Make lead times specific to raw material and upstream node, not finished product and downstream node

[LarrySnyder]

See implications, e.g., at

stockpyl/src/stockpyl/node_state_vars.py

Lines 177 to 183 in be47a36

	for prod_index in self.node.product_indices:
	if rm_index in self.node.raw_materials_by_product(product=prod_index, return_indices=True, network_BOM=True) and \
	p_index in self.node.raw_material_suppliers_by_raw_material(raw_material=rm_index, return_indices=True, network_BOM=True):
	# Get lead times for this product. # TODO: shouldn't inbound shipment pipeline only use shipment LT, not order LT?
	order_lead_time = (self.node.get_attribute('order_lead_time', product=prod_index) or 0)
	shipment_lead_time = (self.node.get_attribute('shipment_lead_time', product=prod_index) or 0)
	self.inbound_shipment_pipeline[p_index][rm_index] = [0] * (order_lead_time + shipment_lead_time + 1)

stockpyl/src/stockpyl/sim.py

Lines 387 to 390 in 26792d6

	# Get lead times and product index (for convenience).
	# TODO: LTs should live with the RM, not the FG. Otherwise, different RMs can't have different LTs. (But this doesn't mean interpret LT as applying to the outbound link instead of the inbound.)
	order_lead_time = node.get_attribute('order_lead_time', prod) or 0
	shipment_lead_time = node.get_attribute('shipment_lead_time', prod) or 0

stockpyl/src/stockpyl/sim.py

Lines 839 to 842 in 26792d6

	# TODO: fix this
	prod = node.products_by_raw_material(rm_index)[0]
	OLT = node.get_attribute('order_lead_time', prod) or 0
	SLT = node.get_attribute('shipment_lead_time', prod) or 0

stockpyl/src/stockpyl/sim.py

Lines 1079 to 1086 in 26792d6

	# Find a product at successor node that uses prod_index from node as a raw material,
	# and use its lead time. If there is more than one such product, use the last one found.
	# This is a little klugey. # TODO: improve? should LTs be an attribute of the RM, not the product?
	for FG_index in s.product_indices:
	if prod_index in s.raw_materials_by_product(product=FG_index, return_indices=True, network_BOM=True) and \
	node.index in s.raw_material_suppliers_by_raw_material(raw_material=prod_index, return_indices=True, network_BOM=True):
	# Get lead time for this product.
	shipment_lead_time = (s.get_attribute('shipment_lead_time', product=FG_index) or 0)

Note: This doesn't mean we should interpret the LT as applying to the outbound link instead of the inbound link.

[LarrySnyder]

Related: shouldn't inbound shipment pipeline only use shipment LT, not order LT? (see line 180 above)

[LarrySnyder]

stockpyl/src/stockpyl/node_state_vars.py

Lines 205 to 215 in 2f2b0ab

	self.inbound_order_pipeline[s_index] = {}
	for prod_index in self.node.product_indices:
	# Does s order prod_index from node?
	if prod_index in s.raw_materials_by_product(product='all', return_indices=True, network_BOM=True) \
	and node.index in s.raw_material_suppliers_by_raw_material(raw_material=prod_index, return_indices=True, network_BOM=True):
	# Find a product at s that orders this raw material at node, to get its order_lead_time.
	downstream_prod_index = s.products_by_raw_material(prod_index)[0]
	order_lead_time = s.get_attribute('order_lead_time', product=downstream_prod_index) or 0
	else:
	order_lead_time = 0
	self.inbound_order_pipeline[s_index][prod_index] = [0] * (order_lead_time + 1)