Mouse area detect

/*
Mouse area select
API: Allegro 5.1
KeithS
June 2012
*/
#include <allegro5/allegro.h>
#include <allegro5/allegro_primitives.h>
#include <allegro5/allegro_font.h>
#include <allegro5/allegro_ttf.h>
#include <cstdio>
#include <string>


using namespace std;

const int SCREEN_X = 800;
const int SCREEN_Y = 600;
const float fps = 20.0f;

struct mouse_area
{
    float x1;
    float y1;
    float x2;
    float y2;
    string label;
};

//------------------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;
    }
    *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("../../fonts/Verdana.ttf", -20, NULL);
    if(*font == NULL)
    {
        printf("TTF Font did not load. Check that it exists in /font.\n");
        al_destroy_display(*disp);
        al_destroy_event_queue(*event_q);
        al_destroy_timer(*f_timer);
        return false;
    }
    if(al_init_primitives_addon() == false)
    {
        printf("Primitives did not initialize.\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)
{
    al_destroy_display(*disp);
    al_destroy_event_queue(*event_q);
    al_destroy_timer(*f_timer);
}

//---------------------------------------------------------------
void set_click_areas(mouse_area *clk_ar, int SIZE)
{
    float h_offset = 10.0f;
    float v_offset = 10.0f;
    float h_width = 250.0f;
    float v_height = 23.0f;
    char buffer[100];
    int i;

    for(i = 0; i < SIZE; i++)
    {
        clk_ar[i].x1 = h_offset;
        clk_ar[i].y1 = (i * 25.0f) + v_offset;
        clk_ar[i].x2 = h_offset + h_width;
        clk_ar[i].y2 = (i * 25.0f) + v_offset + v_height;
        sprintf(buffer, "Label %i", i);
        clk_ar[i].label.assign(buffer);
    }

}
//---------------------------------------------------------------
int detect_click(mouse_area *clk_ar, int SIZE, int mx, int my)
{
    int i;
    for(i = 0; i < SIZE; i++)
    {
        if(mx > clk_ar[i].x1 && my > clk_ar[i].y1 && mx < clk_ar[i].x2 && my < clk_ar[i].y2)
            return i;
    }
    return -1;
}
//---------------------------------------------------------------
void draw_click_areas(mouse_area *clk_ar, int SIZE, int sel_ar, ALLEGRO_FONT *font)
{
    ALLEGRO_COLOR select_color = al_map_rgb(250,50,50);
    ALLEGRO_COLOR deselect_color = al_map_rgb(150,150,150);
    ALLEGRO_COLOR color = deselect_color;

    al_clear_to_color(al_map_rgb(0,0,30));

    int i;
    for(i = 0; i < SIZE; i++)
    {
        if(i == sel_ar)
            color = select_color;
        else
            color = deselect_color;

        al_draw_text(font, color, clk_ar[i].x1 + 3.0f, clk_ar[i].y1, ALLEGRO_ALIGN_LEFT, clk_ar[i].label.c_str());
        al_draw_rectangle(clk_ar[i].x1, clk_ar[i].y1, clk_ar[i].x2, clk_ar[i].y2, color, 0);
    }
}
//---------------------------------------------------------------

//---------------------------------------------------------------
//--------------------------MAIN---------------------------------
//---------------------------------------------------------------

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 draw = false;
    bool loop = true;
    bool mouse_b = false;
    int m_x = 0;
    int m_y = 0;
    int M_AREAS = 10;
    int selected_area = -1;

    mouse_area click_area[M_AREAS];
    set_click_areas(click_area, M_AREAS);

    if(allegro5_setup(&display, &event_queue, &timer, &font_1) == false)
        return -1;

    al_start_timer(timer);

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

        switch(event.type)
        {
            case ALLEGRO_EVENT_DISPLAY_CLOSE:
                loop = false;
                break;
            case ALLEGRO_EVENT_MOUSE_BUTTON_DOWN:
                m_x = event.mouse.x;
                m_y = event.mouse.y;
                mouse_b = true;
                selected_area = detect_click(click_area, M_AREAS, m_x, m_y);
                break;
            case ALLEGRO_EVENT_MOUSE_BUTTON_UP:
                mouse_b = false;
                break;
            case ALLEGRO_EVENT_TIMER:
                draw = true;
                break;
            default:
                break;
        }
        if(draw == true && al_event_queue_is_empty(event_queue))
        {
            draw_click_areas(click_area, M_AREAS, selected_area, font_1);
            al_flip_display();
            draw = false;
        }
    }

    return 0;
}