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

#include "exercise1_benoit_dardenne.h"

void anagrams(char* dictionary[], int nwords)
{
    StringCouple* table = sortStrings(dictionary, nwords);

    if(table == NULL)
    {
        fprintf(stderr, "Memory allocation failure.\n");
        return;
    }

    qsort(table, nwords, sizeof(StringCouple), compareStrings);
    findAnagrams(table, nwords);
    free(table);
}

StringCouple* sortStrings(char* strings[], size_t count)
{
    StringCouple* table = malloc(count * sizeof(StringCouple));
    if(table == NULL) return NULL;

    char* words = malloc(count * STRING_MAX);
    if(words == NULL)
    {
        free(table);
        return NULL;
    }

    size_t i;
    for(i = 0; i < count; i++)
    {
        table[i].source = strings[i];
        table[i].sorted = words;

        char* tmp = words;

        words = stpcpy(words, strings[i]);

        //Sort the letters
        qsort(tmp, words - tmp, 1, compareChars);
        words++;
    }

    return table;
}

int compareChars(const void* elemA, const void* elemB)
{
    return *(char *) elemA - * (char *) elemB;
}

int compareStrings(const void* elemA, const void* elemB)
{
    return strncmp( ((StringCouple *) elemA)->sorted, ((StringCouple *) elemB)->sorted, STRING_MAX);
}

void findAnagrams(StringCouple table[], size_t count)
{
    bool inGroup = false;
    size_t i;
    for(i = 1; i < count; i++)
    {
        if(strncasecmp(table[i].sorted, table[i - 1].sorted, STRING_MAX) == 0)
        {
            if(!inGroup)
            {
                printf("%s\n", table[i - 1].source);
                inGroup = true;
            }
            printf("%s\n", table[i].source);
        }
        else
        {
            if(inGroup)
                printf("\n");

            inGroup = false;
        }
    }
}