1 files changed, 145 insertions, 0 deletions
diff --git a/backend/src/pathfinder.py b/backend/src/pathfinder.py
new file mode 100644
index 0000000..80e7a44
--- /dev/null
+++ b/backend/src/pathfinder.py
@@ -0,0 +1,145 @@
+import logging
+from dataclasses import dataclass
+from tqdm import tqdm
+
+from arbitrage import Trade
+from graph import Graph
+
+logging.basicConfig(level=logging.INFO)
+logger = logging.getLogger(__name__)
+
+@dataclass
+class Ship:
+    location: int
+    cargo: int
+    max_warp_speed: float
+    max_subwarp_speed: float
+    gankers_areas: list[str]
+    player_cost: float
+    risk_cost: float
+
+
+def pathfinder(order_matches: list[Trade], graph: Graph, ship: Ship) -> list[Trade]:
+    """
+    Processes order matches by filtering and calculating net profit.
+
+    Args:
+        order_matches: List of trade opportunities.
+        graph: Navigation graph.
+        ship: Ship parameters.
+
+    Returns:
+        A list of filtered and annotated trade opportunities.
+    """
+    order_matches = filter_order_matches_not_in_graph(order_matches, graph)
+    logger.info("After filtering order matches not in graph: %d", len(order_matches))
+          
+    order_matches = filter_order_matches_same_region(order_matches, graph)
+    logger.info("After filtering order matches to same region: %d", len(order_matches))
+
+    order_matches = calculate_net_profit(order_matches, graph, ship)
+
+    order_matches = filter_order_matches_low_profit(order_matches)
+    logger.info("After filtering low profit order matches: %d", len(order_matches))
+
+    return order_matches
+
+def filter_order_matches_not_in_graph(order_matches: list[Trade], graph: Graph) -> list[Trade]:
+    """
+    Filters out order matches where either the from_station or to_station is not in the graph.
+
+    Args:
+        order_matches: List of trade opportunities.
+        graph: Navigation graph.
+
+    Returns:
+        Filtered list of trade opportunities.
+    """
+    return [
+        order_match for order_match in order_matches
+        if order_match.from_station in graph.graph.nodes and order_match.to_station in graph.graph.nodes
+    ]
+
+def filter_order_matches_same_region(order_matches: list[Trade], graph: Graph) -> list[Trade]:
+    """
+    Filters out order matches where the from_region and to_region are different.
+    Keeps only order matches within the same region.
+
+    Args:
+        order_matches: List of trade opportunities.
+        graph: Navigation graph.
+
+    Returns:
+        Filtered list of trade opportunities where both stations are in the same region.
+    """
+    filtered_order_matches = []
+
+    for order_match in order_matches:
+        from_station = order_match.from_station
+        to_station = order_match.to_station
+
+        from_station_data = graph.stations.get(from_station)
+        to_station_data = graph.stations.get(to_station)
+
+        if not from_station_data or not to_station_data:
+            continue  # Skip if station data is missing
+
+        from_solar_system_id = from_station_data["solar_system_id"]
+        to_solar_system_id = to_station_data["solar_system_id"]
+
+        from_region = graph.solar_systems[from_solar_system_id]["region_id"]
+        to_region = graph.solar_systems[to_solar_system_id]["region_id"]
+
+        if from_region == to_region:
+            filtered_order_matches.append(order_match)
+
+    return filtered_order_matches
+
+def calculate_net_profit(order_matches: list[Trade], graph: Graph, ship: Ship) -> list[Trade]:
+    """
+    Calculates the net profit for each order match by subtracting transport cost from gross profit.
+
+    Args:
+        order_matches: List of trade opportunities.
+        graph: Navigation graph.
+        ship: Ship parameters.
+
+    Returns:
+        List of trade opportunities with net_profit calculated.
+    """
+    logger.info("Calculating estimated profits")
+    for order_match in tqdm(order_matches):
+        try:
+            # Calculate transport cost from ship location to from_station
+            cost_to_source = graph.shortest_path_length(ship.location, order_match.from_station)
+            # Calculate transport cost from from_station to to_station
+            cost_to_destination = graph.shortest_path_length(order_match.from_station, order_match.to_station)
+
+            # Check if paths exist
+            if cost_to_source is None or cost_to_destination is None:
+                logger.warning(f"No path found for order match: {order_match}")
+                order_match.net_profit = None
+                continue
+
+            total_transport_cost = cost_to_source + cost_to_destination
+            order_match.net_profit = order_match.gross_profit - total_transport_cost
+        except Exception as e:
+            logger.error(f"Error calculating net profit for order match {order_match}: {e}")
+            order_match.net_profit = None
+
+    return order_matches
+
+def filter_order_matches_low_profit(order_matches: list[Trade]) -> list[Trade]:
+    """
+    Filters out order matches with non-positive net profit.
+
+    Args:
+        order_matches: List of trade opportunities with net_profit calculated.
+
+    Returns:
+        Filtered list of profitable trade opportunities.
+    """
+    return [
+        order_match for order_match in order_matches
+        if order_match.net_profit and order_match.net_profit > 0
+    ]