// fleet_update_test.go — coverage for the P6-15 fleet-update HTTP
// surface: start/cancel/get JSON endpoints + RBAC.
package http

import (
	"bytes"
	"context"
	"encoding/json"
	stdhttp "net/http"
	"sync"
	"testing"
	"time"

	"github.com/oklog/ulid/v2"

	"gitea.dcglab.co.uk/steve/restic-manager/internal/api"
	"gitea.dcglab.co.uk/steve/restic-manager/internal/server/ws"
	"gitea.dcglab.co.uk/steve/restic-manager/internal/store"
	"gitea.dcglab.co.uk/steve/restic-manager/internal/version"
)

// fakeFleetWorker stands in for *fleetupdate.Worker in HTTP tests.
// It records what was passed to Start/Cancel and lets tests inject
// canned errors. Satisfies the FleetWorker interface in
// host_update.go.
type fakeFleetWorker struct {
	mu sync.Mutex

	startCalls []fakeStartCall
	startID    string
	startErr   error

	cancelCalls []string
	cancelErr   error
}

type fakeStartCall struct {
	UserID  string
	Target  string
	HostIDs []string
}

func (f *fakeFleetWorker) Start(_ context.Context, userID, target string, hostIDs []string) (string, error) {
	f.mu.Lock()
	defer f.mu.Unlock()
	f.startCalls = append(f.startCalls, fakeStartCall{userID, target, append([]string(nil), hostIDs...)})
	if f.startErr != nil {
		return "", f.startErr
	}
	return f.startID, nil
}

func (f *fakeFleetWorker) Cancel(_ context.Context, id string) error {
	f.mu.Lock()
	defer f.mu.Unlock()
	f.cancelCalls = append(f.cancelCalls, id)
	return f.cancelErr
}

// helloOnlineHost is the smallest setup that lets the dispatch /
// derivation logic see a host as "online + version mismatch".
// Returns the host id.
func helloOnlineHost(t *testing.T, srv *Server, st *store.Store, name, agentVer string) string {
	t.Helper()
	id := makeHost(t, st, name)
	if err := st.MarkHostHello(context.Background(), id, agentVer, "0.17", api.CurrentProtocolVersion, time.Now().UTC()); err != nil {
		t.Fatalf("mark hello: %v", err)
	}
	// Mark connected on the hub so deriveOutOfDateOnlineHostIDs
	// considers it online without needing a real WS handshake. The
	// Conn has a nil websocket pointer — tests never call Send on it.
	srv.deps.Hub.Register(id, ws.NewConn(id, nil))
	return id
}

func TestFleetUpdateStartHappyPath(t *testing.T) {
	t.Parallel()
	srv, ts, st := rawTestServer(t)
	worker := &fakeFleetWorker{startID: ulid.Make().String()}
	srv.deps.FleetWorker = worker

	cookie, uid := loginAsAdminWithID(t, st)
	hostID := helloOnlineHost(t, srv, st, "fu-host", "v0")

	body := map[string]any{"host_ids": []string{hostID}}
	raw, _ := json.Marshal(body)
	req, _ := stdhttp.NewRequest("POST", ts.URL+"/api/fleet/update", bytes.NewReader(raw))
	req.AddCookie(cookie)
	req.Header.Set("Content-Type", "application/json")
	res, err := stdhttp.DefaultClient.Do(req)
	if err != nil {
		t.Fatalf("do: %v", err)
	}
	defer res.Body.Close()
	if res.StatusCode != stdhttp.StatusAccepted {
		t.Fatalf("status: got %d, want 202", res.StatusCode)
	}
	var out struct {
		FleetUpdateID string `json:"fleet_update_id"`
	}
	if err := json.NewDecoder(res.Body).Decode(&out); err != nil {
		t.Fatalf("decode: %v", err)
	}
	if out.FleetUpdateID != worker.startID {
		t.Fatalf("fleet_update_id: got %q, want %q", out.FleetUpdateID, worker.startID)
	}
	worker.mu.Lock()
	if len(worker.startCalls) != 1 || worker.startCalls[0].UserID != uid {
		t.Fatalf("start calls: %+v", worker.startCalls)
	}
	if got := worker.startCalls[0].HostIDs; len(got) != 1 || got[0] != hostID {
		t.Fatalf("host_ids: %v", got)
	}
	worker.mu.Unlock()

	// Audit row.
	var n int
	if err := st.DB().QueryRow(
		`SELECT COUNT(*) FROM audit_log WHERE action = 'fleet.update_started' AND target_id = ?`,
		out.FleetUpdateID).Scan(&n); err != nil {
		t.Fatalf("audit count: %v", err)
	}
	if n != 1 {
		t.Fatalf("audit rows: got %d, want 1", n)
	}
}

func TestFleetUpdateStartConflictWhenAlreadyRunning(t *testing.T) {
	t.Parallel()
	srv, ts, st := rawTestServer(t)
	worker := &fakeFleetWorker{startErr: store.ErrFleetUpdateRunning}
	srv.deps.FleetWorker = worker
	cookie := loginAsAdmin(t, st)
	_ = helloOnlineHost(t, srv, st, "fu-host", "v0")

	req, _ := stdhttp.NewRequest("POST", ts.URL+"/api/fleet/update", bytes.NewReader([]byte(`{}`)))
	req.AddCookie(cookie)
	req.Header.Set("Content-Type", "application/json")
	res, err := stdhttp.DefaultClient.Do(req)
	if err != nil {
		t.Fatalf("do: %v", err)
	}
	defer res.Body.Close()
	if res.StatusCode != stdhttp.StatusConflict {
		t.Fatalf("status: got %d, want 409", res.StatusCode)
	}
	body := readJSONError(t, res.Body)
	if body.Code != "fleet_update_in_progress" {
		t.Fatalf("code: %q", body.Code)
	}
}

func TestFleetUpdateStartDerivesHostIDsWhenEmpty(t *testing.T) {
	t.Parallel()
	srv, ts, st := rawTestServer(t)
	worker := &fakeFleetWorker{startID: ulid.Make().String()}
	srv.deps.FleetWorker = worker
	cookie := loginAsAdmin(t, st)

	// Two online + out-of-date, one online + at-target, one offline.
	a := helloOnlineHost(t, srv, st, "behind-a", "v0")
	b := helloOnlineHost(t, srv, st, "behind-b", "v0")
	_ = helloOnlineHost(t, srv, st, "uptodate", version.Version)
	offlineID := makeHost(t, st, "offline-host")
	if err := st.MarkHostHello(context.Background(), offlineID, "v0", "0.17", api.CurrentProtocolVersion, time.Now().UTC()); err != nil {
		t.Fatalf("mark hello: %v", err)
	}
	// Don't MarkOnline → derivation should skip.

	req, _ := stdhttp.NewRequest("POST", ts.URL+"/api/fleet/update", bytes.NewReader([]byte(`{}`)))
	req.AddCookie(cookie)
	req.Header.Set("Content-Type", "application/json")
	res, err := stdhttp.DefaultClient.Do(req)
	if err != nil {
		t.Fatalf("do: %v", err)
	}
	defer res.Body.Close()
	if res.StatusCode != stdhttp.StatusAccepted {
		t.Fatalf("status: got %d, want 202", res.StatusCode)
	}
	worker.mu.Lock()
	defer worker.mu.Unlock()
	if len(worker.startCalls) != 1 {
		t.Fatalf("start calls: %d", len(worker.startCalls))
	}
	got := worker.startCalls[0].HostIDs
	want := map[string]bool{a: true, b: true}
	if len(got) != 2 || !want[got[0]] || !want[got[1]] {
		t.Fatalf("derived host_ids: got %v, want both of %v", got, []string{a, b})
	}
}

func TestFleetUpdateCancelHappyPath(t *testing.T) {
	t.Parallel()
	srv, ts, st := rawTestServer(t)
	worker := &fakeFleetWorker{}
	srv.deps.FleetWorker = worker
	cookie := loginAsAdmin(t, st)

	// Seed a running fleet update directly.
	fuID := ulid.Make().String()
	uid := ulid.Make().String()
	if err := st.CreateUser(context.Background(), store.User{
		ID: uid, Username: "starter", PasswordHash: "x",
		Role: store.RoleAdmin, CreatedAt: time.Now().UTC(),
	}); err != nil {
		t.Fatalf("seed user: %v", err)
	}
	hostID := makeHost(t, st, "fu-cancel-host")
	if err := st.CreateFleetUpdate(context.Background(),
		store.FleetUpdate{ID: fuID, StartedByUserID: uid, TargetVersion: "v1"},
		[]string{hostID}); err != nil {
		t.Fatalf("seed fleet update: %v", err)
	}

	req, _ := stdhttp.NewRequest("POST", ts.URL+"/api/fleet-updates/"+fuID+"/cancel", nil)
	req.AddCookie(cookie)
	res, err := stdhttp.DefaultClient.Do(req)
	if err != nil {
		t.Fatalf("do: %v", err)
	}
	defer res.Body.Close()
	if res.StatusCode != stdhttp.StatusNoContent {
		t.Fatalf("status: got %d, want 204", res.StatusCode)
	}
	worker.mu.Lock()
	if len(worker.cancelCalls) != 1 || worker.cancelCalls[0] != fuID {
		t.Fatalf("cancel calls: %v", worker.cancelCalls)
	}
	worker.mu.Unlock()
}

func TestFleetUpdateCancelNotRunning(t *testing.T) {
	t.Parallel()
	srv, ts, st := rawTestServer(t)
	srv.deps.FleetWorker = &fakeFleetWorker{}
	cookie := loginAsAdmin(t, st)

	// Seed + complete one so it's no longer running.
	fuID := ulid.Make().String()
	uid := ulid.Make().String()
	_ = st.CreateUser(context.Background(), store.User{
		ID: uid, Username: "starter2", PasswordHash: "x",
		Role: store.RoleAdmin, CreatedAt: time.Now().UTC(),
	})
	hostID := makeHost(t, st, "fu-done-host")
	_ = st.CreateFleetUpdate(context.Background(),
		store.FleetUpdate{ID: fuID, StartedByUserID: uid, TargetVersion: "v1"},
		[]string{hostID})
	if err := st.CompleteFleetUpdate(context.Background(), fuID, time.Now().UTC()); err != nil {
		t.Fatalf("complete: %v", err)
	}

	req, _ := stdhttp.NewRequest("POST", ts.URL+"/api/fleet-updates/"+fuID+"/cancel", nil)
	req.AddCookie(cookie)
	res, err := stdhttp.DefaultClient.Do(req)
	if err != nil {
		t.Fatalf("do: %v", err)
	}
	defer res.Body.Close()
	if res.StatusCode != stdhttp.StatusConflict {
		t.Fatalf("status: got %d, want 409", res.StatusCode)
	}
	body := readJSONError(t, res.Body)
	if body.Code != "fleet_update_not_running" {
		t.Fatalf("code: %q", body.Code)
	}
}

func TestFleetUpdateGetHydrates(t *testing.T) {
	t.Parallel()
	_, ts, st := rawTestServer(t)
	cookie := loginAsAdmin(t, st)

	uid := ulid.Make().String()
	_ = st.CreateUser(context.Background(), store.User{
		ID: uid, Username: "starter3", PasswordHash: "x",
		Role: store.RoleAdmin, CreatedAt: time.Now().UTC(),
	})
	hostID := makeHost(t, st, "fu-get-host")
	fuID := ulid.Make().String()
	if err := st.CreateFleetUpdate(context.Background(),
		store.FleetUpdate{ID: fuID, StartedByUserID: uid, TargetVersion: "v1.2.3"},
		[]string{hostID}); err != nil {
		t.Fatalf("seed: %v", err)
	}

	req, _ := stdhttp.NewRequest("GET", ts.URL+"/api/fleet-updates/"+fuID, nil)
	req.AddCookie(cookie)
	res, err := stdhttp.DefaultClient.Do(req)
	if err != nil {
		t.Fatalf("do: %v", err)
	}
	defer res.Body.Close()
	if res.StatusCode != stdhttp.StatusOK {
		t.Fatalf("status: got %d, want 200", res.StatusCode)
	}
	var got fleetUpdateView
	if err := json.NewDecoder(res.Body).Decode(&got); err != nil {
		t.Fatalf("decode: %v", err)
	}
	if got.ID != fuID || got.TargetVersion != "v1.2.3" || got.Status != "running" {
		t.Fatalf("parent: %+v", got)
	}
	if len(got.Hosts) != 1 || got.Hosts[0].HostID != hostID || got.Hosts[0].HostName != "fu-get-host" {
		t.Fatalf("hosts: %+v", got.Hosts)
	}
}

func TestFleetUpdateRBAC(t *testing.T) {
	t.Parallel()
	_, ts, st := rawTestServer(t)

	for _, role := range []store.Role{store.RoleViewer, store.RoleOperator} {
		role := role
		t.Run(string(role), func(t *testing.T) {
			cookie := loginAsRole(t, st, role)
			req, _ := stdhttp.NewRequest("POST", ts.URL+"/api/fleet/update", bytes.NewReader([]byte(`{}`)))
			req.AddCookie(cookie)
			req.Header.Set("Content-Type", "application/json")
			res, err := stdhttp.DefaultClient.Do(req)
			if err != nil {
				t.Fatalf("do: %v", err)
			}
			defer res.Body.Close()
			if res.StatusCode != stdhttp.StatusForbidden {
				t.Fatalf("status: got %d, want 403", res.StatusCode)
			}
		})
	}
}

// Sanity check that fakeFleetWorker satisfies the FleetWorker iface.
var _ FleetWorker = (*fakeFleetWorker)(nil)