# Baseline Seed Data Plan

This document captures the datasets that should be present in a fresh CalMiner installation and the structure required to manage them through `scripts/seed_data.py`.

## Currency Catalog

The `currency` table already exists and is seeded today via `scripts/seed_data.py`. The goal is to keep the canonical list in one place and ensure the default currency (USD) is always active.

| Code | Name                | Symbol | Notes                                    |
| ---- | ------------------- | ------ | ---------------------------------------- |
| USD  | US Dollar           | $      | Default currency (`DEFAULT_CURRENCY_CODE`) |
| EUR  | Euro                | EUR symbol |                                        |
| CLP  | Chilean Peso        | $      |                                          |
| RMB  | Chinese Yuan        | RMB symbol |                                        |
| GBP  | British Pound       | GBP symbol |                                        |
| CAD  | Canadian Dollar     | $      |                                          |
| AUD  | Australian Dollar   | $      |                                          |

Seeding behaviour:

- Upsert by ISO code; keep existing name/symbol when updated manually.
- Ensure `is_active` remains true for USD and defaults to true for new rows.
- Defer to runtime validation in `routes.currencies` for enforcing default behaviour.

## Measurement Units

UI routes (`routes/ui.py`) currently rely on the in-memory `MEASUREMENT_UNITS` list to populate dropdowns for consumption and production forms. To make this configurable and available to the API, introduce a dedicated `measurement_unit` table and seed it.

Proposed schema:

| Column        | Type           | Notes                                |
| ------------- | -------------- | ------------------------------------ |
| id            | SERIAL / BIGINT | Primary key.                         |
| code          | TEXT           | Stable slug (e.g. `tonnes`). Unique. |
| name          | TEXT           | Display label.                       |
| symbol        | TEXT           | Short symbol (nullable).             |
| unit_type     | TEXT           | Category (`mass`, `volume`, `energy`).|
| is_active     | BOOLEAN        | Default `true` for soft disabling.   |
| created_at    | TIMESTAMP      | Optional `NOW()` default.            |
| updated_at    | TIMESTAMP      | Optional `NOW()` trigger/default.    |

Initial seed set (mirrors existing UI list plus type categorisation):

| Code            | Name             | Symbol | Unit Type |
| --------------- | ---------------- | ------ | --------- |
| tonnes          | Tonnes           | t      | mass      |
| kilograms       | Kilograms        | kg     | mass      |
| pounds          | Pounds           | lb     | mass      |
| liters          | Liters           | L      | volume    |
| cubic_meters    | Cubic Meters     | m3     | volume    |
| kilowatt_hours  | Kilowatt Hours   | kWh    | energy    |

Seeding behaviour:

- Upsert rows by `code`.
- Preserve `unit_type` and `symbol` unless explicitly changed via administration tooling.
- Continue surfacing unit options to the UI by querying this table instead of the static constant.

## Default Settings

The application expects certain defaults to exist:

- **Default currency**: enforced by `routes.currencies._ensure_default_currency`; ensure seeds keep USD active.
- **Fallback measurement unit**: UI currently auto-selects the first option in the list. Once units move to the database, expose an application setting to choose a fallback (future work tracked under "Application Settings management").

## Seeding Structure Updates

To support the datasets above:

1. Extend `scripts/seed_data.py` with a `SeedDataset` registry so each dataset (currencies, units, future defaults) can declare its loader/upsert function and optional dependencies.
2. Add a `--dataset` CLI selector for targeted seeding while keeping `--all` as the default for `setup_database.py` integrations.
3. Update `scripts/setup_database.py` to:
   - Run migration ensuring `measurement_unit` table exists.
   - Execute the unit seeder after currencies when `--seed-data` is supplied.
   - Verify post-seed counts, logging which dataset was inserted/updated.
4. Adjust UI routes to load measurement units from the database and remove the hard-coded list once the table is available.

This plan aligns with the TODO item for seeding initial data and lays the groundwork for consolidating migrations around a single baseline file that introduces both the schema and seed data in an idempotent manner.