include "primitives.alh"
include "modelling.alh"
include "object_operations.alh"
include "utils.alh"
include "random.alh"

Void function print_states(model : Element, data : Element):
	Element classes
	Element states
	Element class
	String state

	log("Current states:")
	classes = set_copy(data["classes"])
	while (read_nr_out(classes) > 0):
		class = set_pop(classes)
		log(string_join(string_join(string_join("  ", class["ID"]), " : "), read_attribute(model, class["type"], "name")))

		states = set_copy(class["states"])
		while (read_nr_out(states) > 0):
			state = set_pop(states)
			log(string_join("    ", read_attribute(model, state, "name")))

	return!

Element function filter(model : Element, set : Element, attribute_name : String, attribute_value : Element):
	Element keys
	String key
	Element result

	result = create_node()
	while (read_nr_out(set) > 0):
		key = set_pop(set)
		if (value_eq(read_attribute(model, key, attribute_name), attribute_value)):
			set_add(result, key)

	return result!

Element function expand_state(model : Element, state : String):
	String t
	t = read_type(model, state)
	if (t == "SCCD/CompositeState"):
		// Recurse further in the composite
		return expand_composite_state(model, state)!
	elif (t == "SCCD/ParallelState"):
		// Split up all components
		return expand_parallel_state(model, state)!
	else:
		// Probably just an atomic, so return this one only
		Element result
		result = create_node()
		set_add(result, state)
		return result!

Element function expand_composite_state(model : Element, composite_state : String):
	// Resolve all initial states from a single composite state
	String initial

	// Fetch the initial state
	initial = set_pop(filter(model, allAssociationDestinations(model, composite_state, "SCCD/composite_children"), "isInitial", True))
	log("Got initial state: " + initial)

	// Expand the initial state, depending on what it is
	return expand_state(model, initial)!

Element function expand_parallel_state(model : Element, parallel_state : String):
	// Resolve all initial states from a single parallel state
    Element children
	Element result
	Element expanded_children

	children = allAssociationDestinations(model, parallel_state, "SCCD/parallel_children")
	result = create_node()

	while (read_nr_out(children) > 0):
		set_merge(result, expand_state(model, set_pop(children)))

	return result!

Void function start_class(model : Element, data : Element, class : String):
	// Start up the class and assign its initial state to it

	// Create the data structure for a running class
	Element class_handle
	class_handle = create_node()
	dict_add(class_handle, "type", class)
	dict_add(class_handle, "ID", cast_id2s(create_node()))

	// Add the current state of the class
	String initial_state
	// Should only be one behaviour linked to it!
	initial_state = set_pop(allAssociationDestinations(model, class, "SCCD/behaviour"))
	dict_add(class_handle, "states", expand_state(model, initial_state))

	set_add(data["classes"], class_handle)

	return!

Element function get_enabled_transitions(model : Element, state : String, interrupt : Element):
	// Returns all enabled transitions
	// TODO ignore conditions and afters
	Element result
	Element to_filter
	String attr
	String transition

	result = create_node()
	to_filter = allOutgoingAssociationInstances(model, state, "SCCD/transition")

	while (read_nr_out(to_filter) > 0):
		transition = set_pop(to_filter)
		attr = read_attribute(model, transition, "event")
		if (element_eq(attr, read_root())):
			// No event defined, so is fine
			set_add(result, transition)
		elif (value_eq(attr, interrupt)):
			// Event defined, and that is the one of the event we got in
			set_add(result, transition)

	return result!

Float function step_class(model : Element, data : Element, class : Element, interrupt : Element):
	// Find enabled transitions in a class and execute it, updating the state
	// Iterate over all current states, searching for enabled transitions
	// Search for enabled transitions in higher levels as well!
	Element states
	Element new_states
	String state
	Element transitions
	String transition

	log(string_join("Stepping ", class["ID"]))
	states = set_copy(class["states"])
	new_states = create_node()

	while (read_nr_out(states) > 0):
		state = set_pop(states)

		// Fetch transitions in this state specifically (NO parent)
		transitions = get_enabled_transitions(model, state, interrupt)
		log("Got enabled transitions: " + cast_v2s(read_nr_out(transitions)))
		if (read_nr_out(transitions) != 0):
			// Found an enabled transition, so store that one
			transition = random_choice(transitions)
			log("Executing enabled transition: " + cast_v2s(read_attribute(model, transition, "name")))

			set_add(new_states, readAssociationDestination(model, transition))
			log("Found new state: " + cast_v2s(read_attribute(model, readAssociationDestination(model, transition), "name")))
		else:
			// Try going to the parent
			// TODO

			// Nothing found, so stay in the current state
			set_add(new_states, state)

	// Update states
	dict_overwrite(class, "states", new_states)

	return 1.0!

Float function step(model : Element, data : Element, interrupt : Element):
	// Step through all classes
	Element classes
	Element class
	Float t_min
	Float t_class

	t_min = 99999.0
	classes = set_copy(data["classes"])

	while (read_nr_out(classes) > 0):
		class = set_pop(classes)
		t_class = step_class(model, data, class, interrupt)
		if (t_class < t_min):
			t_min = t_class

	return t_min!

Boolean function main(model : Element):
	// Executes the provided SCCD model
	Element data
	data = create_node()
	dict_add(data, "classes", create_node())

	// Prepare for input
	output("Ready for input!")

	// Find initial
	String default_class
	default_class = set_pop(filter(model, allInstances(model, "SCCD/Class"), "default", True))
	log("Found default class: " + default_class)

	// Start up the default class
	start_class(model, data, default_class)

	Float timeout
	Element interrupt
	timeout = 0.0
	while (True):
		print_states(model, data)
		interrupt = input_timeout(timeout)

		if (value_eq(interrupt, "#EXIT#")):
			// Stop execution
			return True!

		if (element_neq(interrupt, read_root())):
			// Got interrupt
			log("Got event: " + cast_v2s(interrupt))
			output("Processed event, ready for more!")

		timeout = step(model, data, interrupt)

	return True!