add contract pdf generation

backend/src/contracts/contracts.py

@@ -1,3 +1,108 @@
-from fastapi import APIRouter
+from fastapi import APIRouter, Depends
+from fastapi.responses import StreamingResponse
+from src.database import get_session
+from sqlmodel import Session
+import src.forms.service as form_service
+import src.shipments.service as shipment_service
+import src.products.service as product_service
+from src.contracts.generate_contract import generate_html_contract
+import src.models as models
+from src.messages import PDFerrorOccured
+import io
 
 router = APIRouter(prefix='/contracts')
+
+def find_dict_in_list(lst, key, value):
+    for i, dic in enumerate(lst):
+        if dic[key].id == value:
+            return i
+    return -1
+
+def extract_products(session: Session, contract: dict):
+    planned = []
+    recurrent = []
+    for key in contract.keys():
+        key_list = key.split("-")
+        if "planned" in key:
+            shipment_id = int(key_list[1])
+            product_id = int(key_list[2])
+            shipment = shipment_service.get_one(session, shipment_id)
+            product = product_service.get_one(session, product_id)
+
+            existing_id = find_dict_in_list(planned, "shipment", shipment_id)
+            if existing_id >= 0:
+                planned[existing_id]["products"].append({
+                    "product": product,
+                    "quantity": contract[key],
+                })
+                planned[existing_id]['price'] += compute_product_price(product, contract[key])
+            else:
+                planned.append({
+                    "shipment": shipment,
+                    "price": compute_product_price(product, contract[key]),
+                    "products": [{
+                        "product": product,
+                        "quantity": contract[key],
+                    }]
+                })
+        if "recurrent" in key:
+            product_id = int(key_list[1])
+            product = product_service.get_one(session, product_id)
+            recurrent.append({
+                "product": product,
+                "quantity": contract[key]
+            })
+    return planned, recurrent
+
+def compute_product_price(product: models.Product, quantity: int, nb_shipment: int = 1):
+    product_quantity_unit = 1 if product.unit == models.Unit.KILO else 1000
+    final_quantity = quantity if product.price else quantity / product_quantity_unit
+    final_price = product.price if product.price else product.price_kg
+    return final_price * final_quantity * nb_shipment 
+
+def compute_recurrent_prices(products_quantities: list[dict], nb_shipment: int):
+    result = 0
+    for product_quantity in products_quantities:
+        product = product_quantity['product']
+        quantity = product_quantity['quantity']
+        result += compute_product_price(product, quantity, nb_shipment)
+    return result
+
+def compute_planned_prices(planned: list[dict]):
+    result = 0
+    for plan in planned:
+        result += plan['price']
+    return result
+
+@router.post('/')
+async def create_contract(
+    contract: models.ContractBase,
+    session: Session = Depends(get_session)
+):
+    form = form_service.get_one(session, contract.form_id)
+    planned, recurrent = extract_products(session, contract.contract)
+    recurrent_price = compute_recurrent_prices(recurrent, len(form.shipments))
+    total_price = '{:10.2f}'.format(recurrent_price + compute_planned_prices(planned))
+    # TODO: Store contract
+    # TODO: send contract to referer
+    # TODO: Store contract informations ?
+    try:
+        pdf_bytes = generate_html_contract(
+            form, 
+            contract.contract, 
+            planned, 
+            recurrent, 
+            '{:10.2f}'.format(recurrent_price),
+            total_price
+        )
+        pdf_file = io.BytesIO(pdf_bytes)
+        contract_id = f'{contract.contract['firstname']}_{contract.contract['lastname']}_{form.productor.type}_{form.season}'
+    except:
+        raise HTTPException(status_code=400, detail=PDFerrorOccured)
+    return StreamingResponse(
+        pdf_file,
+        media_type="application/pdf",
+        headers={
+            "Content-Disposition": f"attachement; filename=contract_{contract_id}.pdf"
+        }
+    )