/*
 * The Actual Pig Latin Word Making function
 *
 * This function takes a word (all letters terminated
 * with a NULL) and converts it into Pig Latin following
 * some made-up rules. The word is stored in the
 * piglatin[] buffer. Various string routines copy and
 * concatenate parts of the re-constructed word into
 * that buffer. The original starting letter is also
 * saved in a buffer, append[], since only strings can
 * be concatenated to each other, not single chars.
 *
 * A pointer variable saves the original address of the
 * word being translated, so the word is send and
 * returned as the same variable. This saves going
 * through the pains of returning a string from a
 * function.
 */

#include <stdio.h>
#include <ctype.h>
#include <string.h>

void iglatinpay(char *english)
{
    char piglatin[32];      //temporary word sto.
    char *e;
    char append[] = "h";    //first letter sto.
    char ch;

/*
 * Start by saving the starting address of the word
 * being sent to this function. The E pointer variable
 * will remember that for you.
 */

    e = english;

/*
 * All Pig Latin is written lower case with initial
 * caps. (At least that's the easy way to handle
 * things here.)
 */

    strlwr(english);        //make it all lower case

/*
 * RULES FOR TRANSLATING ENGLISH INTO PIG LATIN
 * As told to a switch-case loop
 *
 * First rule: Words starting with a vowel
 * are merely given the AY ending.
 *
 * Note how strcpy() is used first, then strcat()
 * is used to continue building the Pig Latin word
 *
 * Also: See how the case statements "fall through,"
 * allowing several of them to catch common
 * situations.
 */

    ch = *english;          //save the first character
    switch(ch)
    {
        case 'a':
        case 'e':
        case 'i':
        case 'o':
        case 'u':
            strcpy(piglatin,english);
            strcat(piglatin,"ay");
            break;

/*
 * Second rule: Words starting with SH, CH
 * TH, PH, RH, WH, QU have both letters moved
 * to the end before adding AY
 */

                    //continuing switch-case
        case 'c':
        case 'p':
        case 'r':
        case 's':
        case 't':
        case 'w':
            if(english[1]=='h')
            {
                english+=2;     //point at 3rd char
                                // after ?H sound
                strcpy(piglatin,english);
                                //add on the starting letter
                append[0] = ch;
                strcat(piglatin,append);
                                //and then the 'H' and "AY"
                strcat(piglatin,"hay");
                break;
            }
        case 'q':
            if(english[1]=='u')
            {
                english+=2;
                strcpy(piglatin,english);
                append[0] = ch;
                strcat(piglatin,append);
                strcat(piglatin,"uay");
                break;
            }

/*
 * Standard rule: Move the first letter to the
 * end of the word and add AY
 */
                    //continuing switch-case
        default:
            english++;
            strcpy(piglatin,english);
            append[0] = ch;
            strcat(piglatin,append);
            strcat(piglatin,"ay");
            break;
    }

/*
 * To "return" the word to the calling function
 * you'll simply copy the word you constructed (which
 * is in the piglatin[] buffer) to the location of the
 * word being translated, which was saved in the E
 * pointer.
 */

    strcpy(e,piglatin);

/*
 * And finally, make the initial cap of each word
 */

    *e = toupper(*e);
}