1 files changed, 48 insertions, 0 deletions
diff --git a/trade_queue.py b/trade_queue.py
new file mode 100644
index 0000000..b8c594b
--- /dev/null
+++ b/trade_queue.py
@@ -0,0 +1,48 @@
+from collections import deque
+from typing import Deque, List
+
+from trade import Trade
+
+
+class FIFOQueue:
+    """
+    Crypto trading FIFO queue.
+
+    Will track trades.
+    """
+    def __init__(self) -> None:
+        self.queue: Deque[Trade] = deque()
+
+    def add(self, amount: float, total_cost: float, date: str) -> None:
+        """
+        Add a trade to the queue.
+        """
+        trade = Trade(amount, total_cost, date)
+        self.queue.append(trade)
+
+    def remove(self, amount: float) -> List[Trade]:
+        """
+        Remove a specified amount from the queue, returning the
+        trades used to buy.
+        """
+        if amount <= 0:
+            raise ValueError("The amount to remove must be positive.")
+
+        remaining: float = amount
+        entries: List[Trade] = []
+
+        while remaining > 0:
+            if not self.queue:
+                raise ValueError(f"Insufficient assets in queue to process sale of {amount}.")
+
+            trade = self.queue[0]
+            if trade.amount > remaining:
+                trade.amount -= remaining
+                entries.append(Trade(remaining, trade.total_cost, trade.date))
+                remaining = 0
+            else:
+                remaining -= trade.amount
+                entries.append(trade)
+                self.queue.popleft()
+
+        return entries