#include <stdbool.h>
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include "dictionary.h"

// declaring trie structure
typedef struct trie
{
    bool is_word;
    struct trie* letters[27];
} trie;

trie* head;

/**
 * Loads dictionary into memory.  Returns true if successful else false.
 */
bool load(const char* dictionary)
{

    //declaring first node of the trie and pointing in to NULL
    head = (struct trie*)malloc(sizeof(trie));

    //declare word count for the number of words loaded to the dictionary
    int words = 0;

    //set all root node pointers to null
    for (int i = 0; i < 27; i++)
    {
        head->letters[i] = NULL;
    }

    // open dictionary file  ==> need to set the cursor at the beginning of the file each time
    FILE* inptr = fopen(dictionary, "r");
    if (inptr == NULL)
    {
        printf("Could not open %s.\n", dictionary);
        return 2;
    }

    //declare new trie to jump thru characters
    trie* current = head;

    //go thru each character in the file until end of file
    for (int i = 0, ch = 1; ch != EOF; i++)
    {
        //read the current character from file
        ch = fgetc(inptr);

        // if the character is a letter or an apostrophe
        if (ch != '\n')
        {
            //if the pointer for the character doesn't exist (equals NULL) allocate memory
            if (current->letters[tolower(ch) - 'a'] == NULL)
            {
                current->letters[tolower(ch) - 'a'] = (struct trie*)malloc(sizeof(trie));
            }

            //move forward in our trie structure
            current = current->letters[tolower(ch) - 'a'];
        }

        //if the character read indicates the end of the line
        else
        {
            //indicate that this is a word in our dictionary in the trie
            current->is_word = true;
            //reset our current node to the beginning of the trie
            current = head;
            //count number of words loaded in the dictionary
            words++;
        }
    }

    printf ("%i words loaded to the dictionary\n", words);

    // close infile
    fclose(inptr);

    return true;
}