# Agent Instructions — Dolibarr / GoCardless / Shine Reconciliation

## Project Goal

Reconcile invoices and payments across three financial systems:
- **Dolibarr** — Invoice management (via REST API)
- **GoCardless** — Direct debit payments (via CSV export)
- **Shine** — Bank account (via CSV export)

## Design Principles

1. **Manual operation** — CSV-based, no background processes, no API integrations with payment providers
2. **Standalone** — No coupling to `console.cyanet.fr` or other projects
3. **Read-only by default** — `--fix` mode is opt-in and only affects invoices flagged `GC_PAID_DOLIBARR_OPEN`
4. **Audit trail** — CSV exports serve as snapshots; output CSVs written to `tmp/`

## Architecture

```
bin/reconcile                          # CLI entry point
lib/
  boot.rb                              # Dependency loader
  dolibarr/client.rb                   # HTTP client (HTTParty)
  reconciliation/
    dolibarr_fetcher.rb                # Fetch invoices + customer names
    gocardless_parser.rb               # Parse payments CSV
    gocardless_payouts_parser.rb       # Parse payouts CSV (fees)
    shine_parser.rb                    # Parse Shine bank CSV
    engine.rb                          # 3-pass matching logic
    reporter.rb                        # Terminal report + CSV export
    fixer.rb                           # Apply --fix mode
```

## Data Flow

```
┌─────────────┐     ┌──────────────┐     ┌─────────────┐
│  GoCardless │     │   Dolibarr   │     │    Shine    │
│   payments  │     │   invoices   │     │  transactions│
│     CSV     │     │     API      │     │     CSV     │
└──────┬──────┘     └──────┬───────┘     └──────┬──────┘
       │                   │                    │
       ▼                   ▼                    ▼
┌─────────────────────────────────────────────────────────┐
│                      Engine                             │
│  Pass 1: GC payments ↔ Dolibarr invoices                │
│  Pass 2: Open Dolibarr invoice audit                    │
│  Pass 3: GC payouts ↔ Shine bank credits                │
└─────────────────────────────────────────────────────────┘
                           │
                           ▼
              ┌────────────────────────┐
              │  Reporter + Fixer      │
              │  Terminal report       │
              │  CSV export to tmp/    │
              │  Optional --fix        │
              └────────────────────────┘
```

## Matching Logic

### Pass 1 — GC ↔ Dolibarr

| Match Type | Criteria |
|------------|----------|
| **Strong** | `payment.description == invoice.ref` (case-insensitive) |
| **Soft**   | Same amount + customer name + date within ±7 days |

### Pass 2 — Open Invoice Audit

All open Dolibarr invoices with no GC match → `DOLIBARR_OPEN_NO_GC`

### Pass 3 — GC Payouts ↔ Shine

| Match Type | Criteria |
|------------|----------|
| **Strong** | Payout reference found in Shine `Libellé` |
| **Fallback** | Exact net amount + date within ±2 days |

## Key Files to Modify

| Task | File |
|------|------|
| Add new flag | `lib/reconciliation/engine.rb` (constants + Match struct) |
| Change matching logic | `lib/reconciliation/engine.rb` (pass1/2/3 methods) |
| Add parser field | `lib/reconciliation/*_parser.rb` (Payment/Transaction/Invoice struct) |
| Change report output | `lib/reconciliation/reporter.rb` (print_summary, write_csv) |
| Add CLI option | `bin/reconcile` (OptionParser + wiring) |
| Dolibarr API calls | `lib/dolibarr/client.rb`, `lib/reconciliation/dolibarr_fetcher.rb` |

## Coding Conventions

- **Ruby 3.x** — Use `frozen_string_literal: true`
- **No external dependencies** — Only stdlib + HTTParty (already in Gemfile)
- **Amounts in cents** — Always use integers to avoid float precision issues
- **Date tolerance** — Use `DATE_TOLERANCE` / `PAYOUT_DATE_TOLERANCE` constants (configurable via ENV)
- **Name normalization** — Strip accents, lowercase, sort words for comparison

## Testing Checklist

Before committing changes:

```bash
# Syntax check
ruby -c lib/reconciliation/*.rb
ruby -c bin/reconcile

# Run reconciliation (dry run)
ruby bin/reconcile --from 2026-01-01 --to 2026-01-31 \
  --gc gocardless/*.csv --gc-payouts gocardless/*.csv \
  --shine shine/*/*.csv

# Verify CSV output
cat tmp/reconciliation_*.csv
cat tmp/payouts_fees_*.csv
```

## Common Patterns

### Adding a new flag

```ruby
# 1. Define constant in Engine
NEW_FLAG = :new_flag

# 2. Add to Match struct
Match = Struct.new(
  :flag, :invoice, :payment, :match_type, :partial, :retry_group,
  :new_field,  # if needed
  keyword_init: true
)

# 3. Set flag in matching logic
results << Match.new(flag: NEW_FLAG, ...)

# 4. Handle in reporter
r[:new_flag_matches].each do |m|
  puts "  #{m.invoice.ref}"
end
```

### Adding a new parser field

```ruby
# 1. Add to struct
Payment = Struct.new(
  :id, :charge_date, :amount_cents, :new_field,
  keyword_init: true
)

# 2. Parse from CSV
Payment.new(
  id: row["id"].to_s.strip,
  new_field: row["new_column"].to_s.strip,
  ...
)

# 3. Use in engine/reporter
```

## Gotchas

1. **Dolibarr `status=1`** — Returns all non-draft invoices (open + paid + cancelled). Filter by `statut` field in response.
2. **Shine CSV format** — Semicolon separator, French decimal (`51,10`), Windows CRLF
3. **GoCardless fees** — Payout net amount < sum of payments (fee deducted). This is normal.
4. **Credit notes** — Negative `total_ttc` invoices are excluded from reconciliation
5. **Supplier invoices** — Separate API endpoint (`/supplierinvoices`), not handled

## Environment Variables

| Variable | Default | Purpose |
|----------|---------|---------|
| `DOLIBARR_URL` | — | Dolibarr API base URL |
| `DOLIBARR_API_KEY` | — | API authentication |
| `DOLIBARR_GC_PAYMENT_ID` | — | Payment method ID for `--fix` |
| `DOLIBARR_BANK_ACCOUNT_ID` | `1` | Bank account ID for `--fix` |
| `RECONCILIATION_DATE_TOLERANCE` | `7` | Days for soft date matching |
| `RECONCILIATION_PAYOUT_TOLERANCE` | `2` | Days for payout date matching |

## Related Files

- `docs/reconciliation_plan.md` — Original design document
- `docs/dolibarr.json` — Dolibarr API spec
- `.env.example` — Environment variable template