// SPDX-License-Identifier: GPL-2.0
#include "maplocationmodel.h"
#include "divelocationmodel.h"
#include "core/divesite.h"
#include "core/divefilter.h"
#include "core/divelog.h"
#include "core/range.h"
#include "core/settings/qPrefDisplay.h"
#if !defined(SUBSURFACE_MOBILE) && !defined(SUBSURFACE_DOWNLOADER)
#include "qt-models/filtermodels.h"
#include "desktop-widgets/mapwidget.h"
#endif
#include <map>

#define MIN_DISTANCE_BETWEEN_DIVE_SITES_M 50.0

// MKW If "Map Short Names" preference is set, only return the last component
// of the full dive site name.
// Example:
// Japan/Izu Peninsula/Atami/Chinsen-Aft
//    Short name: Chinsen-Aft
static QString siteMapDisplayName(const std::string &sitename)
{
	const char Separator = '/';
	QString fullname = QString::fromStdString(sitename);

	if (!qPrefDisplay::map_short_names() )
		return fullname;

	QString name = fullname.section(Separator, -1).trimmed();
	if (name.isEmpty())
		name = std::move(fullname);
	return name;
}


MapLocation::MapLocation(struct dive_site *dsIn, QGeoCoordinate coordIn, QString nameIn, bool selectedIn) :
    divesite(dsIn), coordinate(coordIn), name(nameIn), selected(selectedIn)
{
}

// Check whether we are in divesite-edit mode. This doesn't
// exist on mobile. And on desktop we have to access the MapWidget.
// Simplify this!
static bool inEditMode()
{
#if defined(SUBSURFACE_MOBILE) || defined(SUBSURFACE_DOWNLOADER)
	return false;
#else
	return MapWidget::instance()->editMode();
#endif
}

QVariant MapLocation::getRole(int role) const
{
	switch (role) {
	case RoleDivesite:
		return QVariant::fromValue(divesite);
	case RoleCoordinate:
		return QVariant::fromValue(coordinate);
	case RoleName:
		return QVariant::fromValue(name);
	case RolePixmap:
		return selected ? QString("qrc:///dive-location-marker-selected-icon") :
		       inEditMode() ? QString("qrc:///dive-location-marker-inactive-icon") :
				    QString("qrc:///dive-location-marker-icon");
	case RoleZ:
		return selected ? 1 : 0;
	case RoleIsSelected:
		return QVariant::fromValue(selected);
	default:
		return QVariant();
	}
}

MapLocationModel::MapLocationModel(QObject *parent) : QAbstractListModel(parent)
{
	connect(&diveListNotifier, &DiveListNotifier::diveSiteChanged, this, &MapLocationModel::diveSiteChanged);
}

MapLocationModel::~MapLocationModel()
{
}

QVariant MapLocationModel::data(const QModelIndex & index, int role) const
{
	if (index.row() < 0 || index.row() >= (int)m_mapLocations.size())
		return QVariant();

	return m_mapLocations[index.row()].getRole(role);
}

QHash<int, QByteArray> MapLocationModel::roleNames() const
{
	QHash<int, QByteArray> roles;
	roles[MapLocation::RoleDivesite] = "divesite";
	roles[MapLocation::RoleCoordinate] = "coordinate";
	roles[MapLocation::RoleName] = "name";
	roles[MapLocation::RolePixmap] = "pixmap";
	roles[MapLocation::RoleZ] = "z";
	roles[MapLocation::RoleIsSelected] = "isSelected";
	return roles;
}

int MapLocationModel::rowCount(const QModelIndex&) const
{
	return (int)m_mapLocations.size();
}

/* UNUSED?
void MapLocationModel::add(MapLocation *location)
{
	beginInsertRows(QModelIndex(), (int)m_mapLocations.size(), (int)m_mapLocations.size());
	m_mapLocations.append(location);
	endInsertRows();
}
*/

const std::vector<dive_site *> &MapLocationModel::selectedDs() const
{
	return m_selectedDs;
}

static bool hasVisibleDive(const dive_site &ds)
{
	return std::any_of(ds.dives.begin(), ds.dives.end(),
			   [] (const dive *d) { return !d->hidden_by_filter; });
}

static bool hasSelectedDive(const dive_site &ds)
{
	return std::any_of(ds.dives.begin(), ds.dives.end(),
			   [] (const dive *d) { return d->selected; });
}

void MapLocationModel::selectionChanged()
{
	if (m_mapLocations.empty())
		return;
	for(MapLocation &m: m_mapLocations)
		m.selected = range_contains(m_selectedDs, m.divesite);
	emit dataChanged(createIndex(0, 0), createIndex((int)m_mapLocations.size() - 1, 0));
}

void MapLocationModel::reload(QObject *map)
{
	beginResetModel();

	m_mapLocations.clear();
	m_selectedDs.clear();

	std::map<QString, size_t> locationNameMap;

#if defined(SUBSURFACE_MOBILE) || defined(SUBSURFACE_DOWNLOADER)
	bool diveSiteMode = false;
#else
	// In dive site mode (that is when either editing a dive site or on
	// the dive site tab), we want to show all dive sites, not only those
	// of the non-hidden dives. Moreover, the selected dive sites are those
	// that we filter for.
	bool diveSiteMode = DiveFilter::instance()->diveSiteMode();
	if (diveSiteMode)
		m_selectedDs = DiveFilter::instance()->filteredDiveSites();
#endif
	for (const auto &ds: divelog.sites) {
		QGeoCoordinate dsCoord;

		// Don't show dive sites of hidden dives, unless we're in dive site edit mode.
		if (!diveSiteMode && !hasVisibleDive(*ds))
			continue;
		if (!dive_site_has_gps_location(ds.get())) {
			// Dive sites that do not have a gps location are not shown in normal mode.
			// In dive-edit mode, selected sites are placed at the center of the map,
			// so that the user can drag them somewhere without having to enter coordinates.
			if (!diveSiteMode || !range_contains(m_selectedDs, ds.get()) || !map)
				continue;
			dsCoord = map->property("center").value<QGeoCoordinate>();
		} else {
			qreal latitude = ds->location.lat.udeg * 0.000001;
			qreal longitude = ds->location.lon.udeg * 0.000001;
			dsCoord = QGeoCoordinate(latitude, longitude);
		}
		if (!diveSiteMode && hasSelectedDive(*ds) && !range_contains(m_selectedDs, ds.get()))
			m_selectedDs.push_back(ds.get());
		QString name = siteMapDisplayName(ds->name);
		if (!diveSiteMode) {
			// don't add dive locations with the same name, unless they are
			// at least MIN_DISTANCE_BETWEEN_DIVE_SITES_M apart
			auto it = locationNameMap.find(name);
			if (it != locationNameMap.end()) {
				const MapLocation &existingLocation = m_mapLocations[it->second];
				QGeoCoordinate coord = existingLocation.coordinate;
				if (dsCoord.distanceTo(coord) < MIN_DISTANCE_BETWEEN_DIVE_SITES_M)
					continue;
			}
		}
		bool selected = range_contains(m_selectedDs, ds.get());
		m_mapLocations.emplace_back(ds.get(), dsCoord, name, selected);
		if (!diveSiteMode)
			locationNameMap[name] = m_mapLocations.size() - 1;
	}

	endResetModel();
}

void MapLocationModel::setSelected(struct dive_site *ds)
{
	m_selectedDs.clear();
	if (ds)
		m_selectedDs.push_back(ds);
}

void MapLocationModel::setSelected(const std::vector<dive_site *> &divesites)
{
	m_selectedDs = divesites;
}

MapLocation *MapLocationModel::getMapLocation(const struct dive_site *ds)
{
	for (MapLocation &location: m_mapLocations) {
		if (location.divesite == ds)
			return &location;
	}
	return nullptr;
}

void MapLocationModel::diveSiteChanged(struct dive_site *ds, int field)
{
	// Find dive site
	auto it = std::find_if(m_mapLocations.begin(), m_mapLocations.end(),
			       [ds](auto &entry) { return entry.divesite == ds; });
	if (it == m_mapLocations.end())
		return;

	switch (field) {
	case LocationInformationModel::LOCATION:
		if (has_location(&ds->location)) {
			const qreal latitude_r = ds->location.lat.udeg * 0.000001;
			const qreal longitude_r = ds->location.lon.udeg * 0.000001;
			QGeoCoordinate coord(latitude_r, longitude_r);
			it->coordinate = coord;
		}
		break;
	case LocationInformationModel::NAME:
		it->name = siteMapDisplayName(ds->name);
		break;
	default:
		break;
	}

	int row = static_cast<int>(it - m_mapLocations.begin());
	emit dataChanged(createIndex(row, 0), createIndex(row, 0));
}