# Unit 00 — Project Structure

## Goal
Scaffold all directories, `__init__` files, `requirements.txt`, and `config.yaml.example`. No logic yet — just the skeleton.

## Files to Create

### `requirements.txt`
```
Flask==3.0.0
cryptography==41.0.7
pymongo==4.6.0
requests==2.31.0
pyyaml==6.0.1
pytest==7.4.0
```
> Note: `pySim` is deferred to Unit 06 (real eSIM profile generation) due to install complexity. Unit 02 uses a mock profile.

### `config.yaml.example`
```yaml
network:
  mcc: "302"
  mnc: "720"
  plmn: "302720"
  op_key: "63bfa50ee6523365ff14c1f45f88737d"  # 16-byte hex OP key

wifi:
  ssid: "Emergency-5G"
  channel: 6
  ip: "192.168.4.1"
  subnet: "192.168.4.0/24"
  dhcp_range: "192.168.4.10,192.168.4.250"

server:
  host: "0.0.0.0"
  port: 5000
  debug: false

database:
  path: "/opt/esim-provisioning/data/subscribers.db"

rate_limiting:
  max_profiles_per_mac: 1
  window_hours: 1

core:
  type: "open5gs"           # "open5gs" | "free5gc" | "none"
  mongodb_uri: "mongodb://localhost:27017"
  database_name: "open5gs"

profile:
  carrier_name: "Ad-Hoc Network"
  profile_name: "Emergency 5G"
  apn: "internet"
```

### Directory Structure
```
esim-provisioning/
├── requirements.txt
├── config.yaml.example
├── server/
│   ├── __init__.py           (empty)
│   └── core_adapters/
│       └── __init__.py       (empty — factory added in Unit 04)
├── portal/
│   ├── css/                  (populated in Unit 06)
│   ├── js/                   (populated in Unit 06)
│   └── assets/               (empty)
├── scripts/                  (populated in Unit 07)
├── tests/
│   └── __init__.py           (empty)
├── android/                  (populated in Unit 09)
├── systemd/                  (populated in Unit 08)
├── configs/                  (populated in Unit 08)
└── plan/                     (these files — already done)
```

## Verification
```bash
python3 -m venv venv && source venv/bin/activate
pip install -r requirements.txt
# Should complete with no errors
python -c "import flask, cryptography, pymongo, yaml; print('OK')"
```