/*
 * Copyright (C) 2014-2021 CZ.NIC
 *
 * 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/>.
 *
 * In addition, as a special exception, the copyright holders give
 * permission to link the code of portions of this program with the
 * OpenSSL library under certain conditions as described in each
 * individual source file, and distribute linked combinations including
 * the two.
 */

#if defined(__APPLE__) || defined(__clang__)
#  define __USE_C99_MATH
#  define _Bool bool
#else /* !__APPLE__ */
#  include <cstdbool>
#endif /* __APPLE__ */

#include <cstdlib> /* ::std::free */
#include <libdatovka/isds.h>
#include <QMutexLocker>

#include "src/datovka_shared/isds/error.h"
#include "src/datovka_shared/isds/message_interface.h"
#include "src/isds/error_conversion.h"
#include "src/isds/message_conversion.h"
#include "src/isds/services.h"
#include "src/isds/services_internal.h"
#include "src/isds/session.h"

namespace Isds {

	/*!
	 * @brief Encapsulates private services.
	 */
	class ServicePrivate {
		Q_DECLARE_TR_FUNCTIONS(ServicePrivate)

	private:
		/*!
		 * @brief Private constructor.
		 */
		ServicePrivate(void);

	public:
		/*!
		 * @brief Functions downloading message list.
		 */
		typedef isds_error (*isdsMessageListGetterFunc)(
		    struct isds_ctx *, const struct isds_timeval *,
		    const struct isds_timeval *, const long int *,
		    const unsigned int, const unsigned long int,
		    unsigned long int *, struct isds_list **);

		/*!
		 * @brief Serves as indexes for accessing message list getter functions.
		 */
		enum MessageListGetter {
			MLG_RECEIVED = 0,
			MLG_SENT = 1
		};

		/*!
		 * @brief Returns a pointer to a message list getter function.
		 *
		 * @param[in] mlg Service identifier.
		 * @return Function pointer.
		 */
		static
		isdsMessageListGetterFunc messageListGetterFunc(
		    enum MessageListGetter mlg)
		{
			static isdsMessageListGetterFunc funcArray[] = {
				isds_get_list_of_received_messages,
				isds_get_list_of_sent_messages
			};

			return funcArray[mlg];
		}

		/*!
		 * @brief Calls message getter services.
		 *
		 * @param[in]     mlg Service identifier.
		 * @param[in,out] ctx Communication context.
		 * @param[in]     dmStatusFilter Status filter, MFS_ANY for all.
		 * @param[in]     dmOffset Sequence number of first requested record.
		 * @param[in,out] dmLimit Message list length limit.
		 * @param[out]    messages Message list.
		 * @return Error description.
		 */
		static
		Error messageListGetterService(enum MessageListGetter mlg,
		    Session *ctx, Type::DmFiltStates dmStatusFilter,
		    unsigned long int dmOffset, unsigned long int *dmLimit,
		    QList<Message> &messages);

		/*!
		 * @brief Functions reading message identifier and returning message.
		 */
		typedef isds_error (*isdsMessageGetterFunc)(struct isds_ctx *, const char *, struct isds_message **);

		/*!
		 * @brief Serves as indexes for accessing message getter functions.
		 */
		enum MessageGetter {
			MG_SIGNED_DELIVERY_INFO = 0,
			MG_SIGNED_RECEIVED_MESSAGE = 1,
			MG_SIGNED_SENT_MESSAGE = 2
		};

		/*!
		 * @brief Returns a pointer to a message getter function.
		 *
		 * @param[in] mg Service identifier.
		 * @return Function pointer.
		 */
		static
		isdsMessageGetterFunc messageGetterFunc(enum MessageGetter mg)
		{
			static isdsMessageGetterFunc funcArray[] = {
				isds_get_signed_delivery_info,
				isds_get_signed_received_message,
				isds_get_signed_sent_message
			};

			return funcArray[mg];
		}

		/*!
		 * @brief Calls message getter services.
		 *
		 * @param[in]     mg Service identifier.
		 * @param[in,out] ctx Communication context.
		 * @param[in]     dmId Message identifier.
		 * @param[out]    message Signed delivery info.
		 * @return Error description.
		 */
		static
		Error messageGetterService(enum MessageGetter mg,
		    Session *ctx, qint64 dmId, Message &message);
	};

}

/*!
 * @brief Converts message filter state.
 */
static
int dmFiltState2libisdsMessageStatus(Isds::Type::DmFiltStates fs)
{
	return (int)fs;
}

Isds::Error Isds::ServicePrivate::messageListGetterService(
    enum MessageListGetter mlg, Session *ctx, Type::DmFiltStates dmStatusFilter,
    unsigned long int dmOffset, unsigned long int *dmLimit,
    QList<Message> &messages)
{
	Error err;

	if (Q_UNLIKELY(ctx == Q_NULLPTR)) {
		Q_ASSERT(0);
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Insufficient input."));
		return err;
	}

	struct isds_list *msgList = NULL;
	bool ok = true;

	{
		QMutexLocker locker(ctx->mutex());

		isds_error ret = messageListGetterFunc(mlg)(ctx->ctx(), NULL,
		    NULL, NULL, dmFiltState2libisdsMessageStatus(dmStatusFilter),
		    dmOffset, dmLimit, &msgList);
		if (Q_UNLIKELY(ret != IE_SUCCESS)) {
			err.setCode(libisds2Error(ret));
			err.setLongDescr(IsdsInternal::isdsLongMessage(ctx->ctx()));
			goto fail;
		}
	}

	messages = (msgList != NULL) ?
	    libisds2messageList(msgList, &ok) : QList<Message>();

	if (ok) {
		err.setCode(Type::ERR_SUCCESS);
	} else {
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Error converting types."));
	}

fail:
	if (msgList != NULL) {
		isds_list_free(&msgList);
	}

	return err;
}

Isds::Error Isds::ServicePrivate::messageGetterService(enum MessageGetter mg,
    Session *ctx, qint64 dmId, Message &message)
{
	Error err;

	if (Q_UNLIKELY((ctx == Q_NULLPTR) || (dmId < 0))) {
		Q_ASSERT(0);
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Insufficient input."));
		return err;
	}

	struct isds_message *msg = NULL;
	bool ok = true;

	{
		QMutexLocker locker(ctx->mutex());

		isds_error ret = messageGetterFunc(mg)(ctx->ctx(),
		    QString::number(dmId).toUtf8().constData(), &msg);
		if (Q_UNLIKELY(ret != IE_SUCCESS)) {
			err.setCode(libisds2Error(ret));
			err.setLongDescr(IsdsInternal::isdsLongMessage(ctx->ctx()));
			goto fail;
		}
	}

	message = (msg != NULL) ? libisds2message(msg, &ok) : Message();

	if (ok) {
		err.setCode(Type::ERR_SUCCESS);
	} else {
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Error converting types."));
	}

fail:
	if (msg != NULL) {
		isds_message_free(&msg);
	}

	return err;
}

Isds::Error Isds::Service::authenticateMessage(Session *ctx,
    const QByteArray &raw)
{
	Error err;

	if (Q_UNLIKELY((ctx == Q_NULLPTR) || raw.isEmpty())) {
		Q_ASSERT(0);
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Insufficient input."));
		return err;
	}

	{
		QMutexLocker locker(ctx->mutex());

		isds_error ret = isds_authenticate_message(ctx->ctx(),
		    raw.constData(), raw.size());
		if (Q_UNLIKELY(ret != IE_SUCCESS)) {
			err.setCode(libisds2Error(ret));
			err.setLongDescr(IsdsInternal::isdsLongMessage(ctx->ctx()));
			return err;
		}
	}

	err.setCode(Type::ERR_SUCCESS);
	return err;
}

Isds::Error Isds::Service::createMessage(Session *ctx, const Message &message,
    qint64 &dmId)
{
	Error err;

	if (Q_UNLIKELY((ctx == Q_NULLPTR) || message.isNull())) {
		Q_ASSERT(0);
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Insufficient input."));
		return err;
	}

	bool ok = false;
	isds_error ret = IE_SUCCESS;
	struct isds_message *msg = message2libisds(message, &ok);
	if (Q_UNLIKELY(!ok)) {
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Error converting types."));
		goto fail;
	}

	{
		QMutexLocker locker(ctx->mutex());

		ret = isds_send_message(ctx->ctx(), msg);
		if (Q_UNLIKELY(ret != IE_SUCCESS)) {
			err.setCode(libisds2Error(ret));
			err.setLongDescr(IsdsInternal::isdsLongMessage(ctx->ctx()));
			goto fail;
		}
	}

	if (Q_UNLIKELY(msg->envelope->dmID == NULL)) {
		Q_ASSERT(0);
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Missing identifier of sent message."));
		goto fail;
	}

	ok = false;
	dmId = QString(msg->envelope->dmID).toLongLong(&ok);
	if (Q_UNLIKELY((!ok) || (dmId < 0))) {
		Q_ASSERT(0);
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Cannot convert sent message identifier."));
		goto fail;
	}

	err.setCode(Type::ERR_SUCCESS);

fail:
	if (msg != NULL) {
		isds_message_free(&msg);
	}

	return err;
}

Isds::Error Isds::Service::eraseMessage(Session *ctx, qint64 dmId,
    bool dmIncoming)
{
	Error err;

	if (Q_UNLIKELY((ctx == Q_NULLPTR) || (dmId < 0))) {
		Q_ASSERT(0);
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Insufficient input."));
		return err;
	}

	{
		QMutexLocker locker(ctx->mutex());

		isds_error ret = isds_delete_message_from_storage(ctx->ctx(),
		    QString::number(dmId).toUtf8().constData(), dmIncoming);
		if (Q_UNLIKELY(ret != IE_SUCCESS)) {
			err.setCode(libisds2Error(ret));
			err.setLongDescr(IsdsInternal::isdsLongMessage(ctx->ctx()));
			return err;
		}
	}

	err.setCode(Type::ERR_SUCCESS);
	return err;
}

Isds::Error Isds::Service::getListOfReceivedMessages(Session *ctx,
    Type::DmFiltStates dmStatusFilter, unsigned long int dmOffset,
    unsigned long int *dmLimit, QList<Message> &messages)
{
	return ServicePrivate::messageListGetterService(
	    ServicePrivate::MLG_RECEIVED, ctx, dmStatusFilter, dmOffset,
	    dmLimit, messages);
}

Isds::Error Isds::Service::getListOfSentMessages(Session *ctx,
    Type::DmFiltStates dmStatusFilter, unsigned long int dmOffset,
    unsigned long int *dmLimit, QList<Message> &messages)
{
	return ServicePrivate::messageListGetterService(
	    ServicePrivate::MLG_SENT, ctx, dmStatusFilter, dmOffset,
	    dmLimit, messages);
}

/*!
 * @brief Converts sender type.
 */
static
enum Isds::Type::SenderType libisdsSenderType2SenderType(isds_sender_type st,
    bool *ok = Q_NULLPTR)
{
	bool iOk = true;
	enum Isds::Type::SenderType type = Isds::Type::ST_NULL;

	switch (st) {
	case SENDERTYPE_PRIMARY: type = Isds::Type::ST_PRIMARY; break;
	case SENDERTYPE_ENTRUSTED: type = Isds::Type::ST_ENTRUSTED; break;
	case SENDERTYPE_ADMINISTRATOR: type = Isds::Type::ST_ADMINISTRATOR; break;
	case SENDERTYPE_OFFICIAL: type = Isds::Type::ST_OFFICIAL; break;
	case SENDERTYPE_VIRTUAL: type = Isds::Type::ST_VIRTUAL; break;
	case SENDERTYPE_OFFICIAL_CERT: type = Isds::Type::ST_OFFICIAL_CERT; break;
	case SENDERTYPE_LIQUIDATOR: type = Isds::Type::ST_LIQUIDATOR; break;
	case SENDERTYPE_RECEIVER: type = Isds::Type::ST_RECEIVER; break;
	case SENDERTYPE_GUARDIAN: type = Isds::Type::ST_GUARDIAN; break;
	default:
		Q_ASSERT(0);
		iOk = false;
		break;
	}

	if (ok != Q_NULLPTR) {
		*ok = iOk;
	}
	return type;
}

Isds::Error Isds::Service::getMessageAuthor(Session *ctx, qint64 dmId,
    enum Type::SenderType &userType, QString &authorName)
{
	Error err;

	if (Q_UNLIKELY((ctx == Q_NULLPTR) || (dmId < 0))) {
		Q_ASSERT(0);
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Insufficient input."));
		return err;
	}

	isds_sender_type *s_type = NULL;
	char *s_name = NULL;
	bool ok = true;

	{
		QMutexLocker locker(ctx->mutex());

		isds_error ret = isds_get_message_sender(ctx->ctx(),
		    QString::number(dmId).toUtf8().constData(), &s_type, NULL,
		    &s_name);
		if (Q_UNLIKELY(ret != IE_SUCCESS)) {
			err.setCode(libisds2Error(ret));
			err.setLongDescr(IsdsInternal::isdsLongMessage(ctx->ctx()));
			goto fail;
		}
	}

	userType = (s_type != NULL) ?
	    libisdsSenderType2SenderType(*s_type, &ok) : Type::ST_NULL;
	authorName = (s_name != NULL) ? QString(s_name) : QString();

	if (ok) {
		err.setCode(Type::ERR_SUCCESS);
	} else {
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Error converting types."));
	}

fail:
	if (s_type != NULL) {
		::std::free(s_type); s_type = NULL;
	}
	if (s_name != NULL) {
		::std::free(s_name); s_name = NULL;
	}

	return err;
}

Isds::Error Isds::Service::getSignedDeliveryInfo(Session *ctx, qint64 dmId,
    Message &message)
{
	return ServicePrivate::messageGetterService(
	    ServicePrivate::MG_SIGNED_DELIVERY_INFO, ctx, dmId, message);
}

Isds::Error Isds::Service::markMessageAsDownloaded(Session *ctx, qint64 dmId)
{
	Error err;

	if (Q_UNLIKELY((ctx == Q_NULLPTR) || (dmId < 0))) {
		Q_ASSERT(0);
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Insufficient input."));
		return err;
	}

	{
		QMutexLocker locker(ctx->mutex());

		isds_error ret = isds_mark_message_read(ctx->ctx(),
		    QString::number(dmId).toUtf8().constData());
		if (Q_UNLIKELY(ret != IE_SUCCESS)) {
			err.setCode(libisds2Error(ret));
			err.setLongDescr(IsdsInternal::isdsLongMessage(ctx->ctx()));
			return err;
		}
	}

	err.setCode(Type::ERR_SUCCESS);
	return err;
}

Isds::Error Isds::Service::signedReceivedMessageDownload(Session *ctx,
    qint64 dmId, Message &message)
{
	return ServicePrivate::messageGetterService(
	    ServicePrivate::MG_SIGNED_RECEIVED_MESSAGE, ctx, dmId, message);
}

Isds::Error Isds::Service::signedSentMessageDownload(Session *ctx, qint64 dmId,
    Message &message)
{
	return ServicePrivate::messageGetterService(
	    ServicePrivate::MG_SIGNED_SENT_MESSAGE, ctx, dmId, message);
}

Isds::Error Isds::Service::verifyMessage(Session *ctx, qint64 dmId, Hash &hash)
{
	Error err;

	if (Q_UNLIKELY((ctx == Q_NULLPTR) || (dmId < 0))) {
		Q_ASSERT(0);
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Insufficient input."));
		return err;
	}

	struct isds_hash *iHash = NULL;
	bool ok = true;

	{
		QMutexLocker locker(ctx->mutex());

		isds_error ret = isds_download_message_hash(ctx->ctx(),
		    QString::number(dmId).toUtf8().constData(), &iHash);
		if (Q_UNLIKELY(ret != IE_SUCCESS)) {
			err.setCode(libisds2Error(ret));
			err.setLongDescr(IsdsInternal::isdsLongMessage(ctx->ctx()));
			goto fail;
		}
	}

	hash = (iHash != NULL) ? libisds2hash(iHash, &ok) : Hash();

	if (ok) {
		err.setCode(Type::ERR_SUCCESS);
	} else {
		err.setCode(Type::ERR_ERROR);
		err.setLongDescr(tr("Error converting types."));
	}

fail:
	if (iHash != NULL) {
		isds_hash_free(&iHash);
	}

	return err;
}
