feat: textbooks — модуль учебников + чтение как ДЗ (3 фазы)

Фаза 1 — структура и каталог:
  - frontend/textbooks/chemistry_9.html (Шиманович, 60 §) + physics_9.html (Исаченкова, 38 §)
  - frontend/textbooks.html — каталог в стиле LearnSpace (карточки с обложками)
  - Маршруты: /textbooks (каталог), /textbook/<slug> (полноэкранный учебник)
  - Сайдбар: пункт «Учебники» (book-open-text)
  - Feature flag feature_textbooks_enabled, hideDisabledFeatures map

Фаза 2 — прогресс в localStorage + UI чтения:
  - frontend/js/textbook-tracker.js — инжектится в каждый учебник:
    - «← Учебники» overlay-кнопка (top-left, semi-transparent)
    - «Прочитано» чекбокс рядом с каждым §-заголовком
    - Зелёный dot на pill уже прочитанных параграфов
    - Авто-открытие последнего параграфа при возврате
  - Каталог показывает прогресс-бар «X из Y прочитано» + кнопку «Продолжить»

Фаза 3 — серверный прогресс + назначение чтения как ДЗ:
  - Таблица textbooks (slug, subject, grade, title, author, color, ...)
  - Таблица textbook_progress (user_id, textbook_id, JSON read[], last_para)
  - Колонки assignments.textbook_id + textbook_paragraphs
  - API: GET /api/textbooks (с прогрессом), GET /:slug, POST /:slug/progress,
    GET /:slug/class-progress (учитель)
  - tracker.js синхронизирует прогресс через POST /progress (если залогинен)
  - На каталоге у учителей кнопка «Назначить чтение» — модалка с выбором
    классов + параграфы («1-5» или «1,3,5») + deadline
  - bulkCreateAssignment расширен: принимает textbook_slug, резолвит в id

Миграция 004 идемпотентная; сиды двух учебников включены.

backend/src/controllers/assignmentController.js

@@ -595,7 +595,8 @@ function deleteTemplate(req, res) {
 
 /* ── POST /api/assignments/bulk ── assign to multiple classes at once ───── */
 function bulkCreateAssignment(req, res) {
-  const { class_ids, title, mode = 'exam', count = 25, topic_id, deadline, test_id, file_id, is_homework = 0 } = req.body;
+  const { class_ids, title, mode = 'exam', count = 25, topic_id, deadline, test_id, file_id,
+          is_homework = 0, textbook_slug, textbook_paragraphs } = req.body;
   let { subject_slug } = req.body;
 
   if (!Array.isArray(class_ids) || !class_ids.length)
@@ -608,6 +609,16 @@ function bulkCreateAssignment(req, res) {
     if (!t) return res.status(400).json({ error: 'Test not found' });
     subject_slug = t.subject_slug;
   }
+
+  // Textbook: resolve slug → id, derive subject from textbook
+  let textbook_id = null;
+  if (textbook_slug) {
+    const tb = db.prepare('SELECT id, subject FROM textbooks WHERE slug=? AND is_active=1').get(textbook_slug);
+    if (!tb) return res.status(400).json({ error: 'Учебник не найден' });
+    textbook_id = tb.id;
+    if (!subject_slug) subject_slug = tb.subject;
+  }
+
   if (!subject_slug && !is_homework) return res.status(400).json({ error: 'subject_slug required' });
   if (!subject_slug) subject_slug = 'other';
 
@@ -619,9 +630,9 @@ function bulkCreateAssignment(req, res) {
       if (req.user.role !== 'admin' && cls.teacher_id !== req.user.id) continue;
 
       const r = db.prepare(`
-        INSERT INTO assignments (class_id, title, subject_slug, mode, count, topic_id, deadline, created_by, test_id, file_id, is_homework)
-        VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
-      `).run(cls.id, stripTags(title.trim()), subject_slug, mode, Number(count), topic_id || null, deadline || null, req.user.id, test_id || null, file_id || null, is_homework ? 1 : 0);
+        INSERT INTO assignments (class_id, title, subject_slug, mode, count, topic_id, deadline, created_by, test_id, file_id, is_homework, textbook_id, textbook_paragraphs)
+        VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+      `).run(cls.id, stripTags(title.trim()), subject_slug, mode, Number(count), topic_id || null, deadline || null, req.user.id, test_id || null, file_id || null, is_homework ? 1 : 0, textbook_id, textbook_paragraphs || null);
       ids.push(r.lastInsertRowid);
 
       const members = db.prepare('SELECT user_id FROM class_members WHERE class_id = ?').all(cls.id);

backend/src/db/migrations/004_textbooks.sql

@@ -0,0 +1,42 @@
+-- Feature flag for textbooks module
+INSERT OR IGNORE INTO app_settings (key, value) VALUES ('feature_textbooks_enabled', '1');
+
+-- Catalog of textbooks (admin-editable; html_path is relative to /frontend/textbooks/)
+CREATE TABLE textbooks (
+  id           INTEGER PRIMARY KEY AUTOINCREMENT,
+  slug         TEXT    UNIQUE NOT NULL,
+  subject      TEXT    NOT NULL,                -- 'chemistry', 'physics', 'math', 'biology', ...
+  grade        INTEGER NOT NULL,                -- 9, 10, 11, ...
+  title        TEXT    NOT NULL,
+  author       TEXT    NOT NULL DEFAULT '',
+  description  TEXT    NOT NULL DEFAULT '',
+  html_path    TEXT    NOT NULL,                -- relative filename: 'chemistry_9.html'
+  para_count   INTEGER NOT NULL DEFAULT 0,      -- total paragraphs (for progress %)
+  color        TEXT    NOT NULL DEFAULT 'violet',-- visual theme: 'amber','blue','violet','green',...
+  sort_order   INTEGER NOT NULL DEFAULT 0,
+  is_active    INTEGER NOT NULL DEFAULT 1,
+  created_at   TEXT    NOT NULL DEFAULT (datetime('now'))
+);
+
+-- Per-user reading progress (one row per (user, textbook))
+CREATE TABLE textbook_progress (
+  user_id          INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+  textbook_id      INTEGER NOT NULL REFERENCES textbooks(id) ON DELETE CASCADE,
+  paragraphs_read  TEXT    NOT NULL DEFAULT '[]',   -- JSON array of para keys like ["p1","p3","p7"]
+  last_para        TEXT,                            -- last opened paragraph key (e.g. 'p15')
+  last_at          TEXT    NOT NULL DEFAULT (datetime('now')),
+  PRIMARY KEY (user_id, textbook_id)
+);
+
+-- Assignment extension: link to textbook + paragraph range string ("1-5" or "1,3,5")
+ALTER TABLE assignments ADD COLUMN textbook_id INTEGER REFERENCES textbooks(id) ON DELETE SET NULL;
+ALTER TABLE assignments ADD COLUMN textbook_paragraphs TEXT;
+
+-- Seed: chemistry 9 + physics 9 (the two files we just copied)
+INSERT INTO textbooks (slug, subject, grade, title, author, description, html_path, para_count, color, sort_order) VALUES
+  ('chemistry-9', 'chemistry', 9, 'Химия — 9 класс',  'Шиманович Е. Я.',
+   'Полный курс химии за 9 класс. §1–60: строение атома, химическая связь, классы соединений, ОВР, металлы и их соединения, электролиз.',
+   'chemistry_9.html', 60, 'amber', 1),
+  ('physics-9',   'physics',   9, 'Физика — 9 класс', 'Исаченкова Л. А.',
+   'Полный курс физики за 9 класс: §1–38. Механика, кинематика, динамика, статика, законы сохранения, импульс, работа и энергия.',
+   'physics_9.html', 38, 'blue', 2);

backend/src/routes/textbooks.js

@@ -0,0 +1,109 @@
+'use strict';
+const router = require('express').Router();
+const db = require('../db/db');
+const { authMiddleware, requireRole } = require('../middleware/auth');
+
+router.use(authMiddleware);
+
+/* GET /api/textbooks — list with current user's progress */
+router.get('/', (req, res) => {
+  const rows = db.prepare(`
+    SELECT t.id, t.slug, t.subject, t.grade, t.title, t.author, t.description,
+           t.html_path, t.para_count, t.color, t.sort_order
+    FROM textbooks t
+    WHERE t.is_active = 1
+    ORDER BY t.sort_order, t.subject, t.grade
+  `).all();
+
+  const myProgress = db.prepare(`
+    SELECT textbook_id, paragraphs_read, last_para, last_at FROM textbook_progress WHERE user_id=?
+  `).all(req.user.id);
+  const progressMap = {};
+  for (const p of myProgress) {
+    let arr = [];
+    try { arr = JSON.parse(p.paragraphs_read || '[]'); } catch {}
+    progressMap[p.textbook_id] = { read: arr, last_para: p.last_para, last_at: p.last_at };
+  }
+
+  res.json({
+    textbooks: rows.map(t => ({
+      ...t,
+      progress: progressMap[t.id] || { read: [], last_para: null, last_at: null },
+    })),
+  });
+});
+
+/* GET /api/textbooks/:slug — single textbook detail */
+router.get('/:slug', (req, res) => {
+  const t = db.prepare('SELECT * FROM textbooks WHERE slug=? AND is_active=1').get(req.params.slug);
+  if (!t) return res.status(404).json({ error: 'Учебник не найден' });
+
+  const p = db.prepare('SELECT paragraphs_read, last_para, last_at FROM textbook_progress WHERE user_id=? AND textbook_id=?').get(req.user.id, t.id);
+  let read = [];
+  if (p) { try { read = JSON.parse(p.paragraphs_read || '[]'); } catch {} }
+
+  res.json({ ...t, progress: { read, last_para: p?.last_para || null, last_at: p?.last_at || null } });
+});
+
+/* POST /api/textbooks/:slug/progress — update progress
+   body: { last_para?: 'p15', mark_read?: 'p15', mark_unread?: 'p15' } */
+router.post('/:slug/progress', (req, res) => {
+  const t = db.prepare('SELECT id FROM textbooks WHERE slug=? AND is_active=1').get(req.params.slug);
+  if (!t) return res.status(404).json({ error: 'Учебник не найден' });
+
+  const { last_para, mark_read, mark_unread } = req.body || {};
+
+  // Atomic upsert
+  const existing = db.prepare('SELECT paragraphs_read FROM textbook_progress WHERE user_id=? AND textbook_id=?').get(req.user.id, t.id);
+  let arr = [];
+  if (existing) { try { arr = JSON.parse(existing.paragraphs_read || '[]'); } catch {} }
+
+  if (mark_read && typeof mark_read === 'string' && !arr.includes(mark_read)) arr.push(mark_read);
+  if (mark_unread && typeof mark_unread === 'string') arr = arr.filter(p => p !== mark_unread);
+
+  db.prepare(`
+    INSERT INTO textbook_progress (user_id, textbook_id, paragraphs_read, last_para, last_at)
+    VALUES (?, ?, ?, ?, datetime('now'))
+    ON CONFLICT(user_id, textbook_id) DO UPDATE SET
+      paragraphs_read = excluded.paragraphs_read,
+      last_para       = COALESCE(excluded.last_para, textbook_progress.last_para),
+      last_at         = excluded.last_at
+  `).run(req.user.id, t.id, JSON.stringify(arr), last_para || null);
+
+  res.json({ ok: true, read: arr });
+});
+
+/* GET /api/textbooks/:slug/class-progress — teacher view: progress of all students in class
+   query: ?class_id=N */
+router.get('/:slug/class-progress', requireRole('teacher', 'admin'), (req, res) => {
+  const t = db.prepare('SELECT id FROM textbooks WHERE slug=?').get(req.params.slug);
+  if (!t) return res.status(404).json({ error: 'Учебник не найден' });
+  const classId = Number(req.query.class_id);
+  if (!classId) return res.status(400).json({ error: 'class_id обязателен' });
+
+  if (req.user.role === 'teacher') {
+    const own = db.prepare('SELECT 1 FROM classes WHERE id=? AND teacher_id=?').get(classId, req.user.id);
+    if (!own) return res.status(403).json({ error: 'Нет доступа к классу' });
+  }
+
+  const rows = db.prepare(`
+    SELECT u.id AS user_id, u.name,
+           COALESCE(tp.paragraphs_read, '[]') AS paragraphs_read,
+           tp.last_para, tp.last_at
+    FROM class_members cm
+    JOIN users u ON u.id = cm.user_id
+    LEFT JOIN textbook_progress tp ON tp.user_id = u.id AND tp.textbook_id = ?
+    WHERE cm.class_id = ?
+    ORDER BY u.name
+  `).all(t.id, classId);
+
+  res.json({
+    students: rows.map(r => {
+      let read = [];
+      try { read = JSON.parse(r.paragraphs_read); } catch {}
+      return { user_id: r.user_id, name: r.name, read_count: read.length, last_para: r.last_para, last_at: r.last_at };
+    }),
+  });
+});
+
+module.exports = router;

backend/src/server.js

@@ -51,6 +51,7 @@ const collectionRoutes    = require('./routes/collection');
 const redBookRoutes       = require('./routes/red-book');
 const parentRoutes        = require('./routes/parent');
 const exam9Routes         = require('./routes/exam9');
+const textbookRoutes      = require('./routes/textbooks');
 
 const { requestId, errorHandler } = require('./middleware/errorHandler');
 
@@ -168,6 +169,7 @@ app.use('/api/red-book',     redBookRoutes);
 app.use('/api/biochem',      require('./routes/biochem'));
 app.use('/api/parent',       parentRoutes);
 app.use('/api/exam9',        exam9Routes);
+app.use('/api/textbooks',    textbookRoutes);
 
 /* ── Public features endpoint (merges global + per-class for authenticated students) ── */
 const _featDb = require('./db/db');
@@ -318,6 +320,23 @@ app.use((req, res, next) => {
   next();
 });
 
+// Clean URL for textbooks: /textbook/<slug> → frontend/textbooks/<html_path>
+const _textbookDb = require('./db/db');
+const _stmtTextbookPath = _textbookDb.prepare('SELECT html_path FROM textbooks WHERE slug=? AND is_active=1');
+app.get('/textbook/:slug', (req, res, next) => {
+  const row = _stmtTextbookPath.get(req.params.slug);
+  if (!row) return next();
+  const filePath = path.join(frontendDir, 'textbooks', row.html_path);
+  if (!isProd) res.setHeader('Cache-Control', 'no-store');
+  res.sendFile(filePath, err => { if (err) next(); });
+});
+
+// Catalog: /textbooks → frontend/textbooks.html (explicit to avoid conflict with /textbooks/ directory)
+app.get('/textbooks', (_req, res) => {
+  if (!isProd) res.setHeader('Cache-Control', 'no-store');
+  res.sendFile(path.join(frontendDir, 'textbooks.html'));
+});
+
 // Serve HTML files without extension  (/dashboard → dashboard.html)
 // In dev: disable cache so edits are always picked up immediately
 const htmlCacheOpts = isProd ? { extensions: ['html'] } : {