# Content as data

Question collections live here as YAML, imported via a single CLI.
This replaces the ad-hoc `backend/scripts/seed_phys_ct2024.js` pattern.

## Import command

```sh
cd backend
npm run import:content -- ../content/phys/ct-2024.yaml
```

## File format

```yaml
meta:
  subject: phys          # phys | math | bio | chem
  year: 2024             # exam year (integer)
  source: "ЦЭ,ЦТ 2024"  # optional label shown in import log

topics:
  kinem:                 # topic alias (see aliases below)
    - text: |
        Question text (multi-line supported, LaTeX with \( \) works)
      difficulty: 1      # 1=easy, 2=medium, 3=hard  (default: 1)
      explanation: "Solution explanation"  # optional
      options:
        - { text: "Answer A", correct: true }  # exactly ONE correct
        - { text: "Answer B" }
        - { text: "Answer C" }

  "Full topic name":     # or use full Russian name — will be found or created
    - text: "..."
      options: [...]
```

## Topic aliases (subject=phys)

| Alias    | Topic name                      |
|----------|---------------------------------|
| kinem    | Кинематика                      |
| dynam    | Динамика                        |
| cons     | Законы сохранения               |
| mol      | Молекулярная физика             |
| thermo   | Термодинамика                   |
| electro  | Электростатика                  |
| dc       | Постоянный ток                  |
| magnet   | Магнетизм                       |
| emf      | Электромагнитная индукция       |
| optics   | Оптика                          |
| quantum  | Квантовая и ядерная физика      |
| waves    | Колебания и волны               |

For other topic names, use the full Russian name as the key — the importer
looks it up in the database (case-insensitive) or creates a new topic.

## Dedup logic

Questions are skipped if the first 80 characters of their text already
exist in the database for the same subject. This matches the legacy
`seed_phys_*.js` behavior, ensuring idempotent re-runs.

## Migrating a legacy seed_*.js

1. Copy the file structure from `content/phys/ct-2024.yaml`
2. Convert each `q(T.kinem, text, opts, diff, year, expl)` call to YAML:
   - `T.kinem` → `topics: kinem:`
   - `text` → `text: |` (use literal block for multi-line)
   - `opts: [{t: "...", c: true}, ...]` → `options: [{text: "...", correct: true}, ...]`
   - `diff` → `difficulty:`
   - `expl` → `explanation:`
3. Run `npm run import:content -- ../content/<subject>/<file>.yaml`
4. Verify output shows expected `added` count
5. Keep the legacy `seed_*.js` file as backup until verified

## Collections

| File | Subject | Year | Source | Questions |
|------|---------|------|--------|-----------|
| phys/ct-2024.yaml | Физика | 2024 | ЦЭ,ЦТ 2024 | 13 (proof subset) |