#include "querytab.h"
#include "ui_querytab.h"

#include "sqlhighlighter.h"

#include <QStandardPaths>
#include <QFileDialog>
#include <QMessageBox>
#include <QTabWidget>
#include <QTextCodec>
#include <QTextDocumentFragment>
#include <QTextStream>
#include "explaintreemodelitem.h"
#include "json/json.h"
#include "mainwindow.h"
#include "util.h"

QueryTab::QueryTab(MainWindow *win, QWidget *parent) :
	QWidget(parent),
	ui(new Ui::QueryTab),
	m_win(win)
{
	ui->setupUi(this);

	m_dbConnection.setStateCallback([this](ASyncDBConnection::State st)
		{
			m_win->QueueTask([this, st]() { connectionStateChanged(st); });
		});

	m_dbConnection.setNoticeCallback([this](Pgsql::ErrorDetails details)
		{
			m_win->QueueTask([this, details]() { receiveNotice(details); });
		});

	QFont font;
	font.setFamily("Source Code Pro");
	font.setFixedPitch(true);
	font.setPointSize(10);
	ui->queryEdit->setFont(font);
	highlighter.reset(new SqlHighlighter(ui->queryEdit->document()));

	connect(ui->queryEdit, &QPlainTextEdit::textChanged, this, &QueryTab::queryTextChanged);
//	m_stopwatch.setOutputLabel(ui->lblElapsedTime);
//	ui->lblElapsedTime->clear();
//	ui->lblRowCount->clear();
}

QueryTab::~QueryTab()
{
	m_dbConnection.closeConnection();
	m_dbConnection.setStateCallback(nullptr);
	delete ui;
}

void QueryTab::setConfig(const ConnectionConfig &config)
{
	m_config = config;
//	QString title = "pglab - ";
//	title += m_config.name().c_str();
//	setWindowTitle(title);
	m_win->QueueTask([this]() { startConnect(); });
}

bool QueryTab::canClose()
{
	bool can_close;
	if (m_queryTextChanged) {
		can_close = continueWithoutSavingWarning();
	}
	else {
		can_close = true;
	}
	return can_close;
}

//void QueryTab::open()
//{
//	if (m_queryTextChanged && !continueWithoutSavingWarning()) {
//		return;
//	}

//	QString home_dir = QStandardPaths::locate(QStandardPaths::HomeLocation, "", QStandardPaths::LocateDirectory);
//	QString file_name = QFileDialog::getOpenFileName(this,
//		tr("Open sql query"), home_dir, tr("SQL files (*.sql *.txt)"));
//	if ( ! file_name.isEmpty()) {
//		QFile file(file_name);
//		if (file.open(QIODevice::ReadWrite)) {
//			QTextStream stream(&file);
//			ui->queryEdit->clear();
//			while (!stream.atEnd()){
//				QString line = stream.readLine();
//				ui->queryEdit->appendPlainText(line);
//			}
//			m_queryTextChanged = false;
//			setFileName(file_name);
//		}
//	}
//}

void QueryTab::newdoc()
{
	ui->queryEdit->clear();
	setFileName(QString());
	m_queryTextChanged = false;
}

bool QueryTab::load(const QString &filename)
{
	bool result = false;
	QFile file(filename);
	if (file.open(QIODevice::ReadOnly)) {
		QByteArray ba = file.readAll();
		const char *ptr = ba.constData();

		QTextCodec *codec = QTextCodec::codecForUtfText(ba, QTextCodec::codecForName("utf-8"));
		QTextCodec::ConverterState state;
		QString text = codec->toUnicode(ptr, ba.size(), &state);
		if (state.invalidChars > 0) {
			file.reset();
			QTextStream stream(&file);
			text = stream.readAll();
		}

		ui->queryEdit->setPlainText(text);
		m_queryTextChanged = false;
		setFileName(filename);
		result = true;
	}
	return result;
}

void QueryTab::save()
{
	if (m_fileName.isEmpty()) {
		saveAs();
	}
	else {
		saveSqlTo(m_fileName);
	}
}

void QueryTab::saveAs()
{
	QString filename = promptUserForSaveSqlFilename();
	if (!filename.isEmpty()) {
		saveSqlTo(filename);
		setFileName(filename);
	}
}

void QueryTab::saveCopyAs()
{
	QString filename = promptUserForSaveSqlFilename();
	if (!filename.isEmpty()) {
		saveSqlTo(filename);
	}
}

void QueryTab::execute()
{
	if (m_dbConnection.state() == ASyncDBConnection::State::Connected) {
		addLog("Query clicked");

		clearResult();
		ui->messagesEdit->clear();

		std::string cmd = getCommand();
		m_stopwatch.start();
		m_dbConnection.send(cmd,
			[this](std::shared_ptr<Pgsql::Result> res, qint64 elapsedms)
			{
				m_win->QueueTask([this, res, elapsedms]() { query_ready(res, elapsedms); });
			});
	}
}

void QueryTab::explain(bool analyze)
{
	ui->explainTreeView->setModel(nullptr);
	explainModel.reset();
	ui->messagesEdit->clear();

	addLog("Explain clicked");

	std::string analyze_str;
	if (analyze) {
		analyze_str = "ANALYZE, ";
	}
	m_stopwatch.start();
	std::string cmd = "EXPLAIN (" + analyze_str + "VERBOSE, BUFFERS, FORMAT JSON) " + getCommand();
	m_dbConnection.send(cmd,
		[this](std::shared_ptr<Pgsql::Result> res, qint64 )
		{
			if (res) {
				// Process explain data seperately
				std::thread([this,res]()
				{
					std::shared_ptr<ExplainRoot> explain;
					if (res->getCols() == 1 && res->getRows() == 1) {
						std::string s = res->getVal(0, 0);
						Json::Value root;   // will contains the root value after parsing.
						Json::Reader reader;
						bool parsingSuccessful = reader.parse(s, root);
						if (parsingSuccessful) {
							explain = ExplainRoot::createFromJson(root);
						}
					}
					m_win->QueueTask([this, explain]() { explain_ready(explain); });
				}).detach();
			}
		});
}

void QueryTab::cancel()
{
	m_dbConnection.cancel();
}


void QueryTab::setFileName(const QString &filename)
{
	m_fileName = filename;
	QFileInfo fileInfo(filename);
	QString fn(fileInfo.fileName());
	setTabCaption(fn, m_fileName);
}

bool QueryTab::continueWithoutSavingWarning()
{
	QMessageBox msgBox;
	msgBox.setIcon(QMessageBox::Warning);
	msgBox.setText("The document has been modified.");
	msgBox.setInformativeText("The current query has unsaved changes, do you want to continue without saving those changes?");
	msgBox.setStandardButtons(QMessageBox::Yes | QMessageBox::No);
	msgBox.setDefaultButton(QMessageBox::No);
	int ret = msgBox.exec();
	return ret == QMessageBox::Yes;
}

bool QueryTab::saveSqlTo(const QString &filename)
{
	bool result = false;
	QFile file(filename);
	if (file.open(QIODevice::WriteOnly)) {
		QTextStream stream(&file);
		stream.setCodec("utf-8");
		QString text = ui->queryEdit->toPlainText();
		stream << text;
/*


		QTextDocument *doc = ui->queryEdit->document();
		QTextBlock block = doc->firstBlock();
		while (stream.status() == QTextStream::Ok && block.isValid()) {
			QString plain = block.text();
			stream << plain << "\n";
			block = block.next();
		}*/

		if (stream.status() == QTextStream::Ok) {
			m_queryTextChanged = false;
			result = true;
		}
	}
	return result;
}

QString QueryTab::promptUserForSaveSqlFilename()
{
	QString home_dir = QStandardPaths::locate(QStandardPaths::HomeLocation, "", QStandardPaths::LocateDirectory);
	return QFileDialog::getSaveFileName(this, tr("Save query"), home_dir, tr("SQL file (*.sql)"));
}

void QueryTab::queryTextChanged()
{
	m_queryTextChanged = true;
}


void QueryTab::connectionStateChanged(ASyncDBConnection::State state)
{
	QString status_str;
	switch (state) {
	case ASyncDBConnection::State::NotConnected:
		status_str = tr("Geen verbinding");
		break;
	case ASyncDBConnection::State::Connecting:
		status_str = tr("Verbinden");
		break;
	case ASyncDBConnection::State::Connected:
		status_str = tr("Verbonden");
		break;
	case ASyncDBConnection::State::QuerySend:
		status_str = tr("Query verstuurd");
		break;
	case ASyncDBConnection::State::CancelSend:
		status_str = tr("Query geannuleerd");
		break;
	}
	addLog(status_str);
//	statusBar()->showMessage(status_str);

//	bool connected = ASyncDBConnection::State::Connected == state;
//	ui->actionExecute_SQL->setEnabled(connected);
//	ui->actionExplain_Analyze->setEnabled(connected);
//	ui->actionCancel->setEnabled(ASyncDBConnection::State::QuerySend == state);
}


void QueryTab::addLog(QString s)
{
	QTextCursor text_cursor = QTextCursor(ui->edtLog->document());
	text_cursor.movePosition(QTextCursor::End);
	text_cursor.insertText(s + "\r\n");
}

void QueryTab::receiveNotice(Pgsql::ErrorDetails notice)
{
	ui->messagesEdit->append(QString::fromStdString(notice.errorMessage));

	ui->messagesEdit->append(QString::fromStdString(notice.severity));
	ui->messagesEdit->append(QString("At position: %1").arg(notice.statementPosition));
	ui->messagesEdit->append(QString::fromStdString("State: " + notice.state));
	ui->messagesEdit->append(QString::fromStdString("Primary: " + notice.messagePrimary));
	ui->messagesEdit->append(QString::fromStdString("Detail: " + notice.messageDetail));
	ui->messagesEdit->append(QString::fromStdString("Hint: " + notice.messageHint));
	ui->messagesEdit->append(QString::fromStdString("Context: " + notice.context));
//	std::string state; ///< PG_DIAG_SQLSTATE Error code as listed in	https://www.postgresql.org/docs/9.5/static/errcodes-appendix.html
//	std::string severity;
//	std::string messagePrimary;
//	std::string messageDetail;
//	std::string messageHint;
//	int statementPosition; ///< First character is one, measured in characters not bytes!
	//	std::string context;

//	int internalPosition;
//	std::string internalQuery;
//	std::string schemaName;
//	std::string tableName;
//	std::string columnName;
//	std::string datatypeName;
//	std::string constraintName;
//	std::string sourceFile;
//	std::string sourceLine;
//	std::string sourceFunction;

//	QTextCursor cursor = ui->messagesEdit->textCursor();
//	cursor.movePosition(QTextCursor::End, QTextCursor::MoveAnchor);

//	QTextTable *table = cursor.insertTable(4, 2);
//	if (table) {
//		table->cellAt(1, 0).firstCursorPosition().insertText("State");
//		table->cellAt(1, 1).firstCursorPosition().insertText(QString::fromStdString(notice.state));
//		table->cellAt(2, 0).firstCursorPosition().insertText("Primary");
//		table->cellAt(2, 1).firstCursorPosition().insertText(QString::fromStdString(notice.messagePrimary));
//		table->cellAt(3, 0).firstCursorPosition().insertText("Detail");
//		table->cellAt(3, 1).firstCursorPosition().insertText(QString::fromStdString(notice.messageDetail));
//	}

	// syntax error at or near "limit
	// statementPosition
}

void QueryTab::startConnect()
{
	m_dbConnection.setupConnection(m_config);
}

void QueryTab::explain_ready(ExplainRoot::SPtr explain)
{
	m_stopwatch.stop();
	if (explain) {
		addLog("Explain ready");
		QString times_str = QString("Execution time: %1, Planning time: %2")
						.arg(
					msfloatToHumanReadableString(explain->executionTime)
					, msfloatToHumanReadableString(explain->planningTime));
		ui->lblTimes->setText(times_str);
		explainModel.reset(new QueryExplainModel(nullptr, explain));
		ui->explainTreeView->setModel(explainModel.get());
		ui->explainTreeView->expandAll();
		ui->explainTreeView->setColumnWidth(0, 200);
		ui->explainTreeView->setColumnWidth(1, 80);
		ui->explainTreeView->setColumnWidth(2, 80);
		ui->explainTreeView->setColumnWidth(3, 80);
		ui->explainTreeView->setColumnWidth(4, 80);
		ui->explainTreeView->setColumnWidth(5, 80);
		ui->explainTreeView->setColumnWidth(6, 600);
		ui->tabWidget->setCurrentWidget(ui->explainTab);
//		statusBar()->showMessage(tr("Explain ready."));
	}
	else {
		addLog("Explain no result");
		ui->tabWidget->setCurrentWidget(ui->messageTab);
//		statusBar()->showMessage(tr("Explain failed."));
	}
}

std::string QueryTab::getCommand() const
{
	QString command;
	QTextCursor cursor = ui->queryEdit->textCursor();
	if (cursor.hasSelection()) {
		command = cursor.selection().toPlainText();
	}
	else {
		command = ui->queryEdit->toPlainText();
	}
	return command.toUtf8().data();
}

void QueryTab::setTabCaption(const QString &caption, const QString &tooltip)
{
	QWidget * w = parentWidget();
	QWidget * p = w->parentWidget();
	QTabWidget *tabwidget = dynamic_cast<QTabWidget*>(p);
	if (tabwidget) {
		int i = tabwidget->indexOf(this);
		if (i >= 0) {
			tabwidget->setTabText(i, caption);
			tabwidget->setTabToolTip(i, tooltip);
		}
	}

}

void QueryTab::query_ready(std::shared_ptr<Pgsql::Result> dbres, qint64 elapsedms)
{
	if (dbres) {
		addLog("query_ready with result");
		auto st = dbres->resultStatus();
		if (st == PGRES_TUPLES_OK) {
			//int n_rows = dbres->getRows();
			//QString rowcount_str = QString("rows: %1").arg(dbres->getRows());

			auto result_model = std::make_shared<QueryResultModel>(nullptr , dbres);
			TuplesResultWidget *trw = new TuplesResultWidget;
			trw->setResult(result_model, elapsedms);
			resultList.push_back(trw);
			ui->tabWidget->addTab(trw, "Data");
//			ui->lblRowCount->setText(rowcount_str);
//			resultModel.reset(new QueryResultModel(nullptr , dbres));
//			ui->ResultView->setModel(resultModel.get());
//			ui->tabWidget->setCurrentWidget(ui->dataTab);
			//statusBar()->showMessage(tr("Query ready."));
		}
		else {
			if (st == PGRES_COMMAND_OK) {
//				statusBar()->showMessage(tr("Command OK."));
				int tuples_affected = dbres->tuplesAffected();
				QString msg;
				if (tuples_affected >= 0)
					msg = tr("Query returned succesfully: %1 rows affected, execution time %2")
						.arg(QString::number(tuples_affected))
						.arg(msfloatToHumanReadableString(elapsedms));
				else
					msg = tr("Query returned succesfully, execution time %1")
						.arg(msfloatToHumanReadableString(elapsedms));

				ui->messagesEdit->append(msg);

				ui->tabWidget->setCurrentWidget(ui->messageTab);
			}
			else {
//				if (st == PGRES_EMPTY_QUERY) {
//					statusBar()->showMessage(tr("Empty query."));
//				}
//				else if (st == PGRES_COPY_OUT) {
//					statusBar()->showMessage(tr("COPY OUT."));
//				}
//				else if (st == PGRES_COPY_IN) {
//					statusBar()->showMessage(tr("COPY IN."));
//				}
//				else if (st == PGRES_BAD_RESPONSE) {
//					statusBar()->showMessage(tr("BAD RESPONSE."));
//				}
//				else if (st == PGRES_NONFATAL_ERROR) {
//					statusBar()->showMessage(tr("NON FATAL ERROR."));
//				}
//				else if (st == PGRES_FATAL_ERROR) {
//					statusBar()->showMessage(tr("FATAL ERROR."));
//				}
//				else if (st == PGRES_COPY_BOTH) {
//					statusBar()->showMessage(tr("COPY BOTH shouldn't happen is for replication."));
//				}
//				else if (st == PGRES_SINGLE_TUPLE) {
//					statusBar()->showMessage(tr("SINGLE TUPLE result."));
//				}
//				else {
//					statusBar()->showMessage(tr("No tuples returned, possibly an error..."));
//				}
				ui->tabWidget->setCurrentWidget(ui->messageTab);
				receiveNotice(dbres->diagDetails());
			}
		}
	}
	else {
		m_stopwatch.stop();
		addLog("query_ready with NO result");
//		statusBar()->showMessage(tr("Query cancelled."));
	}
}

void QueryTab::clearResult()
{
//	ui->ResultView->setModel(nullptr);
//	resultModel.reset();
	for (auto e : resultList)
		delete e;
	resultList.clear();
//	ui->lblRowCount->clear();
}