feat(web): registration gate + per-request user-id seam (ADR-012)

Multi-user web surface. Two layered middlewares: Auth.Middleware (Dex
session required) wraps registrationGate, which resolves the authenticated
subject -> tapir user_id once per request via the new web.Identity port and
stashes it. A subject with no tapir user is redirected to GET /register
(display name + accept-terms); POST /register calls RegisterUser then
redirects to /. /register is inside the auth guard but exempt from the gate
(/auth/* and /healthz too).

Current-user seam: CurrentUserID(r) (string, bool) returns the resolved id
from the request context. The list/detail/action handlers now scope by it,
replacing the single configured App.UserID (removed). App gains an Identity
field; *store.Store satisfies both Store and Identity. cmd/tapir wires
Identity: st and drops UserID.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

internal/web/handlers.go

@@ -23,15 +23,16 @@ type Store interface {
 	ClearAction(ctx context.Context, userID, videoID, action string) error
 }
 
-// App is the Stage-0 web surface: handlers over the store, gated by an Auth
-// implementation. UserID is the single configured tapir user every store
-// operation runs as (ADR-011 — Auth only gates access; it does not select the
-// store identity).
+// App is the Stage-1 web surface: handlers over the store, gated by an Auth
+// implementation (authentication) and a registration gate (which resolves the
+// authenticated subject to its tapir user_id and stashes it per request). Every
+// data handler scopes by that resolved id — CurrentUserID(r) — not by a single
+// configured user (ADR-012, multi-user with enforced isolation).
 type App struct {
-	Store  Store
-	Auth   Auth
-	UserID string
-	Log    *slog.Logger
+	Store    Store
+	Identity Identity
+	Auth     Auth
+	Log      *slog.Logger
 }
 
 func (a *App) logger() *slog.Logger {
@@ -54,8 +55,14 @@ func (a *App) Router() http.Handler {
 	app.HandleFunc("GET /{$}", a.handleList)
 	app.HandleFunc("GET /v/{videoId}", a.handleDetail)
 	app.HandleFunc("POST /v/{videoId}/action", a.handleAction)
+	app.HandleFunc("GET /register", a.handleRegisterForm)
+	app.HandleFunc("POST /register", a.handleRegister)
 
-	root.Handle("/", a.Auth.Middleware(app))
+	// Two layers: Auth.Middleware requires a Dex session (you must be logged in);
+	// registrationGate requires a tapir user (else → /register) and stashes the
+	// resolved user_id. /register lives inside the auth guard but is exempt from
+	// the registration gate (you must be able to reach it before you have a user).
+	root.Handle("/", a.Auth.Middleware(a.registrationGate(app)))
 	return root
 }
 
@@ -69,6 +76,10 @@ func (a *App) handleHealthz(w http.ResponseWriter, _ *http.Request) {
 // query string. An HTMX request gets only the table fragment so the filter form
 // can swap #summary-list in place; a plain request gets the full page.
 func (a *App) handleList(w http.ResponseWriter, r *http.Request) {
+	userID, ok := a.currentUserID(w, r)
+	if !ok {
+		return
+	}
 	q := r.URL.Query()
 	f := Filter{
 		Channel: q.Get("channel"),
@@ -76,7 +87,7 @@ func (a *App) handleList(w http.ResponseWriter, r *http.Request) {
 		To:      q.Get("to"),
 	}
 
-	rows, err := a.Store.ListSummaries(r.Context(), a.UserID, 0)
+	rows, err := a.Store.ListSummaries(r.Context(), userID, 0)
 	if err != nil {
 		a.serverError(w, r, "list summaries", err)
 		return
@@ -92,8 +103,12 @@ func (a *App) handleList(w http.ResponseWriter, r *http.Request) {
 
 // handleDetail renders one summary in full (highlights, takeaways, action group).
 func (a *App) handleDetail(w http.ResponseWriter, r *http.Request) {
+	userID, ok := a.currentUserID(w, r)
+	if !ok {
+		return
+	}
 	videoID := r.PathValue("videoId")
-	row, err := a.Store.GetSummaryByVideo(r.Context(), a.UserID, videoID)
+	row, err := a.Store.GetSummaryByVideo(r.Context(), userID, videoID)
 	if errors.Is(err, store.ErrNotFound) {
 		http.NotFound(w, r)
 		return
@@ -110,6 +125,10 @@ func (a *App) handleDetail(w http.ResponseWriter, r *http.Request) {
 // the refreshed button-group fragment for HTMX; without JS it redirects back to
 // the detail page (POST→redirect→GET).
 func (a *App) handleAction(w http.ResponseWriter, r *http.Request) {
+	userID, ok := a.currentUserID(w, r)
+	if !ok {
+		return
+	}
 	videoID := r.PathValue("videoId")
 	action := r.FormValue("action")
 	if !isActionVerb(action) {
@@ -117,23 +136,23 @@ func (a *App) handleAction(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	current, err := a.Store.ActionsFor(r.Context(), a.UserID, []string{videoID})
+	current, err := a.Store.ActionsFor(r.Context(), userID, []string{videoID})
 	if err != nil {
 		a.serverError(w, r, "read actions", err)
 		return
 	}
 
 	if actionSet(current[videoID])[action] {
-		err = a.Store.ClearAction(r.Context(), a.UserID, videoID, action)
+		err = a.Store.ClearAction(r.Context(), userID, videoID, action)
 	} else {
-		err = a.Store.SetAction(r.Context(), a.UserID, videoID, action)
+		err = a.Store.SetAction(r.Context(), userID, videoID, action)
 	}
 	if err != nil {
 		a.serverError(w, r, "toggle action", err)
 		return
 	}
 
-	updated, err := a.Store.ActionsFor(r.Context(), a.UserID, []string{videoID})
+	updated, err := a.Store.ActionsFor(r.Context(), userID, []string{videoID})
 	if err != nil {
 		a.serverError(w, r, "read actions", err)
 		return
@@ -146,10 +165,29 @@ func (a *App) handleAction(w http.ResponseWriter, r *http.Request) {
 	http.Redirect(w, r, "/v/"+videoID, http.StatusSeeOther)
 }
 
+// currentUserID returns the tapir user_id the registration gate resolved for this
+// request. Behind the gate it is always present; a miss means a handler was
+// reached without scoping (a wiring bug), so it answers 500 and reports false.
+func (a *App) currentUserID(w http.ResponseWriter, r *http.Request) (string, bool) {
+	id, ok := CurrentUserID(r)
+	if !ok {
+		a.serverError(w, r, "current user", errNoCurrentUser)
+	}
+	return id, ok
+}
+
 // render writes a templ component as HTML. A render error is logged, not retried:
 // headers may already be flushed, so there is nothing useful to send the client.
 func (a *App) render(w http.ResponseWriter, r *http.Request, c templ.Component) {
+	a.renderStatus(w, r, http.StatusOK, c)
+}
+
+// renderStatus writes a templ component as HTML with an explicit status code (the
+// Content-Type must be set before WriteHeader, so this is the single place that
+// orders them correctly).
+func (a *App) renderStatus(w http.ResponseWriter, r *http.Request, status int, c templ.Component) {
 	w.Header().Set("Content-Type", "text/html; charset=utf-8")
+	w.WriteHeader(status)
 	if err := c.Render(r.Context(), w); err != nil {
 		a.logger().Error("render", "path", r.URL.Path, "err", err)
 	}

internal/web/handlers_test.go

@@ -45,6 +45,9 @@ const (
 	userID = "11111111-1111-1111-1111-111111111111"
 	videoX = "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"
 	videoY = "bbbbbbbb-bbbb-bbbb-bbbb-bbbbbbbbbbbb"
+	// stubSubject is the StubAuth Dex subject the registration gate resolves to
+	// the fixed userID (mapping seeded by resetDB).
+	stubSubject = "stub-subject-xyz"
 )
 
 func newStore(t *testing.T) *store.Store {
@@ -63,21 +66,48 @@ func rawPool(t *testing.T) *pgxpool.Pool {
 	return p
 }
 
-func resetDB(t *testing.T, p *pgxpool.Pool) {
+// truncateAll wipes every table to a pristine state (user_identities is cleared
+// via the ON DELETE CASCADE from users). Registration tests use this directly so
+// no subject is pre-registered.
+func truncateAll(t *testing.T, p *pgxpool.Pool) {
 	t.Helper()
 	_, err := p.Exec(context.Background(),
 		`TRUNCATE summary_actions, sink_deliveries, summaries, transcripts, videos, users CASCADE`)
 	require.NoError(t, err)
 }
 
-// newApp builds the App under test: the real store, StubAuth (allow-all) keyed to
-// the configured user. This is exactly cmd/tapir's serve wiring minus Dex.
+// resetDB truncates, then seeds the StubAuth identity (stubSubject → userID) so
+// the registration gate resolves the stub user and the existing handler tests can
+// keep seeding and scoping by the fixed userID.
+func resetDB(t *testing.T, p *pgxpool.Pool) {
+	t.Helper()
+	truncateAll(t, p)
+	ctx := context.Background()
+	_, err := p.Exec(ctx, `INSERT INTO users (id) VALUES ($1) ON CONFLICT (id) DO NOTHING`, userID)
+	require.NoError(t, err)
+	_, err = p.Exec(ctx,
+		`INSERT INTO user_identities (dex_subject, user_id) VALUES ($1, $2)
+		 ON CONFLICT (dex_subject) DO NOTHING`, stubSubject, userID)
+	require.NoError(t, err)
+}
+
+// newApp builds the App under test as the registered stub user (subject
+// stubSubject, resolved to userID by resetDB). This is cmd/tapir's serve wiring
+// minus Dex: the store is both the Store and the Identity port.
 func newApp(t *testing.T) *web.App {
 	t.Helper()
+	return newAppAs(t, stubSubject)
+}
+
+// newAppAs builds the App under test with a specific StubAuth Dex subject, so
+// registration-gate tests can drive registered vs unregistered subjects.
+func newAppAs(t *testing.T, subject string) *web.App {
+	t.Helper()
+	s := newStore(t)
 	return &web.App{
-		Store:  newStore(t),
-		Auth:   web.StubAuth{U: web.User{Subject: userID}},
-		UserID: userID,
+		Store:    s,
+		Identity: s,
+		Auth:     web.StubAuth{U: web.User{Subject: subject}},
 	}
 }
 

internal/web/register_test.go

@@ -0,0 +1,86 @@
+package web_test
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestUnregisteredSubjectRedirectedToRegister(t *testing.T) {
+	app := newAppAs(t, "unregistered-sub")
+	truncateAll(t, rawPool(t))
+
+	rec := do(t, app, httptest.NewRequest(http.MethodGet, "/", nil))
+	require.Equal(t, http.StatusFound, rec.Code)
+	require.Equal(t, "/register", rec.Header().Get("Location"))
+}
+
+func TestRegisterPageReachableWhenUnregistered(t *testing.T) {
+	app := newAppAs(t, "unregistered-sub")
+	truncateAll(t, rawPool(t))
+
+	rec := do(t, app, httptest.NewRequest(http.MethodGet, "/register", nil))
+	require.Equal(t, http.StatusOK, rec.Code, "/register is exempt from the gate")
+	require.Contains(t, body(t, rec), "Complete your registration")
+}
+
+func TestRegisteredSubjectPassesThrough(t *testing.T) {
+	app := newApp(t) // stubSubject
+	resetDB(t, rawPool(t))
+
+	rec := do(t, app, httptest.NewRequest(http.MethodGet, "/", nil))
+	require.Equal(t, http.StatusOK, rec.Code)
+	require.Contains(t, body(t, rec), "<html", "registered subject gets the app, not a redirect")
+}
+
+func TestRegisterCreatesExactlyOneUserAndIdentity(t *testing.T) {
+	ctx := context.Background()
+	const sub = "brand-new-subject"
+	app := newAppAs(t, sub)
+	p := rawPool(t)
+	truncateAll(t, p)
+
+	req := httptest.NewRequest(http.MethodPost, "/register",
+		strings.NewReader("display_name=Newbie&accept_terms=yes"))
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	rec := do(t, app, req)
+	require.Equal(t, http.StatusSeeOther, rec.Code)
+	require.Equal(t, "/", rec.Header().Get("Location"))
+
+	// Exactly one identity row for the subject, and its user exists.
+	var idents int
+	var newID string
+	require.NoError(t, p.QueryRow(ctx,
+		`SELECT count(*), coalesce(max(user_id::text), '') FROM user_identities WHERE dex_subject = $1`,
+		sub).Scan(&idents, &newID))
+	require.Equal(t, 1, idents)
+
+	var users int
+	require.NoError(t, p.QueryRow(ctx, `SELECT count(*) FROM users WHERE id = $1`, newID).Scan(&users))
+	require.Equal(t, 1, users)
+
+	// Returning subject resolves straight through — no second user created.
+	rec = do(t, app, httptest.NewRequest(http.MethodGet, "/", nil))
+	require.Equal(t, http.StatusOK, rec.Code)
+
+	var totalUsers, totalIdents int
+	require.NoError(t, p.QueryRow(ctx, `SELECT count(*) FROM users`).Scan(&totalUsers))
+	require.NoError(t, p.QueryRow(ctx, `SELECT count(*) FROM user_identities`).Scan(&totalIdents))
+	require.Equal(t, 1, totalUsers, "a second request must not register again")
+	require.Equal(t, 1, totalIdents)
+}
+
+func TestRegisterRejectsMissingFields(t *testing.T) {
+	app := newAppAs(t, "incomplete-subject")
+	truncateAll(t, rawPool(t))
+
+	req := httptest.NewRequest(http.MethodPost, "/register",
+		strings.NewReader("display_name=&accept_terms=")) // both missing
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	rec := do(t, app, req)
+	require.Equal(t, http.StatusBadRequest, rec.Code)
+}

internal/web/registration.go

@@ -0,0 +1,132 @@
+package web
+
+import (
+	"context"
+	"errors"
+	"net/http"
+	"strings"
+)
+
+// Identity is the narrow port the web layer uses to resolve a Dex subject to a
+// tapir user and to register new ones (ADR-012). *store.Store satisfies it; tests
+// can substitute a fake. It is deliberately separate from Store: identity
+// resolution runs pre-scope (un-RLS'd map), whereas Store runs user-scoped.
+type Identity interface {
+	UserBySubject(ctx context.Context, subject string) (userID string, found bool, err error)
+	RegisterUser(ctx context.Context, subject, displayName string) (userID string, err error)
+}
+
+// errNoCurrentUser indicates a scoped handler ran without a resolved user_id —
+// only possible if it was reached outside the registration gate (a wiring bug).
+var errNoCurrentUser = errors.New("web: no current user in request context")
+
+// userIDCtxKey types the per-request resolved tapir user_id stored by the
+// registration gate. Unexported so only this package can set it.
+type userIDCtxKey struct{}
+
+func withUserID(ctx context.Context, id string) context.Context {
+	return context.WithValue(ctx, userIDCtxKey{}, id)
+}
+
+// CurrentUserID returns the tapir user_id (UUID) the registration gate resolved
+// for the request from the authenticated Dex subject. ok is false for requests
+// that never passed the gate (e.g. /register, /auth/*). This is the seam handlers
+// — and downstream features (per-user YouTube connect, account management) —
+// scope every store access by.
+func CurrentUserID(r *http.Request) (string, bool) {
+	id, ok := r.Context().Value(userIDCtxKey{}).(string)
+	return id, ok && id != ""
+}
+
+// registrationGate sits inside Auth.Middleware. For a gated request it resolves
+// the authenticated subject → tapir user_id once and stashes it for handlers; a
+// subject with no tapir user is redirected to /register. Exempt paths pass
+// straight through (/register so an unregistered user can reach the form; /auth/*
+// and /healthz are already public but listed for safety).
+func (a *App) registrationGate(h http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if isRegistrationExempt(r.URL.Path) {
+			h.ServeHTTP(w, r)
+			return
+		}
+		user, ok := a.Auth.CurrentUser(r)
+		if !ok {
+			// Auth.Middleware should have caught this; redirect defensively.
+			http.Redirect(w, r, loginPath, http.StatusFound)
+			return
+		}
+		userID, found, err := a.Identity.UserBySubject(r.Context(), user.Subject)
+		if err != nil {
+			a.serverError(w, r, "resolve identity", err)
+			return
+		}
+		if !found {
+			http.Redirect(w, r, registerPath, http.StatusFound)
+			return
+		}
+		h.ServeHTTP(w, r.WithContext(withUserID(r.Context(), userID)))
+	})
+}
+
+// handleRegisterForm renders the registration form for an authenticated, not-yet-
+// registered subject. An already-registered subject is sent to the app root.
+func (a *App) handleRegisterForm(w http.ResponseWriter, r *http.Request) {
+	user, ok := a.Auth.CurrentUser(r)
+	if !ok {
+		http.Redirect(w, r, loginPath, http.StatusFound)
+		return
+	}
+	if _, found, err := a.Identity.UserBySubject(r.Context(), user.Subject); err != nil {
+		a.serverError(w, r, "resolve identity", err)
+		return
+	} else if found {
+		http.Redirect(w, r, "/", http.StatusSeeOther)
+		return
+	}
+	a.render(w, r, RegisterPage(user.Email, ""))
+}
+
+// handleRegister creates the tapir user for the authenticated subject from the
+// submitted display name (terms must be accepted), then redirects to the app
+// root. A double-submit by an already-registered subject is idempotent.
+func (a *App) handleRegister(w http.ResponseWriter, r *http.Request) {
+	user, ok := a.Auth.CurrentUser(r)
+	if !ok {
+		http.Redirect(w, r, loginPath, http.StatusFound)
+		return
+	}
+	if _, found, err := a.Identity.UserBySubject(r.Context(), user.Subject); err != nil {
+		a.serverError(w, r, "resolve identity", err)
+		return
+	} else if found {
+		http.Redirect(w, r, "/", http.StatusSeeOther)
+		return
+	}
+
+	if err := r.ParseForm(); err != nil {
+		http.Error(w, "bad form", http.StatusBadRequest)
+		return
+	}
+	displayName := strings.TrimSpace(r.FormValue("display_name"))
+	accepted := r.FormValue("accept_terms") != ""
+	if displayName == "" || !accepted {
+		a.renderStatus(w, r, http.StatusBadRequest,
+			RegisterPage(user.Email, "Enter a display name and accept the terms to continue."))
+		return
+	}
+
+	if _, err := a.Identity.RegisterUser(r.Context(), user.Subject, displayName); err != nil {
+		a.serverError(w, r, "register user", err)
+		return
+	}
+	http.Redirect(w, r, "/", http.StatusSeeOther)
+}
+
+const (
+	registerPath = "/register"
+	loginPath    = "/auth/login"
+)
+
+func isRegistrationExempt(p string) bool {
+	return p == registerPath || p == "/healthz" || strings.HasPrefix(p, "/auth/")
+}

internal/web/views.templ

@@ -153,6 +153,35 @@ templ DetailPage(r store.SummaryRow) {
 	}
 }
 
+// RegisterPage is the explicit registration step (ADR-012): an authenticated Dex
+// subject with no tapir user picks a display name and accepts the terms to create
+// their account. errMsg, when set, reports a validation problem on the prior POST.
+templ RegisterPage(email, errMsg string) {
+	@Layout("Tapir — Register") {
+		<article class="register">
+			<h1>Complete your registration</h1>
+			if email != "" {
+				<p class="meta">Signed in as { email }.</p>
+			}
+			<p>Choose a display name to finish setting up your Tapir account.</p>
+			if errMsg != "" {
+				<p class="error" role="alert">{ errMsg }</p>
+			}
+			<form method="post" action="/register" class="register-form">
+				<label>
+					Display name
+					<input type="text" name="display_name" required autofocus/>
+				</label>
+				<label class="checkbox">
+					<input type="checkbox" name="accept_terms" value="yes" required/>
+					I accept the terms of use
+				</label>
+				<button type="submit" class="btn">Register</button>
+			</form>
+		</article>
+	}
+}
+
 // ActionButtons is the toggle group fragment returned by POST /v/{id}/action.
 // Each button submits its verb; HTMX swaps this element in place (outerHTML),
 // and without JS the form POSTs and the handler redirects back to the detail

internal/web/views_templ.go

@@ -595,11 +595,10 @@ func DetailPage(r store.SummaryRow) templ.Component {
 	})
 }
 
-// ActionButtons is the toggle group fragment returned by POST /v/{id}/action.
-// Each button submits its verb; HTMX swaps this element in place (outerHTML),
-// and without JS the form POSTs and the handler redirects back to the detail
-// page. active marks the verbs currently set for (user, video).
-func ActionButtons(videoID string, active map[string]bool) templ.Component {
+// RegisterPage is the explicit registration step (ADR-012): an authenticated Dex
+// subject with no tapir user picks a display name and accepts the terms to create
+// their account. errMsg, when set, reports a validation problem on the prior POST.
+func RegisterPage(email, errMsg string) templ.Component {
 	return templruntime.GeneratedTemplate(func(templ_7745c5c3_Input templruntime.GeneratedComponentInput) (templ_7745c5c3_Err error) {
 		templ_7745c5c3_W, ctx := templ_7745c5c3_Input.Writer, templ_7745c5c3_Input.Context
 		if templ_7745c5c3_CtxErr := ctx.Err(); templ_7745c5c3_CtxErr != nil {
@@ -620,112 +619,209 @@ func ActionButtons(videoID string, active map[string]bool) templ.Component {
 			templ_7745c5c3_Var26 = templ.NopComponent
 		}
 		ctx = templ.ClearChildren(ctx)
-		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 50, "<form id=\"action-buttons\" class=\"actions\" method=\"post\" action=\"")
+		templ_7745c5c3_Var27 := templruntime.GeneratedTemplate(func(templ_7745c5c3_Input templruntime.GeneratedComponentInput) (templ_7745c5c3_Err error) {
+			templ_7745c5c3_W, ctx := templ_7745c5c3_Input.Writer, templ_7745c5c3_Input.Context
+			templ_7745c5c3_Buffer, templ_7745c5c3_IsBuffer := templruntime.GetBuffer(templ_7745c5c3_W)
+			if !templ_7745c5c3_IsBuffer {
+				defer func() {
+					templ_7745c5c3_BufErr := templruntime.ReleaseBuffer(templ_7745c5c3_Buffer)
+					if templ_7745c5c3_Err == nil {
+						templ_7745c5c3_Err = templ_7745c5c3_BufErr
+					}
+				}()
+			}
+			ctx = templ.InitializeContext(ctx)
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 50, "<article class=\"register\"><h1>Complete your registration</h1>")
+			if templ_7745c5c3_Err != nil {
+				return templ_7745c5c3_Err
+			}
+			if email != "" {
+				templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 51, "<p class=\"meta\">Signed in as ")
+				if templ_7745c5c3_Err != nil {
+					return templ_7745c5c3_Err
+				}
+				var templ_7745c5c3_Var28 string
+				templ_7745c5c3_Var28, templ_7745c5c3_Err = templ.JoinStringErrs(email)
+				if templ_7745c5c3_Err != nil {
+					return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 164, Col: 40}
+				}
+				_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ.EscapeString(templ_7745c5c3_Var28))
+				if templ_7745c5c3_Err != nil {
+					return templ_7745c5c3_Err
+				}
+				templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 52, ".</p>")
+				if templ_7745c5c3_Err != nil {
+					return templ_7745c5c3_Err
+				}
+			}
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 53, "<p>Choose a display name to finish setting up your Tapir account.</p>")
+			if templ_7745c5c3_Err != nil {
+				return templ_7745c5c3_Err
+			}
+			if errMsg != "" {
+				templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 54, "<p class=\"error\" role=\"alert\">")
+				if templ_7745c5c3_Err != nil {
+					return templ_7745c5c3_Err
+				}
+				var templ_7745c5c3_Var29 string
+				templ_7745c5c3_Var29, templ_7745c5c3_Err = templ.JoinStringErrs(errMsg)
+				if templ_7745c5c3_Err != nil {
+					return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 168, Col: 42}
+				}
+				_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ.EscapeString(templ_7745c5c3_Var29))
+				if templ_7745c5c3_Err != nil {
+					return templ_7745c5c3_Err
+				}
+				templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 55, "</p>")
+				if templ_7745c5c3_Err != nil {
+					return templ_7745c5c3_Err
+				}
+			}
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 56, "<form method=\"post\" action=\"/register\" class=\"register-form\"><label>Display name <input type=\"text\" name=\"display_name\" required autofocus></label> <label class=\"checkbox\"><input type=\"checkbox\" name=\"accept_terms\" value=\"yes\" required> I accept the terms of use</label> <button type=\"submit\" class=\"btn\">Register</button></form></article>")
+			if templ_7745c5c3_Err != nil {
+				return templ_7745c5c3_Err
+			}
+			return nil
+		})
+		templ_7745c5c3_Err = Layout("Tapir — Register").Render(templ.WithChildren(ctx, templ_7745c5c3_Var27), templ_7745c5c3_Buffer)
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}
-		var templ_7745c5c3_Var27 templ.SafeURL
-		templ_7745c5c3_Var27, templ_7745c5c3_Err = templ.JoinURLErrs(actionURL(videoID))
-		if templ_7745c5c3_Err != nil {
-			return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 165, Col: 29}
+		return nil
+	})
+}
+
+// ActionButtons is the toggle group fragment returned by POST /v/{id}/action.
+// Each button submits its verb; HTMX swaps this element in place (outerHTML),
+// and without JS the form POSTs and the handler redirects back to the detail
+// page. active marks the verbs currently set for (user, video).
+func ActionButtons(videoID string, active map[string]bool) templ.Component {
+	return templruntime.GeneratedTemplate(func(templ_7745c5c3_Input templruntime.GeneratedComponentInput) (templ_7745c5c3_Err error) {
+		templ_7745c5c3_W, ctx := templ_7745c5c3_Input.Writer, templ_7745c5c3_Input.Context
+		if templ_7745c5c3_CtxErr := ctx.Err(); templ_7745c5c3_CtxErr != nil {
+			return templ_7745c5c3_CtxErr
 		}
-		_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ.EscapeString(templ_7745c5c3_Var27))
+		templ_7745c5c3_Buffer, templ_7745c5c3_IsBuffer := templruntime.GetBuffer(templ_7745c5c3_W)
+		if !templ_7745c5c3_IsBuffer {
+			defer func() {
+				templ_7745c5c3_BufErr := templruntime.ReleaseBuffer(templ_7745c5c3_Buffer)
+				if templ_7745c5c3_Err == nil {
+					templ_7745c5c3_Err = templ_7745c5c3_BufErr
+				}
+			}()
+		}
+		ctx = templ.InitializeContext(ctx)
+		templ_7745c5c3_Var30 := templ.GetChildren(ctx)
+		if templ_7745c5c3_Var30 == nil {
+			templ_7745c5c3_Var30 = templ.NopComponent
+		}
+		ctx = templ.ClearChildren(ctx)
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 57, "<form id=\"action-buttons\" class=\"actions\" method=\"post\" action=\"")
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}
-		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 51, "\" hx-post=\"")
+		var templ_7745c5c3_Var31 templ.SafeURL
+		templ_7745c5c3_Var31, templ_7745c5c3_Err = templ.JoinURLErrs(actionURL(videoID))
+		if templ_7745c5c3_Err != nil {
+			return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 194, Col: 29}
+		}
+		_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ.EscapeString(templ_7745c5c3_Var31))
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}
-		var templ_7745c5c3_Var28 string
-		templ_7745c5c3_Var28, templ_7745c5c3_Err = templ.ResolveAttributeValue(string(actionURL(videoID)))
-		if templ_7745c5c3_Err != nil {
-			return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 166, Col: 38}
-		}
-		_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ_7745c5c3_Var28)
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 58, "\" hx-post=\"")
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}
-		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 52, "\" hx-target=\"#action-buttons\" hx-swap=\"outerHTML\">")
+		var templ_7745c5c3_Var32 string
+		templ_7745c5c3_Var32, templ_7745c5c3_Err = templ.ResolveAttributeValue(string(actionURL(videoID)))
+		if templ_7745c5c3_Err != nil {
+			return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 195, Col: 38}
+		}
+		_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ_7745c5c3_Var32)
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 59, "\" hx-target=\"#action-buttons\" hx-swap=\"outerHTML\">")
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}
 		for _, v := range actionVerbs {
-			var templ_7745c5c3_Var29 = []any{"action", templ.KV("active", active[v])}
-			templ_7745c5c3_Err = templ.RenderCSSItems(ctx, templ_7745c5c3_Buffer, templ_7745c5c3_Var29...)
+			var templ_7745c5c3_Var33 = []any{"action", templ.KV("active", active[v])}
+			templ_7745c5c3_Err = templ.RenderCSSItems(ctx, templ_7745c5c3_Buffer, templ_7745c5c3_Var33...)
 			if templ_7745c5c3_Err != nil {
 				return templ_7745c5c3_Err
 			}
-			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 53, "<button type=\"submit\" name=\"action\" value=\"")
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 60, "<button type=\"submit\" name=\"action\" value=\"")
 			if templ_7745c5c3_Err != nil {
 				return templ_7745c5c3_Err
 			}
-			var templ_7745c5c3_Var30 string
-			templ_7745c5c3_Var30, templ_7745c5c3_Err = templ.ResolveAttributeValue(v)
+			var templ_7745c5c3_Var34 string
+			templ_7745c5c3_Var34, templ_7745c5c3_Err = templ.ResolveAttributeValue(v)
 			if templ_7745c5c3_Err != nil {
-				return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 174, Col: 13}
+				return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 203, Col: 13}
 			}
-			_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ_7745c5c3_Var30)
+			_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ_7745c5c3_Var34)
 			if templ_7745c5c3_Err != nil {
 				return templ_7745c5c3_Err
 			}
-			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 54, "\" class=\"")
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 61, "\" class=\"")
 			if templ_7745c5c3_Err != nil {
 				return templ_7745c5c3_Err
 			}
-			var templ_7745c5c3_Var31 string
-			templ_7745c5c3_Var31, templ_7745c5c3_Err = templ.ResolveAttributeValue(templ.CSSClasses(templ_7745c5c3_Var29).String())
+			var templ_7745c5c3_Var35 string
+			templ_7745c5c3_Var35, templ_7745c5c3_Err = templ.ResolveAttributeValue(templ.CSSClasses(templ_7745c5c3_Var33).String())
 			if templ_7745c5c3_Err != nil {
 				return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 1, Col: 0}
 			}
-			_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ_7745c5c3_Var31)
+			_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ_7745c5c3_Var35)
 			if templ_7745c5c3_Err != nil {
 				return templ_7745c5c3_Err
 			}
-			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 55, "\" aria-pressed=\"")
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 62, "\" aria-pressed=\"")
 			if templ_7745c5c3_Err != nil {
 				return templ_7745c5c3_Err
 			}
-			var templ_7745c5c3_Var32 string
-			templ_7745c5c3_Var32, templ_7745c5c3_Err = templ.ResolveAttributeValue(ariaPressed(active[v]))
+			var templ_7745c5c3_Var36 string
+			templ_7745c5c3_Var36, templ_7745c5c3_Err = templ.ResolveAttributeValue(ariaPressed(active[v]))
 			if templ_7745c5c3_Err != nil {
-				return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 176, Col: 41}
+				return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 205, Col: 41}
 			}
-			_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ_7745c5c3_Var32)
+			_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ_7745c5c3_Var36)
 			if templ_7745c5c3_Err != nil {
 				return templ_7745c5c3_Err
 			}
-			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 56, "\">")
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 63, "\">")
 			if templ_7745c5c3_Err != nil {
 				return templ_7745c5c3_Err
 			}
 			if active[v] {
-				var templ_7745c5c3_Var33 string
-				templ_7745c5c3_Var33, templ_7745c5c3_Err = templ.JoinStringErrs("✓ " + actionLabel(v))
+				var templ_7745c5c3_Var37 string
+				templ_7745c5c3_Var37, templ_7745c5c3_Err = templ.JoinStringErrs("✓ " + actionLabel(v))
 				if templ_7745c5c3_Err != nil {
-					return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 179, Col: 30}
+					return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 208, Col: 30}
 				}
-				_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ.EscapeString(templ_7745c5c3_Var33))
+				_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ.EscapeString(templ_7745c5c3_Var37))
 				if templ_7745c5c3_Err != nil {
 					return templ_7745c5c3_Err
 				}
 			} else {
-				var templ_7745c5c3_Var34 string
-				templ_7745c5c3_Var34, templ_7745c5c3_Err = templ.JoinStringErrs(actionLabel(v))
+				var templ_7745c5c3_Var38 string
+				templ_7745c5c3_Var38, templ_7745c5c3_Err = templ.JoinStringErrs(actionLabel(v))
 				if templ_7745c5c3_Err != nil {
-					return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 181, Col: 21}
+					return templ.Error{Err: templ_7745c5c3_Err, FileName: `internal/web/views.templ`, Line: 210, Col: 21}
 				}
-				_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ.EscapeString(templ_7745c5c3_Var34))
+				_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ.EscapeString(templ_7745c5c3_Var38))
 				if templ_7745c5c3_Err != nil {
 					return templ_7745c5c3_Err
 				}
 			}
-			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 57, "</button>")
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 64, "</button>")
 			if templ_7745c5c3_Err != nil {
 				return templ_7745c5c3_Err
 			}
 		}
-		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 58, "</form>")
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 65, "</form>")
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}