modelverse/integration/code/pn_interface.alc

include "primitives.alh"
include "constructors.alh"
include "object_operations.alh"
include "library.alh"
include "conformance_scd.alh"
include "io.alh"

Element function create_metamodels():
	// TODO
	//   For the moment, we make the assumption that it doesn't exist yet.
	//   We create both the Simple Class Diagrams model, retype it, and then make the metamodel as an instance of this
	//   In the future, this should already exist though...

	if (bool_not(dict_in(dict_read(read_root(), "__hierarchy"), "models"))):
		Element scd
		Element scd_model
		scd = create_node()
		scd_model = create_node()
		dict_add(scd, "model", scd_model)
		instantiate_bottom_node(scd, "Class")
		instantiate_bottom_value(scd, "Type", Type)
		instantiate_bottom_value(scd, "__String", String)
		instantiate_bottom_value(scd, "__name", "name")
		instantiate_bottom_edge(scd, "Attribute", dict_read(scd_model, "Class"), dict_read(scd_model, "Type"))
		instantiate_bottom_edge(scd, "__Name", dict_read(scd_model, "Attribute"), dict_read(scd_model, "__String"))
		instantiate_bottom_edge(scd, "Association", dict_read(scd_model, "Class"), dict_read(scd_model, "Class"))
		instantiate_bottom_edge(scd, "Inheritance", dict_read(scd_model, "Class"), dict_read(scd_model, "Class"))
		instantiate_bottom_edge(scd, "__name_edge", dict_read(scd_model, "__Name"), dict_read(scd_model, "__name"))
		instantiate_bottom_edge(scd, "__inh_1", dict_read(scd_model, "Association"), dict_read(scd_model, "Class"))
		instantiate_bottom_edge(scd, "__inh_2", dict_read(scd_model, "Attribute"), dict_read(scd_model, "Class"))
		instantiate_bottom_value(scd, "__attribute", "attribute")
		instantiate_bottom_edge(scd, "__attribute_edge", dict_read(scd_model, "Attribute"), dict_read(scd_model, "__attribute"))

		// Instantiated, now retype to make sure that everything is correct
		Element mapping
		mapping = create_node()
		dict_add(mapping, dict_read(scd_model, "Class"), dict_read(scd_model, "Class"))
		dict_add(mapping, dict_read(scd_model, "Type"), dict_read(scd_model, "Type"))
		dict_add(mapping, dict_read(scd_model, "__String"), dict_read(scd_model, "Type"))
		dict_add(mapping, dict_read(scd_model, "Attribute"), dict_read(scd_model, "Attribute"))
		dict_add(mapping, dict_read(scd_model, "__Name"), dict_read(scd_model, "Attribute"))
		dict_add(mapping, dict_read(scd_model, "Association"), dict_read(scd_model, "Association"))
		dict_add(mapping, dict_read(scd_model, "Inheritance"), dict_read(scd_model, "Association"))
		dict_add(mapping, dict_read(scd_model, "__inh_1"), dict_read(scd_model, "Inheritance"))
		dict_add(mapping, dict_read(scd_model, "__inh_2"), dict_read(scd_model, "Inheritance"))
		dict_add(mapping, dict_read(scd_model, "__name"), dict_read(scd_model, "__String"))
		dict_add(mapping, dict_read(scd_model, "__name_edge"), dict_read(scd_model, "__Name"))
		dict_add(mapping, dict_read(scd_model, "__attribute"), dict_read(scd_model, "__String"))
		dict_add(mapping, dict_read(scd_model, "__attribute_edge"), dict_read(scd_model, "__Name"))
		retype(scd, scd, dict_read(scd_model, "Inheritance"), mapping)
		export_node("models/SimpleClassDiagrams", scd)

		// TODO this code is also very dirty as there is no nice "dictionary" and "list" syntax yet
		Element pn_metamodel
		pn_metamodel = instantiate_new_model(scd, dict_read(scd_model, "Inheritance"))
		Element tokens
		tokens = create_node()
		dict_add(tokens, "tokens", Integer)
		instantiate_model_lib(pn_metamodel, dict_read(scd_model, "Class"), "Place", create_node(), tokens, create_node())
		instantiate_model_lib(pn_metamodel, dict_read(scd_model, "Class"), "Transition", create_node(), create_node(), create_node())
		Element weight
		weight = create_node()
		dict_add(weight, "weight", Integer)
		Element p2t_links
		p2t_links = create_node()
		list_append(p2t_links, dict_read(dict_read(pn_metamodel, "model"), "Place"))
		list_append(p2t_links, dict_read(dict_read(pn_metamodel, "model"), "Transition"))
		Element t2p_links
		t2p_links = create_node()
		list_append(t2p_links, dict_read(dict_read(pn_metamodel, "model"), "Transition"))
		list_append(t2p_links, dict_read(dict_read(pn_metamodel, "model"), "Place"))
		instantiate_model_lib(pn_metamodel, dict_read(scd_model, "Association"), "P2T", p2t_links, weight, create_node())
		instantiate_model_lib(pn_metamodel, dict_read(scd_model, "Association"), "T2P", t2p_links, weight, create_node())

		set_model_constraints(pn_metamodel, petrinet_constraints)
		export_node("models/PetriNets", pn_metamodel)

		// Also create conformance bottom metamodel
		Element mm_bottom
		Element mm_bottom_model
		mm_bottom = create_node()
		mm_bottom_model = create_node()
		dict_add(mm_bottom, "model", mm_bottom_model)
		instantiate_bottom_node(mm_bottom, "Node")
		instantiate_bottom_value(mm_bottom, "Type", Type)
		instantiate_bottom_value(mm_bottom, "Integer", Integer)
		instantiate_bottom_value(mm_bottom, "Action", Action)
		instantiate_bottom_value(mm_bottom, "Float", Float)
		instantiate_bottom_value(mm_bottom, "String", String)
		instantiate_bottom_value(mm_bottom, "Boolean", Boolean)
		instantiate_bottom_edge(mm_bottom, "Edge", dict_read(mm_bottom_model, "Node"), dict_read(mm_bottom_model, "Node"))
		instantiate_bottom_edge(mm_bottom, "__Inheritance", dict_read(mm_bottom_model, "Node"), dict_read(mm_bottom_model, "Node"))
		instantiate_bottom_edge(mm_bottom, "__inh_1", dict_read(mm_bottom_model, "Type"), dict_read(mm_bottom_model, "Node"))
		instantiate_bottom_edge(mm_bottom, "__inh_2", dict_read(mm_bottom_model, "Integer"), dict_read(mm_bottom_model, "Node"))
		instantiate_bottom_edge(mm_bottom, "__inh_3", dict_read(mm_bottom_model, "Action"), dict_read(mm_bottom_model, "Node"))
		instantiate_bottom_edge(mm_bottom, "__inh_4", dict_read(mm_bottom_model, "Float"), dict_read(mm_bottom_model, "Node"))
		instantiate_bottom_edge(mm_bottom, "__inh_5", dict_read(mm_bottom_model, "String"), dict_read(mm_bottom_model, "Node"))
		instantiate_bottom_edge(mm_bottom, "__inh_6", dict_read(mm_bottom_model, "Boolean"), dict_read(mm_bottom_model, "Node"))
		instantiate_bottom_edge(mm_bottom, "__inh_7", dict_read(mm_bottom_model, "Edge"), dict_read(mm_bottom_model, "Node"))

		// Retype it with itself
		mapping = create_node()
		dict_add(mapping, dict_read(mm_bottom_model, "Node"), dict_read(mm_bottom_model, "Node"))
		dict_add(mapping, dict_read(mm_bottom_model, "Type"), dict_read(mm_bottom_model, "Type"))
		dict_add(mapping, dict_read(mm_bottom_model, "Integer"), dict_read(mm_bottom_model, "Type"))
		dict_add(mapping, dict_read(mm_bottom_model, "Float"), dict_read(mm_bottom_model, "Type"))
		dict_add(mapping, dict_read(mm_bottom_model, "String"), dict_read(mm_bottom_model, "Type"))
		dict_add(mapping, dict_read(mm_bottom_model, "Boolean"), dict_read(mm_bottom_model, "Type"))
		dict_add(mapping, dict_read(mm_bottom_model, "Action"), dict_read(mm_bottom_model, "Type"))
		dict_add(mapping, dict_read(mm_bottom_model, "Edge"), dict_read(mm_bottom_model, "Edge"))
		dict_add(mapping, dict_read(mm_bottom_model, "__Inheritance"), dict_read(mm_bottom_model, "Edge"))
		dict_add(mapping, dict_read(mm_bottom_model, "__inh_1"), dict_read(mm_bottom_model, "__Inheritance"))
		dict_add(mapping, dict_read(mm_bottom_model, "__inh_2"), dict_read(mm_bottom_model, "__Inheritance"))
		dict_add(mapping, dict_read(mm_bottom_model, "__inh_3"), dict_read(mm_bottom_model, "__Inheritance"))
		dict_add(mapping, dict_read(mm_bottom_model, "__inh_4"), dict_read(mm_bottom_model, "__Inheritance"))
		dict_add(mapping, dict_read(mm_bottom_model, "__inh_5"), dict_read(mm_bottom_model, "__Inheritance"))
		dict_add(mapping, dict_read(mm_bottom_model, "__inh_6"), dict_read(mm_bottom_model, "__Inheritance"))
		dict_add(mapping, dict_read(mm_bottom_model, "__inh_7"), dict_read(mm_bottom_model, "__Inheritance"))
		retype(mm_bottom, mm_bottom, dict_read(mm_bottom_model, "__Inheritance"), mapping)
		export_node("models/LTM_bottom", mm_bottom)

	return 0

String function petrinet_constraints(pn_mo : Element):
	// Check places to have positive number of tokens
	Element all_elems
	Element elem_constraint
	all_elems = allInstances(pn_mo, dict_read(dict_read(dict_read(pn_mo, "metamodel"), "model"), "Place"))
	while (0 < read_nr_out(all_elems)):
		elem_constraint = set_pop(all_elems)
		if (integer_lt(readAttribute(pn_mo, elem_constraint, "tokens"), 0)):
			return "Negative number of tokens in Place " + getName(pn_mo, elem_constraint)

	// Check P2T transitions to have positive weight
	all_elems = allInstances(pn_mo, dict_read(dict_read(dict_read(pn_mo, "metamodel"), "model"), "P2T"))
	while (0 < read_nr_out(all_elems)):
		elem_constraint = set_pop(all_elems)
		if (integer_lt(readAttribute(pn_mo, elem_constraint, "weight"), 0)):
			return "Negative weight in arc " + getName(pn_mo, elem_constraint)

	// Check T2P transitions to have positive weight
	all_elems = allInstances(pn_mo, dict_read(dict_read(dict_read(pn_mo, "metamodel"), "model"), "T2P"))
	while (0 < read_nr_out(all_elems)):
		elem_constraint = set_pop(all_elems)
		if (integer_lt(readAttribute(pn_mo, elem_constraint, "weight"), 0)):
			return "Negative weight in arc " + getName(pn_mo, elem_constraint)

	return "OK"

Element function pn_operations():
	Element ops
	ops = create_node()
	dict_add(ops, "fire", petrinet_fire)
	dict_add(ops, "enabled", petrinet_enabled)
	return ops

Element function petrinet_enabled(pn_m : Element):
	Element set_enabled
	set_enabled = petrinet_enabled_set(pn_m)
	output("Enabled transitions:")
	while (0 < read_nr_out(set_enabled)):
		output(getName(pn_m, set_pop(set_enabled)))
	return pn_m

Element function petrinet_enabled_set(pn_mod : Element):
	Element all_transitions
	all_transitions = allInstances(pn_mod, dict_read(dict_read(dict_read(pn_mod, "metamodel"), "model"), "Transition"))

	Element enabled_transitions
	enabled_transitions = create_node()

	Element under_study
	Element in_arcs
	Element arc_under_study
	Boolean enabled
	while (0 < read_nr_out(all_transitions)):
		under_study = set_pop(all_transitions)
		enabled = True

		// Find all incoming transitions
		in_arcs = allIncomingAssociationInstances(pn_mod, under_study, dict_read(dict_read(dict_read(pn_mod, "metamodel"), "model"), "P2T"))

		while (0 < read_nr_out(in_arcs)):
			arc_under_study = set_pop(in_arcs)

			Integer present_tokens
			Integer required_tokens
			required_tokens = readAttribute(pn_mod, arc_under_study, "weight")
			present_tokens = readAttribute(pn_mod, read_edge_src(arc_under_study), "tokens")
			if (present_tokens < required_tokens):
				// Less tokens than required, so disable the transition completely
				enabled = False

		if (enabled):
			set_add(enabled_transitions, under_study)

	return enabled_transitions

Element function petrinet_fire(pn_mode : Element):
	output("Transition to fire?")
	Element transition
	transition = input()
	if (dict_in(dict_read(pn_mode, "model"), transition)):
		transition = dict_read(dict_read(pn_mode, "model"), transition)
		if (set_in(petrinet_enabled_set(pn_mode), transition)):
			Element workset
			Element working_place
			Element working_arc

			// Consume tokens
			workset = allIncomingAssociationInstances(pn_mode, transition, dict_read(dict_read(dict_read(pn_mode, "metamodel"), "model"), "P2T"))
			while (0 < read_nr_out(workset)):
				working_arc = set_pop(workset)
				working_place = read_edge_src(working_arc)
				setAttribute(pn_mode, working_place, "tokens", integer_subtraction(readAttribute(pn_mode, working_place, "tokens"), readAttribute(pn_mode, working_arc, "weight")))
				output((("  " + getName(pn_mode, working_place)) + ": ") + cast_i2s(readAttribute(pn_mode, working_place, "tokens")))

			// Add tokens
			workset = allOutgoingAssociationInstances(pn_mode, transition, dict_read(dict_read(dict_read(pn_mode, "metamodel"), "model"), "T2P"))
			while (0 < read_nr_out(workset)):
				working_arc = set_pop(workset)
				working_place = read_edge_dst(working_arc)
				setAttribute(pn_mode, working_place, "tokens", integer_addition(readAttribute(pn_mode, working_place, "tokens"), readAttribute(pn_mode, working_arc, "weight")))
				output((("  " + getName(pn_mode, working_place)) + ": ") + cast_i2s(readAttribute(pn_mode, working_place, "tokens")))
			output("Transition fired!")
		else:
			output("Cannot fire if not enabled; aborting")
	else:
		output("Unknown transition; aborting")
	return pn_mode
	
Element function petrinet_loaded(pn_model : Element):
	String cmd

	Element attr_list_pn
	Element attr_keys_pn
	String attr_key_pn
	Element metamodel_element_pn
	String typename
	Boolean bottom
	Element other_metamodel

	bottom = False
	other_metamodel = create_node()
	dict_add(other_metamodel, "model", dict_read(pn_model, "model"))
	dict_add(other_metamodel, "type_mapping", create_node())
	dict_add(other_metamodel, "metamodel", import_node("models/LTM_bottom"))
	dict_add(other_metamodel, "inheritance", dict_read(dict_read(dict_read(other_metamodel, "metamodel"), "model"), "__Inheritance"))

	output("Model loaded, ready for commands!")
	output("Use 'help' command for a list of possible commands")

	while (True):
		output("Please give your command.")
		cmd = input()
		if (cmd == "help"):
			output("Generic model operations:")
			output("  instantiate -- Create a new model element")
			output("  delete      -- Delete an existing element")
			output("  modify      -- Modify attribute of an existing element")
			output("  rename      -- Rename an existing element")
			output("  list        -- Prints the list of elements in the model")
			output("  types       -- Prints the list of elements that can be instantiated")
			output("  read        -- Prints the current state of a model element")
			output("  verify      -- Check whether the model conforms to the metamodel")
			output("  retype      -- Change the type of an element")
			output("  switch      -- Switch between conformance bottom and the linguistic metamodel")
			output("  exit        -- Unload the model and go back to the loading prompt")
			if (bool_not(bottom)):
				output("Model-specific operations:")
				Element specific_ops
				specific_ops = dict_keys(pn_operations())
				String specific_op
				while (0 < dict_len(specific_ops)):
					specific_op = set_pop(specific_ops)
					output("  " + specific_op)
		elif (cmd == "exit"):
			return pn_model
		elif (cmd == "instantiate"):
			String mm_type_name
			output("Type to instantiate?")
			mm_type_name = input()
			if (dict_in(dict_read(dict_read(pn_model, "metamodel"), "model"), mm_type_name)):
				metamodel_element_pn = dict_read(dict_read(dict_read(pn_model, "metamodel"), "model"), mm_type_name)
				String element_name
				output("Name of new element?")
				element_name = input()
				if (dict_in(dict_read(pn_model, "model"), element_name)):
					output("Element already exists; aborting")
				else:
					Boolean cnt
					cnt = True
					Element additional_opts
					additional_opts = create_node()
					if (is_edge(metamodel_element_pn)):
						output("Source name?")
						String src_name
						src_name = input()
						if (dict_in(dict_read(pn_model, "model"), src_name)):
							list_append(additional_opts, dict_read(dict_read(pn_model, "model"), src_name))
							output("Destination name?")
							String dst_name
							dst_name = input()
							if (dict_in(dict_read(pn_model, "model"), dst_name)):
								list_append(additional_opts, dict_read(dict_read(pn_model, "model"), dst_name))
							else:
								output("Unknown destination; aborting")
								cnt = False
						else:
							output("Unknown source; aborting")
							cnt = False
					if (type_eq(typeof(metamodel_element_pn), Type)):
						// It is a value
						output("Value?")
						list_append(additional_opts, input())
					if (cnt):
						attr_list_pn = getAttributeList(pn_model, metamodel_element_pn)
						attr_keys_pn = dict_keys(attr_list_pn)
						Element attrs
						attrs = create_node()
						while (0 < read_nr_out(attr_keys_pn)):
							attr_key_pn = set_pop(attr_keys_pn)
							output(((attr_key_pn + " : ") + cast_t2s(dict_read(attr_list_pn, attr_key_pn))) + "?")
							dict_add(attrs, attr_key_pn, input())
						Element resulting_element
						resulting_element = instantiate_model_lib(pn_model, metamodel_element_pn, element_name, additional_opts, create_node(), attrs)
						output("Instantiation successful!")
			else:
				output("Unknown type specified; aborting")
		elif (cmd == "delete"):
			output("What is the name of the element you want to delete?")
			cmd = input()
			if (dict_in(dict_read(pn_model, "model"), cmd)):
				delete_element(dict_read(dict_read(pn_model, "model"), cmd))
				output("Deleted!")
			else:
				output("No such element; aborting")
		elif (cmd == "modify"):
			output("Element to modify?")
			cmd = input()
			if (dict_in(dict_read(pn_model, "model"), cmd)):
				Element mod
				mod = dict_read(dict_read(pn_model, "model"), cmd)
				metamodel_element_pn = dict_read_node(dict_read(pn_model, "type_mapping"), mod)

				attr_list_pn = getAttributeList(pn_model, metamodel_element_pn)
				attr_keys_pn = dict_keys(attr_list_pn)
				while (0 < read_nr_out(attr_keys_pn)):
					attr_key_pn = set_pop(attr_keys_pn)
					output((("   " + attr_key_pn) + " : ") + cast_t2s(dict_read(attr_list_pn, attr_key_pn)))

				output("Attribute to modify?")
				String attr_name
				attr_name = input()
				if (set_in(dict_keys(getAttributeList(pn_model, metamodel_element_pn)), attr_name)):
					output("New value?")
					setAttribute(pn_model, mod, attr_name, input())
					output("Modified!")
				else:
					output("Unknown attribute; aborting")
			else:
				output("Element does not exist; aborting")
		elif (cmd == "rename"):
			output("Old name?")
			String old_name_e
			old_name_e = input()
			if (dict_in(dict_read(pn_model, "model"), old_name_e)):
				output("New name?")
				String new_name_e
				new_name_e = input()
				if (dict_in(dict_read(pn_model, "model"), new_name_e)):
					output("New name already used; aborting")
				else:
					dict_add(dict_read(pn_model, "model"), new_name_e, dict_read(dict_read(pn_model, "model"), old_name_e))
					dict_delete(dict_read(pn_model, "model"), old_name_e)
					output("Rename complete!")
			else:
				output("Unknown element; aborting")
		elif (cmd == "list"):
			Element keys_m
			keys_m = dict_keys(dict_read(pn_model, "model"))
			output("List of all elements:")
			String v_m
			while (read_nr_out(keys_m) > 0):
				v_m = set_pop(keys_m)
				// Filter out anonymous objects
				typename = getName(dict_read(pn_model, "metamodel"), dict_read_node(dict_read(pn_model, "type_mapping"), dict_read(dict_read(pn_model, "model"), v_m)))
				if (bool_not(string_startswith(v_m, "__"))):
					output((("  " + v_m) + " : ") + typename)
		elif (cmd == "read"):
			output("Element to read?")
			cmd = input()
			if (dict_in(dict_read(pn_model, "model"), cmd)):
				Element read_elem
				read_elem = dict_read(dict_read(pn_model, "model"), cmd)
				metamodel_element_pn = dict_read_node(dict_read(pn_model, "type_mapping"), read_elem)

				output("Name: " + cmd)
				output("Type: " + getName(dict_read(pn_model, "metamodel"), metamodel_element_pn))
				if (is_edge(read_elem)):
					output("Source: " + getName(pn_model, read_edge_src(read_elem)))
					output("Destination: " + getName(pn_model, read_edge_dst(read_elem)))
				if (cast_v2s(read_elem) != "None"):
					output("Value: " + cast_v2s(read_elem))
				output("Defines attributes:")
				attr_list_pn = getInstantiatableAttributes(pn_model, read_elem)
				attr_keys_pn = dict_keys(attr_list_pn)
				while (0 < read_nr_out(attr_keys_pn)):
					attr_key_pn = set_pop(attr_keys_pn)
					output(((("   " + attr_key_pn) + " : ") + cast_t2s(dict_read(attr_list_pn, attr_key_pn))))
				output("Attributes:")
				attr_list_pn = getAttributeList(pn_model, metamodel_element_pn)
				attr_keys_pn = dict_keys(attr_list_pn)
				while (0 < read_nr_out(attr_keys_pn)):
					attr_key_pn = set_pop(attr_keys_pn)
					output((((("   " + attr_key_pn) + " : ") + cast_t2s(dict_read(attr_list_pn, attr_key_pn))) + " = ") + cast_v2s(readAttribute(pn_model, read_elem, attr_key_pn)))
			else:
				output("Unknown element; aborting")
		elif (cmd == "verify"):
			output(conformance_scd(pn_model))
		elif (cmd == "types"):
			Element keys_t
			keys_t = dict_keys(dict_read(dict_read(pn_model, "metamodel"), "model"))
			output("List of types:")
			String v_t
			while (read_nr_out(keys_t) > 0):
				v_t = set_pop(keys_t)
				if (bool_not(string_startswith(v_t, "__"))):
					output(string_join(("  " + v_t) + " : ", getName(dict_read(dict_read(pn_model, "metamodel"), "metamodel"), dict_read_node(dict_read(dict_read(pn_model, "metamodel"), "type_mapping"), dict_read(dict_read(dict_read(pn_model, "metamodel"), "model"), v_t)))))
		elif (cmd == "retype"):
			output("Element to retype?")
			String elementname
			elementname = input()
			if (dict_in(dict_read(pn_model, "model"), elementname)):
				output("New type")
				typename = input()
				if (dict_in(dict_read(dict_read(pn_model, "metamodel"), "model"), typename)):
					// OK, do the retyping
					// First try removing the previous type if it exists
					dict_delete(dict_read(pn_model, "type_mapping"), dict_read(dict_read(pn_model, "model"), elementname))
					// Now add the new type
					dict_add(dict_read(pn_model, "type_mapping"), dict_read(dict_read(pn_model, "model"), elementname), dict_read(dict_read(dict_read(pn_model, "metamodel"), "model"), typename))
					output("Retyped!")
				else:
					output("Unknown type; aborting")
			else:
				output("Unknown element; aborting")
		elif (cmd == "switch"):
			bottom = bool_not(bottom)

			Element tmp_model
			tmp_model = pn_model
			pn_model = other_metamodel
			other_metamodel = tmp_model

			if (bottom):
				// The type mapping we are using is probably not complete for our model
				// so we completely recreate it from the model we have.
				output("Switching to conformance bottom mode!")
				generate_bottom_type_mapping(pn_model)
			else:
				// We already switched the models and such, so we are already done!
				output("Switching to linguistic metamodel!")
		elif (bool_and(dict_in(pn_operations(), cmd), bool_not(bottom))):
			// A model-specific operation, so execute that one
			Element specific_op
			specific_op = dict_read(pn_operations(), cmd)
			specific_op(pn_model)
		else:
			output("Unknown command; aborting")
			output("Use command 'help' to get a list of available commands")

Element function initial_prompt():
	output("Welcome to the Model Management Interface, running live on the Modelverse!")
	output("Use 'help' command for a list of possible commands")
	String command
	Element root
	Element metamodel
	String name
	Element my_model
	String mm_name

	create_metamodels()

	dict_add(dict_read(read_root(), "__hierarchy"), "models", create_node())
	root = dict_read(dict_read(read_root(), "__hierarchy"), "models")

	while (True):
		output("Please give your command.")
		command = input()

		if (command == "help"):
			output("Currently no model is loaded, so your operations are limited to:")
			output("  new    -- Create a new model and save it for future use")
			output("  load   -- Load a previously made model")
			output("  rename -- Rename a previously made model")
			output("  delete -- Delete a previously made model")
			output("  list   -- Show a list of all stored models")
			output("  help   -- Show a list of possible commands")
		elif (command == "new"):
			output("Metamodel to instantiate?")
			mm_name = input()
			if (dict_in(root, mm_name)):
				output("Name of model?")
				name = input()
				if (dict_in(root, name)):
					output("Model exists; aborting")
				else:
					my_model = instantiate_new_model(dict_read(root, mm_name), create_node())
					dict_add(root, name, my_model)
					petrinet_loaded(my_model)
			else:
				output("Unknown metamodel; aborting")
		elif (command == "load"):
			output("Model to load?")
			name = input()
			if (dict_in(root, name)):
				my_model = dict_read(root, name)
				petrinet_loaded(my_model)
			else:
				output("Model not found; aborting")
		elif (command == "list"):
			Element keys
			keys = dict_keys(root)
			output("Found models:")
			String m_menu_list
			while (read_nr_out(keys) > 0):
				m_menu_list = set_pop(keys)
				output((("  " + m_menu_list) + " : ") + reverseNameLookup(root, dict_read(dict_read(root, m_menu_list), "metamodel")))
		elif (command == "delete"):
			output("Model to delete?")
			name = input()
			if (dict_in(root, name)):
				dict_delete(root, name)
				output("Deleted!")
			else:
				output("Model not found; aborting")
		elif (command == "rename"):
			output("Old name?")
			String old_name
			old_name = input()
			if (dict_in(root, old_name)):
				output("New name?")
				String new_name
				new_name = input()
				if (dict_in(root, new_name)):
					output("Model exists; aborting")
				else:
					dict_add(root, new_name, dict_read(root, old_name))
					dict_delete(root, old_name)
					output("Rename complete!")
			else:
				output("Model not found; aborting")
		else:
			output("Command not recognized, use 'help' for a list of possible commands")

Void function main():
	initial_prompt()