#include "UnsavedDocumentsDialog.h"
#include <QDialogButtonBox>
#include <QListWidget>
#include <QPushButton>
#include <QVBoxLayout>
#include <QLabel>
#include <algorithm>

UnsavedDocumentsDialog::UnsavedDocumentsDialog(const QList<std::shared_ptr<SqlDocument>> &docs, QWidget *parent)
	: QDialog(parent)
	, m_docs(docs)
	, m_list(new QListWidget(this))
{
	setWindowTitle(tr("Unsaved changes"));

	auto layout = new QVBoxLayout(this);
	layout->addWidget(new QLabel(tr("The following documents have unsaved changes. Select the documents to save or discard:"), this));

	for (const auto &doc : m_docs) {
		QStringList windows;
		for (const QWidget *editor : doc->editors()) {
			QString title = editor->window()->windowTitle();
			if (!windows.contains(title))
				windows.append(title);
		}

		auto item = new QListWidgetItem(QString("%1 (%2)").arg(doc->fileName(), windows.join(", ")), m_list);
		item->setToolTip(doc->fileName());
		item->setFlags(item->flags() | Qt::ItemIsUserCheckable);
		item->setCheckState(Qt::Checked);
	}
	layout->addWidget(m_list);

	auto buttons = new QDialogButtonBox(this);
	auto save_button = buttons->addButton(tr("Save selected"), QDialogButtonBox::AcceptRole);
	auto discard_button = buttons->addButton(tr("Discard selected"), QDialogButtonBox::DestructiveRole);
	buttons->addButton(QDialogButtonBox::Cancel);
	layout->addWidget(buttons);

	connect(save_button, &QPushButton::clicked, this, [this]() {
		m_choice = Choice::Save;
		accept();
	});
	connect(discard_button, &QPushButton::clicked, this, [this]() {
		m_choice = Choice::Discard;
		accept();
	});
	connect(buttons, &QDialogButtonBox::rejected, this, &QDialog::reject);
}

QList<std::shared_ptr<SqlDocument>> UnsavedDocumentsDialog::checkedDocuments() const
{
	QList<std::shared_ptr<SqlDocument>> result;
	for (int i = 0; i < m_docs.size(); ++i) {
		if (m_list->item(i)->checkState() == Qt::Checked)
			result.append(m_docs[i]);
	}
	return result;
}

QList<std::shared_ptr<SqlDocument>> UnsavedDocumentsDialog::uncheckedDocuments() const
{
	QList<std::shared_ptr<SqlDocument>> result;
	for (int i = 0; i < m_docs.size(); ++i) {
		if (m_list->item(i)->checkState() != Qt::Checked)
			result.append(m_docs[i]);
	}
	return result;
}

QList<std::shared_ptr<SqlDocument>> documentsClosedWith(const QList<std::shared_ptr<SqlDocument>> &docs,
	const std::function<bool(const QWidget*)> &isClosing)
{
	QList<std::shared_ptr<SqlDocument>> result;
	for (const auto &doc : docs) {
		const auto &editors = doc->editors();
		if (!doc->isModified() || editors.isEmpty())
			continue;

		bool all_closing = std::all_of(editors.begin(), editors.end(),
			[&isClosing](const QWidget *editor) { return isClosing(editor); });
		if (all_closing)
			result.append(doc);
	}
	return result;
}

bool confirmClose(QWidget *parent, const QList<std::shared_ptr<SqlDocument>> &docs)
{
	auto remaining = docs;
	while (!remaining.isEmpty()) {
		UnsavedDocumentsDialog dlg(remaining, parent);
		if (dlg.exec() != QDialog::Accepted || dlg.choice() == UnsavedDocumentsDialog::Choice::Cancel)
			return false;

		bool save = dlg.choice() == UnsavedDocumentsDialog::Choice::Save;
		for (const auto &doc : dlg.checkedDocuments()) {
			if (save) {
				if (!doc->save(parent))
					return false;
			}
			else {
				doc->setModified(false);
			}
		}

		// Show the dialog again for the documents the user did not select.
		remaining = dlg.uncheckedDocuments();
	}

	return true;
}