feat(api): add passkey enrollment persistence layer

	// can answer 429 (back off / request a new code) rather than inviting another

	// guess against a code that will never accept one.

	ErrOTPLocked = errors.New("email code locked: too many attempts")

	// ErrPasskeyChallengeInvalid means a passkey enrollment ceremony cannot be

	// finished: there is no live (unconsumed, unexpired) challenge for the caller and

	// purpose (Phase 6 WebAuthn bind). Like ErrOTPInvalid it is a client error — the

	// finish endpoint exists; the ceremony state is gone (never begun, already

	// consumed, or expired) — so handlers map it to 400, not 404.

	ErrPasskeyChallengeInvalid = errors.New("passkey challenge invalid or expired")

)

// apiError is a handler-level error carrying an HTTP status and a stable,

		key, string(value))

	return err

}

// ---- player passkey enrollment (spec §14 WebAuthn / Phase 6 bind, migration 0007) ----

// CreatePasskeyChallenge supersedes any prior live challenge for (user, purpose) and

// inserts the fresh one, in one transaction (mirrors CreateEmailOTP). The supersede

// DELETE means a re-begin invalidates the earlier ceremony, so only the most recent

// challenge can ever finish — at most one outstanding challenge per (user, purpose).

// The opaque SessionData is held server-side so the client cannot forge the challenge

// it must answer at finish.

func (p *PGRepo) CreatePasskeyChallenge(ctx context.Context, id, userID, purpose string, sessionData []byte, expiresAt time.Time) error {

	tx, err := p.db.BeginTx(ctx, nil)

	if err != nil {

		return err

	}

	defer tx.Rollback() //nolint:errcheck // no-op after commit

	if _, err := tx.ExecContext(ctx,

		`DELETE FROM webauthn_challenges WHERE user_id = $1 AND purpose = $2 AND consumed_at IS NULL`,

		userID, purpose); err != nil {

		return fmt.Errorf("supersede prior passkey challenge: %w", err)

	}

	if _, err := tx.ExecContext(ctx,

		`INSERT INTO webauthn_challenges (id, user_id, purpose, session_data, expires_at)

		 VALUES ($1, $2, $3, $4, $5)`,

		id, userID, purpose, sessionData, expiresAt); err != nil {

		return fmt.Errorf("insert passkey challenge: %w", err)

	}

	return tx.Commit()

}

// ConsumePasskeyChallengeByUser redeems the newest live (unconsumed, unexpired at now)

// challenge for (user, purpose) in one transaction (mirrors VerifyEmailOTP). The row is

// taken FOR UPDATE so a concurrent finish cannot double-spend it; expiry is checked

// before consuming so a stale challenge is never accepted. On success consumed_at is

// stamped (single-use) and the stashed SessionData is returned. No live row →

// ErrPasskeyChallengeInvalid.

func (p *PGRepo) ConsumePasskeyChallengeByUser(ctx context.Context, userID, purpose string, now time.Time) ([]byte, error) {

	tx, err := p.db.BeginTx(ctx, nil)

	if err != nil {

		return nil, err

	}

	defer tx.Rollback() //nolint:errcheck // no-op after commit

	var (

		id          string

		sessionData []byte

		expiresAt   time.Time

	)

	switch err := tx.QueryRowContext(ctx,

		`SELECT id, session_data, expires_at FROM webauthn_challenges

		 WHERE user_id = $1 AND purpose = $2 AND consumed_at IS NULL

		 ORDER BY created_at DESC LIMIT 1 FOR UPDATE`,

		userID, purpose).Scan(&id, &sessionData, &expiresAt); {

	case errors.Is(err, sql.ErrNoRows):

		return nil, ErrPasskeyChallengeInvalid

	case err != nil:

		return nil, err

	}

	if !expiresAt.After(now) {

		return nil, ErrPasskeyChallengeInvalid

	}

	if _, err := tx.ExecContext(ctx,

		`UPDATE webauthn_challenges SET consumed_at = $2 WHERE id = $1`, id, now); err != nil {

		return nil, fmt.Errorf("consume passkey challenge: %w", err)

	}

	if err := tx.Commit(); err != nil {

		return nil, err

	}

	return sessionData, nil

}

// CreatePasskeyCredential stores a freshly verified passkey (enrollment). Only public

// attestation material is written; a credential_id already bound to ANY account is left

// untouched (ON CONFLICT DO NOTHING) and reported as ErrConflict via a zero RowsAffected,

// so an authenticator is never silently rebound. Empty aaguid/name land as SQL NULL.

func (p *PGRepo) CreatePasskeyCredential(ctx context.Context, c PasskeyCredential) error {

	res, err := p.db.ExecContext(ctx,

		`INSERT INTO webauthn_credentials (id, user_id, credential_id, public_key, sign_count, aaguid, name, created_at)

		 VALUES ($1, $2, $3, $4, $5, NULLIF($6, ''), NULLIF($7, ''), $8)

		 ON CONFLICT (credential_id) DO NOTHING`,

		c.ID, c.UserID, c.CredentialID, c.PublicKey, int64(c.SignCount), c.AAGUID, c.Name, c.CreatedAt)

	if err != nil {

		return err

	}

	n, err := res.RowsAffected()

	if err != nil {

		return err

	}

	if n == 0 {

		return ErrConflict

	}

	return nil

}

// PasskeyCredentialsForUser lists the passkeys a user has bound, newest first, for the

// credential-management view. Nullable aaguid/name collapse to "" via COALESCE; the

// nullable last_used_at maps to a *time.Time (nil until an assertion is verified).

func (p *PGRepo) PasskeyCredentialsForUser(ctx context.Context, userID string) ([]PasskeyCredential, error) {

	const q = `SELECT id, user_id, credential_id, public_key, sign_count,

		COALESCE(aaguid, ''), COALESCE(name, ''), created_at, last_used_at

		FROM webauthn_credentials WHERE user_id = $1 ORDER BY created_at DESC`

	rows, err := p.db.QueryContext(ctx, q, userID)

	if err != nil {

		return nil, err

	}

	defer rows.Close()

	var out []PasskeyCredential

	for rows.Next() {

		var (

			c         PasskeyCredential

			signCount int64

			lastUsed  sql.NullTime

		)

		if err := rows.Scan(&c.ID, &c.UserID, &c.CredentialID, &c.PublicKey, &signCount,

			&c.AAGUID, &c.Name, &c.CreatedAt, &lastUsed); err != nil {

			return nil, err

		}

		c.SignCount = uint32(signCount)

		if lastUsed.Valid {

			t := lastUsed.Time

			c.LastUsedAt = &t

		}

		out = append(out, c)

	}

	return out, rows.Err()

}

// DeletePasskeyCredential removes the passkey row id, scoped to userID so a caller can

// only unbind their OWN credential. No matching (user, id) row → ErrNotFound via a zero

// RowsAffected, so a stale or cross-user id cannot silently no-op as success.

func (p *PGRepo) DeletePasskeyCredential(ctx context.Context, userID, id string) error {

	res, err := p.db.ExecContext(ctx,

		`DELETE FROM webauthn_credentials WHERE id = $1 AND user_id = $2`, id, userID)

	if err != nil {

		return err

	}

	n, err := res.RowsAffected()

	if err != nil {

		return err

	}

	if n == 0 {

		return ErrNotFound

	}

	return nil

}

	EmailVerified bool

}

// PasskeyCredential is one bound passkey (Phase 6 WebAuthn enrollment). It carries

// only public, non-secret attestation material: a WebAuthn public key is meant to

// be public (unlike a session token), so it is safe at rest. CredentialID is the

// authenticator's globally-unique handle (base64url) and PublicKey the COSE key

// (base64); SignCount is the uint32 signature counter captured at registration.

// LastUsedAt is nil until an assertion is verified — the login/step-up path that

// would stamp it is out of scope for this enrollment-only slice (deferred), so it

// stays nil through the flow this type backs.

type PasskeyCredential struct {

	ID           string

	UserID       string

	CredentialID string

	PublicKey    string

	SignCount    uint32

	AAGUID       string

	Name         string

	CreatedAt    time.Time

	LastUsedAt   *time.Time

}

// SessionedUser is the projection resolved from a live session cookie: the

// identity SessionAuth needs to build a Principal. It omits the password hash —

// the session has already authenticated the caller — but carries the pending

	// proven email is returned. now is the API clock so expiry is testable.

	VerifyEmailOTP(ctx context.Context, userID, purpose, codeHash string, now time.Time) (email string, err error)

	// ---- player passkey enrollment (spec §14 WebAuthn / Phase 6 bind) ----

	// CreatePasskeyChallenge persists the server-side state of a credential-creation

	// ceremony for (userID, purpose): the opaque go-webauthn SessionData blob and its

	// expiry. Only the server holds it, so the client cannot forge the challenge it

	// must answer at finish. It supersedes any prior live (unconsumed) challenge for

	// the same (userID, purpose) so a re-begin invalidates the earlier ceremony —

	// at most one outstanding challenge per (user, purpose). expiresAt is the API

	// clock + TTL so expiry is driven by one authoritative clock.

	CreatePasskeyChallenge(ctx context.Context, id, userID, purpose string, sessionData []byte, expiresAt time.Time) error

	// ConsumePasskeyChallengeByUser redeems the newest live (unconsumed, unexpired at

	// now) challenge for (userID, purpose), atomically: it stamps consumed_at and

	// returns the stashed SessionData so finish can validate the attestation against

	// it. No live challenge → ErrPasskeyChallengeInvalid. Single-use: a second finish

	// for the same ceremony finds nothing live and fails. now is the API clock so

	// expiry is testable. Bound to user_id — enrollment always has a principal, so

	// there is no usernameless consume-by-hash variant (login is a deferred slice).

	ConsumePasskeyChallengeByUser(ctx context.Context, userID, purpose string, now time.Time) (sessionData []byte, err error)

	// CreatePasskeyCredential stores a freshly verified passkey for a user (Phase 6

	// enrollment). It writes only public attestation material (credential_id,

	// public_key, sign_count, aaguid) plus the caller's nickname. A credential_id

	// already bound to ANY account → ErrConflict (the UNIQUE guard); the handler maps

	// that to 409 rather than silently rebinding an authenticator.

	CreatePasskeyCredential(ctx context.Context, c PasskeyCredential) error

	// PasskeyCredentialsForUser lists the passkeys a user has bound, newest first, for

	// the credential-management view. It returns only display fields (never a secret —

	// a passkey carries none); LastUsedAt is nil where no assertion has been verified.

	PasskeyCredentialsForUser(ctx context.Context, userID string) ([]PasskeyCredential, error)

	// DeletePasskeyCredential removes the passkey row id, scoped to userID so a caller

	// can only unbind their OWN credential. No matching (user, id) row → ErrNotFound,

	// so a stale or cross-user id cannot silently no-op as success.

	DeletePasskeyCredential(ctx context.Context, userID, id string) error

	// ---- player game-login: username-collision reclaim (spec §B3) ----

	// ReclaimUsername records a Mojang-priority username reclaim, atomically (spec

-- Phase 6 passkey/WebAuthn bind (spec §14 WebAuthn, §B2 onboarding "link + email-OTP

-- + passkey"). This is the ENROLLMENT data layer only: an already-authenticated

-- principal binds a passkey to their account (the credential-creation ceremony),

-- and manages the credentials they have bound. Email-OTP remains the fallback

-- factor (migration 0004), so a player with no passkey is never locked out.

--

-- Scope boundary (deliberate): this slice covers ENROLLMENT only. Assertion

-- verification for LOGIN — proving a passkey to mint/elevate a session from an

-- unauthenticated state — is out of scope here and deferred. The spec keeps the two

-- passkey surfaces distinct (§14: admin.* rides "Tunnel+Access，WebAuthn/posture",

-- panel.* is "app 登录"; §B2 lists passkey among the player onboarding factors), so

-- where the panel.* passkey relying-party boundary ultimately lands (felis-api vs.

-- the Access edge) is a later decision, not settled by this migration. Accordingly

-- this migration models only the authenticated enrollment ceremony: every challenge

-- is bound to a known user_id, and there is no usernameless (pre-session) login

-- lookup column. Adding a login path later would also need the felis_session

-- honoring model in session.go extended.

-- webauthn_credentials stores one bound passkey per row. The public key and the

-- signature counter are attestation outputs captured at registration; only public,

-- non-secret material is held (a WebAuthn public key is meant to be public, unlike

-- the RCON password or a session token). credential_id is the authenticator's

-- globally-unique handle, base64url-encoded; UNIQUE guards the (astronomically

-- unlikely) cross-account collision and is the key a future login path would match.

CREATE TABLE webauthn_credentials (

  id            text PRIMARY KEY,                      -- opaque row id (crypto-random hex)

  user_id       text NOT NULL REFERENCES users(id),

  credential_id text NOT NULL UNIQUE,                  -- base64url(raw credential id)

  public_key    text NOT NULL,                         -- base64(COSE public key bytes)

  sign_count    bigint NOT NULL DEFAULT 0,             -- uint32 widened (overflows int4)

  aaguid        text,                                  -- authenticator model id, for display only

  name          text,                                  -- caller-supplied nickname ("My phone")

  created_at    timestamptz NOT NULL DEFAULT now(),

  last_used_at  timestamptz                            -- NULL until an assertion is verified (deferred login path)

);

-- The credential-management views list a user's bound passkeys, so index that lookup.

CREATE INDEX webauthn_credentials_user_id_idx ON webauthn_credentials (user_id);

-- webauthn_challenges holds the server-side ceremony state between begin and finish.

-- The full go-webauthn SessionData blob (challenge, allowed credentials, expiry) is

-- stashed here and reloaded at finish, so the client never echoes — and so cannot

-- forge — the challenge it must answer (the same principle as email_otps.code_hash).

-- Every row is bound to a known user_id (NOT NULL): enrollment always rides on an

-- authenticated principal, so there is no usernameless consume-by-hash path. consumed_at

-- enforces single-use; a fresh begin supersedes the prior live row for (user, purpose).

CREATE TABLE webauthn_challenges (

  id           text PRIMARY KEY,                       -- opaque row id (crypto-random hex)

  user_id      text NOT NULL REFERENCES users(id),

  purpose      text NOT NULL,                          -- 'passkey_register'

  session_data bytea NOT NULL,                         -- opaque go-webauthn SessionData

  expires_at   timestamptz NOT NULL,                   -- short TTL set by the API clock

  consumed_at  timestamptz,                            -- non-NULL once redeemed (single-use)

  created_at   timestamptz NOT NULL DEFAULT now()

);

-- The finish path consumes the newest live row for a (user, purpose), so index it.

CREATE INDEX webauthn_challenges_user_purpose_idx ON webauthn_challenges (user_id, purpose);