#include <cs50.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>


//elements used for the encrypt function
string abcArray = "abcdefghijklmnopqrstuvwxyz";
string ABCArray = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

int encrypt(string text, string argv[]); //encrypt function

int main(int argc, string argv[])
{

    if (argc==2) //check amount of command line arguments
    {
        if (strlen(argv[1])==26) // check amount of characters in the key
        {
            for(int i=0; i<26; i++)
            {
                if((argv[1][i]>=65 && argv[1][i]<=97) || (argv[1][i]>=97 && argv[1][i]<=122)) //check type of character in key
                {
                    for(int p=i+1; p<26; p++) //check repeating letters in key
                    {
                        if ((argv[1][i] != argv[1][p]) && ((argv[1][i]+32) != argv[1][p]) && ((argv[1][i]-32) != argv[1][p]))
                        {

                        }
                        else
                        {
                            printf("The key must not contain the same letter twice\n");
                            return 1;
                        }
                    }
                }
                else
                {
                    printf("Key must only contain alphabetic characters\n");
                    return 1;
                }
            }
        }
        else
        {
            printf("Key must contain 26 characters\n");
            return 1;
        }
    }
    else
    {
        printf("Usage: ./substitution key\n");
        return 1;
    }
    string t = get_string("plaintext: ");
    printf("ciphertext: %c", encrypt(t, argv));
    printf("\n");
    return 0;
}


//encrypt function
int encrypt(string text, string argv[])
{
    for(int x = 0; x <= strlen(text); x++)
    {
        if ((text[x]<65) || (text[x]>90 && text[x]<97) || (text[x]>122))
        {
            printf("%c", text[x]);
        }
        else if ((text[x]>=65) && (text[x]<=90))
        {
            for(int y=0; y<=strlen(ABCArray); y++)
            {
                if(text[x]==ABCArray[y])
                {
                    printf("%c", toupper(argv[1][y]));
                }
            }
        }
        else
        {
            for(int z=0; z<=strlen(abcArray); z++)
            {
                if(text[x]==abcArray[z])
                {
                    printf("%c", tolower(argv[1][z]));
                }
            }
        }
    }
    return 0;
}