feat: Lightning Network integration for tool usage (#610)

Co-authored-by: Kimi Agent <kimi@timmy.local>
Co-committed-by: Kimi Agent <kimi@timmy.local>

tests/unit/test_lightning.py

@@ -0,0 +1,109 @@
+"""Unit tests for the lightning package (factory + ledger)."""
+
+from __future__ import annotations
+
+import pytest
+
+from lightning.factory import Invoice, MockBackend, get_backend
+from lightning.ledger import (
+    TxStatus,
+    TxType,
+    clear,
+    create_invoice_entry,
+    get_balance,
+    get_transactions,
+    mark_settled,
+)
+
+
+@pytest.fixture(autouse=True)
+def _clean_ledger():
+    """Reset the in-memory ledger between tests."""
+    clear()
+    yield
+    clear()
+
+
+# ── Factory tests ────────────────────────────────────────────────────
+
+
+class TestMockBackend:
+    def test_create_invoice_returns_invoice(self):
+        backend = MockBackend()
+        inv = backend.create_invoice(100, "test memo")
+        assert isinstance(inv, Invoice)
+        assert inv.amount_sats == 100
+        assert inv.memo == "test memo"
+        assert len(inv.payment_hash) == 64  # SHA-256 hex
+        assert inv.payment_request.startswith("lnbc")
+
+    def test_invoices_have_unique_hashes(self):
+        backend = MockBackend()
+        a = backend.create_invoice(10)
+        b = backend.create_invoice(10)
+        assert a.payment_hash != b.payment_hash
+
+
+class TestGetBackend:
+    def test_returns_mock_backend(self):
+        backend = get_backend()
+        assert isinstance(backend, MockBackend)
+
+
+# ── Ledger tests ─────────────────────────────────────────────────────
+
+
+class TestLedger:
+    def test_create_invoice_entry(self):
+        entry = create_invoice_entry(
+            payment_hash="abc123",
+            amount_sats=500,
+            memo="test",
+            source="unit_test",
+        )
+        assert entry.tx_type == TxType.incoming
+        assert entry.status == TxStatus.pending
+        assert entry.amount_sats == 500
+
+    def test_mark_settled(self):
+        create_invoice_entry(payment_hash="hash1", amount_sats=100)
+        result = mark_settled("hash1", preimage="secret")
+        assert result is not None
+        assert result.status == TxStatus.settled
+        assert result.preimage == "secret"
+        assert result.settled_at != ""
+
+    def test_mark_settled_unknown_hash(self):
+        assert mark_settled("nonexistent") is None
+
+    def test_get_balance_empty(self):
+        bal = get_balance()
+        assert bal["net_sats"] == 0
+        assert bal["available_sats"] == 0
+
+    def test_get_balance_with_settled(self):
+        create_invoice_entry(payment_hash="h1", amount_sats=1000)
+        mark_settled("h1")
+        bal = get_balance()
+        assert bal["incoming_total_sats"] == 1000
+        assert bal["net_sats"] == 1000
+        assert bal["available_sats"] == 1000
+
+    def test_get_balance_pending_not_counted(self):
+        create_invoice_entry(payment_hash="h2", amount_sats=500)
+        bal = get_balance()
+        assert bal["incoming_total_sats"] == 0
+        assert bal["pending_incoming_sats"] == 500
+
+    def test_get_transactions_returns_entries(self):
+        create_invoice_entry(payment_hash="t1", amount_sats=10)
+        create_invoice_entry(payment_hash="t2", amount_sats=20)
+        txs = get_transactions()
+        assert len(txs) == 2
+
+    def test_get_transactions_filter_by_status(self):
+        create_invoice_entry(payment_hash="f1", amount_sats=10)
+        create_invoice_entry(payment_hash="f2", amount_sats=20)
+        mark_settled("f1")
+        assert len(get_transactions(status="settled")) == 1
+        assert len(get_transactions(status="pending")) == 1