/*
    Copyright (C) 2012-2021 Carl Hetherington <cth@carlh.net>

    This file is part of DCP-o-matic.

    DCP-o-matic 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 2 of the License, or
    (at your option) any later version.

    DCP-o-matic 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 DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.

*/


#include "scp_uploader.h"
#include "exceptions.h"
#include "job.h"
#include "config.h"
#include "cross.h"
#include <dcp/file.h>
#include <dcp/filesystem.h>
#include <dcp/warnings.h>
#include <sys/stat.h>

#include "i18n.h"


using std::function;
using std::min;
using std::shared_ptr;
using std::string;


SCPUploader::SCPUploader(function<void (string)> set_status, function<void (float)> set_progress)
	: Uploader(set_status, set_progress)
{
	_session = ssh_new();
	if (!_session) {
		throw NetworkError(fmt::format(_("SSH error [{}]"), "ssh_new"));
	}

	ssh_options_set(_session, SSH_OPTIONS_HOST, Config::instance()->tms_ip().c_str());
	ssh_options_set(_session, SSH_OPTIONS_USER, Config::instance()->tms_user().c_str());
	int const port = 22;
	ssh_options_set(_session, SSH_OPTIONS_PORT, &port);

	int r = ssh_connect(_session);
	if (r != SSH_OK) {
		throw NetworkError(fmt::format(_("Could not connect to server {} ({})"), Config::instance()->tms_ip(), ssh_get_error(_session)));
	}

LIBDCP_DISABLE_WARNINGS
	r = ssh_is_server_known(_session);
	if (r == SSH_SERVER_ERROR) {
		throw NetworkError(fmt::format(_("SSH error [{}] ({})"), "ssh_is_server_known", ssh_get_error(_session)));
	}
LIBDCP_ENABLE_WARNINGS

	r = ssh_userauth_password(_session, 0, Config::instance()->tms_password().c_str());
	if (r != SSH_AUTH_SUCCESS) {
		throw NetworkError(fmt::format(_("Failed to authenticate with server ({})"), ssh_get_error(_session)));
	}

LIBDCP_DISABLE_WARNINGS
	_scp = ssh_scp_new(_session, SSH_SCP_WRITE | SSH_SCP_RECURSIVE, Config::instance()->tms_path().c_str());
LIBDCP_ENABLE_WARNINGS
	if (!_scp) {
		throw NetworkError(fmt::format(_("SSH error [{}] ({})"), "ssh_scp_new", ssh_get_error(_session)));
	}

LIBDCP_DISABLE_WARNINGS
	r = ssh_scp_init(_scp);
LIBDCP_ENABLE_WARNINGS
	if (r != SSH_OK) {
		throw NetworkError(fmt::format(_("SSH error [{}] ({})"), "ssh_scp_init", ssh_get_error(_session)));
	}
}


SCPUploader::~SCPUploader()
{
LIBDCP_DISABLE_WARNINGS
	ssh_scp_free(_scp);
LIBDCP_ENABLE_WARNINGS
	ssh_disconnect(_session);
	ssh_free(_session);
}


void
SCPUploader::create_directory(boost::filesystem::path directory)
{
	/* Use generic_string so that we get forward-slashes in the path, even on Windows */
LIBDCP_DISABLE_WARNINGS
	int const r = ssh_scp_push_directory(_scp, directory.generic_string().c_str(), S_IRWXU);
LIBDCP_ENABLE_WARNINGS
	if (r != SSH_OK) {
		throw NetworkError(fmt::format(_("Could not create remote directory {} ({})"), directory.string(), ssh_get_error(_session)));
	}
}


void
SCPUploader::upload_file(boost::filesystem::path from, boost::filesystem::path to, boost::uintmax_t& transferred, boost::uintmax_t total_size)
{
	auto to_do = dcp::filesystem::file_size(from);
	/* Use generic_string so that we get forward-slashes in the path, even on Windows */
LIBDCP_DISABLE_WARNINGS
	ssh_scp_push_file(_scp, to.generic_string().c_str(), to_do, S_IRUSR | S_IWUSR);
LIBDCP_ENABLE_WARNINGS

	dcp::File f(from, "rb");
	if (!f) {
		throw NetworkError(fmt::format(_("Could not open {} to send"), from.string()));
	}

	std::vector<char> buffer(64 * 1024);

	while (to_do > 0) {
		int const t = min(to_do, static_cast<uintmax_t>(buffer.size()));
		size_t const read = f.read(buffer.data(), 1, t);
		if (read != size_t(t)) {
			throw ReadFileError(from);
		}

LIBDCP_DISABLE_WARNINGS
		int const r = ssh_scp_write(_scp, buffer.data(), t);
LIBDCP_ENABLE_WARNINGS
		if (r != SSH_OK) {
			throw NetworkError(fmt::format(_("Could not write to remote file ({})"), ssh_get_error(_session)));
		}
		to_do -= t;
		transferred += t;

		if (total_size > 0) {
			_set_progress((double) transferred / total_size);
		}
	}
}