import pandas as pd
from datetime import datetime
def calc_requirements(bom, schedule):
req = {}
for product, qty in schedule.items():
for mat, per_unit in bom[product].items():
req[mat] = req.get(mat, 0) + per_unit * qty
return req
def check_stock(requirements, inventory):
orders = {}
for mat, needed in requirements.items():
available = inventory.get(mat, 0)
if needed > available:
orders[mat] = needed - available
return orders
# Generate material plan