#include <QSqlQuery>
#include <QFileInfo>
#include <QDateTime>
#include <QSqlError>
#include "sqlitedbservice.h"
#include "filedata.h"
#include "logger.h"
bool SqliteDbService::fileExistsInDatabase(QString path, qint64 mtime)
{
	auto query = QSqlQuery("SELECT 1 FROM file WHERE path = ? and mtime = ?", dbFactory->forCurrentThread());
	query.addBindValue(path);
	query.addBindValue(mtime);
	if(!query.exec())
	{
		throw QSSGeneralException("Error while trying to query for file existance: " + query.lastError().text());
	}
	if(!query.next())
	{
		return false;
	}
	return query.value(0).toBool();
}

QVector<SearchResult> SqliteDbService::search(const QSSQuery &query)
{
	auto connection = dbFactory->forCurrentThread();
	SqliteSearch searcher(connection);
	return searcher.search(query);
}

bool SqliteDbService::fileExistsInDatabase(QString path)
{
	auto query = QSqlQuery(dbFactory->forCurrentThread());
	query.prepare("SELECT 1 FROM file WHERE path = ?");
	query.addBindValue(path);
	if(!query.exec())
	{
		throw QSSGeneralException("Error while trying to query for file existance: " + query.lastError().text());
	}
	if(!query.next())
	{
		return false;
	}
	return query.value(0).toBool();
}

SqliteDbService::SqliteDbService(DatabaseFactory &dbFactory)
{
	this->dbFactory = &dbFactory;
}

bool SqliteDbService::deleteFile(QString path)
{
	QSqlQuery query(this->dbFactory->forCurrentThread());
	query.prepare("DELETE FROM file WHERE path = ?");
	query.addBindValue(path);
	bool result = query.exec();
	if(!result)
	{
		Logger::error() << "Failed to delete file" << path << endl;
	}
	return result;
}
int SqliteDbService::getFiles(QVector<FileData> &results, QString wildCardPattern, int offset, int limit)
{

	int processedRows = 0;
	// TODO: translate/convert wildCardPattern to SQL where instead of regex
	QString sql = "SELECT path, mtime, size, filetype FROM file";

	if(limit != 0)
	{
		sql += " LIMIT " + QString::number(limit);
	}
	if(offset != 0)
	{
		sql += " OFFSET " + QString::number(offset);
	}

	auto query = QSqlQuery(dbFactory->forCurrentThread());
	query.prepare(sql);
	query.setForwardOnly(true);
	if(!query.exec())
	{
		throw QSSGeneralException("Error while trying to retrieve files from database: " + query.lastError().text());
	}

	// TODO: port this to QRegularExpression once >5.12 gets more widespread because of this bug
	// https://bugreports.qt.io/browse/QTBUG-72539?focusedCommentId=439053&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel
	bool usePattern = !wildCardPattern.isEmpty();
	QRegExp regexPattern(wildCardPattern);
	regexPattern.setPatternSyntax(QRegExp::PatternSyntax::WildcardUnix);

	while(query.next())
	{
		QString absPath = query.value(0).toString();
		if(!usePattern || regexPattern.exactMatch(absPath))
		{
			FileData current;
			current.absPath = absPath;
			current.mtime = query.value(1).toInt();
			current.size = query.value(2).toInt();
			current.filetype = query.value(3).toChar();
			results.append(current);
		}
		++processedRows;
	}
	return processedRows;
}

SaveFileResult SqliteDbService::saveFile(QFileInfo fileInfo, QVector<PageData> &pageData)
{
	QString absPath = fileInfo.absoluteFilePath();
	auto mtime = fileInfo.lastModified().toSecsSinceEpoch();
	QChar fileType = fileInfo.isDir() ? 'd' : 'f';

	QSqlDatabase db = dbFactory->forCurrentThread();
	QSqlQuery delQuery(db);
	delQuery.prepare("DELETE FROM file WHERE path = ?");
	delQuery.addBindValue(absPath);

	QSqlQuery inserterQuery(db);
	inserterQuery.prepare("INSERT INTO file(path, mtime, size, filetype) VALUES(?, ?, ?, ?)");
	inserterQuery.addBindValue(absPath);
	inserterQuery.addBindValue(mtime);
	inserterQuery.addBindValue(fileInfo.size());
	inserterQuery.addBindValue(fileType);

	if(!db.transaction())
	{
		Logger::error() << "Failed to open transaction for " << absPath << " : " << db.lastError() << endl;
		return DBFAIL;
	}

	if(!delQuery.exec())
	{
		Logger::error() << "Failed DELETE query" << delQuery.lastError() << endl;
		db.rollback();
		return DBFAIL;
	}

	if(!inserterQuery.exec())
	{
		Logger::error() << "Failed INSERT query" << inserterQuery.lastError() << endl;
		db.rollback();
		return DBFAIL;
	}

	int lastid = inserterQuery.lastInsertId().toInt();
	for(const PageData &data : pageData)
	{
		QSqlQuery contentQuery(db);
		contentQuery.prepare("INSERT INTO content(fileid, page, content) VALUES(?, ?, ?)");
		contentQuery.addBindValue(lastid);
		contentQuery.addBindValue(data.pagenumber);
		contentQuery.addBindValue(data.content);
		if(!contentQuery.exec())
		{
			db.rollback();
			Logger::error() << "Failed content insertion " << contentQuery.lastError() << endl;
			return DBFAIL;
		}
	}

	if(!db.commit())
	{
		db.rollback();
		Logger::error() << "Failed to commit transaction for " << absPath << " : " << db.lastError() << endl;
		return DBFAIL;
	}
	return OK;
}