#define _GNU_SOURCE

#include "encryption.h"
#include "shared.h"

#include <sodium.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <stdarg.h>
#include <unistd.h>
#include <errno.h>
#include <error.h>
#include <fcntl.h>
#include <stdio.h>

int checkSodium(void) {
    int ret = sodium_init();
    if(ret < 0)
        error(1, ENOTSUP, "Couldn't initialize sodium for some reason. Quitting...");

    return ret;
}

// To encrypt:
// 1- Create a temp file with the correct name in the root folder of the partition being encrypted      -- 
    // 1.1- Detect the partition and find the root folder                                                   -- DONE || NOT NECESSARY
    // 1.2- Create the temp file                                                                            -- DONE
// 2- Encrypt the file's contents to the temp file                                                      -- 
    // 2.1- Open the file                                                                                   -- 
    // 2.2- Stream the file's contents into some encryption algo                                            -- 
    // 2.3- Pipe the output of the encryption into the temp file                                            -- 
// 3- Once the file has been encrypted, hard link it back to the original location, with the right name -- 
// 4- Delete the original file                                                                          -- 
// 5- Delete the temp file                                                                              --


int maketmp(const char *dest) {
    return open(dest, (O_TMPFILE | O_WRONLY | O_CLOEXEC | O_SYNC), (S_IRUSR | S_IWUSR));
}

int encrypttotmp(const char *toencrypt) {
    struct stat esb;
    int efd = -1;

    // Make sure the file is real and an actual file that can be encrypted
    if(stat(toencrypt, &esb) < 0)
        return -1;
    if(!S_ISREG(esb.st_mode))
        return -2;

    // Open the file as read-only
    if((efd = open(toencrypt, O_RDONLY)) < 0)
        return -3;

    // Need to get a secret key from a password and then set up cryptostream from libsodium

    return 0;
}

#define TESTING
#ifdef TESTING

#include <string.h>

int main(void) {
    const char *dir = ".", *testmsg = "we do a little testing\n";
    char *path = NULL;

    int fd = maketmp(dir);
    if(fd < 0)
        error(1, errno, "Couldn't make temp file at %s", dir);

    if(write(fd, testmsg, strlen(testmsg)) < 0)
        error(1, errno, "write broke");
    
    asprintf(&path, "/proc/self/fd/%d", fd);
    linkat(AT_FDCWD, path, AT_FDCWD, "./test", AT_SYMLINK_FOLLOW);
    free(path);

    // Apparently, I don't have the CAP_DAC_READ_SEARCH capibility. Thanks for the solution, linux man pages

    if(close(fd) < 0)
        error(1, errno, "close broke");

    return 0;
}

#endif