/*
 * Yorkie - A task-oriented GnuPG frontend
 * Copyright (C) 2020 Damien Goutte-Gattat
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "gpgutil.h"

#include <stdio.h>
#include <errno.h>
#include <locale.h>

#include "error.h"


gpgme_ctx_t
gpgutil_initialize(GError **error)
{
    gpgme_ctx_t ctx = NULL;
    gpgme_error_t gerr;

    gpgme_check_version(NULL);
    gpgme_set_locale(NULL, LC_CTYPE, setlocale(LC_CTYPE, NULL));
    gpgme_set_locale(NULL, LC_MESSAGES, setlocale(LC_MESSAGES, NULL));

    if ( (gerr = gpgme_new(&ctx)) )
        yki_error_gpgme(error, YKI_ERROR_GPGME_INTERNAL, gerr);

    return ctx;
}

int
gpgutil_open_file(const char       *name,
                  const char       *mode,
                  gpgutil_file_t   *file,
                  GError          **error)
{
    gpgme_error_t gerr;

    g_assert(file);

    gerr = 0;
    file->buffer = NULL;
    file->file = NULL;

    if ( name )
        file->file = fopen(name, mode);
    else
        file->file = tmpfile();
    if ( ! file )
        gerr = gpgme_error_from_errno(errno);

    if ( ! gerr )
        gerr = gpgme_data_new_from_stream(&file->buffer, file->file);

    if ( ! gerr && name )
        gerr = gpgme_data_set_file_name(file->buffer, name);

    if ( gerr ) {
        if ( file->buffer ) {
            gpgme_data_release(file->buffer);
            file->buffer = NULL;
        }

        if ( file->file ) {
            fclose(file->file);
            file->file = NULL;
        }

        yki_error_gpgme(error, YKI_ERROR_GPGME_OPEN, gerr);
    }

    return gpgme_err_code(gerr) == 0;
}


int
gpgutil_close_file(gpgutil_file_t *file, GError **error)
{
    gpgme_error_t gerr = 0;

    g_assert(file);

    if ( file->buffer ) {
        gpgme_data_release(file->buffer);
        file->buffer = NULL;

        if ( fclose(file->file) )
            gerr = gpgme_error_from_errno(errno);
        file->file = NULL;
    }

    if ( gerr )
        yki_error_gpgme(error, YKI_ERROR_GPGME_CLOSE, gerr);

    return gpgme_err_code(gerr) == 0;
}

int
gpgutil_copy_buffer(gpgutil_file_t *src, const char *filename, GError **error)
{
    int ret;
    gpgme_error_t gerr;
    gpgutil_file_t dest = { 0 };

    ret = gpgme_data_seek(src->buffer, 0, SEEK_SET) != -1;

    if ( ret )
        ret = gpgutil_open_file(filename, "w", &dest, error);

    if ( ret ) {
        char buffer[512];
        size_t len;

        while ( ret && (len = gpgme_data_read(src->buffer, buffer, sizeof(buffer))) > 0 )
            ret = gpgme_data_write(dest.buffer, buffer, len);

        if ( ret )
            ret = len != -1;
    }

    if ( ! ret )
        yki_error(error, YKI_ERROR_IO, "Cannot copy data to file: %s", strerror(errno));

    gpgutil_close_file(&dest, NULL);

    return ret;
}