Refactor Store into SessionStore; move domain SQL onto User/Question/Answer.

2026-08-22 02:40:51 -07:00
parent f31f352838
commit c77298411e
15 changed files with 696 additions and 876 deletions
@@ -0,0 +1,183 @@
+package store
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/google/uuid"
+)
+
+// ErrLastAdmin is returned when demoting the only remaining admin.
+var ErrLastAdmin = errors.New("cannot demote the last admin")
+
+// Role is a user privilege level stored in users.role.
+type Role string
+
+const (
+	RoleUser  Role = "user"
+	RoleAdmin Role = "admin"
+)
+
+// User is an account row. Methods run SQL against db.
+type User struct {
+	ID           string
+	Username     string
+	Name         string
+	Role         Role
+	AvatarURL    string
+	State        string
+	CreatedAt    string
+	PasswordHash string
+	db           *sql.DB
+}
+
+// NewUser returns a User bound to db (not yet inserted).
+func NewUser(db *sql.DB) *User {
+	return &User{db: db}
+}
+
+func (u *User) Admin() bool {
+	return u != nil && u.Role == RoleAdmin
+}
+
+func NormalizeUsername(s string) string {
+	return strings.ToLower(strings.TrimSpace(s))
+}
+
+// Create inserts the user. Sets ID, Name, and CreatedAt when empty.
+func (u *User) Create(ctx context.Context) error {
+	if u == nil || u.db == nil {
+		return fmt.Errorf("user: no database")
+	}
+	if u.Role != RoleUser && u.Role != RoleAdmin {
+		return fmt.Errorf("invalid role")
+	}
+	u.Username = NormalizeUsername(u.Username)
+	if u.ID == "" {
+		u.ID = uuid.NewString()
+	}
+	if u.Name == "" {
+		u.Name = u.Username
+	}
+	if u.CreatedAt == "" {
+		u.CreatedAt = time.Now().UTC().Format(time.RFC3339)
+	}
+	_, err := u.db.ExecContext(ctx, `INSERT INTO users (id, username, name, password_hash, role, avatar_url, state, created_at) VALUES ($1, $2, $3, $4, $5, '', '', $6)`,
+		u.ID, u.Username, u.Name, u.PasswordHash, string(u.Role), u.CreatedAt)
+	return err
+}
+
+// SetRole updates this user's role (last-admin safe).
+func (u *User) SetRole(ctx context.Context, role Role) error {
+	if u == nil || u.db == nil {
+		return fmt.Errorf("user: no database")
+	}
+	if role != RoleUser && role != RoleAdmin {
+		return fmt.Errorf("invalid role")
+	}
+	tx, err := u.db.BeginTx(ctx, nil)
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+
+	var current string
+	err = tx.QueryRowContext(ctx, `SELECT role FROM users WHERE id = $1`, u.ID).Scan(&current)
+	if err != nil {
+		return err
+	}
+	if Role(current) == RoleAdmin && role == RoleUser {
+		var n int
+		if err := tx.QueryRowContext(ctx, `SELECT COUNT(*) FROM users WHERE role = $1`, string(RoleAdmin)).Scan(&n); err != nil {
+			return err
+		}
+		if n <= 1 {
+			return ErrLastAdmin
+		}
+	}
+	res, err := tx.ExecContext(ctx, `UPDATE users SET role = $1 WHERE id = $2`, string(role), u.ID)
+	if err != nil {
+		return err
+	}
+	aff, err := res.RowsAffected()
+	if err != nil {
+		return err
+	}
+	if aff == 0 {
+		return sql.ErrNoRows
+	}
+	if err := tx.Commit(); err != nil {
+		return err
+	}
+	u.Role = role
+	return nil
+}
+
+// SaveProfile writes State and optionally AvatarURL.
+func (u *User) SaveProfile(ctx context.Context) error {
+	if u == nil || u.db == nil {
+		return fmt.Errorf("user: no database")
+	}
+	u.State = strings.TrimSpace(u.State)
+	if u.AvatarURL == "" {
+		_, err := u.db.ExecContext(ctx, `UPDATE users SET state = $1 WHERE id = $2`, u.State, u.ID)
+		return err
+	}
+	_, err := u.db.ExecContext(ctx, `UPDATE users SET state = $1, avatar_url = $2 WHERE id = $3`, u.State, u.AvatarURL, u.ID)
+	return err
+}
+
+func CountAdmins(ctx context.Context, db *sql.DB) (int, error) {
+	var n int
+	err := db.QueryRowContext(ctx, `SELECT COUNT(*) FROM users WHERE role = $1`, string(RoleAdmin)).Scan(&n)
+	return n, err
+}
+
+func ListUsers(ctx context.Context, db *sql.DB) ([]User, error) {
+	rows, err := db.QueryContext(ctx, `SELECT id, username, name, role, avatar_url, state, created_at FROM users ORDER BY created_at ASC`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []User
+	for rows.Next() {
+		var u User
+		var role string
+		if err := rows.Scan(&u.ID, &u.Username, &u.Name, &role, &u.AvatarURL, &u.State, &u.CreatedAt); err != nil {
+			return nil, err
+		}
+		u.Role = Role(role)
+		u.db = db
+		out = append(out, u)
+	}
+	return out, rows.Err()
+}
+
+func UserByID(ctx context.Context, db *sql.DB, id string) (*User, error) {
+	return scanUser(db, db.QueryRowContext(ctx, `SELECT id, username, name, role, avatar_url, state, created_at FROM users WHERE id = $1`, id), false)
+}
+
+func UserByUsername(ctx context.Context, db *sql.DB, username string) (*User, error) {
+	return scanUser(db, db.QueryRowContext(ctx, `SELECT id, username, name, role, avatar_url, state, created_at, password_hash FROM users WHERE username = $1`, NormalizeUsername(username)), true)
+}
+
+func scanUser(db *sql.DB, row *sql.Row, withSecrets bool) (*User, error) {
+	var u User
+	var role string
+	var err error
+	if withSecrets {
+		err = row.Scan(&u.ID, &u.Username, &u.Name, &role, &u.AvatarURL, &u.State, &u.CreatedAt, &u.PasswordHash)
+	} else {
+		err = row.Scan(&u.ID, &u.Username, &u.Name, &role, &u.AvatarURL, &u.State, &u.CreatedAt)
+	}
+	if err != nil {
+		return nil, err
+	}
+	u.Role = Role(role)
+	u.db = db
+	return &u, nil
+}