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feat: release v0.1.3 chat, profiles, and media

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Keep read receipts for the other person only, and let photos, voice, and files stay cached until they are actually replaced.
This commit is contained in:
ahp
2026-10-09 19:05:59 +03:30
parent 3cce2158e9
commit d9a2abb44f
45 changed files with 2337 additions and 573 deletions
Download Patch File Download Diff File Expand all files Collapse all files
backend/internal/store/invites.go
+6 -3
View File
@@ -146,7 +146,7 @@ func (s *Store) CreateRegistrationInvite(
return scanInvite(row)
}
func (s *Store) ListRegistrationInvites(ctx context.Context, query string, limit, offset int) ([]models.RegistrationInvite, int64, error) {
func (s *Store) ListRegistrationInvites(ctx context.Context, query, status string, limit, offset int) ([]models.RegistrationInvite, int64, error) {
if limit <= 0 {
limit = 10
}
@@ -157,18 +157,21 @@ func (s *Store) ListRegistrationInvites(ctx context.Context, query string, limit
offset = 0
}
query = strings.TrimSpace(query)
status = strings.TrimSpace(status)
var total int64
if err := s.pool.QueryRow(ctx, `
SELECT COUNT(*) FROM registration_invites
WHERE ($1 = '' OR COALESCE(label, '') ILIKE '%'||$1||'%')`, query).Scan(&total); err != nil {
WHERE ($1 = '' OR COALESCE(label, '') ILIKE '%'||$1||'%')
AND ($2 = '' OR status = $2)`, query, status).Scan(&total); err != nil {
return nil, 0, err
}
rows, err := s.pool.Query(ctx, `
SELECT `+inviteCols+`
FROM registration_invites
WHERE ($1 = '' OR COALESCE(label, '') ILIKE '%'||$1||'%')
AND ($2 = '' OR status = $2)
ORDER BY created_at DESC
LIMIT $2 OFFSET $3`, query, limit, offset)
LIMIT $3 OFFSET $4`, query, status, limit, offset)
if err != nil {
return nil, 0, err
}
backend/internal/store/learning.go
+85 -58
View File
@@ -7,17 +7,17 @@ import (
// LearningOverview is cohort-level learning analytics for staff.
type LearningOverview struct {
StudentsActive int64 `json:"studentsActive"`
StudentsLocked int64 `json:"studentsLocked"`
StudentsTotal int64 `json:"studentsTotal"`
LessonsTotal int64 `json:"lessonsTotal"`
Completions int64 `json:"completions"`
Attempts7d int64 `json:"attempts7d"`
Passes7d int64 `json:"passes7d"`
PassRate7d float64 `json:"passRate7d"`
AvgWatchPct float64 `json:"avgWatchPct"`
XPAwarded7d int64 `json:"xpAwarded7d"`
StudentsStreaking int64 `json:"studentsStreaking"`
StudentsActive int64 `json:"studentsActive"`
StudentsLocked int64 `json:"studentsLocked"`
StudentsTotal int64 `json:"studentsTotal"`
LessonsTotal int64 `json:"lessonsTotal"`
Completions int64 `json:"completions"`
Attempts7d int64 `json:"attempts7d"`
Passes7d int64 `json:"passes7d"`
PassRate7d float64 `json:"passRate7d"`
AvgWatchPct float64 `json:"avgWatchPct"`
XPAwarded7d int64 `json:"xpAwarded7d"`
StudentsStreaking int64 `json:"studentsStreaking"`
}
func (s *Store) LearningOverview(ctx context.Context) (*LearningOverview, error) {
@@ -81,10 +81,40 @@ type StudentLearningRow struct {
LastActivityAt *time.Time `json:"lastActivityAt,omitempty"`
}
func (s *Store) ListStudentLearning(ctx context.Context, q string) ([]StudentLearningRow, error) {
func (s *Store) ListStudentLearning(ctx context.Context, q, filter, sort string, limit, offset int) ([]StudentLearningRow, int64, error) {
if limit <= 0 {
limit = 10
}
if limit > 100 {
limit = 100
}
if offset < 0 {
offset = 0
}
var lessonsTotal int64
if err := s.pool.QueryRow(ctx, `SELECT count(*) FROM lessons WHERE is_active`).Scan(&lessonsTotal); err != nil {
return nil, err
return nil, 0, err
}
where := `u.role = 'student'
AND ($1 = '' OR u.name ILIKE '%'||$1||'%' OR u.username ILIKE '%'||$1||'%' OR u.email ILIKE '%'||$1||'%')`
switch filter {
case "active":
where += ` AND u.is_active AND NOT u.is_locked`
case "locked":
where += ` AND u.is_locked`
}
order := `u.xp DESC, u.id ASC`
switch sort {
case "progress":
order = `COALESCE(p.passed, 0) DESC, u.id ASC`
case "streak":
order = `u.streak_current DESC, u.id ASC`
case "activity":
order = `u.last_activity_date DESC NULLS LAST, u.id ASC`
}
var total int64
if err := s.pool.QueryRow(ctx, `SELECT COUNT(*) FROM users u WHERE `+where, q).Scan(&total); err != nil {
return nil, 0, err
}
rows, err := s.pool.Query(ctx, `
SELECT u.id, u.name, u.username, u.email, u.xp, u.hearts, u.streak_current,
@@ -105,12 +135,11 @@ func (s *Store) ListStudentLearning(ctx context.Context, q string) ([]StudentLea
WHERE created_at >= now() - interval '7 days'
GROUP BY user_id
) a ON a.user_id = u.id
WHERE u.role = 'student'
AND ($1 = '' OR u.name ILIKE '%'||$1||'%' OR u.username ILIKE '%'||$1||'%' OR u.email ILIKE '%'||$1||'%')
ORDER BY u.xp DESC, u.id ASC
LIMIT 500`, q)
WHERE `+where+`
ORDER BY `+order+`
LIMIT $2 OFFSET $3`, q, limit, offset)
if err != nil {
return nil, err
return nil, 0, err
}
defer rows.Close()
out := make([]StudentLearningRow, 0)
@@ -122,7 +151,7 @@ func (s *Store) ListStudentLearning(ctx context.Context, q string) ([]StudentLea
&r.IsLocked, &r.IsActive, &r.LastActivityAt,
&r.LessonsPassed, &r.Attempts7d, &r.Passes7d,
); err != nil {
return nil, err
return nil, 0, err
}
if r.LessonsTotal > 0 {
r.ProgressPct = float64(r.LessonsPassed) / float64(r.LessonsTotal) * 100
@@ -132,21 +161,21 @@ func (s *Store) ListStudentLearning(ctx context.Context, q string) ([]StudentLea
}
out = append(out, r)
}
return out, rows.Err()
return out, total, rows.Err()
}
type LessonLearningDetail struct {
LessonID int64 `json:"lessonId"`
ChapterID int64 `json:"chapterId"`
ChapterTitle string `json:"chapterTitle"`
Title string `json:"title"`
SortOrder int `json:"sortOrder"`
WatchedPct float64 `json:"watchedPct"`
QuizUnlocked bool `json:"quizUnlocked"`
PassedQuiz bool `json:"passedQuiz"`
QuizCompletedAt *time.Time `json:"quizCompletedAt,omitempty"`
LastAttemptStatus string `json:"lastAttemptStatus,omitempty"`
LastAttemptScore float64 `json:"lastAttemptScore,omitempty"`
LessonID int64 `json:"lessonId"`
ChapterID int64 `json:"chapterId"`
ChapterTitle string `json:"chapterTitle"`
Title string `json:"title"`
SortOrder int `json:"sortOrder"`
WatchedPct float64 `json:"watchedPct"`
QuizUnlocked bool `json:"quizUnlocked"`
PassedQuiz bool `json:"passedQuiz"`
QuizCompletedAt *time.Time `json:"quizCompletedAt,omitempty"`
LastAttemptStatus string `json:"lastAttemptStatus,omitempty"`
LastAttemptScore float64 `json:"lastAttemptScore,omitempty"`
}
type AttemptLearningDetail struct {
@@ -178,11 +207,11 @@ type WatchSessionDetail struct {
}
type UserLearningDetail struct {
User StudentLearningRow `json:"user"`
Lessons []LessonLearningDetail `json:"lessons"`
Attempts []AttemptLearningDetail `json:"attempts"`
XPEvents []XPEventDetail `json:"xpEvents"`
Sessions []WatchSessionDetail `json:"sessions"`
User StudentLearningRow `json:"user"`
Lessons []LessonLearningDetail `json:"lessons"`
Attempts []AttemptLearningDetail `json:"attempts"`
XPEvents []XPEventDetail `json:"xpEvents"`
Sessions []WatchSessionDetail `json:"sessions"`
}
func (s *Store) UserLearningDetail(ctx context.Context, userID int64) (*UserLearningDetail, error) {
@@ -190,30 +219,28 @@ func (s *Store) UserLearningDetail(ctx context.Context, userID int64) (*UserLear
if err != nil {
return nil, err
}
list, err := s.ListStudentLearning(ctx, "")
if err != nil {
row := StudentLearningRow{
ID: u.ID, Name: u.Name, Username: u.Username, Email: u.Email,
XP: u.XP, Hearts: u.Hearts, StreakCurrent: u.StreakCurrent,
IsLocked: u.IsLocked, IsActive: u.IsActive, LastActivityAt: u.LastActivityDate,
}
if err := s.pool.QueryRow(ctx, `SELECT count(*) FROM lessons WHERE is_active`).Scan(&row.LessonsTotal); err != nil {
return nil, err
}
var row StudentLearningRow
found := false
for _, r := range list {
if r.ID == userID {
row = r
found = true
break
}
if err := s.pool.QueryRow(ctx, `SELECT count(*) FROM lesson_progress WHERE user_id=$1 AND passed_quiz`, userID).Scan(&row.LessonsPassed); err != nil {
return nil, err
}
if !found {
row = StudentLearningRow{
ID: u.ID, Name: u.Name, Username: u.Username, Email: u.Email,
XP: u.XP, Hearts: u.Hearts, StreakCurrent: u.StreakCurrent,
IsLocked: u.IsLocked, IsActive: u.IsActive, LastActivityAt: u.LastActivityDate,
}
_ = s.pool.QueryRow(ctx, `SELECT count(*) FROM lessons WHERE is_active`).Scan(&row.LessonsTotal)
_ = s.pool.QueryRow(ctx, `SELECT count(*) FROM lesson_progress WHERE user_id=$1 AND passed_quiz`, userID).Scan(&row.LessonsPassed)
if row.LessonsTotal > 0 {
row.ProgressPct = float64(row.LessonsPassed) / float64(row.LessonsTotal) * 100
}
if row.LessonsTotal > 0 {
row.ProgressPct = float64(row.LessonsPassed) / float64(row.LessonsTotal) * 100
}
if err := s.pool.QueryRow(ctx, `
SELECT COUNT(*), COUNT(*) FILTER (WHERE status='passed')
FROM quiz_attempts
WHERE user_id=$1 AND created_at >= now() - interval '7 days'`, userID).Scan(&row.Attempts7d, &row.Passes7d); err != nil {
return nil, err
}
if row.Attempts7d > 0 {
row.PassRate7d = float64(row.Passes7d) / float64(row.Attempts7d) * 100
}
detail := &UserLearningDetail{User: row, Lessons: []LessonLearningDetail{}, Attempts: []AttemptLearningDetail{}, XPEvents: []XPEventDetail{}, Sessions: []WatchSessionDetail{}}
@@ -221,7 +248,7 @@ func (s *Store) UserLearningDetail(ctx context.Context, userID int64) (*UserLear
lrows, err := s.pool.Query(ctx, `
SELECT l.id, l.chapter_id, c.title, l.title, l.sort_order,
COALESCE(p.watched_pct, 0), COALESCE(p.quiz_unlocked, false), COALESCE(p.passed_quiz, false), p.quiz_completed_at,
COALESCE(la.status, ''), COALESCE(la.score_pct, 0)
COALESCE(la.status::text, ''), COALESCE(la.score_pct, 0)
FROM lessons l
JOIN chapters c ON c.id = l.chapter_id
LEFT JOIN lesson_progress p ON p.lesson_id = l.id AND p.user_id = $1
backend/internal/store/learning_test.go
+1 -1
View File
@@ -28,7 +28,7 @@ func TestLearningOverviewSmoke(t *testing.T) {
if o == nil {
t.Fatal("nil overview")
}
students, err := st.ListStudentLearning(ctx, "")
students, _, err := st.ListStudentLearning(ctx, "", "", "xp", 10, 0)
if err != nil {
t.Fatal(err)
}
backend/internal/store/store.go
+91 -26
View File
@@ -504,7 +504,26 @@ func (s *Store) GetPhysicalOrder(ctx context.Context, id int64) (*models.Certifi
return scanPhysicalOrder(row)
}
func (s *Store) ListPhysicalOrders(ctx context.Context, status string) ([]models.CertificatePhysicalOrder, error) {
func (s *Store) ListPhysicalOrders(ctx context.Context, status string, limit, offset int) ([]models.CertificatePhysicalOrder, int64, error) {
if limit <= 0 {
limit = 10
}
if limit > 100 {
limit = 100
}
if offset < 0 {
offset = 0
}
where := ""
args := []any{}
if status != "" {
where = ` WHERE o.status=$1`
args = append(args, status)
}
var total int64
if err := s.pool.QueryRow(ctx, `SELECT COUNT(*) FROM certificate_physical_orders o`+where, args...).Scan(&total); err != nil {
return nil, 0, err
}
q := `
SELECT o.id, o.certificate_id, o.user_id, o.status, o.note,
o.recipient_name, o.phone, o.address, o.city, o.postal_code, o.tracking_code,
@@ -512,16 +531,11 @@ func (s *Store) ListPhysicalOrders(ctx context.Context, status string) ([]models
u.name, c.public_id
FROM certificate_physical_orders o
JOIN users u ON u.id = o.user_id
JOIN certificates c ON c.id = o.certificate_id`
args := []any{}
if status != "" {
q += ` WHERE o.status=$1`
args = append(args, status)
}
q += ` ORDER BY o.created_at DESC LIMIT 200`
JOIN certificates c ON c.id = o.certificate_id` + where + ` ORDER BY o.created_at DESC LIMIT $` + strconv.Itoa(len(args)+1) + ` OFFSET $` + strconv.Itoa(len(args)+2)
args = append(args, limit, offset)
rows, err := s.pool.Query(ctx, q, args...)
if err != nil {
return nil, err
return nil, 0, err
}
defer rows.Close()
out := make([]models.CertificatePhysicalOrder, 0)
@@ -530,11 +544,11 @@ func (s *Store) ListPhysicalOrders(ctx context.Context, status string) ([]models
if err := rows.Scan(&o.ID, &o.CertificateID, &o.UserID, &o.Status, &o.Note,
&o.RecipientName, &o.Phone, &o.Address, &o.City, &o.PostalCode, &o.TrackingCode,
&o.WindowEndsAt, &o.CreatedAt, &o.UpdatedAt, &o.UserName, &o.PublicID); err != nil {
return nil, err
return nil, 0, err
}
out = append(out, o)
}
return out, rows.Err()
return out, total, rows.Err()
}
func (s *Store) UpdatePhysicalOrder(ctx context.Context, id int64, status models.PhysicalOrderStatus, note, tracking string) (*models.CertificatePhysicalOrder, error) {
@@ -1069,7 +1083,7 @@ func (s *Store) AddChatMessage(ctx context.Context, userID, mentorID int64, send
INSERT INTO chat_messages (user_id, mentor_id, sender_role, body, reply_to, attachment_type, attachment_url, attachment_name, attachment_size)
VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9)
RETURNING id, user_id, mentor_id, sender_role, body, read_at, created_at, reply_to,
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at`,
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at, edited_at`,
userID, mentorID, senderRole.String(), body, replyTo, attType, attURL, attName, attSize)
return scanMessage(row)
}
@@ -1094,7 +1108,7 @@ func (s *Store) ImportChatMessage(ctx context.Context, userID, mentorID int64, s
INSERT INTO chat_messages (user_id, mentor_id, sender_role, body, attachment_type, attachment_url, attachment_name, attachment_size, created_at, pinned_at)
VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9,$10)
RETURNING id, user_id, mentor_id, sender_role, body, read_at, created_at, reply_to,
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at`,
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at, edited_at`,
userID, mentorID, senderRole.String(), body, attType, attURL, attName, attSize, createdAt, pinnedAt)
return scanMessage(row)
}
@@ -1138,6 +1152,48 @@ func (s *Store) DeleteChatMessage(ctx context.Context, meID, partnerID, msgID in
return tag.RowsAffected() > 0, nil
}
// ReplaceChatAttachment swaps the photo, video, or voice on one of my messages and marks it edited.
// The new type must match the current attachment.
func (s *Store) ReplaceChatAttachment(ctx context.Context, meID, partnerID, msgID int64, meRole models.Role, body, attType, attURL, attName string, attSize int64) (*models.ChatMessage, error) {
row := s.pool.QueryRow(ctx, `
UPDATE chat_messages
SET body=$1, edited_at=now(),
attachment_type=$2, attachment_url=$3, attachment_name=$4, attachment_size=$5
WHERE id=$6
AND ((user_id=$7 AND mentor_id=$8) OR (user_id=$8 AND mentor_id=$7))
AND sender_role=$9
AND (user_id=$7 OR mentor_id=$7)
AND attachment_type=$2
RETURNING id, user_id, mentor_id, sender_role, body, read_at, created_at, reply_to,
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at, edited_at`,
body, attType, attURL, attName, attSize, msgID, meID, partnerID, meRole.String())
m, err := scanMessage(row)
if errors.Is(err, pgx.ErrNoRows) {
return nil, ErrNotFound
}
return m, err
}
// EditChatMessage replaces the body of one of my own messages in this conversation.
func (s *Store) EditChatMessage(ctx context.Context, meID, partnerID, msgID int64, meRole models.Role, body string) (*models.ChatMessage, error) {
row := s.pool.QueryRow(ctx, `
UPDATE chat_messages
SET body=$1, edited_at=now()
WHERE id=$2
AND ((user_id=$3 AND mentor_id=$4) OR (user_id=$4 AND mentor_id=$3))
AND sender_role=$5
AND (user_id=$3 OR mentor_id=$3)
AND ($1 <> '' OR attachment_url IS NOT NULL)
RETURNING id, user_id, mentor_id, sender_role, body, read_at, created_at, reply_to,
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at, edited_at`,
body, msgID, meID, partnerID, meRole.String())
m, err := scanMessage(row)
if errors.Is(err, pgx.ErrNoRows) {
return nil, ErrNotFound
}
return m, err
}
const maxPinnedMessages = 3
// TogglePinChatMessage pins or unpins a message. If already at the pin limit,
@@ -1160,7 +1216,7 @@ func (s *Store) TogglePinChatMessage(ctx context.Context, meID, partnerID, msgID
out := s.pool.QueryRow(ctx, `
UPDATE chat_messages SET pinned_at=NULL WHERE id=$1
RETURNING id, user_id, mentor_id, sender_role, body, read_at, created_at, reply_to,
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at`, msgID)
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at, edited_at`, msgID)
return scanMessage(out)
}
var n int
@@ -1188,7 +1244,7 @@ func (s *Store) TogglePinChatMessage(ctx context.Context, meID, partnerID, msgID
out := s.pool.QueryRow(ctx, `
UPDATE chat_messages SET pinned_at=now() WHERE id=$1
RETURNING id, user_id, mentor_id, sender_role, body, read_at, created_at, reply_to,
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at`, msgID)
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at, edited_at`, msgID)
return scanMessage(out)
}
@@ -1196,7 +1252,7 @@ func (s *Store) TogglePinChatMessage(ctx context.Context, meID, partnerID, msgID
func (s *Store) ListPinnedChatMessages(ctx context.Context, userID, mentorID int64) ([]models.ChatMessage, error) {
rows, err := s.pool.Query(ctx, `
SELECT id, user_id, mentor_id, sender_role, body, read_at, created_at, reply_to,
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at, edited_at
FROM chat_messages
WHERE pinned_at IS NOT NULL
AND ((user_id=$1 AND mentor_id=$2) OR (user_id=$2 AND mentor_id=$1))
@@ -1222,7 +1278,7 @@ func (s *Store) ListPinnedChatMessages(ctx context.Context, userID, mentorID int
func (s *Store) ListChatMessages(ctx context.Context, userID, mentorID, before, limit int64) ([]models.ChatMessage, error) {
rows, err := s.pool.Query(ctx, `
SELECT id, user_id, mentor_id, sender_role, body, read_at, created_at, reply_to,
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at, edited_at
FROM chat_messages
WHERE ((user_id=$1 AND mentor_id=$2) OR (user_id=$2 AND mentor_id=$1))
AND ($3 = 0 OR id < $3)
@@ -1270,7 +1326,7 @@ func (s *Store) ListChatMessagesAround(ctx context.Context, userID, partnerID, a
older, err := s.pool.Query(ctx, `
SELECT id, user_id, mentor_id, sender_role, body, read_at, created_at, reply_to,
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at, edited_at
FROM chat_messages
WHERE ((user_id=$1 AND mentor_id=$2) OR (user_id=$2 AND mentor_id=$1))
AND id <= $3
@@ -1302,7 +1358,7 @@ func (s *Store) ListChatMessagesAround(ctx context.Context, userID, partnerID, a
newer, err := s.pool.Query(ctx, `
SELECT id, user_id, mentor_id, sender_role, body, read_at, created_at, reply_to,
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at
attachment_type, attachment_url, attachment_name, attachment_size, pinned_at, edited_at
FROM chat_messages
WHERE ((user_id=$1 AND mentor_id=$2) OR (user_id=$2 AND mentor_id=$1))
AND id > $3
@@ -1345,7 +1401,7 @@ func scanMessage(row messageScanner) (*models.ChatMessage, error) {
var attSize *int64
if err := row.Scan(
&m.ID, &m.UserID, &m.MentorID, &m.SenderRole, &m.Body, &m.ReadAt, &m.CreatedAt, &m.ReplyTo,
&attType, &attURL, &attName, &attSize, &m.PinnedAt,
&attType, &attURL, &attName, &attSize, &m.PinnedAt, &m.EditedAt,
); err != nil {
return nil, err
}
@@ -1372,11 +1428,20 @@ func derefInt(p *int64) int64 {
return *p
}
func (s *Store) MarkChatRead(ctx context.Context, userID, mentorID int64) error {
_, err := s.pool.Exec(ctx, `
UPDATE chat_messages SET read_at=now() WHERE (user_id=$1 AND mentor_id=$2) OR (user_id=$2 AND mentor_id=$1)`,
userID, mentorID)
return err
// MarkChatRead stamps messages the other person sent. Opening the thread must not
// mark my own messages as seen.
func (s *Store) MarkChatRead(ctx context.Context, meID, partnerID int64, meRole models.Role) (int64, error) {
tag, err := s.pool.Exec(ctx, `
UPDATE chat_messages
SET read_at=now()
WHERE read_at IS NULL
AND sender_role <> $3
AND ((user_id=$1 AND mentor_id=$2) OR (user_id=$2 AND mentor_id=$1))`,
meID, partnerID, meRole.String())
if err != nil {
return 0, err
}
return tag.RowsAffected(), nil
}
// MessageInConversation reports whether a message belongs to a given pair.
@@ -1743,7 +1808,7 @@ func (s *Store) AllActiveUserIDs(ctx context.Context) ([]int64, error) {
func (s *Store) Stats(ctx context.Context) (map[string]any, error) {
var users, lessons, questions, events, completions int64
if err := s.pool.QueryRow(ctx, `SELECT count(*) FROM users`).Scan(&users); err != nil {
if err := s.pool.QueryRow(ctx, `SELECT count(*) FROM users WHERE role='student' AND is_active`).Scan(&users); err != nil {
return nil, err
}
if err := s.pool.QueryRow(ctx, `SELECT count(*) FROM lessons`).Scan(&lessons); err != nil {