/*
 * Shows user info from local pwfile.
 *
 * Usage: userinfo username
 */

#define _XOPEN_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdbool.h>
#include "pwdblib.h"   /* include header declarations for pwdblib.c */

/* Define some constants. */
#define USERNAME_SIZE (32)
#define PASSWORD_SIZE (32)
#define NOUSER (-1)


int print_info(const char *username)
{
  struct pwdb_passwd *p = pwdb_getpwnam(username);
  if (p != NULL) {
    printf("Name: %s\n", p->pw_name);
    printf("Passwd: %s\n", p->pw_passwd);
    printf("Uid: %u\n", p->pw_uid);
    printf("Gid: %u\n", p->pw_gid);
    printf("Real name: %s\n", p->pw_gecos);
    printf("Home dir: %s\n",p->pw_dir);
    printf("Shell: %s\n", p->pw_shell);
    return 0;
  } else {
    return NOUSER;
  }
}

void read_username(char *username)
{
  printf("login: ");
  fgets(username, USERNAME_SIZE, stdin);

  /* remove the newline included by getline() */
  username[strlen(username) - 1] = '\0';
}

void read_password(char *password)
{
    strcpy(password, getpass("Enter password: "));
}

void checkPassword(char *realPassword, const char *username)
{
  struct pwdb_passwd *p = pwdb_getpwnam(username);
  if (p != NULL) {
      strcpy(realPassword, p->pw_passwd);
  }
}

void increaseSuccessfulLogin(const char *username){
    struct pwdb_passwd *p = pwdb_getpwnam(username);
    if (p != NULL) {
      int oldValue = p->pw_age;
      printf("old value: %i \n", oldValue);
      int newValue = oldValue + 1;
      if (newValue > 10) {
      printf("Your password is old, it is recommended that you update it! \n");
    }
      p->pw_age = newValue;
      pwdb_update_user(p);
    }
}

void increaseFailedLogin(const char *username){
    struct pwdb_passwd *p = pwdb_getpwnam(username);
      if (p != NULL) {
        int oldValue = p->pw_failed;
        int newValue = oldValue + 1;
        p->pw_failed = newValue;
        pwdb_update_user(p);
      }
}

void zeroFails(const char *username){
    struct pwdb_passwd *p = pwdb_getpwnam(username);
    if (p != NULL) {
      int newValue = 0;
      p->pw_failed = newValue;
      pwdb_update_user(p);
    }
}

bool isLockedOut(const char *username){
    struct pwdb_passwd *p = pwdb_getpwnam(username);
    if (p != NULL) {
      int failedLogins = p->pw_failed;
      return failedLogins >= 5;
    }
}

char* concat(const char *s1, const char *s2)
{
    char *result = malloc(strlen(s1) + strlen(s2) + 1); // +1 for the null-terminator
    // in real code you would check for errors in malloc here
    strcpy(result, s1);
    strcat(result, s2);
    return result;
}

int main(int argc, char **argv)
{


  while(1) {

   char username[USERNAME_SIZE];
   char password[PASSWORD_SIZE];
   char realPassword[PASSWORD_SIZE];

  /*
   * Write "login: " and read user input. Copies the username to the
   * username variable.
   */
   read_username(username);
   read_password(password);

   if (isLockedOut(username)) {
   printf("Too many unsuccessful login attempts. Please contact admin.\n");
   return 0;
   }

   checkPassword(realPassword, username);

     if (realPassword!=NULL) {

         char salt[2];
         salt[0] = realPassword[0];
         salt[1] = realPassword[1];
         const char *saltConst = salt;
         const char *passwordConst = password;
         const char *cryptedPw = crypt(passwordConst, saltConst);
         const char *saltAndCryptedPassword = concat(salt, cryptedPw); // username changes somewhere in this if-statement!
          if (strcmp(realPassword,cryptedPw) == 0) {
             increaseSuccessfulLogin(username);
             zeroFails(username);
             printf("User authenticated successfully\n");
             return 0;
          }
     }

     increaseFailedLogin(username);
     printf("Unknown user or incorrect password. \n");
  }
  /* Show user info from our local pwfile.
   if (print_info(username) == NOUSER) {
      /* if there are no user with that usename...
      printf("\nFound no user with name: %s\n", username);
      return 0;
  } */
}