBytes(); found {
				t.Error("no marker may exist")
			}
		})
	})

	t.Run("GET derives the state from the files and never changes them", func(t *testing.T) {
		finished := restartBaseTime.Add(-10 * time.Second)
		cases := []struct {
			name     string
			files    func(*restartHTTP, *testing.T)
			state    string
			errKind  any
			finished any
		}{
			{"a marker is present", func(h *restartHTTP, t *testing.T) {
				_ = h.markers.Write(update.RestartRequest{Kind: "restart", RequestedAt: restartBaseTime.Add(-time.Second)})
			}, "restarting", nil, nil},
			{"result running written 30 s ago", func(h *restartHTTP, t *testing.T) {
				h.seedResult(t, update.Result{Outcome: "running", Kind: "update", Tag: downloadTag, StartedAt: restartBaseTime.Add(-30 * time.Second)})
			}, "restarting", nil, nil},
			{"result running written 6 minutes ago, no marker", func(h *restartHTTP, t *testing.T) {
				h.seedResult(t, update.Result{Outcome: "running", Kind: "update", Tag: downloadTag, StartedAt: restartBaseTime.Add(-6 * time.Minute), FinishedAt: &finished})
			}, "failed", "install", "2026-09-30T09:49:50Z"},
			{"result succeeded, kind update, tag equal to the running version", func(h *restartHTTP, t *testing.T) {
				h.seedResult(t, update.Result{Outcome: "succeeded", Kind: "update", Tag: updateRunning, StartedAt: restartBaseTime.Add(-time.Minute), FinishedAt: &finished})
			}, "succeeded", nil, "2026-09-30T09:49:50Z"},
			{"result succeeded, kind update, tag older than the running one", func(h *restartHTTP, t *testing.T) {
				h.seedResult(t, update.Result{Outcome: "succeeded", Kind: "update", Tag: "v2.1.0-beta", StartedAt: restartBaseTime.Add(-time.Minute), FinishedAt: &finished})
			}, "idle", nil, "2026-09-30T09:49:50Z"},
			{"result succeeded, kind restart", func(h *restartHTTP, t *testing.T) {
				h.seedResult(t, update.Result{Outcome: "succeeded", Kind: "restart", StartedAt: restartBaseTime.Add(-time.Minute), FinishedAt: &finished})
			}, "idle", nil, "2026-09-30T09:49:50Z"},
			{"result rolled_back", func(h *restartHTTP, t *testing.T) {
				h.seedResult(t, update.Result{Outcome: "rolled_back", Kind: "update", Tag: downloadTag, StartedAt: restartBaseTime.Add(-time.Minute), FinishedAt: &finished})
			}, "failed", "rolled_back", "2026-09-30T09:49:50Z"},
			{"result failed", func(h *restartHTTP, t *testing.T) {
				h.seedResult(t, update.Result{Outcome: "failed", Kind: "update", Tag: downloadTag, StartedAt: restartBaseTime.Add(-time.Minute), FinishedAt: &finished})
			}, "failed", "install", "2026-09-30T09:49:50Z"},
			{"no marker, no result", func(*restartHTTP, *testing.T) {}, "idle", nil, nil},
			{"a corrupt result file", func(h *restartHTTP, t *testing.T) {
				if err := os.WriteFile(h.resultPath, []byte("{not json"), 0o644); err != nil {
					t.Fatal(err)
				}
			}, "idle", nil, nil},
		}
		for _, tc := range cases {
			t.Run(tc.name, func(t *testing.T) {
				h := newRestartHTTP(t)
				tc.files(h, t)
				before := snapshotDirectory(t, h.dataDir)

				first := h.getAs(t, updateAdminId)
				second := h.getAs(t, updateAdminId)

				body := decodeUpdateBody(t, first)
				assertUpdateKeys(t, body)
				if first.Body.String() != second.Body.String() {
					t.Error("two GETs must answer identically")
				}
				if body["state"] != tc.state || body["error"] != tc.errKind || body["finished_at"] != tc.finished {
					t.Errorf("state = %v, error = %v, finished_at = %v", body["state"], body["error"], body["finished_at"])
				}
				if after := snapshotDirectory(t, h.dataDir); !equalSnapshots(before, after) {
					t.Errorf("a GET changed the data directory: %v -> %v", before, after)
				}
			})
		}
	})

	t.Run("After a successful update the status is consistent", func(t *testing.T) {
		h := newRestartHTTP(t)
		h.seedResult(t, update.Result{Outcome: "succeeded", Kind: "update", Tag: updateRunning, StartedAt: restartBaseTime.Add(-time.Minute), FinishedAt: finishedAt(restartBaseTime)})
		h.store.result.Latest = updateRunning

		body := decodeUpdateBody(t, h.getAs(t, updateOwnerId))

		if body["state"] != "succeeded" || body["available"] != false || body["current"] != updateRunning || body["finished_at"] == nil {
			t.Errorf("body = %v", body)
		}
	})
}

type directorySnapshot map[string]string

func snapshotDirectory(t *testing.T, directory string) directorySnapshot {
	t.Helper()
	snapshot := directorySnapshot{}
	entries, err := os.ReadDir(directory)
	if err != nil {
		t.Fatal(err)
	}
	for _, entry := range entries {
		info, _ := entry.Info()
		content, _ := os.ReadFile(filepath.Join(directory, entry.Name()))
		snapshot[entry.Name()] = string(content) + "|" + info.ModTime().String()
	}
	return snapshot
}

func equalSnapshots(a, b directorySnapshot) bool {
	if len(a) != len(b) {
		return false
	}
	for name, value := range a {
		if b[name] != value {
			return false
		}
	}
	return true
}

func TestRestartResultLivesUntilTheNextJob(t *testing.T) {
	t.Run("The result lives until the next job", func(t *testing.T) {
		rig := newDownloadRig(t)
		h := newDownloadHTTP(t, rig)
		rig.results.put(update.Result{Outcome: update.OutcomeRolledBack, Kind: update.RestartKindUpdate, Tag: downloadTag, StartedAt: restartBaseTime, FinishedAt: finishedAt(restartBaseTime)})

		before := decodeUpdateBody(t, h.sendAs(t, http.MethodGet, "/update", updateOwnerId))
		rec := h.sendAs(t, http.MethodPost, downloadPath, updateOwnerId)
		ready := waitForHTTPState(t, h, "ready", "failed")

		if before["state"] != "failed" || before["error"] != "rolled_back" || before["finished_at"] == nil {
			t.Errorf("before = %v", before)
		}
		if rec.Code != http.StatusAccepted || rig.results.deletes != 1 || rig.results.found {
			t.Errorf("status = %d, deletes = %d", rec.Code, rig.results.deletes)
		}
		assertUpdateKeys(t, ready)
		if ready["state"] != "ready" || ready["error"] != nil || ready["finished_at"] != nil {
			t.Errorf("ready = %v", ready)
		}
	})

	t.Run("A download is refused while a restart is pending", func(t *testing.T) {
		rig := newDownloadRig(t)
		h := newDownloadHTTP(t, rig)
		rig.requests.present = true
		rig.results.put(update.Result{Outcome: update.OutcomeRunning, StartedAt: restartBaseTime})

		rec := h.sendAs(t, http.MethodPost, downloadPath, updateOwnerId)

		if rec.Code != http.StatusConflict || rig.results.deletes != 0 || rig.fetcher.totalCalls() != 0 {
			t.Errorf("status = %d", rec.Code)
		}
	})
}

func TestHealthzIsUnchanged(t *testing.T) {
	t.Run("Healthz is unchanged", func(t *testing.T) {
		container := &api.UseCases{
			Token:            jwtauth.New("HS256", []byte("test-secret"), nil),
			OpenMediaUseCase: useCases.NewOpenMediaUseCase(storage.NewLocalStorage(t.TempDir())),
		}
		router := api.InitRoutes(container, config.Settings{Environment: "production"})

		rec := httptest.NewRecorder()
		router.ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/healthz", nil))

		if rec.Code != http.StatusOK || rec.Body.String() != "ok" {
			t.Errorf("status = %d body = %q", rec.Code, rec.Body.String())
		}
		for name := range rec.Header() {
			if strings.Contains(strings.ToLower(name), "version") {
				t.Errorf("unexpected header %s", name)
			}
		}
	})
}

func TestRunningInfoFileAtStartup(t *testing.T) {
	t.Run("The server writes update-running.json at startup", func(t *testing.T) {
		directory := t.TempDir()
		path := filepath.Join(directory, update.RunningInfoFileName)
		store := infraUpdate.NewJSONRunningInfoStore(path)
		first := &fakeClock{now: restartBaseTime}

		if err := useCases.NewRecordRunningInfoUseCase(store, "v2.3.0-beta", 111, first.Now).Record(); err != nil {
			t.Fatal(err)
		}
		content, _ := os.ReadFile(path)
		var written map[string]any
		_ = json.Unmarshal(content, &written)
		if written["version"] != "v2.3.0-beta" || written["pid"] != float64(111) || written["started_at"] != "2026-09-30T09:50:00Z" || len(written) != 3 {
			t.Errorf("file = %s", content)
		}

		later := &fakeClock{now: restartBaseTime.Add(time.Minute)}
		if err := useCases.NewRecordRunningInfoUseCase(store, "v2.3.0-beta", 222, later.Now).Record(); err != nil {
			t.Fatal(err)
		}
		info, found := store.Read()
		if !found || info.Pid != 222 || !info.StartedAt.Equal(later.now) {
			t.Errorf("a second start must replace the file: %+v", info)
		}
		if entries, _ := os.ReadDir(directory); len(entries) != 1 {
			t.Errorf("the temporary file must be renamed away, got %d entries", len(entries))
		}
	})

	t.Run("a write error is returned and nothing panics", func(t *testing.T) {
		store := infraUpdate.NewJSONRunningInfoStore(filepath.Join(t.TempDir(), "missing", update.RunningInfoFileName))

		err := useCases.NewRecordRunningInfoUseCase(store, "v2.3.0-beta", 1, time.Now).Record()

		if err == nil {
			t.Error("the error must reach the startup code")
		}
	})

	t.Run("the file is not served by any route", func(t *testing.T) {
		container := &api.UseCases{
			Token:            jwtauth.New("HS256", []byte("test-secret"), nil),
			OpenMediaUseCase: useCases.NewOpenMediaUseCase(storage.NewLocalStorage(t.TempDir())),
		}
		router := api.InitRoutes(container, config.Settings{Environment: "production"})

		for _, target := range []string{"/update-running.json", "/v1/update-running.json", "/static/uploadedImages/update-running.json"} {
			rec := httptest.NewRecorder()
			router.ServeHTTP(rec, httptest.NewRequest(http.MethodGet, target, nil))
			if rec.Code == http.StatusOK && strings.Contains(rec.Body.String(), "pid") {
				t.Errorf("%s served the file", target)
			}
		}
	})
}