From 132d51777a66dcd35aee39397f49b09ca29885cc Mon Sep 17 00:00:00 2001
From: Pablo Martin <pablo.martin@superhog.com>
Date: Mon, 26 May 2025 14:50:21 +0200
Subject: [PATCH] add currency pair class

---
 tests/tests_unit/test_currency_pair.py | 35 ++++++++++++++++++++++++++
 xexe/currency_pair.py                  | 19 ++++++++++++++
 2 files changed, 54 insertions(+)
 create mode 100644 tests/tests_unit/test_currency_pair.py
 create mode 100644 xexe/currency_pair.py

diff --git a/tests/tests_unit/test_currency_pair.py b/tests/tests_unit/test_currency_pair.py
new file mode 100644
index 0000000..93aeccc
--- /dev/null
+++ b/tests/tests_unit/test_currency_pair.py
@@ -0,0 +1,35 @@
+from money.currency import Currency
+
+from xexe.currency_pair import CurrencyPair
+
+
+def test_create_currency_pair_normal_works_fine():
+
+    a_pair: CurrencyPair = CurrencyPair(
+        from_currency=Currency["USD"], to_currency=Currency["EUR"]
+    )
+
+    assert (a_pair.from_currency == "USD", a_pair.to_currency == "EUR")
+
+
+def test_create_currency_pair_with_same_currency_works():
+    same_curr_pair: CurrencyPair = CurrencyPair(
+        from_currency=Currency["USD"], to_currency=Currency["USD"]
+    )
+
+    assert (same_curr_pair.from_currency == "USD", same_curr_pair.to_currency == "USD")
+
+
+def test_reverse_currency_works_fine():
+
+    a_pair: CurrencyPair = CurrencyPair(
+        from_currency=Currency["USD"], to_currency=Currency["EUR"]
+    )
+
+    reverse_pair: CurrencyPair = a_pair.get_reverse_pair()
+
+    assert (
+        isinstance(reverse_pair, CurrencyPair),
+        reverse_pair.from_currency == "EUR",
+        reverse_pair.to_currency == "USD",
+    )
diff --git a/xexe/currency_pair.py b/xexe/currency_pair.py
new file mode 100644
index 0000000..c2012d5
--- /dev/null
+++ b/xexe/currency_pair.py
@@ -0,0 +1,19 @@
+from money.currency import Currency
+
+
+class CurrencyPair:
+    """Two currencies with directionality (from->to)."""
+
+    def __init__(
+        self, from_currency: Currency, to_currency: Currency
+    ) -> "CurrencyPair":
+        self.from_currency = from_currency
+        self.to_currency = to_currency
+
+    def __str__(self):
+        return str(self.from_currency) + str(self.to_currency)
+
+    def get_reverse_pair(self) -> "CurrencyPair":
+        return CurrencyPair(
+            from_currency=self.to_currency, to_currency=self.from_currency
+        )