alai/src/state_machine/StateMachine.cpp

#include "StateMachine.h"
#include "State.h"

using namespace godot;

void StateMachine::_register_methods()
{
    register_method("_ready", &StateMachine::_ready);
    register_method("_on_StateMachine_tree_entered", &StateMachine::_on_StateMachine_tree_entered);
    register_method("_on_StateMachine_tree_exiting", &StateMachine::_on_StateMachine_tree_exiting);
    register_property<StateMachine, String>("default_state", &StateMachine::set_default_state, &StateMachine::get_default_state, String());
    register_property<StateMachine, bool>("debug", &StateMachine::set_debug, &StateMachine::get_debug, false);
    register_signal<StateMachine>("state_entered", "state", GODOT_VARIANT_TYPE_STRING);
    register_signal<StateMachine>("state_exited", "state", GODOT_VARIANT_TYPE_STRING);
    register_signal<StateMachine>("state_restarted", "state", GODOT_VARIANT_TYPE_STRING);
}

StateMachine::StateMachine()
{
}

StateMachine::~StateMachine()
{
}

void StateMachine::_init()
{
    set_default_state(String());
    set_debug(false);
}

void StateMachine::_ready()
{
    connect("tree_entered", this, "_on_StateMachine_tree_entered");
    connect("tree_exiting", this, "_on_StateMachine_tree_exiting");
    parent = get_parent();
    set_current_state(get_default_state());
    setup();
}

void StateMachine::setup()
{
    auto children = get_children();

    if (get_current_state() == "")
    {
        if (children.size() > 0)
        {
            WARN_PRINT("State machine doesn't have a default state set, using first child!");
            auto child = Object::cast_to<Node>(children[0].operator Object*());
            set_current_state(child->get_name());
        }
        else
        {
            ERR_PRINT("State machine doesn't have a default state set and has no child states!");
            return;
        }
    }

    for (uint8_t i = 0; i < children.size(); i++)
    {
        auto child = Object::cast_to<Node>(children[i].operator Object*());
        add_state(child->get_name(), child);

        child->call("set_state_machine", this);

        child->call("set_parent", parent);

        if (child->get_name() != get_current_state())
        {
            this->remove_child(child);
        }
    }

    this->call("_state_enter", get_current_state());
}

void StateMachine::add_state(const String state, Node *child)
{
    states[state] = child;
}

bool StateMachine::is_current(const String state)
{
    if (get_current_state() == "")
    {
        return false;
    }
    else
    {
        return get_current_state() == state;
    }
}

bool StateMachine::has(const String state)
{
    return states.has(state);
}

void StateMachine::restart(const String state, const Array& args)
{
    this->call("_state_exit", state, args);
    this->call("_state_enter", state, args);
    this->emit_signal("state_restarted", get_current_state());
}

void StateMachine::change(const String state, const Array &args)
{
    if (is_current(state))
    {
        return this->restart(state, args);
    }

    auto previous_state = get_current_state();
    auto exiting = this->call("_state_exit", state, args);

    if (get_current_state() != "")
    {
        auto child = Object::cast_to<Node>(states[get_current_state()].operator Object*());
        if (child != nullptr)
        {
            this->remove_child(child);
        }
        this->emit_signal("state_exited", get_current_state());
        if (debug)
        {
            Godot::print(get_current_state() + " exited!");
        }
    }

    set_current_state(state);
    auto child = Object::cast_to<Node>(states[get_current_state()].operator Object*());
    this->add_child(child);

    this->call("_state_enter", previous_state, args);
    this->emit_signal("state_entered", get_current_state());
    if (debug)
    {
        Godot::print(get_current_state() + " entered!");
    }
}

Variant StateMachine::call(const String method, const Array &args)
{
    auto node = Object::cast_to<Node>(states[get_current_state()].operator Object*());
    if (node != nullptr)
    {
        return node->call(method, args);
    }
    return Variant();
}

Variant StateMachine::_call(const String method, const Array &args)
{
    return this->call(method, args);
}

void StateMachine::set_default_state(const String new_default_state)
{
    default_state = new_default_state;
}

String StateMachine::get_default_state()
{
    return default_state;
}

void StateMachine::set_current_state(const String new_current_sate)
{
    current_state = new_current_sate;
}

String StateMachine::get_current_state()
{
    return current_state;
}

void StateMachine::set_debug(bool debug)
{
    this->debug = debug;
}

bool StateMachine::get_debug()
{
    return this->debug;
}

void StateMachine::_on_StateMachine_tree_entered()
{
    setup();
}

void StateMachine::_on_StateMachine_tree_exiting()
{
    auto keys = states.keys();
    for (uint8_t i = 0; i < keys.size(); i++)
    {
        auto child = Object::cast_to<Node>(states[keys[i]].operator Object*());
        if (child != nullptr)
        {
            auto children = get_children();
            if (!children.has(child))
            {
                this->add_child(child);
            }
        }
    }
}