more inventory management work

app/contexts/inventory_item.py

@@ -0,0 +1,81 @@
+from app.services.base_service import BaseService
+from app.models.inventory_management import InventoryItem
+from app.models.tcgplayer_product import TCGPlayerProduct
+from app.contexts.inventory_product import InventoryProductContext
+from sqlalchemy.orm import Session
+from datetime import datetime
+
+
+class InventoryItemContext:
+    def __init__(self, item: InventoryItem, db: Session):
+        self.item = item
+        self.physical_item = item.physical_item
+        self.marketplace_listing = item.marketplace_listing
+        self.parent = item.parent
+        self.children = item.children
+        self.product = item.physical_item.product
+        self.db = db
+
+    @property
+    def cost_basis(self) -> float:
+        return self.item.cost_basis
+    
+    @property
+    def product_id(self) -> int:
+        return self.physical_item.product_id
+    
+    @property
+    def product_name(self) -> str:
+        return self.physical_item.product_name
+    
+    @property
+    def item_type(self) -> str:
+        return self.physical_item.item_type
+    
+    @property
+    def market_price(self) -> float:
+        return self.product.most_recent_tcgplayer_price.market_price
+    
+    @property
+    def tcg_low_price(self) -> float:
+        return self.product.most_recent_tcgplayer_price.low_price
+    
+    @property
+    def listed_price(self) -> float:
+        return self.marketplace_listing.listed_price
+    
+    def top_level_parent(self) -> "InventoryItemContext":
+        if self.parent:
+            return self.parent.top_level_parent()
+        else:
+            return self
+    
+    def box_expected_value(self) -> float:
+        top_level_parent_item = self.top_level_parent_item()
+        if 'case' in top_level_parent_item.item_type:
+            return top_level_parent_item.open_event.sealed_case.expected_value
+        elif 'box' in top_level_parent_item.item_type:
+            return top_level_parent_item.open_event.sealed_box.expected_value
+        else:
+            raise ValueError("Unknown top level parent item type")
+
+    def box_acquisition_cost(self) -> float:
+        if self.physical_item.transaction_item:
+            return self.physical_item.transaction_item.unit_price
+        elif self.parent:
+            return self.parent.box_acquisition_cost()
+        else:
+            raise ValueError("Cannot find transaction unit price for this item")
+    
+    def age_on_marketplace(self) -> int:
+        return (datetime.now() - self.marketplace_listing.listing_date).days    
+    
+class InventoryItemContextFactory:
+    def __init__(self, db: Session):
+        self.db = db
+
+    def get_context(self, item: InventoryItem) -> InventoryItemContext:
+        return InventoryItemContext(item, self.db)
+    
+    def get_context_for_product(self, product: TCGPlayerProduct) -> InventoryProductContext:
+        return InventoryProductContext(product, self.db)