Refactor: split monolith into cmd/palette + internal/{store,api,web,lang} (#35)

internal/store/burn.go

@@ -0,0 +1,71 @@
+package store
+
+import (
+	"crypto/subtle"
+	"database/sql"
+	"encoding/base64"
+	"time"
+)
+
+// genDeletionToken returns a 32-char url-safe random token
+func genDeletionToken() string {
+	b := make([]byte, 24)
+	cryptoRead(b)
+	return base64.RawURLEncoding.EncodeToString(b)
+}
+
+// TimeNow is overridable in tests to inject the clock.
+var TimeNow = time.Now
+
+// registerRead applies the burn-after-read budget for one view (#49).
+// For pastes with reads_limit set: the viewer's paste_views row is checked;
+// a view within the burn viewer window of the viewer's last view is deduped
+// (count=false). Otherwise reads_used is incremented, and the paste is
+// soft-deleted (burned) once reads_used reaches reads_limit. Viewers without
+// a cookie (plain API clients) count as their own viewer id "".
+// For legacy plain burn_after_read pastes (no reads_limit), any read burns.
+// Returns the number of reads remaining (0 when burned), or nil when no
+// budget is set. view_count is tracked separately and unaffected.
+func (s *Store) RegisterRead(row *PasteRow, viewerID string, burnWindowMinutes int) (remaining *int, count bool) {
+	if !row.ReadsLimit.Valid {
+		if row.BurnAfterRead {
+			s.SoftDelete(row.ID)
+			r := 0
+			return &r, true
+		}
+		return nil, false
+	}
+	now := TimeNow().Unix()
+	var last sql.NullInt64
+	s.db.QueryRow(`SELECT last_viewed FROM paste_views WHERE paste_id=? AND viewer_id=?`,
+		row.ID, viewerID).Scan(&last)
+	if last.Valid && now-last.Int64 < int64(burnWindowMinutes)*60 {
+		r := int(row.ReadsLimit.Int64) - row.ReadsUsed
+		if r < 0 {
+			r = 0
+		}
+		return &r, false
+	}
+	s.db.Exec(`INSERT INTO paste_views (paste_id, viewer_id, last_viewed) VALUES (?,?,?)
+		ON CONFLICT(paste_id, viewer_id) DO UPDATE SET last_viewed = excluded.last_viewed`,
+		row.ID, viewerID, now)
+	used := row.ReadsUsed + 1
+	s.db.Exec(`UPDATE pastes SET reads_used=? WHERE id=?`, used, row.ID)
+	if int64(used) >= row.ReadsLimit.Int64 {
+		s.SoftDelete(row.ID)
+	}
+	r := int(row.ReadsLimit.Int64) - int(used)
+	if r < 0 {
+		r = 0
+	}
+	return &r, true
+}
+
+// Burned reports whether a read-limited paste has exhausted its budget.
+func (row *PasteRow) Burned() bool {
+	return row.ReadsLimit.Valid && int64(row.ReadsUsed) >= row.ReadsLimit.Int64
+}
+
+func DeletionTokenEqual(stored, given string) bool {
+	return subtle.ConstantTimeCompare([]byte(stored), []byte(given)) == 1
+}

internal/store/customslug.go

@@ -0,0 +1,46 @@
+package store
+
+import (
+	"errors"
+	"regexp"
+	"strings"
+)
+
+var slugRE = regexp.MustCompile(`^[a-zA-Z0-9][a-zA-Z0-9-_]{0,63}$`)
+
+// reserved words that would collide with routes
+var reservedSlugs = map[string]bool{
+	"api": true, "raw": true, "can": true, "cans": true, "public": true,
+	"history": true, "static": true, "assets": true, "favicon.ico": true,
+	"new": true, "login": true, "logout": true, "admin": true, "settings": true,
+}
+
+var ErrInvalidSlug = errors.New("custom slug must be 1-64 chars: letters, digits, dash, underscore; must start with letter or digit")
+var ErrReservedSlug = errors.New("that slug is reserved")
+var ErrSlugTaken = errors.New("that slug is already taken")
+
+func ValidateCustomSlug(slug string) error {
+	if !slugRE.MatchString(slug) {
+		return ErrInvalidSlug
+	}
+	if reservedSlugs[strings.ToLower(slug)] {
+		return ErrReservedSlug
+	}
+	return nil
+}
+
+func (s *Store) SlugTaken(slug string) (bool, error) {
+	var n int
+	err := s.db.QueryRow(`SELECT COUNT(*) FROM pastes WHERE custom_slug = ? OR id = ?`, slug, slug).Scan(&n)
+	if err != nil {
+		return false, err
+	}
+	if n > 0 {
+		return true, nil
+	}
+	err = s.db.QueryRow(`SELECT COUNT(*) FROM paste_cans WHERE id = ?`, slug).Scan(&n)
+	if err != nil {
+		return false, err
+	}
+	return n > 0, nil
+}

internal/store/password.go

@@ -0,0 +1,52 @@
+package store
+
+import (
+	"crypto/rand"
+	"crypto/subtle"
+	"encoding/base64"
+	"fmt"
+	"strings"
+
+	"golang.org/x/crypto/argon2"
+)
+
+// argon2id with sane defaults
+const (
+	argonTime    = 1
+	argonMemory  = 64 * 1024
+	argonThreads = 4
+	argonKeyLen  = 32
+	argonSaltLen = 16
+)
+
+// Argon2IDHash hashes a password with argon2id.
+func Argon2IDHash(pw string) (string, error) {
+	salt := make([]byte, argonSaltLen)
+	if _, err := rand.Read(salt); err != nil {
+		return "", err
+	}
+	key := argon2.IDKey([]byte(pw), salt, argonTime, argonMemory, argonThreads, argonKeyLen)
+	return fmt.Sprintf("$argon2id$v=19$m=%d,t=%d,p=%d$%s$%s",
+		argonMemory, argonTime, argonThreads,
+		base64.RawStdEncoding.EncodeToString(salt), base64.RawStdEncoding.EncodeToString(key)), nil
+}
+
+func CheckPassword(hash, pw string) bool {
+	parts := strings.Split(hash, "$")
+	if len(parts) != 6 || parts[1] != "argon2id" {
+		return false
+	}
+	var m, t uint32
+	var p uint8
+	fmt.Sscanf(parts[3], "m=%d,t=%d,p=%d", &m, &t, &p)
+	salt, err1 := base64.RawStdEncoding.DecodeString(parts[4])
+	want, err2 := base64.RawStdEncoding.DecodeString(parts[5])
+	if err1 != nil || err2 != nil {
+		return false
+	}
+	got := argon2.IDKey([]byte(pw), salt, t, m, p, uint32(len(want)))
+	return subtle.ConstantTimeCompare(got, want) == 1
+}
+
+// cryptoRead is used by genSlug
+func cryptoRead(b []byte) (int, error) { return rand.Read(b) }

internal/store/store.go

@@ -0,0 +1,463 @@
+// Package store provides the SQLite persistence layer for palette: schema
+// migrations, the Store type and all queries, and the background sweeper.
+package store
+
+import (
+	"database/sql"
+	"errors"
+	"fmt"
+	"log"
+	"time"
+
+	_ "modernc.org/sqlite"
+)
+
+// SlugReservationDays is the default custom-URL reservation window (admin-tunable via settings, #40).
+const SlugReservationDays = 30
+
+// SoftDeleteGraceDays is how long soft-deleted pastes linger before hard delete.
+const SoftDeleteGraceDays = 7
+
+type Paste struct {
+	ID          string  `json:"id"`
+	CustomSlug  *string `json:"custom_slug,omitempty"`
+	Content     string  `json:"content"`
+	ContentType string  `json:"content_type"`
+	Language    *string `json:"language,omitempty"`
+	Title       *string `json:"title,omitempty"`
+	Password    *string `json:"password,omitempty"`
+	ExpiresIn   *string `json:"expires_in,omitempty"`
+	BurnAfterRead bool  `json:"burn_after_read,omitempty"`
+	BurnAfterReads *int `json:"burn_after_reads,omitempty"` // #49: readable N times (default 1)
+	Visibility  string  `json:"visibility"`
+	CanID       *string `json:"can_id,omitempty"`
+	CreatedAt   int64   `json:"created_at"`
+	DeletedAt   *int64  `json:"deleted_at,omitempty"`
+	ExpiresAt   *int64  `json:"expires_at,omitempty"`
+	ViewerID    string  `json:"-"` // set from vwr cookie server-side (#37)
+	readsLimit  *int64  // #49: resolved read budget, not serialized
+	ViewCount   int     `json:"view_count"`
+	DeletionToken string `json:"-"`
+}
+
+type PasteRow struct {
+	ID            string
+	CustomSlug    sql.NullString
+	Content       string
+	ContentType   string
+	Language      sql.NullString
+	Title         sql.NullString
+	PasswordHash  sql.NullString
+	ExpiresAt     sql.NullInt64
+	BurnAfterRead bool
+	ReadsLimit    sql.NullInt64
+	ReadsUsed     int
+	Visibility    string
+	CanID         sql.NullString
+	CreatedAt     int64
+	DeletedAt     sql.NullInt64
+	ViewCount     int
+	Size          int
+	DeletionToken sql.NullString
+	ViewerID      sql.NullString
+}
+
+type CanRow struct {
+	ID           string
+	Title        sql.NullString
+	Visibility   string
+	PasswordHash sql.NullString
+	CreatedAt    int64
+	DeletedAt    sql.NullInt64
+	ExpiresAt    sql.NullInt64
+}
+
+type Store struct {
+	db *sql.DB
+}
+
+func OpenStore(path string) (*Store, error) {
+	db, err := sql.Open("sqlite", path+"?_pragma=journal_mode(WAL)&_pragma=busy_timeout(5000)")
+	if err != nil {
+		return nil, err
+	}
+	s := &Store{db: db}
+	if err := s.migrate(); err != nil {
+		return nil, err
+	}
+	return s, nil
+}
+
+func (s *Store) migrate() error {
+	_, err := s.db.Exec(`
+	CREATE TABLE IF NOT EXISTS pastes (
+		id            TEXT PRIMARY KEY,
+		custom_slug   TEXT UNIQUE,
+		content       TEXT NOT NULL,
+		content_type  TEXT NOT NULL DEFAULT 'text/plain',
+		language      TEXT,
+		title         TEXT,
+		password_hash TEXT,
+		expires_at    INTEGER,
+		burn_after_read INTEGER DEFAULT 0,
+		visibility    TEXT NOT NULL DEFAULT 'public',
+		can_id        TEXT,
+		created_at    INTEGER NOT NULL,
+		deleted_at    INTEGER,
+		view_count    INTEGER NOT NULL DEFAULT 0,
+deletion_token TEXT
+	);
+	CREATE INDEX IF NOT EXISTS idx_pastes_visibility_created ON pastes(visibility, created_at DESC);
+	CREATE INDEX IF NOT EXISTS idx_pastes_expires ON pastes(expires_at) WHERE expires_at IS NOT NULL;
+	CREATE INDEX IF NOT EXISTS idx_pastes_deleted ON pastes(deleted_at) WHERE deleted_at IS NOT NULL;
+	CREATE TABLE IF NOT EXISTS paste_cans (
+		id            TEXT PRIMARY KEY,
+		title         TEXT,
+		description   TEXT,
+		visibility    TEXT NOT NULL DEFAULT 'public',
+		password_hash TEXT,
+		created_at    INTEGER NOT NULL,
+		deleted_at    INTEGER,
+		expires_at    INTEGER
+	);
+	`)
+	s.db.Exec(`ALTER TABLE pastes ADD COLUMN deletion_token TEXT`) // ignore if exists
+	s.db.Exec(`ALTER TABLE pastes ADD COLUMN viewer_id TEXT`)     // ignore if exists (#37)
+	s.db.Exec(`ALTER TABLE pastes ADD COLUMN reads_limit INTEGER`)          // ignore if exists (#49)
+	s.db.Exec(`ALTER TABLE pastes ADD COLUMN reads_used INTEGER DEFAULT 0`) // ignore if exists (#49)
+	s.db.Exec(`CREATE TABLE IF NOT EXISTS paste_views (
+		paste_id    TEXT NOT NULL,
+		viewer_id   TEXT NOT NULL,
+		last_viewed INTEGER NOT NULL,
+		PRIMARY KEY (paste_id, viewer_id)
+	)`) // #49: per-viewer read dedupe window
+	return err
+}
+
+// SlugAlphabet is the paste-id charset (no ambiguous chars).
+var SlugAlphabet = "23456789abcdefghjkmnpqrstuvwxyz"
+
+// genSlug generates a random slug of length n.
+func genSlug(n int) string {
+	b := make([]byte, n)
+	_, _ = cryptoRead(b)
+	for i := range b {
+		b[i] = SlugAlphabet[int(b[i])%len(SlugAlphabet)]
+	}
+	return string(b)
+}
+
+// validExpiry reports whether an expires_in duration is in the accepted
+// window. The UI restricts presets to 1 minute - 1 year (#48); the API must
+// enforce the same bounds, otherwise negative/zero/absurd durations create
+// pastes that are born expired (or effectively permanent).
+const (
+	minExpiry = time.Minute
+	maxExpiry = 366 * 24 * time.Hour // 1 year (+ leap day headroom)
+)
+
+func ValidExpiry(d time.Duration) bool {
+	return d >= minExpiry && d <= maxExpiry
+}
+
+func (s *Store) CreatePaste(p *Paste) (*Paste, error) {
+	id := genSlug(6)
+	now := time.Now().Unix()
+
+	var expiresAt *int64
+	if p.ExpiresIn != nil && *p.ExpiresIn != "" {
+		d, err := time.ParseDuration(*p.ExpiresIn)
+		if err != nil {
+			return nil, fmt.Errorf("invalid expires_in: %w", err)
+		}
+		if !ValidExpiry(d) {
+			return nil, fmt.Errorf("expires_in must be between 1 minute and 1 year")
+		}
+		t := now + int64(d.Seconds())
+		expiresAt = &t
+	}
+
+	var pwHash *string
+	if p.Password != nil && *p.Password != "" {
+		h, err := Argon2IDHash(*p.Password)
+		if err != nil {
+			return nil, err
+		}
+		pwHash = &h
+	}
+
+	if p.CustomSlug != nil && *p.CustomSlug != "" {
+		slug := *p.CustomSlug
+		if err := ValidateCustomSlug(slug); err != nil {
+			return nil, err
+		}
+		taken, err := s.SlugTaken(slug)
+		if err != nil {
+			return nil, err
+		}
+		if taken {
+			return nil, ErrSlugTaken
+		}
+	}
+
+	// #49: burn-after-read pastes carry a read budget (default 1 read)
+	if p.BurnAfterRead {
+		limit := int64(1)
+		if p.BurnAfterReads != nil && *p.BurnAfterReads > 0 {
+			limit = int64(*p.BurnAfterReads)
+		}
+		p.readsLimit = &limit
+	}
+
+	visibility := p.Visibility
+	if visibility == "" {
+		visibility = "public"
+	}
+	if visibility != "public" && visibility != "unlisted" {
+		return nil, errors.New("visibility must be public or unlisted")
+	}
+
+	contentType := p.ContentType
+	if contentType == "" {
+		contentType = "text/plain"
+	}
+
+	var slugVal *string
+	if p.CustomSlug != nil && *p.CustomSlug != "" {
+		slugVal = p.CustomSlug
+	}
+	p.DeletionToken = genDeletionToken()
+	_, err := s.db.Exec(`INSERT INTO pastes
+		(id, custom_slug, content, content_type, language, title, password_hash, expires_at, burn_after_read, visibility, created_at, deletion_token, viewer_id, reads_limit)
+		VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?)`,
+		id, slugVal, p.Content, contentType, p.Language, p.Title, pwHash, expiresAt, boolToInt(p.BurnAfterRead), visibility, now, p.DeletionToken, p.ViewerID, p.readsLimit)
+	if err != nil {
+		return nil, err
+	}
+	p.ID = id
+	p.CreatedAt = now
+	p.ExpiresAt = expiresAt
+	p.Visibility = visibility
+	return p, nil
+}
+
+func (s *Store) GetPaste(idOrSlug string) (*PasteRow, error) {
+	row := s.db.QueryRow(`SELECT id, custom_slug, content, content_type, language, title, password_hash, expires_at, burn_after_read, visibility, can_id, created_at, deleted_at, view_count, deletion_token, viewer_id, reads_limit, COALESCE(reads_used, 0)
+		FROM pastes WHERE (id = ? OR custom_slug = ?) AND deleted_at IS NULL`, idOrSlug, idOrSlug)
+	var r PasteRow
+	err := row.Scan(&r.ID, &r.CustomSlug, &r.Content, &r.ContentType, &r.Language, &r.Title, &r.PasswordHash, &r.ExpiresAt, &r.BurnAfterRead, &r.Visibility, &r.CanID, &r.CreatedAt, &r.DeletedAt, &r.ViewCount, &r.DeletionToken, &r.ViewerID, &r.ReadsLimit, &r.ReadsUsed)
+	if err == sql.ErrNoRows {
+		return nil, nil
+	}
+	return &r, err
+}
+
+func (s *Store) ListPublic(limit, offset int) ([]PasteRow, int, error) {
+	rows, err := s.db.Query(`SELECT id, custom_slug, content_type, language, title, visibility, created_at, view_count, LENGTH(content) FROM pastes
+		WHERE visibility='public' AND deleted_at IS NULL AND can_id IS NULL AND (expires_at IS NULL OR expires_at > ?)
+		ORDER BY created_at DESC LIMIT ? OFFSET ?`, time.Now().Unix(), limit, offset)
+	if err != nil {
+		return nil, 0, err
+	}
+	defer rows.Close()
+	var out []PasteRow
+	for rows.Next() {
+		var r PasteRow
+		var cs, lang, title sql.NullString
+		if err := rows.Scan(&r.ID, &cs, &r.ContentType, &lang, &title, &r.Visibility, &r.CreatedAt, &r.ViewCount, &r.Size); err != nil {
+			return nil, 0, err
+		}
+		r.CustomSlug = cs
+		r.Language = lang
+		r.Title = title
+		out = append(out, r)
+	}
+	var total int
+	s.db.QueryRow(`SELECT COUNT(*) FROM pastes WHERE visibility='public' AND deleted_at IS NULL AND can_id IS NULL AND (expires_at IS NULL OR expires_at > ?)`, time.Now().Unix()).Scan(&total)
+	return out, total, nil
+}
+
+// ListMine lists pastes created from the given viewer id (browser cookie), newest first.
+func (s *Store) ListMine(viewerID string, limit, offset int) ([]PasteRow, int, error) {
+	rows, err := s.db.Query(`SELECT id, custom_slug, language, title, visibility, created_at, view_count, LENGTH(content)
+		FROM pastes
+		WHERE viewer_id = ? AND deleted_at IS NULL AND can_id IS NULL AND (expires_at IS NULL OR expires_at > ?)
+		ORDER BY created_at DESC LIMIT ? OFFSET ?`, viewerID, time.Now().Unix(), limit, offset)
+	if err != nil {
+		return nil, 0, err
+	}
+	defer rows.Close()
+	var out []PasteRow
+	for rows.Next() {
+		var r PasteRow
+		var cs, lang, title sql.NullString
+		if err := rows.Scan(&r.ID, &cs, &lang, &title, &r.Visibility, &r.CreatedAt, &r.ViewCount, &r.Size); err != nil {
+			return nil, 0, err
+		}
+		r.CustomSlug, r.Language, r.Title = cs, lang, title
+		out = append(out, r)
+	}
+	var total int
+	s.db.QueryRow(`SELECT COUNT(*) FROM pastes
+		WHERE viewer_id = ? AND deleted_at IS NULL AND can_id IS NULL AND (expires_at IS NULL OR expires_at > ?)`,
+		viewerID, time.Now().Unix()).Scan(&total)
+	return out, total, nil
+}
+
+// MineOwner returns the stored viewer_id for a paste, or "" if none.
+func (s *Store) MineOwner(id string) (string, error) {
+	var vid sql.NullString
+	err := s.db.QueryRow(`SELECT viewer_id FROM pastes WHERE id = ? AND deleted_at IS NULL`, id).Scan(&vid)
+	if err == sql.ErrNoRows {
+		return "", nil
+	}
+	if err != nil {
+		return "", err
+	}
+	if !vid.Valid {
+		return "", nil
+	}
+	return vid.String, nil
+}
+
+func (s *Store) SoftDelete(id string) error {
+	_, err := s.db.Exec(`UPDATE pastes SET deleted_at=? WHERE id=? AND deleted_at IS NULL`, time.Now().Unix(), id)
+	return err
+}
+
+func (s *Store) IncrementViews(id string) {
+	s.db.Exec(`UPDATE pastes SET view_count = view_count + 1 WHERE id = ?`, id)
+}
+
+// SweepExpired soft-deletes expired pastes and hard-deletes soft-deleted pastes past grace.
+func (s *Store) SweepExpired() {
+	now := time.Now().Unix()
+	s.db.Exec(`UPDATE pastes SET deleted_at=? WHERE expires_at IS NOT NULL AND expires_at < ? AND deleted_at IS NULL`, now, now)
+	grace := now - SoftDeleteGraceDays*86400
+	s.db.Exec(`DELETE FROM pastes WHERE deleted_at IS NOT NULL AND deleted_at < ?`, grace)
+}
+
+// ReleaseCustomSlugs frees custom URLs so they can be reused:
+//   - pastes whose expires_at has passed (expired or soft-deleted/expired),
+//   - pastes created more than reservationDays days ago (custom URLs are a
+//     reservation, not permanent).
+//
+// It returns the number of pastes whose custom_slug was released.
+func (s *Store) ReleaseCustomSlugs(reservationDays int) (int64, error) {
+	now := time.Now().Unix()
+	res, err := s.db.Exec(`UPDATE pastes SET custom_slug = NULL
+		WHERE custom_slug IS NOT NULL
+		  AND (expires_at IS NOT NULL AND expires_at > 0 AND expires_at < ?
+		   OR created_at < ?)`,
+		now, now-int64(reservationDays)*86400)
+	if err != nil {
+		return 0, err
+	}
+	n, _ := res.RowsAffected()
+	if n > 0 {
+		log.Printf("released %d custom slug(s)", n)
+	}
+	return n, nil
+}
+
+func (s *Store) StartSweeper(every time.Duration, reservationDays int) {
+	go func() {
+		t := time.NewTicker(every)
+		for range t.C {
+			s.SweepExpired()
+			s.ReleaseCustomSlugs(reservationDays)
+		}
+	}()
+}
+
+func boolToInt(b bool) int {
+	if b {
+		return 1
+	}
+	return 0
+}
+
+func NullStrPtr(ns sql.NullString) *string {
+	if ns.Valid {
+		return &ns.String
+	}
+	return nil
+}
+
+// HardDelete removes a paste row entirely (deletion-token redeem).
+func (s *Store) HardDelete(id string) {
+	s.db.Exec(`DELETE FROM pastes WHERE id = ?`, id)
+}
+
+// InsertCan creates a paste_can row.
+func (s *Store) InsertCan(canID, title, description, visibility string, pwHash *string, createdAt int64, expiresAt *int64) error {
+	_, err := s.db.Exec(`INSERT INTO paste_cans (id, title, description, visibility, password_hash, created_at, expires_at)
+		VALUES (?,?,?,?,?,?,?)`, canID, title, description, visibility, pwHash, createdAt, expiresAt)
+	return err
+}
+
+// DeleteCan removes an (empty/aborted) can row.
+func (s *Store) DeleteCan(canID string) {
+	s.db.Exec(`DELETE FROM paste_cans WHERE id=?`, canID)
+}
+
+// InsertCanItem adds an item paste belonging to a can.
+func (s *Store) InsertCanItem(canID, title, content, contentType string, language *string, expiresAt, binary *string, now int64) error {
+	// language/expiresAt unused here for now; content stored as text (binary-safe in sqlite)
+	_, err := s.db.Exec(`INSERT INTO pastes
+		(id, content, content_type, language, title, visibility, can_id, created_at)
+		VALUES (?,?,?,?,?,?,?,?)`,
+		genSlug(6), content, contentType, language, &title, "unlisted", canID, now)
+	_ = expiresAt
+	_ = binary
+	return err
+}
+
+func (s *Store) GetCan(id string) (*CanRow, error) {
+	row := s.db.QueryRow(`SELECT id, title, visibility, password_hash, created_at, deleted_at, expires_at
+		FROM paste_cans WHERE id = ? AND deleted_at IS NULL`, id)
+	var c CanRow
+	err := row.Scan(&c.ID, &c.Title, &c.Visibility, &c.PasswordHash, &c.CreatedAt, &c.DeletedAt, &c.ExpiresAt)
+	if err == sql.ErrNoRows {
+		return nil, nil
+	}
+	return &c, err
+}
+
+func (s *Store) ListCanItems(canID string) ([]PasteRow, error) {
+	rows, err := s.db.Query(`SELECT id, custom_slug, content, content_type, language, title, password_hash, expires_at, burn_after_read, visibility, can_id, created_at, deleted_at, view_count
+		FROM pastes WHERE can_id = ? AND deleted_at IS NULL ORDER BY created_at ASC`, canID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []PasteRow
+	for rows.Next() {
+		var r PasteRow
+		if err := rows.Scan(&r.ID, &r.CustomSlug, &r.Content, &r.ContentType, &r.Language, &r.Title, &r.PasswordHash, &r.ExpiresAt, &r.BurnAfterRead, &r.Visibility, &r.CanID, &r.CreatedAt, &r.DeletedAt, &r.ViewCount); err != nil {
+			return nil, err
+		}
+		out = append(out, r)
+	}
+	return out, nil
+}
+
+// GenSlug is the exported slug generator.
+func GenSlug(n int) string { return genSlug(n) }
+
+// Exec runs a raw statement (test helper).
+func (s *Store) Exec(query string, args ...any) (int64, error) {
+	res, err := s.db.Exec(query, args...)
+	if err != nil {
+		return 0, err
+	}
+	n, _ := res.RowsAffected()
+	return n, nil
+}
+
+// QueryInt runs a query returning a single integer (test helper).
+func (s *Store) QueryInt(query string, args ...any) int {
+	var n int
+	s.db.QueryRow(query, args...).Scan(&n)
+	return n
+}