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

typedef struct list_item
{
	char *value;
	struct list_item *next;

}list_item;

void print_help()
{
	printf("Program sluzy do sprawdzania wystapien wrostka w pliku tekstowym.\n");
	printf("Jako argumenty nalezy podac nazwe pliku o rozszerzeniu .txt i tekst wrostka.\n");
	printf("Wrostek i slowa w pliku tekstowym musza skladac sie w pelni z wartosci alfabetycznych.\n");
	printf("Podanie nieprawidlowych parametrow skutkuje wyswietleniem tej wiadomosci i zamknieciem programu.\n\n");
}

int is_alphabetical(char* string)
{
	int i;
	for (i = 0; i<strlen(string); i++)
	{
		if ((string[i] < 'A') || (string[i] > 'Z' && string[i] < 'a') || (string[i] > 'z'))
		{
			return 0;
		}
	}
	return 1;
}

list_item* create_item(char* string)
{
	list_item* new_item = malloc(sizeof(list_item));
	new_item->value = string;
	new_item->next = 0;
	return new_item;
}

void add_to_list(list_item** item, char* string)
{
	list_item *ptr, *new_item = create_item(string);

	//Jesli lista nie jest pusta
	if (*item)
	{
		ptr = *item;
		//Przejdz do konca listy
		while (ptr->next)
		{
			ptr = ptr->next;
		}
		//Dodaj element na koncu listy
		ptr->next = new_item;
	}
	else
	{
		//Dodaj pierwszy element listy
		*item = new_item;
	}
}

char* cut_string(char *input)
{
	char* output = (char*)malloc((strlen(input) + 1)*sizeof(char));
	strcpy(output, input);

	output += 1;
	output[strlen(output) - 1] = '\0';

	return output;
}

int* count_substrings(char* base, char* substring)
{

	//Pierwsza pozycja zawiera ilosc wrostkow, kolejne ich pozycje
	int* results = (int*)malloc(sizeof(int));
	const char *tmp_base = base;
	int count = 0;
	while (tmp_base == strstr(tmp_base, substring))
	{
		count++;
		void *tmp = realloc(results, (count + sizeof(int)));
		if (!tmp)
		{
			return 0;
		}
		else
		{
			results = tmp;
		}
		results[count] = tmp_base - base;
		tmp_base += strlen(substring);
	}
	results[0] = count;
	return results;
}

char* cut_string_length(char* input, int pos, int length)
{
    int i;
    char* output = (char*)malloc((length+1)*sizeof(char));
    for(i = 0; i < length; i++)
    {
        output[i] = input[pos];
        pos++;
    }
    output[length] = 0;
    return output;
}

char* load_string_from_file(char* filename)
{
    FILE *file = fopen(filename, "rb");
    fseek(file, 0, SEEK_END);
    long fsize = ftell(file);
    rewind(file);

    char *response = malloc(fsize + 1);
    fread(response, fsize, 1, file);
    fclose(file);

    response[fsize] = 0;

    return response;
}

list_item* load_list_from_string(char* string)
{
    list_item* item;
    char* word;
    int count = strlen(string);
    int word_length = 0, word_count = 0, i;
    for(i = 0; i < count; i++)
    {
        if ((string[i] <= 'z' && string[i] >= 'a') || (string[i] <= 'Z' && string[i] >= 'A'))
        {
            word_length++;
        }
        else if (word_length > 0)
        {
            if(word_count == 0)
            {
                item = malloc(sizeof(list_item));

            }
            else
            {
                word = cut_string_length(string, i, word_length);
                add_to_list(&item, word);
                printf("%s", word);
            }
            word_count++;
            word_length = 0;
        }
    }
    return item;
}

int main(int argc, char* argv[])
{
	int flag_help = 0, flag_error = 0, arg_file = 0, arg_text = 0, arg_help = 0, i = 0;

	//Znajdz parametry - moga byc podane w dowolnej kolejnosci
	//Pomin pierwszy parametr - nazwe pliku
	for (i = 1; i < argc; i++)
	{
		if (strstr(argv[i], ".txt")) arg_file = i;
		if (strstr(argv[i], "-h"))
		{
			arg_help = i;
			flag_help = 1;
		}
		if (arg_text == arg_file || arg_text == arg_help) arg_text++;
	}

	if ((arg_help + arg_file) == 0) flag_error = 1;
	while (arg_text < argc)
	{
		if (!is_alphabetical(argv[arg_text]))
		{
			arg_text++;
			flag_error = 1;
		}
		else
		{
			flag_error = 0;
			break;
		}
	}

	if (flag_error)
	{
		print_help();
		return 0;
	}

	if (flag_help) print_help();

	printf("Nazwa pliku : %s\n", argv[arg_file]);
	printf("Poszukiwany wrostek : %s\n\n", argv[arg_text]);
	printf("Nacisnij Enter, aby potwierdzic.\n");

	if (getchar() == 10)
	{
		//Wybrano enter, wykonaj operacje
		//list_item *strings_to_scan = load_list_from_file(argv[arg_file]);
		char* text = load_string_from_file(argv[arg_file]);
		if (text)
		{
		    list_item* item = load_list_from_string(text);
		    free(text);
		}
		printf("\n\nNacisnij dowolny przycisk, aby zakonczyc dzialanie programu.");
	}
	else
	{
		return 0;
	}
}