// host_update_test.go — covers POST /api/hosts/{id}/update.
package http

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

	"github.com/coder/websocket"
	"github.com/oklog/ulid/v2"

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

// stubWatcher records Track calls so tests can assert the watcher was
// notified.
type stubWatcher struct {
	mu      sync.Mutex
	tracked []string // hostIDs
}

func (s *stubWatcher) Track(_, hostID string) {
	s.mu.Lock()
	defer s.mu.Unlock()
	s.tracked = append(s.tracked, hostID)
}

func TestHostUpdateHappyPath(t *testing.T) {
	t.Parallel()
	srv, ts, st := rawTestServer(t)
	watcher := &stubWatcher{}
	srv.deps.UpdateWatcher = watcher
	hostID, token := enrolHostForWS(t, srv, st, "upd-host")
	c := agentDial(t, srv, ts, hostID, token)
	sendHello(t, c, "upd-host")
	_ = drainUntil(t, c, api.MsgScheduleSet)

	// Force a version mismatch so the dispatch isn't short-circuited.
	if err := st.MarkHostHello(context.Background(), hostID, "v0", "0.17", api.CurrentProtocolVersion, time.Now().UTC()); err != nil {
		t.Fatalf("mark hello: %v", err)
	}

	cookie := loginAsAdmin(t, st)
	req, _ := stdhttp.NewRequest("POST", ts.URL+"/api/hosts/"+hostID+"/update", 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.StatusAccepted {
		t.Fatalf("status: got %d, want 202", res.StatusCode)
	}
	var out struct {
		JobID string `json:"job_id"`
	}
	if err := json.NewDecoder(res.Body).Decode(&out); err != nil {
		t.Fatalf("decode: %v", err)
	}
	if out.JobID == "" {
		t.Fatal("missing job_id in response")
	}

	// command.update envelope arrives.
	deadline := time.Now().Add(2 * time.Second)
	var got api.Envelope
	for time.Now().Before(deadline) {
		ctx, cancel := context.WithTimeout(context.Background(), 500*time.Millisecond)
		mt, raw, rerr := c.Read(ctx)
		cancel()
		if rerr != nil {
			break
		}
		if mt != websocket.MessageText {
			continue
		}
		if !strings.Contains(string(raw), `"command.update"`) {
			continue
		}
		_ = json.Unmarshal(raw, &got)
		break
	}
	if got.Type != api.MsgCommandUpdate {
		t.Fatal("never received command.update envelope")
	}
	var cp api.CommandUpdatePayload
	if err := got.UnmarshalPayload(&cp); err != nil {
		t.Fatalf("payload: %v", err)
	}
	if cp.JobID != out.JobID {
		t.Fatalf("payload job_id: got %q want %q", cp.JobID, out.JobID)
	}

	// Watcher tracked.
	watcher.mu.Lock()
	defer watcher.mu.Unlock()
	if len(watcher.tracked) != 1 || watcher.tracked[0] != hostID {
		t.Fatalf("watcher tracked: %v", watcher.tracked)
	}

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

func TestHostUpdateNotFound(t *testing.T) {
	t.Parallel()
	_, ts, st := rawTestServer(t)
	cookie := loginAsAdmin(t, st)
	req, _ := stdhttp.NewRequest("POST", ts.URL+"/api/hosts/no-such/update", 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.StatusNotFound {
		t.Fatalf("status: got %d want 404", res.StatusCode)
	}
}

func TestHostUpdateOffline(t *testing.T) {
	t.Parallel()
	_, ts, st := rawTestServer(t)
	hostID := ulid.Make().String()
	if err := st.CreateHost(context.Background(), store.Host{
		ID: hostID, Name: "off", OS: "linux", Arch: "amd64",
		EnrolledAt: time.Now().UTC(),
	}, "deadbeef", ""); err != nil {
		t.Fatalf("create: %v", err)
	}
	cookie := loginAsAdmin(t, st)
	req, _ := stdhttp.NewRequest("POST", ts.URL+"/api/hosts/"+hostID+"/update", 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 != "host_offline" {
		t.Fatalf("code: %q", body.Code)
	}
}

func TestHostUpdateAlreadyUpToDate(t *testing.T) {
	t.Parallel()
	srv, ts, st := rawTestServer(t)
	hostID, token := enrolHostForWS(t, srv, st, "uptodate-host")
	c := agentDial(t, srv, ts, hostID, token)
	sendHello(t, c, "uptodate-host")
	_ = drainUntil(t, c, api.MsgScheduleSet)

	// Force agent_version == version.Version.
	if err := st.MarkHostHello(context.Background(), hostID, version.Version, "0.17", api.CurrentProtocolVersion, time.Now().UTC()); err != nil {
		t.Fatalf("mark hello: %v", err)
	}

	cookie := loginAsAdmin(t, st)
	req, _ := stdhttp.NewRequest("POST", ts.URL+"/api/hosts/"+hostID+"/update", 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 != "already_up_to_date" {
		t.Fatalf("code: %q", body.Code)
	}
}

func TestHostUpdateInProgress(t *testing.T) {
	t.Parallel()
	srv, ts, st := rawTestServer(t)
	hostID, token := enrolHostForWS(t, srv, st, "inprog-host")
	c := agentDial(t, srv, ts, hostID, token)
	sendHello(t, c, "inprog-host")
	_ = drainUntil(t, c, api.MsgScheduleSet)
	if err := st.MarkHostHello(context.Background(), hostID, "v0", "0.17", api.CurrentProtocolVersion, time.Now().UTC()); err != nil {
		t.Fatalf("mark hello: %v", err)
	}

	// Pre-seed an in-flight update job.
	jobID := ulid.Make().String()
	if err := st.CreateJob(context.Background(), store.Job{
		ID: jobID, HostID: hostID, Kind: "update",
		ActorKind: "user", CreatedAt: time.Now().UTC(),
	}); err != nil {
		t.Fatalf("seed job: %v", err)
	}

	cookie := loginAsAdmin(t, st)
	req, _ := stdhttp.NewRequest("POST", ts.URL+"/api/hosts/"+hostID+"/update", 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 != "update_in_progress" {
		t.Fatalf("code: %q", body.Code)
	}
}

func TestHostUpdateRBAC(t *testing.T) {
	t.Parallel()
	_, ts, st := rawTestServer(t)
	hostID := ulid.Make().String()
	if err := st.CreateHost(context.Background(), store.Host{
		ID: hostID, Name: "rbac-host", OS: "linux", Arch: "amd64",
		EnrolledAt: time.Now().UTC(),
	}, "deadbeef", ""); err != nil {
		t.Fatalf("create: %v", err)
	}
	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/hosts/"+hostID+"/update", 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.StatusForbidden {
				t.Fatalf("status for %s: got %d want 403", role, res.StatusCode)
			}
		})
	}
}

type jsonErrBody struct {
	Code    string `json:"code"`
	Message string `json:"message,omitempty"`
}

func readJSONError(t *testing.T, body io.Reader) jsonErrBody {
	t.Helper()
	var out jsonErrBody
	if err := json.NewDecoder(body).Decode(&out); err != nil {
		t.Fatalf("decode error body: %v", err)
	}
	return out
}