tapir/docs/ui-spec.md

# Tapir — Web UI Spec (Stage 0)

Implementation-level spec for the first web surface. Scope is **Stage 0: a reading surface
for the maintainer's own summaries, instrumented to capture the Stage-0 headline test**
("reads summaries weekly and acts on ≥1"). Deployed at `tapir.d-ma.be` via the homelab
GitOps flow. See `VISION.md` (Stage 0 gate), `DECISIONS.md` (ADR-011), `docs/data-model.md`.

## 1. Goal & success criteria

- The maintainer can, from a browser, **read** Tapir's summaries (list + full view) and
  **act** on them (watch / skip / save), with the action recorded.
- Auth is real (Dex OIDC login), but authorization is **single-user**: an allowlist of one
  subject. No user management, no per-tenant isolation (those are Stage 1+).
- Runs as a deployed k3s service behind `tapir.d-ma.be`, secrets via ESO, DB in-cluster —
  i.e. the same binary, "homelab mode" wiring (ADR-003).
- **Done when:** logging in at `tapir.d-ma.be` shows the maintainer's real summaries, opening
  one shows highlights/takeaways, and clicking watch/skip/save persists and is queryable.

## 2. Non-goals (Stage 1+ — do NOT build)

- Multiple users, sign-up, user CRUD, per-tenant data isolation/RLS.
- Editing summaries, subscription management UI, triggering runs from the browser (the run
  loop stays a `tapir run` job for now — revisit later).
- Any billing / public marketing surface. Mobile-native. Real-time push.

## 3. Architecture

- **New transport, not new core.** Add `tapir serve` (subcommand of `cmd/tapir`). It is a
  read/write surface over the existing `store`; the engine, ports, and adapters are
  untouched (ADR-003 — standalone vs homelab is wiring).
- **Stack:** Go stdlib `net/http` + **Templ** (typed templates) + **HTMX** (progressive
  interactions, no SPA). House default; a summary reader is read-heavy and low-interactivity.
- **Layers:** `internal/web/` (handlers, session, middleware, Templ components) depends on
  the `store` read/write methods and a thin `auth/oidc` session package. No business logic in
  handlers beyond presentation + action recording.

## 4. Pages & interactions

| Route | Method | What |
|-------|--------|------|
| `/healthz` | GET | liveness/readiness (no auth) |
| `/auth/login` | GET | redirect to Dex authorize |
| `/auth/callback` | GET | OIDC code exchange → session cookie → redirect to `/` |
| `/auth/logout` | POST | clear session |
| `/` | GET | summary list (auth) — newest first; columns: title · channel · published · AI provider · fallback badge · current action state. Filters: channel, date range (query params, HTMX-swapped) |
| `/v/{videoId}` | GET | full summary: text, highlights (list), takeaways (list), metadata, action buttons |
| `/v/{videoId}/action` | POST | record/clear an action `{watched\|skipped\|saved}` (HTMX, returns the updated button group fragment — no full reload) |

- **HTMX patterns:** filters and action buttons POST/GET and swap a fragment (`hx-target`,
  `hx-swap`). Full-page fallback works without JS (forms degrade).
- **Action semantics:** the three actions are independent toggles per (user, video) —
  "saved" can coexist with "watched"; "skipped" is mutually exclusive with "watched"
  (clicking one clears the other). Re-clicking an active action clears it.

## 5. Data model addition

New table `summary_actions` (migration, golang-migrate, per estate convention):

```
summary_actions
  id          uuid pk
  user_id     uuid   not null      -- isolation column (dormant authz at Stage 0)
  video_id    text   not null
  action      text   not null      -- 'watched' | 'skipped' | 'saved'
  acted_at    timestamptz not null
  unique (user_id, video_id, action)
```

- Store methods (new file `internal/adapters/store/actions.go`, do not edit existing store
  files): `SetAction(ctx, userID, videoID, action) error`, `ClearAction(...)`,
  `ActionsFor(ctx, userID, videoIDs []string) (map[videoID][]action, error)` for the list,
  and join into the existing `SummaryRow` reads so list/detail show current state.
- This column is what makes the Stage-0 metric ("did I act on a summary?") queryable.

## 6. Auth (Dex OIDC, single-user authz)

- **Flow:** standard Authorization Code. Use `coreos/go-oidc` + `golang.org/x/oauth2`
  (justify the deps in the commit; both are the homelab-standard OIDC libs and small).
- Discover issuer `https://auth.d-ma.be` (`TAPIR_OIDC_ISSUER`); scopes `openid profile email`.
- On callback: verify ID token, extract `sub` (and email). **ADR-012 superseded the
  ADR-011 single-subject allowlist:** any Dex-authenticated subject may sign in; a subject
  with no tapir user is routed to explicit registration (see `internal/web` registration gate).
- **Session:** signed, httpOnly, Secure cookie (HS256 with `TAPIR_SESSION_SECRET`); short TTL
  + sliding refresh. Server-side session store can be in-memory at Stage 0 (single replica).
- **Middleware** guards every route except `/healthz` and `/auth/*`.
- Note: this is `mcp-chassis`'s cousin but NOT the same code — mcp-chassis validates inbound
  *Bearer JWTs* for MCP APIs; this is a *browser session* login. Don't force-fit it.

## 7. Config additions (typed, env, via ESO in-cluster)

`TAPIR_HTTP_ADDR` (`:8080`), `TAPIR_PUBLIC_URL` (`https://tapir.d-ma.be`),
`TAPIR_OIDC_ISSUER` (`https://auth.d-ma.be`), `TAPIR_DEX_CLIENT_ID`, `TAPIR_DEX_CLIENT_SECRET`,
`TAPIR_OIDC_REDIRECT_URL` (`https://tapir.d-ma.be/auth/callback`), `TAPIR_SESSION_SECRET`.
Reuses existing `TAPIR_DB_DSN`, `TAPIR_USER_ID` (the StubAuth dev subject only). No secrets
committed. (`TAPIR_ALLOWED_SUBJECT` was removed by ADR-012.)

## 8. Deployment — k3s + Flux GitOps

- **Image:** `Dockerfile` (multi-stage, distroless/static, non-root). Built by **gitea CI**
  (act_runner + buildah) on push to `main`, pushed to the homelab registry
  (`k8s-registry-pull` secret already exists), GitHub mirror per the `gitea-ci` skill.
- **Manifests live in `mathias/infra` under `k3s/apps/tapir/`** (NOT this repo — app vs
  deployment separation, homelab-integration.md). Flux watches `infra` `main` and reconciles:
  - `Deployment` (1 replica Stage 0), `Service`, `Ingress` for **`tapir.d-ma.be`** (TLS via
    the homelab cert flow / edge), `ExternalSecret` (ESO) materialising `TAPIR_*` secrets from
    the `HomeLab` 1Password vault into a k8s `Secret` mounted as env.
- **DB in-cluster:** the deployed service connects to `postgres18` via its ClusterIP DSN
  (no port-forward); migrations apply on first connect (`store.Migrate`). The `tapir` role/db
  already exist; the in-cluster DSN goes in `op://HomeLab/TAPIR_DB_DSN_INCLUSTER` (or reuse
  with host swapped) and is surfaced via ESO.
- **YouTube refresh token in-cluster:** `tapir auth` is interactive (host-only). Run it once
  on the host, store the resulting refresh token in 1Password, and have the deployed pod's
  `SecretStore` resolve it from the ESO-synced secret (an ESO/k8s-secret-backed SecretStore
  impl, swappable behind the port). The web UI itself does not need the YouTube token; only
  the `run` job does — decide whether `run` is a CronJob in the same deploy or stays host-side
  for now (recommend: CronJob in `k3s/apps/tapir/` once the web UI is up).

## 9. Prerequisites (maintainer setup, before/with the build)

1. **Register a Dex static client** `tapir-web` in the Dex config (in `infra`) with redirect
   `https://tapir.d-ma.be/auth/callback`; client id/secret → 1P `TAPIR_DEX_CLIENT_ID` /
   `TAPIR_DEX_CLIENT_SECRET`. (No allowlist subject to capture — ADR-012 dropped it.)
2. **DNS/edge** for `tapir.d-ma.be` → the k3s ingress (piguard NPM perimeter / existing
   `*.d-ma.be` pattern) + TLS cert.
3. Confirm the **registry** host/path the gitea CI pushes to and the Flux path
   `infra/k3s/apps/tapir/`.

## 10. Records / ADR

`ADR-011` records: the web read-surface at Stage 0, Dex *authentication* now with *trivial
single-user authz* (deviating from the data-model's "auth dormant at Stage 0" note, with
rationale), the `summary_actions` model, and public `tapir.d-ma.be` ingress + GitOps deploy.

## 11. Build decomposition (gated swarm)

Gate (lane A) commits first; B/C/D follow.

- **Lane A — store actions + migration** (the gate): `summary_actions` migration,
  `SetAction`/`ClearAction`/`ActionsFor`, join into `SummaryRow`. embedded-postgres tests.
- **Lane B — Dex OIDC session + middleware**: login/callback/logout, session cookie,
  allowlist, route guard. Tests with a fake issuer (httptest), no live Dex.
- **Lane C — Templ+HTMX pages**: list (+filters), detail (+action button group fragment),
  layout/styles, `tapir serve` wiring. Handler tests.
- **Lane D — deploy**: `Dockerfile`, gitea CI image build + mirror, and the `infra`
  `k3s/apps/tapir/` manifests (Deployment/Service/Ingress/ExternalSecret) + Flux. (Touches the
  `infra` repo, not just this one.)

`task check` green per lane; B/C/D rebase on A. Deploy (D) lands last, after the binary serves
locally.