Double Event Loop A5

#include <allegro5/allegro.h>
#include <allegro5/allegro_font.h>
#include <allegro5/allegro_ttf.h>
#include <cstdio>

// `pkg-config --libs allegro-5.1 allegro_font-5.1 allegro_ttf-5.1`

using namespace std;

const int SCREEN_X = 800;
const int SCREEN_Y = 600;
const float fps = 60.0f;

//---------------------------------------------------------------
//------------------FUNCTIONS------------------------------------
//---------------------------------------------------------------

bool allegro5_setup(        ALLEGRO_DISPLAY **disp,
                            ALLEGRO_EVENT_QUEUE **event_q,
                            ALLEGRO_TIMER **f_timer,
                            ALLEGRO_FONT **font)
{
    if(al_init() == false)
    {
        printf("Allegro did not initialize.\n");
        return false;
    }
    if(al_install_mouse() == false)
    {
        printf("Mouse did not install.\n");
        return false;
    }
    al_set_new_display_option(ALLEGRO_VSYNC, 1, ALLEGRO_SUGGEST);
    *disp = al_create_display(SCREEN_X, SCREEN_Y);
    if(*disp == NULL)
    {
        printf("Display not created.\n");
        return false;
    }
    al_set_window_title(*disp, "Double event loops test");
    *event_q = al_create_event_queue();
    if(*event_q == NULL)
    {
        printf("Event Queue not created.\n");
        al_destroy_display(*disp);
        return false;
    }
    *f_timer = al_create_timer(1.0f / fps);
    if(*f_timer == NULL)
    {
        printf("Timer not created.\n");
        al_destroy_display(*disp);
        al_destroy_event_queue(*event_q);
        return false;
    }

    al_init_font_addon();
    if(al_init_ttf_addon() == false)
    {
        printf("TTF addon not initialized.\n");
        al_destroy_display(*disp);
        al_destroy_event_queue(*event_q);
        al_destroy_timer(*f_timer);
        return false;
    }
    *font = al_load_ttf_font("Verdana.ttf", -20, NULL);
    if(*font == NULL)
    {
        printf("TTF Font did not load. Check that it exists.\n");
        al_destroy_display(*disp);
        al_destroy_event_queue(*event_q);
        al_destroy_timer(*f_timer);
        return false;
    }

    al_register_event_source(*event_q, al_get_display_event_source(*disp));
    al_register_event_source(*event_q, al_get_mouse_event_source());
    al_register_event_source(*event_q, al_get_timer_event_source(*f_timer));
    return true;
}

//---------------------------------------------------------------

void allegro5_terminate(        ALLEGRO_DISPLAY **disp,
                                ALLEGRO_EVENT_QUEUE **event_q,
                                ALLEGRO_TIMER **f_timer,
                                ALLEGRO_FONT **font)
{
    printf("\nAllegro 5.1 Termination accessed\n");
    al_destroy_display(*disp);
    al_destroy_event_queue(*event_q);
    al_destroy_timer(*f_timer);
    al_destroy_font(*font);
}

//---------------------------------------------------------------

//---------------------------------------------------------------

bool print_message(ALLEGRO_FONT *font)
{
    bool second_loop = true;

    ALLEGRO_EVENT_QUEUE *event_queue_2 = NULL;
    event_queue_2 = al_create_event_queue();
    if(event_queue_2 == NULL)
    {
        printf("Event Queue not created.\n");
        return false;
    }

    al_register_event_source(event_queue_2, al_get_mouse_event_source());
    al_clear_to_color(al_map_rgb(100,0,100));
    al_draw_text(font, al_map_rgb(255,255,255), 400.0f, 300.0f, ALLEGRO_ALIGN_CENTER, "HERE'S THE TEST. CLCIK MOUSE TO CONTINUE.");
    al_flip_display();

    while(second_loop == true)
    {
        ALLEGRO_EVENT event_2;
        al_wait_for_event(event_queue_2, &event_2);
        switch(event_2.type)
        {
            case ALLEGRO_EVENT_MOUSE_BUTTON_DOWN:
                second_loop = false;
                break;
            default:
                break;
        }
    }
    al_destroy_event_queue(event_queue_2);
    return true;
}

//---------------------------------------------------------------

bool draw_screen(ALLEGRO_FONT *font)
{
    static int r = 0;
    al_clear_to_color(al_map_rgb(r, 0, 0));
    al_flip_display();
    r++;
    if(r > 255) // When we get maximum red value
    {
        if(print_message(font) == false)
        {
            printf("\nNo, it did not work\n");
            return false;
        }
        r = 0;
    }
    return true;
}


//---------------------------------------------------------------

int main(int argc, char *argv[])
{
    ALLEGRO_DISPLAY *display = NULL;
    ALLEGRO_EVENT_QUEUE *event_queue = NULL;
    ALLEGRO_TIMER *timer = NULL;
    ALLEGRO_FONT *font_1 = NULL;

    bool first_loop = true;
    bool draw = false;

    if(allegro5_setup(&display, &event_queue, &timer, &font_1) == false)
    {
        printf("\nProgram crashed out.\n\n");
        return -1;
    }


    al_start_timer(timer);

    while(first_loop == true)
    {
        ALLEGRO_EVENT event;
        al_wait_for_event(event_queue, &event);

        switch(event.type)
        {
            case ALLEGRO_EVENT_DISPLAY_CLOSE:
                first_loop = false;
                break;
            case ALLEGRO_EVENT_TIMER:
                draw = true;
                break;
            default:
                break;
        }
        if(draw == true && al_event_queue_is_empty(event_queue))
        {
            if(draw_screen(font_1) == false)
                first_loop = false;

            draw = false;
        }
    }

    al_stop_timer(timer);
    allegro5_terminate(&display, &event_queue, &timer, &font_1);
    printf("\nApparently a Normal Termination of the Program was executed.\n\n");
    return 0;
}