#include "subsurfacewebservices.h"
#include "../webservice.h"
#include "mainwindow.h"

#include <libxml/parser.h>
#include <zip.h>

#include <QDir>
#include <QHttpMultiPart>
#include <QMessageBox>
#include <QNetworkAccessManager>
#include <QNetworkReply>
#include <QDebug>
#include <QSettings>
#include <QXmlStreamReader>
#include <qdesktopservices.h>

#include "../dive.h"
#include "../divelist.h"

#ifdef Q_OS_UNIX
#  include <unistd.h> // for dup(2)
#endif

struct dive_table gps_location_table;
static bool merge_locations_into_dives(void);

static bool is_automatic_fix(struct dive *gpsfix)
{
	if (gpsfix && gpsfix->location &&
			(!strcmp(gpsfix->location, "automatic fix") ||
			 !strcmp(gpsfix->location, "Auto-created dive")))
		return TRUE;
	return FALSE;
}

#define SAME_GROUP 6 * 3600   // six hours

static bool merge_locations_into_dives(void)
{
	int i, nr = 0, changed = 0;
	struct dive *gpsfix, *last_named_fix = NULL, *dive;

	sort_table(&gps_location_table);

	for_each_gps_location(i, gpsfix) {
		if (is_automatic_fix(gpsfix)) {
			dive = find_dive_including(gpsfix->when);
			if (dive && !dive_has_gps_location(dive)) {
#if DEBUG_WEBSERVICE
				struct tm tm;
				utc_mkdate(gpsfix->when, &tm);
				printf("found dive named %s @ %04d-%02d-%02d %02d:%02d:%02d\n",
				       gpsfix->location,
				       tm.tm_year+1900, tm.tm_mon+1, tm.tm_mday,
				       tm.tm_hour, tm.tm_min, tm.tm_sec);
#endif
				changed++;
				copy_gps_location(gpsfix, dive);
			}
		} else {
			if (last_named_fix && dive_within_time_range(last_named_fix, gpsfix->when, SAME_GROUP)) {
				nr++;
			} else {
				nr = 1;
				last_named_fix = gpsfix;
			}
			dive = find_dive_n_near(gpsfix->when, nr, SAME_GROUP);
			if (dive) {
				if (!dive_has_gps_location(dive)) {
					copy_gps_location(gpsfix, dive);
					changed++;
				}
				if (!dive->location) {
					dive->location = strdup(gpsfix->location);
					changed++;
				}
			} else {
				struct tm tm;
				utc_mkdate(gpsfix->when, &tm);
#if DEBUG_WEBSERVICE
				printf("didn't find dive matching gps fix named %s @ %04d-%02d-%02d %02d:%02d:%02d\n",
				       gpsfix->location,
				       tm.tm_year+1900, tm.tm_mon+1, tm.tm_mday,
				       tm.tm_hour, tm.tm_min, tm.tm_sec);
#endif
			}
		}
	}
	return changed > 0;
}

static void clear_table(struct dive_table *table)
{
	int i;
	for (i = 0; i < table->nr; i++)
		free(table->dives[i]);
	table->nr = 0;
}

WebServices::WebServices(QWidget* parent, Qt::WindowFlags f): QDialog(parent, f)
, reply(0)
{
	ui.setupUi(this);
	connect(ui.buttonBox, SIGNAL(clicked(QAbstractButton*)), this, SLOT(buttonClicked(QAbstractButton*)));
	connect(ui.download, SIGNAL(clicked(bool)), this, SLOT(startDownload()));
	connect(ui.upload, SIGNAL(clicked(bool)), this, SLOT(startUpload()));
	connect(&timeout, SIGNAL(timeout()), this, SLOT(downloadTimedOut()));
	ui.buttonBox->button(QDialogButtonBox::Apply)->setEnabled(false);
	timeout.setSingleShot(true);
}

void WebServices::hidePassword()
{
	ui.password->hide();
	ui.passLabel->hide();
}

void WebServices::hideUpload()
{
	ui.upload->hide();
	ui.download->show();
}

void WebServices::hideDownload()
{
	ui.download->hide();
	ui.upload->show();
}

QNetworkAccessManager *WebServices::manager()
{
	static QNetworkAccessManager *manager = new QNetworkAccessManager(qApp);
	return manager;
}

void WebServices::downloadTimedOut()
{
	if (!reply)
		return;

	reply->deleteLater();
	reply = NULL;
	resetState();
	ui.status->setText(tr("Operation timed out"));
}

void WebServices::updateProgress(qint64 current, qint64 total)
{
	if (!reply)
		return;

	if (total >= INT_MAX / 2) {
		// over a gigabyte!
		if (total >= Q_INT64_C(1) << 47) {
			total >>= 16;
			current >>= 16;
		}
		total >>= 16;
		current >>= 16;
	}
	ui.progressBar->setRange(0, total);
	ui.progressBar->setValue(current);
	ui.status->setText(tr("Transfering data..."));

	// reset the timer: 30 seconds after we last got any data
	timeout.start();
}

void WebServices::connectSignalsForDownload(QNetworkReply *reply)
{
	connect(reply, SIGNAL(finished()), this, SLOT(downloadFinished()));
	connect(reply, SIGNAL(error(QNetworkReply::NetworkError)),
		this, SLOT(downloadError(QNetworkReply::NetworkError)));
	connect(reply, SIGNAL(downloadProgress(qint64,qint64)), this,
		SLOT(updateProgress(qint64,qint64)));

	timeout.start(30000); // 30s
}

void WebServices::resetState()
{
	ui.download->setEnabled(true);
	ui.upload->setEnabled(true);
	ui.userID->setEnabled(true);
	ui.password->setEnabled(true);
	ui.progressBar->reset();
	ui.progressBar->setRange(0,1);
	ui.status->setText(QString());
}

// #
// #
// #		Subsurface Web Service Implementation.
// #
// #

SubsurfaceWebServices* SubsurfaceWebServices::instance()
{
	static SubsurfaceWebServices *self = new SubsurfaceWebServices(mainWindow());
	self->setAttribute(Qt::WA_QuitOnClose, false);
	return self;
}

SubsurfaceWebServices::SubsurfaceWebServices(QWidget* parent, Qt::WindowFlags f)
{
	QSettings s;
	ui.userID->setText(s.value("subsurface_webservice_uid").toString().toUpper());
	hidePassword();
	hideUpload();
}

void SubsurfaceWebServices::buttonClicked(QAbstractButton* button)
{
	ui.buttonBox->button(QDialogButtonBox::Apply)->setEnabled(false);
	switch(ui.buttonBox->buttonRole(button)){
	case QDialogButtonBox::ApplyRole:{
		clear_table(&gps_location_table);
		QByteArray url = tr("Webservice").toLocal8Bit();
		parse_xml_buffer(url.data(), downloadedData.data(), downloadedData.length(), &gps_location_table, NULL, NULL);

		/* now merge the data in the gps_location table into the dive_table */
		if (merge_locations_into_dives()) {
			mark_divelist_changed(TRUE);
		}

		/* store last entered uid in config */
		QSettings s;
		s.setValue("subsurface_webservice_uid", ui.userID->text().toUpper());
		s.sync();
		hide();
		close();
		resetState();
	}
		break;
	case QDialogButtonBox::RejectRole:
		// we may want to clean up after ourselves
		// reply->deleteLater();
		reply = NULL;
		resetState();
		break;
	case QDialogButtonBox::HelpRole:
		QDesktopServices::openUrl(QUrl("http://api.hohndel.org"));
		break;
	default:
		break;
	}
}

void SubsurfaceWebServices::startDownload()
{
	QUrl url("http://api.hohndel.org/api/dive/get/");
	url.addQueryItem("login", ui.userID->text().toUpper());

	QNetworkRequest request;
	request.setUrl(url);
	request.setRawHeader("Accept", "text/xml");
	reply = manager()->get(request);
	ui.status->setText(tr("Connecting..."));
	ui.progressBar->setRange(0,0); // this makes the progressbar do an 'infinite spin'
	ui.download->setEnabled(false);
	ui.buttonBox->button(QDialogButtonBox::Apply)->setEnabled(false);
	connectSignalsForDownload(reply);
}

void SubsurfaceWebServices::downloadFinished()
{
	if (!reply)
		return;

	ui.progressBar->setRange(0,1);
	downloadedData = reply->readAll();

	ui.download->setEnabled(true);
	ui.status->setText(tr("Download finished"));

	uint resultCode = download_dialog_parse_response(downloadedData);
	setStatusText(resultCode);
	if (resultCode == DD_STATUS_OK){
		ui.buttonBox->button(QDialogButtonBox::Apply)->setEnabled(true);
	}
	reply->deleteLater();
	reply = NULL;
}

void SubsurfaceWebServices::downloadError(QNetworkReply::NetworkError)
{
	resetState();
	ui.status->setText(tr("Download error: %1").arg(reply->errorString()));
	reply->deleteLater();
	reply = NULL;
}

void SubsurfaceWebServices::setStatusText(int status)
{
	QString text;
	switch (status)	{
	case DD_STATUS_ERROR_CONNECT: text = tr("Connection Error: ");		break;
	case DD_STATUS_ERROR_ID:	  text = tr("Invalid user identifier!"); break;
	case DD_STATUS_ERROR_PARSE:	  text = tr("Cannot parse response!");	break;
	case DD_STATUS_OK:			  text = tr("Download Success!"); break;
	}
	ui.status->setText(text);
}

/* requires that there is a <download> or <error> tag under the <root> tag */
void SubsurfaceWebServices::download_dialog_traverse_xml(xmlNodePtr node, unsigned int *download_status)
{
	xmlNodePtr cur_node;
	for (cur_node = node; cur_node; cur_node = cur_node->next) {
		if ((!strcmp((const char *)cur_node->name, (const char *)"download")) &&
				(!strcmp((const char *)xmlNodeGetContent(cur_node), (const char *)"ok"))) {
			*download_status = DD_STATUS_OK;
			return;
		}	else if (!strcmp((const char *)cur_node->name, (const char *)"error")) {
			*download_status = DD_STATUS_ERROR_ID;
			return;
		}
	}
}

unsigned int SubsurfaceWebServices::download_dialog_parse_response(const QByteArray& xml)
{
	xmlNodePtr root;
	xmlDocPtr doc = xmlParseMemory(xml.data(), xml.length());
	unsigned int status = DD_STATUS_ERROR_PARSE;

	if (!doc)
		return DD_STATUS_ERROR_PARSE;
	root = xmlDocGetRootElement(doc);
	if (!root) {
		status = DD_STATUS_ERROR_PARSE;
		goto end;
	}
	if (root->children)
		download_dialog_traverse_xml(root->children, &status);
end:
	xmlFreeDoc(doc);
	return status;
}

// #
// #
// #		Divelogs DE  Web Service Implementation.
// #
// #

struct DiveListResult
{
	QString errorCondition;
	QString errorDetails;
	QByteArray idList; // comma-separated, suitable to be sent in the fetch request
	int idCount;
};

static DiveListResult parseDiveLogsDeDiveList(const QByteArray &xmlData)
{
    /* XML format seems to be:
     * <DiveDateReader version="1.0">
     *   <DiveDates>
     *     <date diveLogsId="nnn" lastModified="YYYY-MM-DD hh:mm:ss">DD.MM.YYYY hh:mm</date>
     *     [repeat <date></date>]
     *   </DiveDates>
     * </DiveDateReader>
     */
    QXmlStreamReader reader(xmlData);
    const QString invalidXmlError = DivelogsDeWebServices::tr("Invalid response from server");
    bool seenDiveDates = false;
    DiveListResult result;
    result.idCount = 0;

    if (reader.readNextStartElement() && reader.name() != "DiveDateReader") {
	    result.errorCondition = invalidXmlError;
	    result.errorDetails =
			    DivelogsDeWebServices::tr("Expected XML tag 'DiveDateReader', got instead '%1")
			    .arg(reader.name().toString());
	    goto out;
    }

    while (reader.readNextStartElement()) {
	    if (reader.name() != "DiveDates") {
		    if (reader.name() == "Login") {
			    QString status = reader.readElementText();
			    // qDebug() << "Login status:" << status;

			    // Note: there has to be a better way to determine a successful login...
			    if (status == "failed") {
				    result.errorCondition = "Login failed";
				    goto out;
			    }
		    } else {
			    // qDebug() << "Skipping" << reader.name();
		    }
		    continue;
	    }

	    // process <DiveDates>
	    seenDiveDates = true;
	    while (reader.readNextStartElement()) {
		    if (reader.name() != "date") {
			    // qDebug() << "Skipping" << reader.name();
			    continue;
		    }
		    QStringRef id = reader.attributes().value("divelogsId");
		    // qDebug() << "Found" << reader.name() << "with id =" << id;
		    if (!id.isEmpty()) {
			    result.idList += id.toLatin1();
			    result.idList += ',';
			    ++result.idCount;
		    }

		    reader.skipCurrentElement();
	    }
    }

    // chop the ending comma, if any
    result.idList.chop(1);

    if (!seenDiveDates) {
	    result.errorCondition = invalidXmlError;
	    result.errorDetails = DivelogsDeWebServices::tr("Expected XML tag 'DiveDates' not found");
    }

out:
    if (reader.hasError()) {
	    // if there was an XML error, overwrite the result or other error conditions
	    result.errorCondition = invalidXmlError;
	    result.errorDetails = DivelogsDeWebServices::tr("Malformed XML response. Line %1: %2")
				  .arg(reader.lineNumber()).arg(reader.errorString());
    }
    return result;
}

DivelogsDeWebServices* DivelogsDeWebServices::instance()
{
	static DivelogsDeWebServices *self = new DivelogsDeWebServices(mainWindow());
	self->setAttribute(Qt::WA_QuitOnClose, false);
	return self;
}

void DivelogsDeWebServices::downloadDives()
{
	hideUpload();
	exec();
}

void DivelogsDeWebServices::uploadDives(QIODevice *dldContent)
{
	QHttpMultiPart mp(QHttpMultiPart::FormDataType);
	QHttpPart part;
	part.setRawHeader("Content-Disposition", "form-data; name=\"userfile\"");
	part.setBodyDevice(dldContent);
	mp.append(part);

	multipart = &mp;
	hideDownload();
	exec();
	multipart = NULL;

	delete reply; // we need to ensure it has stopped using our QHttpMultiPart
}

DivelogsDeWebServices::DivelogsDeWebServices(QWidget* parent, Qt::WindowFlags f): WebServices(parent, f)
{
	QSettings s;
	ui.userID->setText(s.value("divelogde_user").toString());
	ui.password->setText(s.value("divelogde_pass").toString());
	hideUpload();
}

void DivelogsDeWebServices::startUpload()
{
	ui.status->setText(tr("Uploading dive list..."));
	ui.progressBar->setRange(0,0); // this makes the progressbar do an 'infinite spin'
	ui.upload->setEnabled(false);
	ui.userID->setEnabled(false);
	ui.password->setEnabled(false);

	QNetworkRequest request;
	request.setUrl(QUrl("https://divelogs.de/DivelogsDirectImport.php"));
	request.setRawHeader("Accept", "text/xml, application/xml");

	QHttpPart part;
	part.setRawHeader("Content-Disposition", "form-data; name=\"user\"");
	part.setBody(ui.userID->text().toUtf8());
	multipart->append(part);

	part.setRawHeader("Content-Disposition", "form-data; name=\"pass\"");
	part.setBody(ui.password->text().toUtf8());
	multipart->append(part);

	reply = manager()->post(request, multipart);
	connect(reply, SIGNAL(finished()), this, SLOT(uploadFinished()));
	connect(reply, SIGNAL(error(QNetworkReply::NetworkError)), this,
		SLOT(uploadError(QNetworkReply::NetworkError)));
	connect(reply, SIGNAL(uploadProgress(qint64,qint64)), this,
		SLOT(updateProgress(qint64,qint64)));

	timeout.start(30000); // 30s
}

void DivelogsDeWebServices::startDownload()
{
	ui.status->setText(tr("Downloading dive list..."));
	ui.progressBar->setRange(0,0); // this makes the progressbar do an 'infinite spin'
	ui.download->setEnabled(false);
	ui.userID->setEnabled(false);
	ui.password->setEnabled(false);

	QNetworkRequest request;
	request.setUrl(QUrl("https://divelogs.de/xml_available_dives.php"));
	request.setRawHeader("Accept", "text/xml, application/xml");
	request.setHeader(QNetworkRequest::ContentTypeHeader, "application/x-www-form-urlencoded");

#if QT_VERSION < QT_VERSION_CHECK(5,0,0)
	QUrl body;
	body.addQueryItem("user", ui.userID->text());
	body.addQueryItem("pass", ui.password->text());

	reply = manager()->post(request, body.encodedQuery());
#else
	QUrlQuery body;
	body.addQueryItem("user", ui.userID->text());
	body.addQueryItem("pass", ui.password->text());

	reply = manager()->post(request, body.query(QUrl::FullyEncoded).toLatin1())
#endif
	connect(reply, SIGNAL(finished()), this, SLOT(listDownloadFinished()));
	connect(reply, SIGNAL(error(QNetworkReply::NetworkError)),
		this, SLOT(downloadError(QNetworkReply::NetworkError)));

	timeout.start(30000); // 30s
}

void DivelogsDeWebServices::listDownloadFinished()
{
	if (!reply)
		return;
	QByteArray xmlData = reply->readAll();
	reply->deleteLater();
	reply = NULL;

	// parse the XML data we downloaded
	DiveListResult diveList = parseDiveLogsDeDiveList(xmlData);
	if (!diveList.errorCondition.isEmpty()) {
		// error condition
		resetState();
		ui.status->setText(diveList.errorCondition);
		return;
	}

	ui.status->setText(tr("Downloading %1 dives...").arg(diveList.idCount));

	QNetworkRequest request;
//	request.setUrl(QUrl("https://divelogs.de/DivelogsDirectExport.php"));
	request.setUrl(QUrl("http://divelogs.de/DivelogsDirectExport.php"));
	request.setRawHeader("Accept", "application/zip, */*");
	request.setHeader(QNetworkRequest::ContentTypeHeader, "application/x-www-form-urlencoded");

#if QT_VERSION < QT_VERSION_CHECK(5,0,0)
	QUrl body;
	body.addQueryItem("user", ui.userID->text());
	body.addQueryItem("pass", ui.password->text());
	body.addQueryItem("ids", diveList.idList);

	reply = manager()->post(request, body.encodedQuery());
#else
	QUrlQuery body;
	body.addQueryItem("user", ui.userID->text());
	body.addQueryItem("pass", ui.password->text());
	body.addQueryItem("ids", diveList.idList);

	reply = manager()->post(request, body.query(QUrl::FullyEncoded).toLatin1())
#endif

	connect(reply, SIGNAL(readyRead()), this, SLOT(saveToZipFile()));
	connectSignalsForDownload(reply);
}

void DivelogsDeWebServices::saveToZipFile()
{
	if (!zipFile.isOpen()) {
		zipFile.setFileTemplate(QDir::tempPath() + "/import-XXXXXX.dld");
		zipFile.open();
	}

	zipFile.write(reply->readAll());
}

void DivelogsDeWebServices::downloadFinished()
{
	if (!reply)
		return;

	ui.download->setEnabled(true);
	ui.status->setText(tr("Download finished - %1").arg(reply->attribute(QNetworkRequest::HttpReasonPhraseAttribute).toString()));
	reply->deleteLater();
	reply = NULL;

	int errorcode;
	zipFile.seek(0);
#ifdef Q_OS_UNIX
	int duppedfd = dup(zipFile.handle());
	struct zip *zip = zip_fdopen(duppedfd, 0, &errorcode);
	if (!zip)
		::close(duppedfd);
#else
	struct zip *zip = zip_open(zipFile.fileName().toLocal8Bit().data(), 0, &errorcode);
#endif
	if (!zip) {
		char buf[512];
		zip_error_to_str(buf, sizeof(buf), errorcode, errno);
		QMessageBox::critical(this, tr("Corrupted download"),
				      tr("The archive could not be opened:\n%1").arg(QString::fromLocal8Bit(buf)));
		zipFile.close();
		return;
	}

	quint64 entries = zip_get_num_entries(zip, 0);
	for (quint64 i = 0; i < entries; ++i) {
		struct zip_file *zip_file = zip_fopen_index(zip, i, 0);
		if (!zip_file) {
			QMessageBox::critical(this, tr("Corrupted download"),
					      tr("The archive contains corrupt data:\n%1").arg(QString::fromLocal8Bit(zip_strerror(zip))));
			goto close_zip;
		}

		// ### FIXME: What do I do with this?

		zip_fclose(zip_file);
	}

close_zip:
	zip_close(zip);
	zipFile.close();
}

void DivelogsDeWebServices::uploadFinished()
{
	if (!reply)
		return;

	ui.progressBar->setRange(0,1);
	ui.upload->setEnabled(true);
	ui.status->setText(tr("Upload finished"));

	// check what the server sent us: it might contain
	// an error condition, such as a failed login
	QByteArray xmlData = reply->readAll();

	// ### FIXME: what's the format?
}

void DivelogsDeWebServices::setStatusText(int status)
{

}

void DivelogsDeWebServices::downloadError(QNetworkReply::NetworkError)
{
	resetState();
	ui.status->setText(tr("Download error: %1").arg(reply->errorString()));
	reply->deleteLater();
	reply = NULL;
}

void DivelogsDeWebServices::uploadError(QNetworkReply::NetworkError error)
{
	downloadError(error);
}

void DivelogsDeWebServices::buttonClicked(QAbstractButton* button)
{

}