#include <QCommandLineParser>
#include <QFile>
#include <QFileInfo>
#include <QDebug>
#include <QRegularExpression>
#include <QSqlError>
#include "commanddelete.h"

int CommandDelete::removeNonExistent(QSqlDatabase &db, bool verbose, bool dryRun, QString pattern)
{

	// 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

	// QRegularExpression regexPattern = QRegularExpression::wildcardToRegularExpression(pattern
	bool usePattern = !pattern.isEmpty();
	QRegExp regexPattern(pattern);
	regexPattern.setPatternSyntax(QRegExp::PatternSyntax::WildcardUnix);

	// TODO: try to translate pattern to SQL WHERE statement
	QSqlQuery pathsQuery("SELECT path FROM file", db);
	if(!pathsQuery.exec())
	{
		Utils::error() << "Failed to query current paths" << endl;
		return 1;
	}

	while(pathsQuery.next())
	{
		QString path = pathsQuery.value(0).toString();
		bool removeFile = true;
		if(usePattern)
		{
			removeFile = regexPattern.exactMatch(path);
		}
		if(removeFile)
		{
			QFile file(path);
			if(!file.exists())
			{
				if(!dryRun)
				{
					QSqlQuery query("DELETE FROM file WHERE path = ?", db);
					query.addBindValue(path);
					if(!query.exec())
					{
						Utils::error() << "Failed to delete " << path << query.lastError() << endl;
						return 1;
					}
					if(verbose)
					{
						Utils::info() << "Deleted " << path << endl;
					}
				}
				else
				{
					Utils::info() << "Would delete " << path << endl;
				}
			}
		}
	}
}

int CommandDelete::removePaths(const QStringList &paths, QSqlDatabase &db, bool verbose, bool dryRun)
{
	int result = 0;
	for(const QString &file : paths)
	{
		QFileInfo fileInfo(file);
		QString absPath = fileInfo.absoluteFilePath();
		if(fileExistsInDatabase(db, absPath))
		{
			if(!dryRun)
			{
				QSqlQuery deletionQuery("DELETE FROM file WHERE path = ?", db);
				deletionQuery.addBindValue(absPath);
				if(deletionQuery.exec())
				{
					if(verbose)
					{
						Utils::info() << "Deleted" << absPath << endl;
					}
				}
				else
				{
					Utils::error() << "Failed to delete:" << absPath << deletionQuery.lastError() << endl;
					result = 1;
				}
			}
		}
		else
		{
			Utils::error() << "No such file in database:" << absPath << endl;
			result = 1;
		}
	}
	return result;
}
int CommandDelete::handle(QStringList arguments)
{
	QCommandLineParser parser;
	parser.addOptions(
		{{{"v", "verbose"}, "Print path of the files while deleting them"},
		 {{"n", "dry-run"}, "Only print which files would be deleted from the database, don't delete them"},
		 {"pattern",
		  "Only delete files from index matching the pattern, e. g. */.git/*. Only applies to --deleted or standalone.",
		  "pattern"},
		 {"deleted", "Delete all files from the index that don't exist anymore"}});

	parser.addHelpOption();
	parser.addPositionalArgument("delete", "Delete paths from the index", "delete [paths...]");

	parser.process(arguments);
	bool verbose = parser.isSet("verbose");
	bool dryRun = parser.isSet("dry-run");
	QString pattern = parser.value("pattern");
	QSqlDatabase db = dbConnection();

	if(parser.isSet("deleted"))
	{

		int result = removeNonExistent(db, verbose, dryRun, pattern);
		if(result != 0)
		{
			return result;
		}
	}

	QStringList files = parser.positionalArguments();
	int result = removePaths(files, db, verbose, dryRun);
	if(result != 0)
	{
		return result;
	}

	return 0;
}