# Watch Multi-Profile Build Mechanism

**Status:** Draft
**Date:** 2026-05-20
**Related issues:** #1 (BLOCKER, prerequisite), #3 (this spec), #4 (follow-up hardening), #5 (long-term replacement)

## Context

The Wear OS app today bakes a single `SERVER_URL` and `API_KEY` into the APK at
build time via `BuildConfig` fields (see `clients/wearos/app/build.gradle.kts`).
The values come from one of three sources in order:

1. Gradle CLI property (`-Pdoctate.serverUrl=…`, `-Pdoctate.apiKey=…`)
2. `clients/wearos/local.properties` (gitignored, sticky default)
3. Hardcoded fallback (`http://10.0.2.2:3000`, `MISSING_API_KEY`)

`clients/wearos/run.sh` injects the Gradle properties for the `watch` target
based on the `DOCTATE_DEV_SERVER` and `DOCTATE_API_KEY` environment variables.

This mechanism handles a single developer talking to a single backend. It does
not cover the three scenarios that the project now needs:

1. **Brummel-Watch ↔ dev server** (Laptop, `http://192.168.178.27:3000`) —
   for server and watch co-development.
2. **Brummel-Watch ↔ minerva** (`http://minerva.lan:3000`) — for deployment
   smoke-testing on the alpha host.
3. **Krey-Watch ↔ minerva** — for Dr. Krey's clinical alpha use; this is
   **production data** (real patient dictations).

Switching today means manually editing `local.properties` or juggling env
vars, with no safeguard against the worst-case mistake: installing the wrong
profile on the wrong watch. Krey's production data is the failure mode that
forces an explicit defensive design.

## Goals

- **Three named profiles** addressable by short, explicit names:
  `brummel-dev`, `brummel-minerva`, `krey-minerva`.
- **One-command switch**: `./run.sh watch <profile> install` builds and installs
  with the chosen profile in one step.
- **Hard refusal** when a profile targets a watch that is not in its allow-list
  — this is the load-bearing safeguard against cross-contamination.
- **Zero external runtime dependencies** for `run.sh`: bash + adb + gradle only.
  No Python, no `jq`, no `yq`.
- **Single source of truth** per profile: server URL, API key, allowed ADB
  serials live in one place each, gitignored.

## Non-Goals

- **No self-service install for Krey** — APK deployment is physical via ADB on
  Brummel's laptop. A pairing flow (Issue #5) is explicitly out of scope.
- **No release-signed APKs / no signed artifact handoff** — debug builds over
  ADB are sufficient for the current testing tier.
- **No coexistence on a single watch** — one APK per watch, profile switches
  reinstall. Coexistence via `applicationIdSuffix` was considered and rejected
  as unneeded.
- **No server-side validation that an api_key is not a bcrypt hash** — that is
  Issue #4 and lives in a separate follow-up.
- **No runtime profile selection on the watch** — build-time only; runtime
  selection would require a full pairing/settings UI (Issue #5).

## Design

### Profile data structure

One file per profile under `clients/wearos/profiles.d/<name>.sh`, sourced as
bash. All profile files are gitignored; a sibling `*.sh.example` is checked in
as a format template.

```bash
# clients/wearos/profiles.d/brummel-dev.sh  (gitignored)
SERVER_URL="http://192.168.178.27:3000"
API_KEY="<plaintext key from server's users.toml under slug 'brummel'>"
ALLOWED_SERIALS=(
    "adb-XXXXXXXX-yyyy._adb-tls-connect._tcp"
)
```

```bash
# clients/wearos/profiles.d/brummel-minerva.sh  (gitignored)
SERVER_URL="http://minerva.lan:3000"
API_KEY="<plaintext key from minerva's users.toml under slug 'brummel'>"
ALLOWED_SERIALS=(
    "adb-XXXXXXXX-yyyy._adb-tls-connect._tcp"
)
```

```bash
# clients/wearos/profiles.d/krey-minerva.sh  (gitignored)
SERVER_URL="http://minerva.lan:3000"
API_KEY="<plaintext key from minerva's users.toml under slug 'krey'>"
ALLOWED_SERIALS=(
    "adb-ZZZZZZZZ-wwww._adb-tls-connect._tcp"
)
```

`.gitignore` rule:

```
clients/wearos/profiles.d/*.sh
!clients/wearos/profiles.d/*.sh.example
```

A bash-source format was chosen over TOML/JSON to keep `run.sh` zero-dependency.
The risk of code execution via a profile file is acceptable because the file is
single-user, gitignored, and authored by the developer themselves. A move to
TOML would become attractive if profiles ever come from elsewhere or the user
base grows.

`ALLOWED_SERIALS` is an array, not a scalar, so a future watch swap can list
both old and new serials during a transition without a schema change.

### CLI form

```
./run.sh watch <profile> <subcmd> [args]
./run.sh emulator <subcmd> [args]            # unchanged, no profile
```

The profile name is a required second positional argument for the `watch`
target. The `emulator` target keeps its existing hardcoded loopback config.

Existing subcommands (`install`, `build`, `start`, `stop`, `logcat`, `shot`,
`test`) all accept the profile in the new position.

### run.sh internals

New helper functions:

```bash
load_profile() {
    local name="$1"
    local file="$SCRIPT_DIR/profiles.d/$name.sh"
    if [[ ! -f "$file" ]]; then
        local available
        available="$(cd "$SCRIPT_DIR/profiles.d" 2>/dev/null && \
                     ls *.sh 2>/dev/null | sed 's/\.sh$//' | tr '\n' ' ')"
        [[ -z "$available" ]] && available="<none — create one in profiles.d/>"
        die "Unknown profile '$name'. Available: ${available}"
    fi
    # Reset to detect missing fields after sourcing.
    SERVER_URL=""; API_KEY=""; ALLOWED_SERIALS=()
    # shellcheck disable=SC1090
    source "$file"
    [[ -n "$SERVER_URL" ]] || die "Profile '$name': SERVER_URL missing"
    [[ -n "$API_KEY"    ]] || die "Profile '$name': API_KEY missing"
    [[ "${#ALLOWED_SERIALS[@]}" -gt 0 ]] || die "Profile '$name': ALLOWED_SERIALS empty"
}

verify_serial_allowed() {
    local serial="$1"
    local s
    for s in "${ALLOWED_SERIALS[@]}"; do
        [[ "$s" == "$serial" ]] && return 0
    done
    die "Watch serial '$serial' is NOT in ALLOWED_SERIALS for profile '$DOCTATE_PROFILE'.
Allowed: ${ALLOWED_SERIALS[*]}
This refusal protects against installing the wrong key on the wrong watch
(e.g. Brummel-key on Krey's watch → patient data goes to dev server)."
}
```

Updated `apply_target` for the `watch` target:

```bash
case "$DOCTATE_TARGET" in
    watch)
        [[ -n "$DOCTATE_PROFILE" ]] || die \
            "Watch target requires a profile. Usage: ./run.sh watch <profile> <subcmd>"
        load_profile "$DOCTATE_PROFILE"
        if [[ -z "$ADB_SERIAL" ]]; then
            resolve_watch_serial
            ADB_SERIAL="$RESOLVED_SERIAL"
        fi
        verify_serial_allowed "$ADB_SERIAL"
        GRADLE_PROPS+=(
            "-Pdoctate.serverUrl=$SERVER_URL"
            "-Pdoctate.apiKey=$API_KEY"
            "-Pdoctate.profileName=$DOCTATE_PROFILE"
        )
        info "Target: watch (profile=$DOCTATE_PROFILE, serial=$ADB_SERIAL, server=$SERVER_URL)"
        ;;
    emulator)
        # existing logic, unchanged
        ;;
esac
```

The `verify_serial_allowed` check runs BEFORE Gradle is invoked, so a mismatch
fails fast without burning a minute-long build.

Argument-parsing changes: the second positional after `watch` becomes the
profile name; subcmd shifts to the third position. The `emulator` target keeps
the second-positional-is-subcmd shape.

Removed (breaking change inside `run.sh`, no callers outside):

- `DOCTATE_DEV_SERVER` env var and `DEFAULT_DEV_SERVER` constant
- `DOCTATE_API_KEY` env var
- `doctate.apiKey=…` line in `local.properties` (the file becomes empty or
  deleted; profile data is canonical)

Help-text block at the top of `run.sh` is rewritten to document the new form.

### BuildConfig and visual badge (nice-to-have)

`clients/wearos/app/build.gradle.kts` resolves two new build config fields:

```kotlin
val profileName = resolveProp("doctate.profileName", "unknown")
val isDevProfile = profileName.endsWith("-dev")

buildConfigField("String",  "PROFILE_NAME",   "\"$profileName\"")
buildConfigField("boolean", "IS_DEV_PROFILE", "$isDevProfile")

manifestPlaceholders["appLabel"] = if (isDevProfile) "Doctate (Dev)" else "Doctate"
```

`AndroidManifest.xml` uses the placeholder:

```xml
<application android:label="${appLabel}" ...>
```

A `DevBadge` composable in `presentation/components/DevBadge.kt` renders a small
red "DEV" tag, but only when `BuildConfig.IS_DEV_PROFILE` is true:

```kotlin
@Composable
fun DevBadge(modifier: Modifier = Modifier) {
    if (!BuildConfig.IS_DEV_PROFILE) return
    Text(
        text = "DEV",
        color = Color(0xFFFF5252),
        style = MaterialTheme.typography.labelSmall.copy(fontWeight = FontWeight.Bold),
        modifier = modifier
            .background(Color.Black.copy(alpha = 0.6f), RoundedCornerShape(4.dp))
            .padding(horizontal = 4.dp, vertical = 1.dp)
    )
}
```

Mounted in `CaseListScreen` (top-right) and `RecordingScreen` (top-right next to
the `mm:ss` counter). Production profiles render no badge — Krey's UI stays
clean.

This visual layer is classified as nice-to-have. The hard-lock in `run.sh`
prevents the worst-case misinstall regardless; the badge protects against the
softer case where Brummel forgets which profile is currently installed.

## Prerequisites

These are external to the Watch code but must be done before the watch profiles
work end-to-end.

### V1 — Resolve Issue #1 (BLOCKER)

Edit `/opt/stacks/doctate-server/config/users.toml` on minerva: replace bcrypt
hashes in `api_key` fields with fresh plaintext values (one per user, e.g.
`openssl rand -base64 24`). Reload the container.

The server's auth path (`server/src/auth.rs:52`) does a plaintext HashMap
lookup; bcrypt-shaped values in `api_key` never match the plaintext the watch
sends, producing silent 401s.

### V2 — Add Krey to minerva's users.toml

Create the `krey` user entry on minerva with:

- `slug = "krey"`
- `display_name = "Dr. Krey"` (or her preferred form)
- `api_key = "<fresh plaintext, openssl rand -base64 24>"`
- `web_password = "<bcrypt hash via the hash-password CLI>"`
- `role = "doctor"` (not admin — Krey should not see reset/purge controls)

### V3 — Collect ADB serials

For each watch in turn:

1. Pair via `./run.sh connect <host:port>` (Pixel Watch over ADB-WiFi).
2. List the attached devices via `./run.sh devices` and copy the watch's
   serial, which has the shape `adb-XXXXXXXX-yyyy._adb-tls-connect._tcp`.
3. Paste it into the corresponding profile file's `ALLOWED_SERIALS` array.

A serial can appear in more than one profile (e.g. Brummel's watch is allowed
under both `brummel-dev` and `brummel-minerva`). Krey's serial appears only
under `krey-minerva`.

## Roll-out

```mermaid
graph TD
    V1[V1: minerva users.toml plaintext keys<br/>= Issue #1 fix] --> V2
    V2[V2: add Krey user to minerva] --> S1
    V3[V3: collect ADB serials of both watches] --> S1

    S1[S1: profiles.d/ mechanism in run.sh] --> S2
    S2[S2: create three profile files<br/>brummel-dev, brummel-minerva, krey-minerva] --> S3
    S3[S3: BuildConfig PROFILE_NAME + IS_DEV_PROFILE<br/>+ manifest appLabel] --> S4
    S4[S4: visual DEV badge (optional)] --> S5
    S5[S5: smoke-test matrix]
```

V1, V2, V3 can run in parallel. S1–S5 are sequential. S4 may be deferred
without blocking the rest.

## Smoke-test matrix

After implementation, run each row once and confirm the expected outcome:

| Command | Watch attached | Expected |
|---|---|---|
| `./run.sh watch brummel-dev install` | Brummel | Build + install, app talks to laptop IP, `/api/oneliners` → 200 |
| `./run.sh watch brummel-dev install` | Krey | Hard-refuse with allowed_serials mismatch message |
| `./run.sh watch brummel-minerva install` | Brummel | App talks to `minerva.lan:3000`, 200 |
| `./run.sh watch krey-minerva install` | Krey | App talks to `minerva.lan:3000` under slug `krey`, 200 |
| `./run.sh watch krey-minerva install` | Brummel | Hard-refuse |
| `./run.sh watch unknown-profile install` | any | Error listing available profiles |
| `./run.sh watch brummel-dev` | any | Error: subcommand missing |
| `./run.sh emulator install` | (emulator) | Unchanged behavior, no profile required |

Visual checks for the optional badge layer:

- Brummel-Watch with `brummel-dev` installed: launcher shows "Doctate (Dev)",
  CaseListScreen and RecordingScreen show red "DEV" badge.
- Brummel-Watch with `brummel-minerva` installed: launcher shows "Doctate",
  no badge anywhere.
- Krey-Watch with `krey-minerva` installed: launcher shows "Doctate",
  no badge anywhere.

## Out of scope (deliberate)

- **Issue #4 (Server sanity-check for bcrypt-shaped api_key)** — natural
  follow-up after V1, before S1. Tracked separately. Same risk surface; a
  single PR would mix concerns.
- **Issue #5 (Watch pairing flow)** — the principled long-term replacement
  for build-time profile baking. Out of reach for this spec.
- **APK distribution to Krey via filesharing / release signing** — not needed
  while Brummel installs physically via ADB.
- **Theme tinting / boot splash per profile** — judged unnecessary given the
  launcher label and optional badge already cover the visibility need.
