/**
 *--------------------------------------------------------------------\n
 *          HSLU T&A Hochschule Luzern Technik+Architektur            \n
 *--------------------------------------------------------------------\n
 *
 * \brief         ASYD assignment crypto 03
 * \file
 * \author        Basil Estermann, basil.estermann@stud.hslu.ch
 *                Simon Frei, simon.frei@stud.hslu.ch
 *                Jonas Arnold, jonas.arnold@stud.hslu.ch
 * \date          09.03.2023
 *
 *--------------------------------------------------------------------
 */

#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "encryptionArithmetic.h"
#include "DHKE.h"


#define KEY_LENGTH 32

/* filenames as of this code:
 */

void main(void) {

    /* Initialize variables */

    t_encryptionArithmetic P;
    encryptionArithmetic_Init(&P, KEY_LENGTH);
    if (encryptionArithmetic_stringToHex("19", P.number, KEY_LENGTH) == false) {
        printf("ERROR: Creating P.");
        return 1000000;
    }
    
    //t_encryptionArithmetic alpha;
    //encryptionArithmetic_Init(&alpha, KEY_LENGTH);
    //if (encryptionArithmetic_stringToHex("13", alpha.number, KEY_LENGTH) == false) {
    //    printf("ERROR: Creating alpha.");
    //    return 1000001;
    //}

    t_encryptionArithmetic pub;
    encryptionArithmetic_Init(&pub, KEY_LENGTH);
    if (encryptionArithmetic_stringToHex("11", pub.number, KEY_LENGTH) == false) {
        printf("ERROR: Creating pub.");
        return 1000002;
    }

    t_encryptionArithmetic priv;
    encryptionArithmetic_Init(&priv, KEY_LENGTH);
    if (encryptionArithmetic_stringToHex("21", priv.number, KEY_LENGTH) == false) {
        printf("ERROR: Creating priv.");
        return 1000003;
    }

    t_encryptionArithmetic session_key;
    encryptionArithmetic_Init(&session_key, KEY_LENGTH);


    /* Create session key */
    squareAndMultiply(&pub, &priv, &P, &session_key, KEY_LENGTH);


    /* Write session key */
    printf("%i",*session_key.number);


    return 0;
}

//void encrypt(uint32_t key[4], uint8_t numberOfCycles) {
//
//    /* duplicate code that hasn't been moved to a separate function for readability reasons */
//    /* -------------------------------------------------------------------- */
//
//    /* variables */
//    uint32_t amountOfCharsInFile = 0;
//    /* https://www.programiz.com/c-programming/c-file-input-output */
//    FILE* fileHandle = fopen("plaintext.txt", "r");
//    if (fileHandle == NULL) {
//        return;
//    }
//
//    /* get total number of characters in file to encrypt */
//    while (getc(fileHandle) != EOF) {
//        amountOfCharsInFile++;
//    }
//
//    /* allocate enough memory for the whole file to be read */
//    char* inputText = (char*)calloc(amountOfCharsInFile + 8, sizeof(char)); /* add 8 for extra padding in case the file contains some sort of rest in regards to amountOfCharsInFile % 8 */
//    if (inputText == NULL) {
//        return;
//    }
//
//    /* close and reopen file to start at the beginning of the file again */
//    fclose(fileHandle);
//    fileHandle = fopen("plaintext.txt", "r");
//    if (fileHandle == NULL) {
//        return;
//    }
//
//    /* read the whole file into memory */
//    for (uint32_t i = 0; i < amountOfCharsInFile; i++) {
//        inputText[i] = getc(fileHandle);
//    }
//    fclose(fileHandle);
//    /* -------------------------------------------------------------------- */
//
//    /*  loop through the whole array to encrypt the whole message
//        This happens two blocks of 32bit (= 8 characters) at a time
//        Hence the increase of "i" by 8
//    */
//    for (uint32_t i = 0; i < amountOfCharsInFile; i += 8) { /* + 8 to compensate for the requested element size of the encipher function (32 bit) */
//        /* dereferencing and forwarding the address of the key ensures, 
//         * that we don't ready from a random address in memory. Rookie mistakes happen :) */
//        encipher_CBC(numberOfCycles, &(inputText[i]), &(*key));
//    }
//
//    /* generate new file where encryption is stored */
//    fileHandle = fopen("encrypted.cip", "w");
//    if (fileHandle == NULL) {
//        return;
//    }
//    /* fill new file with content */
//    /* to get the extra character padding we might unintentionally drop
//     * we need to read up to a multiple of 8 (32 bit)
//     */
//    for (uint32_t i = 0; i < (amountOfCharsInFile + (8-(amountOfCharsInFile%8))); i++) {
//        putc(inputText[i], fileHandle);
//    }
//    fclose(fileHandle);
//    free(inputText);
//}
//
//void decrypt(uint32_t key[4], uint8_t numberOfCycles) {
//
//    /* duplicate code that hasn't been moved to a separate function for readability reasons */
//    /* -------------------------------------------------------------------- */
//
//    /* variables */
//    uint32_t amountOfCharsInFile = 0;
//
//    /* https://www.programiz.com/c-programming/c-file-input-output */
//    FILE* fileHandle = fopen("encrypted.cip", "r");
//    if (fileHandle == NULL) {
//        return;
//    }
//
//    /* get total number of characters in file to decrypt */
//    while (getc(fileHandle) != EOF) {
//        amountOfCharsInFile++;
//    }
//
//    /* allocate memory for the whole file to be read */
//    char* inputText = (char*)calloc(amountOfCharsInFile + 10, sizeof(char)); /* add 10 for extra padding */
//    if (inputText == NULL) {
//        return;
//    }
//
//    /* close and reopen file to start at the beginning of the file again */
//    fclose(fileHandle);
//    fileHandle = fopen("encrypted.cip", "r");
//    if (fileHandle == NULL) {
//        return;
//    }
//
//    /* read the whole file into memory */
//    for (uint32_t i = 0; i < amountOfCharsInFile; i++) {
//        inputText[i] = getc(fileHandle);
//    }
//    fclose(fileHandle);
//
//    /* -------------------------------------------------------------------- */
//
//    /*  loop through the whole array to encrypt the whole message
//        This happens two blocks of 32bit (= 4 characters) at a time
//        Hence the increase of "i" by 8
//    */
//
//    for (uint32_t i = 0; i < amountOfCharsInFile; i += 8) { /* i += 8*/
//        /* dereferencing and forwarding the address of the key ensures,
//         * that we don't ready from a random address in memory. Rookie mistakes happen :) */
//        decipher_CBC(numberOfCycles, &(inputText[i]), &(*key));
//    }
//
//    /* generate new file where the decryption is stored */
//    fileHandle = fopen("decrypted.txt", "w");
//    if (fileHandle == NULL) {
//        return;
//    }
//    /* fill new file with content */
//    for (uint32_t i = 0; i < amountOfCharsInFile; i++) {
//        putc(inputText[i], fileHandle);
//    }
//    fclose(fileHandle);
//    free(inputText);
//}