Better logic on fund splitting

bot.py

@@ -45,9 +45,11 @@ def setup_logging(log_file: str) -> None:
     )
 
 
-def available_usd(client: KrakenClient, config: Config) -> float:
+def available_usd(client: KrakenClient, config: Config, portfolio: Portfolio) -> float:
     if config.paper_trading:
-        return float(os.getenv("PAPER_BALANCE_USD", "1000"))
+        total = float(os.getenv("PAPER_BALANCE_USD", "1000"))
+        invested = sum(pos.cost_usd for pos in portfolio.all())
+        return max(0.0, total - invested)
     try:
         return client.get_usd_balance()
     except KrakenError as exc:
@@ -129,7 +131,7 @@ def run_cycle(config: Config) -> bool:
         log.info("Portfolio full — no new positions to open.")
         return bool(closed)
 
-    balance = available_usd(client, config)
+    balance = available_usd(client, config, portfolio)
     log.info("Available balance: $%.2f  |  Open slots: %d", balance, open_slots)
 
     if balance < config.min_order_usd:
@@ -146,22 +148,26 @@ def run_cycle(config: Config) -> bool:
         log.info("No opportunities matching criteria this cycle.")
         return bool(closed)
 
-    # Cap to available slots and allocate equally
-    to_buy = opportunities[:open_slots]
-    alloc_per_asset = balance / len(to_buy)
+    # Sort by 24h change descending — strongest movers get priority when funds are limited
+    opportunities.sort(key=lambda o: o.change_pct, reverse=True)
+
+    # How many can we actually afford at the minimum order size?
+    affordable = int(balance // config.min_order_usd)
+    num_to_buy = min(open_slots, affordable, len(opportunities))
+
+    if num_to_buy == 0:
+        log.info("Balance $%.2f too low for even one minimum order ($%.2f).", balance, config.min_order_usd)
+        return bool(closed)
+
+    to_buy = opportunities[:num_to_buy]
+    # Split available balance equally across the chosen assets (always >= min_order_usd)
+    alloc_per_asset = balance / num_to_buy
     log.info(
         "Buying %d asset(s) @ $%.2f each (total $%.2f)",
-        len(to_buy), alloc_per_asset, alloc_per_asset * len(to_buy),
+        num_to_buy, alloc_per_asset, alloc_per_asset * num_to_buy,
     )
 
     for opp in to_buy:
-        if alloc_per_asset < config.min_order_usd:
-            log.warning(
-                "Allocation $%.2f < minimum $%.2f — skipping %s",
-                alloc_per_asset, config.min_order_usd, opp.pair,
-            )
-            continue
-
         quantity = round(alloc_per_asset / opp.last_price, opp.lot_decimals)
 
         if opp.order_min > 0 and quantity < opp.order_min: