feat: database layer with better-sqlite3, full schema and query functions

Implements Task 4 (TDD): wrote failing tests first, then the full SQLite database layer covering profiles, magic tokens, sessions, user progress, mnemonics, and letter stats. All 14 tests pass. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-04-30 00:34:59 +00:00
parent cf2081f643
commit 9b31119c7a
4 changed files with 397 additions and 1 deletions
@@ -0,0 +1,253 @@
+'use strict'
+const Database = require('better-sqlite3')
+const path = require('path')
+
+let db
+
+function initDb(dbPath) {
+  const resolvedPath = dbPath || path.join(__dirname, '../data/morsequest.db')
+  const instance = new Database(resolvedPath)
+  instance.pragma('journal_mode = WAL')
+  instance.pragma('foreign_keys = ON')
+
+  instance.exec(`
+    CREATE TABLE IF NOT EXISTS profiles (
+      id           INTEGER PRIMARY KEY AUTOINCREMENT,
+      email        TEXT UNIQUE NOT NULL,
+      display_name TEXT,
+      created_at   INTEGER NOT NULL,
+      last_seen    INTEGER NOT NULL
+    );
+    CREATE TABLE IF NOT EXISTS magic_tokens (
+      token       TEXT PRIMARY KEY,
+      profile_id  INTEGER NOT NULL,
+      expires_at  INTEGER NOT NULL,
+      used        INTEGER NOT NULL DEFAULT 0
+    );
+    CREATE TABLE IF NOT EXISTS sessions (
+      token       TEXT PRIMARY KEY,
+      profile_id  INTEGER NOT NULL,
+      created_at  INTEGER NOT NULL,
+      last_seen   INTEGER NOT NULL
+    );
+    CREATE TABLE IF NOT EXISTS user_progress (
+      profile_id     INTEGER PRIMARY KEY,
+      level          INTEGER NOT NULL DEFAULT 1,
+      score          INTEGER NOT NULL DEFAULT 0,
+      streak         INTEGER NOT NULL DEFAULT 0,
+      best_streak    INTEGER NOT NULL DEFAULT 0,
+      total_correct  INTEGER NOT NULL DEFAULT 0,
+      total_attempts INTEGER NOT NULL DEFAULT 0,
+      last_session_at INTEGER,
+      updated_at     INTEGER NOT NULL
+    );
+    CREATE TABLE IF NOT EXISTS user_mnemonics (
+      profile_id INTEGER NOT NULL,
+      letter     TEXT NOT NULL,
+      phrase     TEXT NOT NULL,
+      created_at INTEGER NOT NULL,
+      PRIMARY KEY (profile_id, letter)
+    );
+    CREATE TABLE IF NOT EXISTS letter_stats (
+      profile_id INTEGER NOT NULL,
+      letter     TEXT NOT NULL,
+      correct    INTEGER NOT NULL DEFAULT 0,
+      attempts   INTEGER NOT NULL DEFAULT 0,
+      updated_at INTEGER NOT NULL,
+      PRIMARY KEY (profile_id, letter)
+    );
+  `)
+
+  db = instance
+
+  return {
+    _db: instance,
+    createProfile,
+    findProfileByEmail,
+    findProfileById,
+    updateProfileSeen,
+    createMagicToken,
+    useMagicToken,
+    createSession,
+    getSession,
+    deleteSession,
+    getOrCreateProgress,
+    updateLevel,
+    recordAnswer,
+    getMnemonics,
+    saveMnemonic,
+    getLetterStats,
+    getAdminUsers,
+    getAdminStats,
+  }
+}
+
+function createProfile(email, displayName) {
+  const now = Date.now()
+  const stmt = db.prepare(
+    'INSERT INTO profiles (email, display_name, created_at, last_seen) VALUES (?,?,?,?) RETURNING *'
+  )
+  return stmt.get(email, displayName || null, now, now)
+}
+
+function findProfileByEmail(email) {
+  return db.prepare('SELECT * FROM profiles WHERE email = ?').get(email) ?? null
+}
+
+function findProfileById(id) {
+  return db.prepare('SELECT * FROM profiles WHERE id = ?').get(id) ?? null
+}
+
+function updateProfileSeen(id) {
+  db.prepare('UPDATE profiles SET last_seen = ? WHERE id = ?').run(Date.now(), id)
+}
+
+function createMagicToken(token, profileId, expiresAt) {
+  db.prepare('INSERT INTO magic_tokens (token, profile_id, expires_at) VALUES (?,?,?)').run(
+    token, profileId, expiresAt
+  )
+}
+
+function useMagicToken(token) {
+  const row = db
+    .prepare('SELECT * FROM magic_tokens WHERE token = ? AND used = 0 AND expires_at > ?')
+    .get(token, Date.now())
+  if (!row) return null
+  db.prepare('UPDATE magic_tokens SET used = 1 WHERE token = ?').run(token)
+  return row.profile_id
+}
+
+function createSession(token, profileId) {
+  const now = Date.now()
+  db.prepare(
+    'INSERT INTO sessions (token, profile_id, created_at, last_seen) VALUES (?,?,?,?)'
+  ).run(token, profileId, now, now)
+}
+
+function getSession(token) {
+  const row = db.prepare('SELECT * FROM sessions WHERE token = ?').get(token)
+  if (!row) return null
+  db.prepare('UPDATE sessions SET last_seen = ? WHERE token = ?').run(Date.now(), token)
+  return row
+}
+
+function deleteSession(token) {
+  db.prepare('DELETE FROM sessions WHERE token = ?').run(token)
+}
+
+function getOrCreateProgress(profileId) {
+  const existing = db.prepare('SELECT * FROM user_progress WHERE profile_id = ?').get(profileId)
+  if (existing) return existing
+  const now = Date.now()
+  db.prepare(
+    `INSERT INTO user_progress (profile_id, level, score, streak, best_streak,
+     total_correct, total_attempts, updated_at) VALUES (?,1,0,0,0,0,0,?)`
+  ).run(profileId, now)
+  return db.prepare('SELECT * FROM user_progress WHERE profile_id = ?').get(profileId)
+}
+
+function updateLevel(profileId, level) {
+  db.prepare('UPDATE user_progress SET level = ?, updated_at = ? WHERE profile_id = ?').run(
+    level, Date.now(), profileId
+  )
+}
+
+function recordAnswer(profileId, letter, correct) {
+  const progress = getOrCreateProgress(profileId)
+  const now = Date.now()
+  const isFirstToday = !progress.last_session_at ||
+    new Date(progress.last_session_at).toDateString() !== new Date(now).toDateString()
+
+  const base = progress.level * 10
+  const newStreak = correct ? progress.streak + 1 : 0
+  const streakMult = newStreak >= 10 ? 2 : 1
+  const dailyMult = isFirstToday && correct ? 1.25 : 1
+  const points = correct ? Math.floor(base * streakMult * dailyMult) : 0
+  const newBestStreak = Math.max(progress.best_streak, newStreak)
+
+  db.prepare(
+    `UPDATE user_progress SET
+       score = score + ?,
+       streak = ?,
+       best_streak = ?,
+       total_correct = total_correct + ?,
+       total_attempts = total_attempts + 1,
+       last_session_at = ?,
+       updated_at = ?
+     WHERE profile_id = ?`
+  ).run(points, newStreak, newBestStreak, correct ? 1 : 0, now, now, profileId)
+
+  // Update letter stats
+  const existing = db
+    .prepare('SELECT * FROM letter_stats WHERE profile_id = ? AND letter = ?')
+    .get(profileId, letter)
+  if (existing) {
+    db.prepare(
+      'UPDATE letter_stats SET correct = correct + ?, attempts = attempts + 1, updated_at = ? WHERE profile_id = ? AND letter = ?'
+    ).run(correct ? 1 : 0, now, profileId, letter)
+  } else {
+    db.prepare(
+      'INSERT INTO letter_stats (profile_id, letter, correct, attempts, updated_at) VALUES (?,?,?,1,?)'
+    ).run(profileId, letter, correct ? 1 : 0, now)
+  }
+
+  return db.prepare('SELECT * FROM user_progress WHERE profile_id = ?').get(profileId)
+}
+
+function getMnemonics(profileId) {
+  const rows = db
+    .prepare('SELECT letter, phrase FROM user_mnemonics WHERE profile_id = ?')
+    .all(profileId)
+  return Object.fromEntries(rows.map(r => [r.letter, r.phrase]))
+}
+
+function saveMnemonic(profileId, letter, phrase) {
+  const now = Date.now()
+  const upperLetter = letter.toUpperCase()
+  const existing = db.prepare(
+    'SELECT 1 FROM user_mnemonics WHERE profile_id = ? AND letter = ?'
+  ).get(profileId, upperLetter)
+
+  if (existing) {
+    db.prepare('UPDATE user_mnemonics SET phrase = ? WHERE profile_id = ? AND letter = ?')
+      .run(phrase, profileId, upperLetter)
+  } else {
+    db.prepare(
+      'INSERT INTO user_mnemonics (profile_id, letter, phrase, created_at) VALUES (?,?,?,?)'
+    ).run(profileId, upperLetter, phrase, now)
+    // Award 50 points for first mnemonic save — ensure progress row exists first
+    getOrCreateProgress(profileId)
+    db.prepare('UPDATE user_progress SET score = score + 50, updated_at = ? WHERE profile_id = ?')
+      .run(now, profileId)
+  }
+}
+
+function getLetterStats(profileId) {
+  const rows = db
+    .prepare('SELECT letter, correct, attempts FROM letter_stats WHERE profile_id = ?')
+    .all(profileId)
+  return Object.fromEntries(rows.map(r => [r.letter, { correct: r.correct, attempts: r.attempts }]))
+}
+
+function getAdminUsers() {
+  return db.prepare(`
+    SELECT p.id, p.email, p.display_name, p.created_at, p.last_seen,
+           pr.level, pr.score, pr.streak, pr.best_streak,
+           pr.total_correct, pr.total_attempts
+    FROM profiles p
+    LEFT JOIN user_progress pr ON pr.profile_id = p.id
+    ORDER BY p.created_at DESC
+  `).all()
+}
+
+function getAdminStats() {
+  const totalUsers = db.prepare('SELECT COUNT(*) as c FROM profiles').get().c
+  const avgScore = db.prepare('SELECT AVG(score) as a FROM user_progress').get().a || 0
+  const mostMissed = db.prepare(`
+    SELECT letter, SUM(attempts - correct) as misses
+    FROM letter_stats GROUP BY letter ORDER BY misses DESC LIMIT 5
+  `).all()
+  return { totalUsers, avgScore: Math.round(avgScore), mostMissed }
+}
+
+module.exports = { initDb }