/*
    mephi-tasks — a client to NRNU MEPhI Redmine server

    Copyright (C) 2015  Dmitry Yu Okunev <dyokunev@ut.mephi.ru> 0x8E30679C

    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/>.
 */

#include "redmine.h"
#include "common.h"

#include <QDir>
#include <QFile>
#include <QStandardPaths>
#include <QMessageBox>

Redmine::Redmine()
{
	if ( ! QSslSocket::supportsSsl() ) {
		qDebug ( "! QSslSocket::supportsSsl()" );
		QMessageBox messageBox;
		messageBox.critical(0, "Error", "Отсутствует поддержка SSL. Проверьте наличие библиотек libeay32.dll и ssleay32.dll, либо установите пакет OpenSSL.");
	}
	this->setBaseUrl ( SERVER_URL );

#ifdef __MOBILE__
	this->cacheBasePath = QStandardPaths::writableLocation(QStandardPaths::CacheLocation);
#else
	this->cacheBasePath = "cache/";
#endif
}

Redmine::~Redmine()
{
	this->cacheSave();
}

QString Redmine::apiKey ( QString apiKey )
{
	return this->_apiKey = apiKey;
}

QString Redmine::apiKey()
{
	return this->_apiKey;
}

/*
void Redmine::init_quitStatuses(QNetworkReply *reply, QJsonDocument *statuses, void *_null) {
    (void)_null; (void)reply; (void)statuses;

    this->initBarrier_jobsDone++;

    if (this->initBarrier_jobsDone >= 3)
        this->initBarrier.exit();
}
void Redmine::init_quitMe(QNetworkReply *reply, QJsonDocument *me, void *_null) {
    (void)_null; (void)reply; (void)statuses;

    this->initBarrier_jobsDone++;

    if (this->initBarrier_jobsDone >= 3)
        this->initBarrier.exit();
}
void Redmine::init_quitMyProject(QNetworkReply *reply, QJsonDocument *myProject, void *_null) {
    (void)_null; (void)reply; (void)statuses;

    this->initBarrier_jobsDone++;

    if (this->initBarrier_jobsDone >= 3)
        this->initBarrier.exit();
}
*/

int Redmine::init()
{
	if ( this->apiKey().length() > 0 ) {
		this->setAuth ( this->_apiKey );
	}

	connect ( this, SIGNAL ( requestFinished     ( void*, callback_t, QNetworkReply*, QJsonDocument*, void* ) ),
		  this, SLOT   ( callback_dispatcher ( void*, callback_t, QNetworkReply*, QJsonDocument*, void* ) ) );
	this->initBarrier_jobsDone = 0;
	QNetworkReply *updateIssueStatusesReply = this->updateIssueStatuses();
	// Wait until issue statuses will be received:
	connect ( updateIssueStatusesReply, SIGNAL ( finished() ), &this->initBarrier, SLOT ( quit() ) );
	this->initBarrier.exec();
	QNetworkReply *updateMeReply            = this->updateMe();
	// Wait until infomation about current user will be received:
	connect ( updateMeReply, SIGNAL ( finished() ), &this->initBarrier, SLOT ( quit() ) );
	this->initBarrier.exec();
	QNetworkReply *updateMyProjectReply     = this->updateMyProject();
	// Wait until infomation about current user will be received:
	connect ( updateMyProjectReply, SIGNAL ( finished() ), &this->initBarrier, SLOT ( quit() ) );
	this->initBarrier.exec();
	this->cacheLoad();
	return 0;
}

/********* cache{Load,Save} *********/

void Redmine::cacheLoad()
{
	QDir dir = QDir ( this->cacheBasePath + this->apiKey() );
	QFileInfoList fileInfoList = dir.entryInfoList ( QDir::Files );

	for ( int i = 0; i < fileInfoList.size(); ++i ) {
		QFileInfo fileInfo = fileInfoList.at ( i );
		QString filePath = fileInfo.absoluteFilePath();
		QString fileName = fileInfo.fileName();
		QFile *file = new QFile ( filePath );

		if ( !file->open ( QIODevice::ReadOnly ) ) {
			qDebug ( "cannot open file \"%s\" for reading", filePath.toUtf8().data() );
			continue;
		}

		QByteArray jsonText = qUncompress ( file->readAll() );
		QString    uri      = fileName.replace ( "!", "/" );
		this->cache[uri]    = QJsonDocument::fromJson ( jsonText );
		delete file;
	}

	return;
}

void Redmine::cacheSave()
{
	QHash<QString, QJsonDocument>::iterator i;
	QDir dir = QDir();

	if ( !dir.mkpath ( "cache/" + this->apiKey() ) ) {
		qDebug ( "cannot create cache directory" );
		return;
	}

	for ( i = this->cache.begin(); i != this->cache.end(); ++i ) {
		QByteArray jsonText = qCompress ( i.value().toJson() );
		QString fileName = i.key();
		fileName = fileName.replace ( "/", "!" );
		QString filePath = "cache/" + this->apiKey() + "/" + fileName;
		QFile *file = new QFile ( dir.filePath ( filePath ) );

		if ( !file->open ( QIODevice::WriteOnly ) ) {
			qDebug ( "cannot open file \"%s\" for writting", fileName.toUtf8().data() );
			continue;
		}

		file->write ( jsonText );
		file->close();
		delete file;
	}

	return;
}

/********* /cache{Load,Save} *********/

/********* request *********/

struct redmine_request_callback_arg {
	void                *obj_ptr;
	Redmine::callback_t  callback;
	void                *arg;
	bool                 free_arg;
	QString              signature;
};


void Redmine::callback_cache ( QNetworkReply *reply, QJsonDocument *obj, void *_real_callback_info )
{
	struct redmine_request_callback_arg *real_callback_info =
	    ( struct redmine_request_callback_arg * ) _real_callback_info;
	qDebug ( "Got a reply for \"%s\"", real_callback_info->signature.toStdString().c_str() );

	if ( real_callback_info->callback != NULL )
		this->callback_call ( real_callback_info->obj_ptr, real_callback_info->callback, reply, obj, real_callback_info->arg );

	//real_callback_info->callback(reply, obj, real_callback_info->arg);

	if ( real_callback_info->free_arg )
		free ( real_callback_info->arg );

	this->cache.insert ( real_callback_info->signature, *obj );
	delete real_callback_info;
	return;
}

QNetworkReply *Redmine::request ( RedmineClient::EMode    mode,
                                  QString                 uri,
                                  void                   *obj_ptr,
                                  callback_t              callback,
                                  void                   *callback_arg,
                                  bool                    free_arg,
                                  const QString          &getParams,
                                  const QByteArray       &requestData,
                                  bool                    useCache
                                )
{
	if ( mode != RedmineClient::EMode::GET || useCache == false ) {
		return this->sendRequest ( uri, RedmineClient::JSON, mode, obj_ptr,
		                           ( RedmineClient::callback_t ) callback, callback_arg, free_arg, getParams, requestData );
	}

	qDebug ( "obj_ptr == %p", obj_ptr );
	QString signature = uri + "?" + getParams;

	if ( !this->cache[signature].isEmpty() ) {
		qDebug ( "Found cache for \"%s\"", signature.toStdString().c_str() );
		if (obj_ptr != NULL && callback != NULL)
			this->callback_call ( obj_ptr, callback, NULL, &this->cache[signature], callback_arg );
	}

	/*
	QPair <QByteArray, QByteArray> hashes;
	hashes.first  = QCryptographicHash::hash(signature, QCryptographicHash::Md5);
	hashes.second = QCryptographicHash::hash(signature, QCryptographicHash::Sha1);
	*/
	{
		struct redmine_request_callback_arg *real_callback_info = new struct redmine_request_callback_arg;
		//(struct redmine_request_callback_arg *)calloc(1, sizeof(*real_callback_info));
		real_callback_info->obj_ptr   = obj_ptr;
		real_callback_info->callback  = callback;
		real_callback_info->arg       = callback_arg;
		real_callback_info->free_arg  = free_arg;
		real_callback_info->signature = signature;
		qDebug ( "Makeing a request for \"%s\"", signature.toStdString().c_str() );
		return this->sendRequest ( uri, RedmineClient::JSON, mode, this,
		                           ( RedmineClient::callback_t ) &Redmine::callback_cache, real_callback_info, false, getParams, requestData );
	}
}

QNetworkReply *Redmine::request ( RedmineClient::EMode    mode,
                                  QString                 uri,
                                  void                   *obj_ptr,
                                  callback_t              callback,
                                  void                   *callback_arg,
                                  bool                    free_arg,
                                  const QString          &getParams,
                                  const QJsonObject      &requestJSON
                                )
{
	return this->request ( mode, uri, obj_ptr, callback, callback_arg, free_arg, getParams, QJsonDocument ( requestJSON ).toJson() );
}

QNetworkReply *Redmine::request ( RedmineClient::EMode    mode,
                                  QString                 uri,
                                  void                   *obj_ptr,
                                  callback_t              callback,
                                  void                   *callback_arg,
                                  bool                    free_arg,
                                  const QString          &getParams,
                                  const QVariantMap      &requestVMap
                                )
{
	return this->request ( mode, uri, obj_ptr, callback, callback_arg, free_arg, getParams, QJsonObject::fromVariantMap ( requestVMap ) );
}

/********* /request *********/

/********* updateMe *********/

struct redmine_updateMe_callback_arg {
	Redmine::callback_t  real_callback;
	void                *arg;
};

void Redmine::updateMe_callback ( QNetworkReply *reply, QJsonDocument *me_doc, void *_arg )
{
	( void ) reply;
	struct redmine_updateMe_callback_arg *arg =
	    ( struct redmine_updateMe_callback_arg * ) _arg;
	callback_t  callback;
	void       *callback_arg;
	this->_me = me_doc->object() ["user"].toObject();

	if ( _arg != NULL ) {
		callback     = arg->real_callback;
		callback_arg = arg->arg;
		this->callback_call ( NULL, callback, reply, me_doc, callback_arg );
	}

	return;
}

QNetworkReply *Redmine::updateMe ( callback_t callback, void *arg )
{
	struct redmine_updateMe_callback_arg *wrapper_arg = NULL;

	if ( callback != NULL ) {
		wrapper_arg =
		    ( struct redmine_updateMe_callback_arg * )
		    calloc ( 1, sizeof ( struct redmine_updateMe_callback_arg ) );
		wrapper_arg->real_callback = callback;
		wrapper_arg->arg           = arg;
	}

	return this->request (
	           GET,
	           "users/current",
	           this,
	           &Redmine::updateMe_callback,
	           wrapper_arg,
	           true,
	           NULL,
	           NULL,
	           false );
}

/********* /updateMe *********/


/********* updateMyProject *********/

struct redmine_updateMyProject_callback_arg {
	Redmine::callback_t  real_callback;
	void                *arg;
};

void Redmine::updateMyProject_callback ( QNetworkReply *reply, QJsonDocument *myProject_doc, void *_arg )
{
	( void ) reply;
	struct redmine_updateMyProject_callback_arg *arg =
	    ( struct redmine_updateMyProject_callback_arg * ) _arg;
	callback_t  callback;
	void       *callback_arg;
	this->_myProject = myProject_doc->object() ["project"].toObject();

	if ( _arg != NULL ) {
		callback     = arg->real_callback;
		callback_arg = arg->arg;
		this->callback_call ( NULL, callback, reply, myProject_doc, callback_arg );
	}

	return;
}

QNetworkReply *Redmine::updateMyProject ( callback_t callback, void *arg )
{
	struct redmine_updateMyProject_callback_arg *wrapper_arg = NULL;

	if ( callback != NULL ) {
		wrapper_arg =
		    ( struct redmine_updateMyProject_callback_arg * )
		    calloc ( 1, sizeof ( struct redmine_updateMyProject_callback_arg ) );
		wrapper_arg->real_callback = callback;
		wrapper_arg->arg           = arg;
	}

	return this->request (
	           GET,
	           "projects/" + this->me() ["login"].toString(),
	           this,
	           &Redmine::updateMyProject_callback,
	           wrapper_arg,
	           true,
	           NULL,
	           NULL,
	           false );
}

/********* /updateMyProject *********/

/********* updateIssueStatuses *********/

struct redmine_updateIssueStatuses_callback_arg {
	Redmine::callback_t  real_callback;
	void                *arg;
};

void Redmine::set_issue_status ( int status_id, QJsonObject status )
{
	this->issue_statuses.insert ( status_id, status );
	return;
}

void Redmine::clear_issue_status()
{
	this->issue_statuses.clear();
}

QJsonObject Redmine::get_issue_status ( int issue_status_id )
{
	return this->issue_statuses[issue_status_id];
}

QJsonObject Redmine::get_issue_status ( QJsonValueRef issues_status_json )
{
	return this->get_issue_status ( issues_status_json.toObject() ["id"].toInt() );
}

QHash<int, QJsonObject> Redmine::get_available_statuses_for ( int issue_id )
{
	( void ) issue_id;
	return this->issue_statuses;
}

void Redmine::updateIssueStatuses_callback ( QNetworkReply *reply, QJsonDocument *statuses_doc, void *_arg )
{
	( void ) reply;
	struct redmine_updateIssueStatuses_callback_arg *arg =
	    ( struct redmine_updateIssueStatuses_callback_arg * ) _arg;
	callback_t  callback;
	void       *callback_arg;
	int statuses_count = 0;
	QJsonArray statuses = statuses_doc->object() ["issue_statuses"].toArray();
	this->clear_issue_status();
	foreach ( const QJsonValue & status_val, statuses ) {
		QJsonObject status = status_val.toObject();
		status["position"] = statuses_count++;
		this->set_issue_status ( status["id"].toInt(), status );
	}

	if ( arg != NULL ) {
		callback     = arg->real_callback;
		callback_arg = arg->arg;
		this->callback_call ( NULL, callback, reply, statuses_doc, callback_arg );
	}

	return;
}

QNetworkReply *Redmine::updateIssueStatuses ( callback_t callback, void *arg )
{
	struct redmine_updateIssueStatuses_callback_arg *wrapper_arg = NULL;

	if ( callback != NULL ) {
		wrapper_arg =
		    ( struct redmine_updateIssueStatuses_callback_arg * )
		    calloc ( 1, sizeof ( struct redmine_updateIssueStatuses_callback_arg ) );
		wrapper_arg->real_callback = callback;
		wrapper_arg->arg           = arg;
	}

	return this->request ( GET,
	                       "issue_statuses",
	                       this,
	                       &Redmine::updateIssueStatuses_callback,
	                       wrapper_arg,
	                       true,
	                       NULL,
	                       NULL,
	                       false );
}

/********* /updateIssueStatuses *********/

/********* get_memberships *********/

QNetworkReply *Redmine::get_memberships ( callback_t callback,
        void *arg, bool free_arg )
{
	return this->request ( GET, "memberships", NULL, callback, arg, free_arg, "limit=5000" );
}

/********* /get_memberships *********/

/********* get_enumerations *********/

QNetworkReply *Redmine::get_enumerations ( callback_t callback,
        void *arg, bool free_arg )
{
	return this->request ( GET, "enumerations", NULL, callback, arg, free_arg, "limit=5000" );
}

/********* /get_enumerations *********/

/********* get_roles *********/

QNetworkReply *Redmine::get_roles ( callback_t callback,
                                    void *arg, bool free_arg )
{
	return this->request ( GET, "roles", NULL, callback, arg, free_arg, "limit=5000" );
}

/********* /get_roles *********/

/********* get_issues *********/

QNetworkReply *Redmine::get_issues ( void *obj_ptr, callback_t callback,
                                     void *arg, bool free_arg, QString customFilters )
{
	return this->request ( GET, "issues", obj_ptr, callback, arg, free_arg, customFilters + "&" + settings.issuesFilter );
}

QNetworkReply *Redmine::get_issues ( callback_t callback,
                                     void *arg, bool free_arg, QString customFilters )
{
	return this->get_issues ( NULL, callback, arg, free_arg, customFilters );
}

/********* /get_issues *********/

/********* get_time_entries *********/

QNetworkReply *Redmine::get_time_entries ( void *obj_ptr, callback_t callback,
        void *arg, bool free_arg, QString filterOptions )
{
	return this->request ( GET, "time_entries", obj_ptr, callback, arg, free_arg, filterOptions );
}

QNetworkReply *Redmine::get_time_entries ( callback_t callback,
        void *arg, bool free_arg, QString filterOptions )
{
	qDebug("deprecated variant of Redmine::get_time_entries had been called");

	return this->get_time_entries ( NULL, callback, arg, free_arg, filterOptions );
}

QNetworkReply *Redmine::get_time_entries ( int userId, void *obj_ptr, callback_t callback,
	void *arg, bool free_arg, QString filterOptions )
{
	QString userId_str = ( userId == 0 ? "" : QString ( "user_id=" + QString::number(userId) ) );

	return this->get_time_entries ( obj_ptr, callback, arg, free_arg, userId_str+"&"+filterOptions );
}

/********* /get_time_entries *********/

/********* get_projects *********/

QNetworkReply *Redmine::get_projects ( void *obj_ptr, callback_t callback,
                                       void *arg, bool free_arg, QString filterOptions )
{
	return this->request ( GET, "projects", obj_ptr, callback, arg, free_arg, "limit=500&" + filterOptions );
}

QNetworkReply *Redmine::get_projects ( callback_t callback,
                                       void *arg, bool free_arg, QString filterOptions )
{
	return this->get_projects ( NULL, callback, arg, free_arg, filterOptions );
}

/********* /get_projects *********/

/********* get_user *********/

struct get_user_callback_arg {
	int                   user_id;
	Redmine::callback_t   real_callback;
	void                 *arg;
};

// Caching function

void Redmine::get_user_callback (
    QNetworkReply *reply,
    QJsonDocument *user_doc,
    void *_arg )
{
	struct get_user_callback_arg *arg = ( struct get_user_callback_arg * ) _arg;
	int        user_id  = arg->user_id;
	callback_t callback = arg->real_callback;

	if ( user_doc != NULL )
		this->users[user_id] = *user_doc;

	this->callback_call ( NULL, callback, reply, &this->users[user_id], arg->arg );
	return;
}

QNetworkReply *Redmine::get_user ( int user_id,
                                   callback_t callback,
                                   void *arg )
{
	struct get_user_callback_arg *get_user_callback_arg_p = NULL;

	if ( this->users.contains ( user_id ) ) {
		this->callback_call ( NULL, callback, NULL, &this->users[user_id], arg );
		return 0;
	}

	get_user_callback_arg_p =
	    ( struct get_user_callback_arg * ) calloc ( 1, sizeof ( struct get_user_callback_arg ) );
	get_user_callback_arg_p->user_id       = user_id;
	get_user_callback_arg_p->real_callback = callback;
	get_user_callback_arg_p->arg           = arg;
	return this->request (
	           GET,
	           "users/" + QString::number ( user_id ),
	           this,
	           &Redmine::get_user_callback,
	           get_user_callback_arg_p,
	           true,
	           NULL,
	           NULL,
	           false );
}

/********* /get_user *********/

/********* parseDateTime *********/

QDateTime Redmine::parseDateTime ( QString date_str )
{
	qDebug ( "Used deprecated function Redmine::parseDateTime(). Use \"QDateTime::fromString (arg, Qt::ISODate)\" instead." );

	// TODO: FIXME: make this function working on any timezone.
	QDateTime date;
	date = QDateTime::fromString ( date_str, "yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'zzz'+03:00'" );

	if ( !date.isValid() )
		date = QDateTime::fromString ( date_str, "yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'zzz'+0300'" );

	if ( !date.isValid() )
		// TODO: FIXME: add a hour
		date = QDateTime::fromString ( date_str, "yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'zzz'+04:00'" );

	if ( !date.isValid() )
		// TODO: FIXME: add a hour
		date = QDateTime::fromString ( date_str, "yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'zzz'+0400'" );

	return date;
}

QDateTime Redmine::parseDateTime ( QJsonValueRef dataTime_json )
{
	return this->parseDateTime ( dataTime_json.toString() );
}

/********* /parseDateTime *********/

/********* getUrl *********/

QUrl Redmine::getUrl ( QString objectType, int objectId )
{
	return QUrl ( this->getBaseUrl() + "/" + objectType + "s/" + QString::number ( objectId ) );
}

/********* /getUrl *********/

/********* get_stuff_to_do *********/

QNetworkReply *Redmine::get_stuff_to_do ( void *obj_ptr, callback_t callback,
				 int user_id,
				 void *arg, bool free_arg,
				 QString filterOptions )
{
	QString user_id_str = ( user_id == 0 ? "" : "user_id=" + QString::number ( user_id ) );

	return this->request(
				GET,
				"stuff_to_do",
				obj_ptr,
				callback,
				arg,
				free_arg,
				user_id_str+"&"+filterOptions );
}

/********* /get_stuff_to_do *********/