# Fee Calculation Spec — Tuesday Practices

## Data Source

- Google Sheet: `1E2e_gT_K5AwSRCDLDTa2UetZTkHmBOcz0kFbBUNUNBA`
- Sheet: first sheet only (Tuesday practices, 20:30–22:00)
- Public export URL (CSV): `https://docs.google.com/spreadsheets/d/1E2e_gT_K5AwSRCDLDTa2UetZTkHmBOcz0kFbBUNUNBA/export?format=csv`

## Sheet Structure

| Row | Content |
| --- | --- |
| 1 | Header: title in col A, dates in cols D+ (format `M/D/YYYY`) |
| 2 | Venue per date (irrelevant for pricing) |
| 3 | Total attendees per date |
| 4+ | Member rows: Name (col A), Tier (col B), Total (col C), attendance TRUE/FALSE (cols D+) |

Member rows end when the Name column is empty.

## Tiers

| Code | Meaning | Pays from this sheet? |
| --- | --- | --- |
| A | Adult | Yes |
| J | Junior | No (paid via separate attendance sheet) |
| X | Exempt | No |

## Fee Rules (Adults only)

Fees are calculated per calendar month based on the number of attended practices in that month.

| Practices in month | Fee |
| --- | --- |
| 0 | 0 CZK |
| 1 | 200 CZK |
| 2 or more | 750 CZK |

## Payment Matching

### Bank Account

- Fio banka transparent account: `2800359168/2010`
- Owner: Nathan Heilmann
- Public view: `https://ib.fio.cz/ib/transparent?a=2800359168`

### Data Access

- **Without API token**: scrape the public transparent account HTML page
- **With API token**: Fio REST API at `https://fioapi.fio.cz/v1/rest/periods/{token}/{from}/{to}/transactions.json`
  - Token is generated in Fio internetbanking (Settings → API)
  - Rate limit: 1 request per 30 seconds per token
  - Available fields: date, amount, currency, sender account, sender name, VS, SS, KS, user identification, message, type, and more

### Matching Approach

Payments are matched to members using best-effort heuristics, with uncertain matches flagged for manual review.

1. **Name matching**: Normalize (strip diacritics, lowercase) sender name and message text, compare against member names and nicknames
2. **Month parsing**: Extract Czech month names (leden, únor, ...) and numeric patterns (01/26, 1/2026) from the message
3. **Amount validation**: Check if amount aligns with expected fees (200, 750, or multiples)
4. **Multi-person splitting**: When a message references multiple members, split the payment across them

### Advance Payments

If a payment references a month with no attendance data yet, it is tracked as **credit** on the member's account. The credit is applied once that month's attendance is recorded.

## PII Constraint

No member names or personal data are committed to git. All data is fetched at runtime from the Google Sheet and bank account.