#define author "Marek Bielik",
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <ctype.h>
#include "hangman.h"

int is_word_guessed(const char secret[], const char letters_guessed[]){
    int matched=0;
    for (int i=0; i < strlen(letters_guessed); i++) {
      for (int j=0; j < strlen(secret); j++) {
          if (letters_guessed[i]==secret[j]) { matched++; }
      }
    }
    if (matched == strlen(secret)) return 1;
    return 0;
}

void get_guessed_word(const char secret[], const char letters_guessed[], char guessed_word[]){
  int i;
  for (i = 0; i < strlen(secret); i++) {
    if (strchr(letters_guessed, secret[i]) != NULL) guessed_word[i] = secret[i];
    else guessed_word[i] = '_';
  }
  guessed_word[i] = '\0';
  return;
}

void get_available_letters(const char letters_guessed[], char available_letters[]){
  char allLetters[] = "abcdefghijklmnopqrstuvwxyz";
  int n = 0;
  int matched = 0;
  for (int i = 0; i < strlen(allLetters); i++) {
    matched = 0;
    for (int j = 0; j < strlen(letters_guessed); j++) {
      if (allLetters[i] == letters_guessed[j]) { matched = 1; break; }
    }
    if (!matched) {
      available_letters[n] = allLetters[i];
      n++;
    }
  }
  available_letters[n] = '\0';
}

void hangman(const char secret[]){
  if (secret == NULL) { printf("Error: secret is NULL\n"); return; }
  char available_letters[] = "abcdefghijklmnopqrstuvwxyz";
  char guessed_word[24] = "";
  char guessed[24] = "";
  char letters_guessed[26] = "";
  int word_length = strlen(secret);
  int number_of_guesses = 8;

  printf("Welcome to the game, Hangman!\n");
  printf("I am thinking of a word that is %d letters long.\n", word_length);
  while (number_of_guesses > 0) {
    printf("-------------\n");
    if (is_word_guessed(secret, letters_guessed)) {
      printf("Congratulations, you won!\n");
      return;
    }
    printf("You have %d guesses left.\n", number_of_guesses);
    get_available_letters(letters_guessed, available_letters);
    printf("Available letters: %s\n", available_letters);
    printf("Please guess a letter: ");
    scanf("%s", guessed);
    guessed[0] = tolower(guessed[0]);
    if (strlen(guessed) > 1) { //slovo
      if (strcmp(guessed, secret) == 0) {
        printf("Congratulations, you won!\n");
        return;
      } else {
        printf("Sorry, bad guess. The word was %s.\n", secret);
        return;
      }
    } else { //pismeno
      if (strpbrk(available_letters, guessed) != NULL) {
        // printf("letters_guessed before: %s\n", letters_guessed);
        letters_guessed[strlen(letters_guessed)] = guessed[0];
        letters_guessed[strlen(letters_guessed)+1] = '\0';
        // printf("letters_guessed after : %s\n", letters_guessed);
        if (strpbrk(secret, guessed) != NULL) {
          printf("Good guess:");
        } else {
          number_of_guesses--;
          printf("Oops! That letter is not in my word:");
        }
      } else {
        printf("Oops! You've already guessed that letter:");
      }
      get_guessed_word(secret, letters_guessed, guessed_word);
      for (int i = 0; i < strlen(guessed_word); i++) printf(" %c", guessed_word[i]);
      printf("\n");
    }
  }
  printf("-------------\nSorry, you ran out of guesses. The word was %s.\n", secret);
  return;
}

int get_word(char secret[]){
    // check if file exists first and is readable
    FILE *fp = fopen(WORDLIST_FILENAME, "rb");
    if( fp == NULL ){

        fprintf(stderr, "No such file or directory: %s\n", WORDLIST_FILENAME);
        return 1;
    }

    // get the filesize first
    struct stat st;
    stat(WORDLIST_FILENAME, &st);
    long int size = st.st_size;

    do{
        // generate random number between 0 and filesize
        long int random = (rand() % size) + 1;
        // seek to the random position of file
        fseek(fp, random, SEEK_SET);
        // get next word in row ;)
        int result = fscanf(fp, "%*s %20s", secret);
        if( result != EOF )
            break;
    }while(1);


    fclose(fp);

    return 0;
}