/* --------------------------------------------------------------------- 
**  Figure 13.21: Selecting ice cream from a menu.
**  Figure 13.22: A menu-handling function.
** --------------------------------------------------------------------- 
*/
#include "tools.h"             /* contains definition of type string */

#define CHOICES  6
int menu ( string title, int max, string menu_list[] );                                                     

void main( void )
{   
    int choice;                                      /* The menu selection */
    string greeting = "\n I'm happy to serve you.  Our specials today are: ";
    string flavor[CHOICES] = { "Empty", "Vanilla", "Pistachio", 
                               "Rocky Road", "Fudge Chip", "Lemon" };
    float price[CHOICES] = { 0.00, 1.00, 1.50, 1.35, 1.25, 1.20 };
    
    choice = menu( greeting, CHOICES, flavor );
    printf( "\n Here is your %s cone.  That will be $%.2f. \n", 
            flavor[choice], price[choice] );
    puts( " Thank you, come again. \n" );
}

/* ---------------------------------------------------------------------- */
/* Display a menu then read and validate a numeric menu choice.           */
int 
menu ( string title, int max, string menu_list[] )                                                      
{
    int choice;                 /* To store the menu selection. */ 
    int n = 0;                  /* Loop counter for menu display. */  

    printf( "\n %s\n", title ); 
    for (n=0; n < max; ++n)  printf( "\t %i. %s \n", n, menu_list[n] );

    printf( " Please enter your selection: "); 
    for(;;) {                  /* Prompt for and validate a menu selection. */ 
        scanf( "%i", &choice ); 
        if (choice >= 0 && choice < max) break;     /* Accept valid choice. */ 
        printf( " Please enter number between 0 and %i: ", max-1 ); 
    } 
    return choice;
}