// SPDX-License-Identifier: GPL-2.0
#include "qt-models/filtermodels.h"
#include "qt-models/models.h"
#include "core/display.h"
#include "qt-models/divetripmodel.h"

#if !defined(SUBSURFACE_MOBILE)
#include "desktop-widgets/divelistview.h"
#include "desktop-widgets/mainwindow.h"
#endif

#include <QDebug>
#include <algorithm>

#define CREATE_INSTANCE_METHOD( CLASS ) \
CLASS *CLASS::instance() \
{ \
	static CLASS *self = new CLASS(); \
	return self; \
}

#define CREATE_MODEL_SET_DATA_METHOD( CLASS ) \
bool CLASS::setData(const QModelIndex &index, const QVariant &value, int role) \
{ \
	if (role == Qt::CheckStateRole) { \
		checkState[index.row()] = value.toBool(); \
		anyChecked = false; \
		for (int i = 0; i < rowCount(); i++) { \
			if (checkState[i] == true) { \
				anyChecked = true; \
				break; \
			} \
		} \
		dataChanged(index, index); \
		return true; \
	} \
	return false; \
}

#define CREATE_CLEAR_FILTER_METHOD( CLASS ) \
void CLASS::clearFilter() \
{ \
	std::fill(checkState.begin(), checkState.end(), false); \
	anyChecked = false; \
	emit dataChanged(createIndex(0,0), createIndex(rowCount()-1, 0)); \
}

#define CREATE_FLAGS_METHOD( CLASS ) \
Qt::ItemFlags CLASS::flags(const QModelIndex &index) const \
{ \
	return QStringListModel::flags(index) | Qt::ItemIsUserCheckable; \
}

#define CREATE_DATA_METHOD( CLASS, COUNTER_FUNCTION ) \
QVariant CLASS::data(const QModelIndex &index, int role) const \
{ \
	if (role == Qt::CheckStateRole) { \
		return checkState[index.row()] ? Qt::Checked : Qt::Unchecked; \
	} else if (role == Qt::DisplayRole) { \
		QString value = stringList()[index.row()]; \
		int count = COUNTER_FUNCTION((index.row() == rowCount() - 1) ? "" : value.toUtf8().data()); \
		return value + QString(" (%1)").arg(count); \
	} \
	return QVariant(); \
}

#define CREATE_COMMON_METHODS_FOR_FILTER( CLASS, COUNTER_FUNCTION ) \
CREATE_FLAGS_METHOD( CLASS ); \
CREATE_CLEAR_FILTER_METHOD( CLASS ); \
CREATE_MODEL_SET_DATA_METHOD( CLASS ); \
CREATE_INSTANCE_METHOD( CLASS ); \
CREATE_DATA_METHOD( CLASS, COUNTER_FUNCTION )

CREATE_COMMON_METHODS_FOR_FILTER(TagFilterModel, count_dives_with_tag)
CREATE_COMMON_METHODS_FOR_FILTER(BuddyFilterModel, count_dives_with_person)
CREATE_COMMON_METHODS_FOR_FILTER(LocationFilterModel, count_dives_with_location)
CREATE_COMMON_METHODS_FOR_FILTER(SuitsFilterModel, count_dives_with_suit)

CREATE_INSTANCE_METHOD(MultiFilterSortModel)

FilterModelBase::FilterModelBase(QObject *parent) : QStringListModel(parent)
{
}

// Update the stringList and the checkState array.
// The last item is supposed to be the "Show Empty Tags" entry.
void FilterModelBase::updateList(const QStringList &newList)
{
	// Keep copy of old checkState array to reimport them later.
	std::vector<char> oldCheckState = checkState;
	checkState.resize(newList.count());
	std::fill(checkState.begin(), checkState.end(), false);
	anyChecked = false;

	// Ignore last item, since this is the "Show Empty Tags" entry.
	for (int i = 0; i < rowCount() - 1; i++) {
		if (oldCheckState[i]) {
			int ind = newList.indexOf(stringList()[i]);
			if (ind >= 0 && ind < newList.count() - 1) {
				checkState[ind] = true;
				anyChecked = true;
			}
		}
	}

	// On program startup, the old list is empty.
	if (rowCount() > 0 && oldCheckState.back()) {
		checkState.back() = true;
		anyChecked = true;
	}
	setStringList(newList);
}

SuitsFilterModel::SuitsFilterModel(QObject *parent) : FilterModelBase(parent)
{
}

bool SuitsFilterModel::doFilter(dive *d, QModelIndex &index0, QAbstractItemModel *sourceModel) const
{
	Q_UNUSED(index0);
	Q_UNUSED(sourceModel);

	if (!anyChecked) {
		return true;
	}

	// Checked means 'Show', Unchecked means 'Hide'.
	QString suit(d->suit);
	// only show empty suit dives if the user checked that.
	if (suit.isEmpty()) {
		if (rowCount() > 0)
			return checkState[rowCount() - 1];
		else
			return true;
	}

	// there is a suit selected
	QStringList suitList = stringList();
	// Ignore last item, since this is the "Show Empty Tags" entry
	for (int i = 0; i < rowCount() - 1; i++) {
		if (checkState[i] && suit == suitList[i])
			return true;
	}
	return false;
}

void SuitsFilterModel::repopulate()
{
	QStringList list;
	struct dive *dive;
	int i = 0;
	for_each_dive (i, dive) {
		QString suit(dive->suit);
		if (!suit.isEmpty() && !list.contains(suit)) {
			list.append(suit);
		}
	}
	qSort(list);
	list << tr("No suit set");
	updateList(list);
}

TagFilterModel::TagFilterModel(QObject *parent) : FilterModelBase(parent)
{
}

void TagFilterModel::repopulate()
{
	if (g_tag_list == NULL)
		return;
	QStringList list;
	struct tag_entry *current_tag_entry = g_tag_list;
	while (current_tag_entry != NULL) {
		if (count_dives_with_tag(current_tag_entry->tag->name) > 0)
			list.append(QString(current_tag_entry->tag->name));
		current_tag_entry = current_tag_entry->next;
	}
	qSort(list);
	list << tr("Empty tags");
	updateList(list);
}

bool TagFilterModel::doFilter(dive *d, QModelIndex &index0, QAbstractItemModel *sourceModel) const
{
	Q_UNUSED(index0);
	Q_UNUSED(sourceModel);

	// If there's nothing checked, this should show everything
	if (!anyChecked) {
		return true;
	}
	// Checked means 'Show', Unchecked means 'Hide'.
	struct tag_entry *head = d->tag_list;

	if (!head) { // last tag means "Show empty tags";
		if (rowCount() > 0)
			return checkState[rowCount() - 1];
		else
			return true;
	}

	// have at least one tag.
	QStringList tagList = stringList();
	if (!tagList.isEmpty()) {
		tagList.removeLast(); // remove the "Show Empty Tags";
		while (head) {
			QString tagName(head->tag->name);
			int index = tagList.indexOf(tagName);
			if (checkState[index])
				return true;
			head = head->next;
		}
	}
	return false;
}

BuddyFilterModel::BuddyFilterModel(QObject *parent) : FilterModelBase(parent)
{
}

bool BuddyFilterModel::doFilter(dive *d, QModelIndex &index0, QAbstractItemModel *sourceModel) const
{
	Q_UNUSED(index0);
	Q_UNUSED(sourceModel);

	// If there's nothing checked, this should show everything
	if (!anyChecked) {
		return true;
	}
	// Checked means 'Show', Unchecked means 'Hide'.
	QString diveBuddy(d->buddy);
	QString divemaster(d->divemaster);
	// only show empty buddie dives if the user checked that.
	if (diveBuddy.isEmpty() && divemaster.isEmpty()) {
		if (rowCount() > 0)
			return checkState[rowCount() - 1];
		else
			return true;
	}

	// have at least one buddy
	QStringList buddyList = stringList();
	// Ignore last item, since this is the "Show Empty Tags" entry
	for (int i = 0; i < rowCount() - 1; i++) {
		if (checkState[i] && (diveBuddy == buddyList[i] || divemaster == buddyList[i]))
			return true;
	}
	return false;
}

void BuddyFilterModel::repopulate()
{
	QStringList list;
	struct dive *dive;
	int i = 0;
	for_each_dive (i, dive) {
		QString persons = QString(dive->buddy) + "," + QString(dive->divemaster);
		Q_FOREACH (const QString &person, persons.split(',', QString::SkipEmptyParts)) {
			// Remove any leading spaces
			if (!list.contains(person.trimmed())) {
				list.append(person.trimmed());
			}
		}
	}
	qSort(list);
	list << tr("No buddies");
	updateList(list);
}

LocationFilterModel::LocationFilterModel(QObject *parent) : FilterModelBase(parent)
{
}

bool LocationFilterModel::doFilter(struct dive *d, QModelIndex &index0, QAbstractItemModel *sourceModel) const
{
	Q_UNUSED(index0);
	Q_UNUSED(sourceModel);

	if (!anyChecked) {
		return true;
	}
	// Checked means 'Show', Unchecked means 'Hide'.
	QString location(get_dive_location(d));
	// only show empty location dives if the user checked that.
	if (location.isEmpty()) {
		if (rowCount() > 0)
			return checkState[rowCount() - 1];
		else
			return true;
	}

	// There is a location selected
	QStringList locationList = stringList();
	// Ignore last item, since this is the "Show Empty Tags" entry
	for (int i = 0; i < rowCount() - 1; i++) {
		if (checkState[i] && location == locationList[i])
			return true;
	}
	return false;
}

void LocationFilterModel::repopulate()
{
	QStringList list;
	struct dive *dive;
	int i = 0;
	for_each_dive (i, dive) {
		QString location(get_dive_location(dive));
		if (!location.isEmpty() && !list.contains(location)) {
			list.append(location);
		}
	}
	qSort(list);
	list << tr("No location set");
	updateList(list);
}

void LocationFilterModel::changeName(const QString &oldName, const QString &newName)
{
	if (oldName.isEmpty() || newName.isEmpty() || oldName == newName)
		return;
	QStringList list = stringList();
	int oldIndex = list.indexOf(oldName);
	if (oldIndex < 0)
		return;
	int newIndex = list.indexOf(newName);
	list[oldIndex] = newName;
	setStringList(list);

	// If there was already an entry with the new name, we are merging entries.
	// Thus, if the old entry was selected, also select the new entry.
	if (newIndex >= 0 && checkState[oldIndex])
		checkState[newIndex] = true;
}

void LocationFilterModel::addName(const QString &newName)
{
	// If any item is checked and a new location is added, add the name
	// of the new location in front of the list and mark it as checked.
	// Thus, on subsequent repopulation of the list, the new entry will
	// be registered as already checked.
	QStringList list = stringList();
	if (!anyChecked || newName.isEmpty() || list.indexOf(newName) >= 0)
		return;
	list.prepend(newName);
	setStringList(list);
	checkState.insert(checkState.begin(), true);
}

MultiFilterSortModel::MultiFilterSortModel(QObject *parent) :
	QSortFilterProxyModel(parent),
	divesDisplayed(0),
	justCleared(false),
	curr_dive_site(NULL)
{
}

bool MultiFilterSortModel::filterAcceptsRow(int source_row, const QModelIndex &source_parent) const
{
	bool shouldShow = true;
	QModelIndex index0 = sourceModel()->index(source_row, 0, source_parent);
	QVariant diveVariant = sourceModel()->data(index0, DiveTripModel::DIVE_ROLE);
	struct dive *d = (struct dive *)diveVariant.value<void *>();

	if (curr_dive_site) {
		struct dive_site *ds = NULL;
		if (!d) { // It's a trip, only show the ones that have dives to be shown.
			bool showTrip = false;
			for (int i = 0; i < sourceModel()->rowCount(index0); i++) {
				QModelIndex child = sourceModel()->index(i, 0, index0);
				d = (struct dive *) sourceModel()->data(child, DiveTripModel::DIVE_ROLE).value<void*>();
				ds = get_dive_site_by_uuid(d->dive_site_uuid);
				if (!ds)
					continue;
				if ( same_string(ds->name, curr_dive_site->name) || ds->uuid == curr_dive_site->uuid) {
					if (ds->uuid != curr_dive_site->uuid) {
						qWarning() << "Warning, two different dive sites with same name have a different id"
							<< ds->uuid << "and" << curr_dive_site->uuid;
					}
					showTrip = true; // do not shortcircuit the loop or the counts will be wrong
				}
			}
			return showTrip;
		}
		ds = get_dive_site_by_uuid(d->dive_site_uuid);
		if (!ds)
			return false;
		return ( same_string(ds->name, curr_dive_site->name) || ds->uuid == curr_dive_site->uuid);
	}

	if (justCleared || models.isEmpty())
		return true;

	if (!d) { // It's a trip, only show the ones that have dives to be shown.
		bool showTrip = false;
		for (int i = 0; i < sourceModel()->rowCount(index0); i++) {
			if (filterAcceptsRow(i, index0))
				showTrip = true; // do not shortcircuit the loop or the counts will be wrong
		}
		return showTrip;
	}
	Q_FOREACH (MultiFilterInterface *model, models) {
		if (!model->doFilter(d, index0, sourceModel()))
			shouldShow = false;
	}

	filter_dive(d, shouldShow);
	return shouldShow;
}

void MultiFilterSortModel::myInvalidate()
{
#if !defined(SUBSURFACE_MOBILE)
	int i;
	struct dive *d;
	DiveListView *dlv = MainWindow::instance()->dive_list();

	divesDisplayed = 0;

	invalidate();

	// first make sure the trips are no longer shown as selected
	// (but without updating the selection state of the dives... this just cleans
	//  up an oddity in the filter handling)
	// TODO: This should go internally to DiveList, to be triggered after a filter is due.
	dlv->clearTripSelection();

	// if we have no more selected dives, clean up the display - this later triggers us
	// to pick one of the dives that are shown in the list as selected dive which is the
	// natural behavior
	if (amount_selected == 0) {
		MainWindow::instance()->cleanUpEmpty();
	} else {
		// otherwise find the dives that should still be selected (the filter above unselected any
		// dive that's no longer visible) and select them again
		QList<int> curSelectedDives;
		for_each_dive (i, d) {
			if (d->selected)
				curSelectedDives.append(get_divenr(d));
		}
		dlv->selectDives(curSelectedDives);
	}

	for_each_dive (i,d) {
		if (!d->hidden_by_filter)
			divesDisplayed++;
	}

	emit filterFinished();

	if (curr_dive_site) {
		dlv->expandAll();
	}
#endif
}

void MultiFilterSortModel::addFilterModel(MultiFilterInterface *model)
{
	QAbstractItemModel *itemModel = dynamic_cast<QAbstractItemModel *>(model);
	Q_ASSERT(itemModel);
	models.append(model);
	connect(itemModel, SIGNAL(dataChanged(QModelIndex, QModelIndex)), this, SLOT(myInvalidate()));
}

void MultiFilterSortModel::removeFilterModel(MultiFilterInterface *model)
{
	QAbstractItemModel *itemModel = dynamic_cast<QAbstractItemModel *>(model);
	Q_ASSERT(itemModel);
	models.removeAll(model);
	disconnect(itemModel, SIGNAL(dataChanged(QModelIndex, QModelIndex)), this, SLOT(myInvalidate()));
}

void MultiFilterSortModel::clearFilter()
{
	justCleared = true;
	Q_FOREACH (MultiFilterInterface *iface, models) {
		iface->clearFilter();
	}
	justCleared = false;
	myInvalidate();
}

void MultiFilterSortModel::startFilterDiveSite(uint32_t uuid)
{
	curr_dive_site = get_dive_site_by_uuid(uuid);
	myInvalidate();
}

void MultiFilterSortModel::stopFilterDiveSite()
{
	curr_dive_site = NULL;
	myInvalidate();
}