#include <BALL/PLUGIN/pluginManager.h>
#include <BALL/PLUGIN/BALLPlugin.h>

#include <BALL/VIEW/WIDGETS/scene.h>
#include <BALL/VIEW/KERNEL/mainControl.h>
#include <BALL/VIEW/KERNEL/iconLoader.h>
#include <BALL/VIEW/DIALOGS/preferences.h>
#include <BALL/VIEW/DIALOGS/displayProperties.h>
#include <BALL/VIEW/DIALOGS/pluginDialog.h>
#include <BALL/VIEW/PLUGIN/VIEWPlugin.h>

#include <BALL/VIEW/UIC/ui_pluginDialog.h>

Q_DECLARE_METATYPE(BALL::VIEW::VIEWPlugin*)

#include <QtCore/QCoreApplication>
#include <QtCore/QLibraryInfo>
#include <QtWidgets/QFileDialog>

namespace BALL
{
	namespace VIEW
	{
		/*
		 * Implementation of PluginModel
		 */
		PluginModel::PluginModel(QObject* parent)
			: QAbstractListModel(parent),
			  num_rows_(0)
		{
		}

		int PluginModel::rowCount(const QModelIndex& /* parent */) const
		{
			return num_rows_;
		}

		void PluginModel::pluginsLoaded()
		{
			int nrow = num_rows_;
			num_rows_ = PluginManager::instance().getPluginCount();
			beginInsertRows(QModelIndex(), nrow, num_rows_);
			endInsertRows();
		}

		QVariant PluginModel::data(const QModelIndex& i, int role) const
		{
			if(!i.isValid())
			{
				return QVariant();
			}

			PluginManager& man = PluginManager::instance();

			if(i.row() >= num_rows_)
			{
				return QVariant();
			}

			switch(role)
			{
				case Qt::UserRole:
					return qVariantFromValue(man.getPluginInstance(i.row()));

				case Qt::DisplayRole:
				{
					BALLPlugin* ptr = qobject_cast<BALLPlugin *>(man.getPluginInstance(i.row()));

					// we *know* that this is a BALLPlugin (the loader takes care of that), so we don't need
					// to test if the cast succeeded
					return ptr->getName() + " (" + (ptr->isActive() ? tr("active") : tr("inactive")) + ")";
				}

				case Qt::DecorationRole:
				{
					VIEWPlugin* ptr = qobject_cast<VIEWPlugin *>(man.getPluginInstance(i.row()));
					return ptr ? *(ptr->getIcon()) : QVariant();
				}

				case Qt::ToolTipRole:
				{
					VIEWPlugin *ptr = qobject_cast<VIEWPlugin *>(man.getPluginInstance(i.row()));
					return ptr ? ptr->getDescription() : QVariant();
				}

				default:
					return QVariant();
			}
		}

		/*
		 * Implementation of PluginDirectoryModel
		 */

		PluginDirectoryModel::PluginDirectoryModel(QObject* parent)
			: QAbstractListModel(parent)
		{
		}

		int PluginDirectoryModel::rowCount(const QModelIndex& /* parent */) const
		{
			PluginManager& man = PluginManager::instance();
			return man.getPluginDirectories().size();
		}

		QVariant PluginDirectoryModel::data(const QModelIndex& i, int role) const
		{
			if(!i.isValid()) {
				return QVariant();
			}

			PluginManager& man = PluginManager::instance();

			if((size_t)i.row() >= man.getPluginDirectories().size())
			{
				return QVariant();
			}

			switch(role)
			{
				case Qt::DisplayRole:
				{
					return man.getPluginDirectories()[i.row()];
				}

				default:
					return QVariant();
			}
		}

		void PluginDirectoryModel::addDirectory(const QString& dir)
		{
			PluginManager& man = PluginManager::instance();

			if(man.addPluginDirectory(dir)) {
				int idx = man.getPluginDirectories().size() - 1;

				beginInsertRows(QModelIndex(), idx, idx);
				endInsertRows();
			}
		}

		void PluginDirectoryModel::removeDirectory(const QModelIndex& idx)
		{
			PluginManager& man = PluginManager::instance();

			if(man.removePluginDirectory(idx.data(Qt::DisplayRole).toString())) {
				beginRemoveRows(QModelIndex(), idx.row(), idx.row());
				endRemoveRows();
			}
		}

		/*
		 * Implementation of PluginDialog
		 */
		PluginDialog::PluginDialog(Preferences* preferences, QWidget* parent, const char* name)
			: QWidget(parent),
			  ModularWidget(name),
			  preferences_(preferences)
		{
			ui_ = new Ui::PluginDialogData;
			ui_->setupUi(this);

			// define the dialogs section name in the INIFile
			setINIFileSectionName("PLUGINS");
			stack_pages_.push_back(std::make_pair(this, tr("Plugins").toStdString()));

			preferences_->insertEntry(this);

			setObjectName(name);

			IconLoader& icon_loader = IconLoader::instance();

			ui_->plugin_dir_button_add->setIcon(icon_loader.getIcon("actions/list-add"));
			ui_->plugin_dir_button_remove->setIcon(icon_loader.getIcon("actions/edit-delete"));

			// register all visible childs
			registerWidgets_();

			ui_->plugin_view->setModel(&plugin_model_);
			ui_->plugin_directories_view->setModel(&plugin_dir_model_);

			plugin_model_.pluginsLoaded();

			setObjectName(name);
			ModularWidget::registerWidget(this);

			connect(ui_->plugin_dir_button_add, SIGNAL(clicked()), this, SLOT(addPluginDirectory()));
			connect(ui_->plugin_dir_button_remove, SIGNAL(clicked()), this, SLOT(removePluginDirectory()));
			connect(ui_->plugin_directories_view->selectionModel(), SIGNAL(currentChanged(const QModelIndex&, const QModelIndex&)), this, SLOT(directorySelectionChanged(const QModelIndex&, const QModelIndex&)));
			connect(ui_->plugin_view->selectionModel(), SIGNAL(currentChanged(const QModelIndex&, const QModelIndex&)), this, SLOT(pluginChanged(QModelIndex, const QModelIndex&)));
		}

		PluginDialog::~PluginDialog()
		{
			PluginManager::instance().unregisterHandler(this);
			delete ui_;
		}

		void PluginDialog::initializeWidget(MainControl&)
		{
			PreferencesEntry::restoreValues();
		}

		void PluginDialog::finalizeWidget(MainControl& mc)
		{
			ModularWidget::finalizeWidget(mc);
			PluginManager::instance().unloadAllPlugins();
		}

		void PluginDialog::writePreferenceEntries(INIFile& inifile)
		{
			PreferencesEntry::writePreferenceEntries(inifile);

			for (std::list<PreferencesEntry*>::iterator child_it = child_entries_.begin(); child_it != child_entries_.end(); ++child_it)
			{
				(*child_it)->writePreferenceEntries(inifile);
			}

			PluginManager& man = PluginManager::instance();

			if(!inifile.hasSection(getINIFileSectionName())) {
				inifile.appendSection(getINIFileSectionName());
			}

			String value;
			man.getPluginDirectories(value);

			inifile.insertValue(getINIFileSectionName(), "PluginDirectories", value);
			inifile.insertValue(getINIFileSectionName(), "ActivePlugins", man.getAutoActivatePlugins().toStdString());
		}

		void PluginDialog::readPreferenceEntries(const INIFile& inifile)
		{
			PreferencesEntry::readPreferenceEntries(inifile);

			plugin_model_.pluginsLoaded();

			for (std::list<PreferencesEntry*>::iterator child_it = child_entries_.begin(); 
					 child_it != child_entries_.end(); 
					 ++child_it)
			{
				(*child_it)->readPreferenceEntries(inifile);
			}

			PluginManager& man = PluginManager::instance();

			if (inifile.hasEntry(getINIFileSectionName(), "ActivePlugins"))
			{
				String active_plugins = inifile.getValue(getINIFileSectionName(), "ActivePlugins");
				man.setAutoActivatePlugins(active_plugins.c_str());
			}

			if (inifile.hasEntry(getINIFileSectionName(), "PluginDirectories"))
			{
				String plugin_directories = inifile.getValue(getINIFileSectionName(), "PluginDirectories");
				man.setPluginDirectories(plugin_directories);
			}
			else
			{
				setDefaultPluginDirectory();
			}
		}

		void PluginDialog::restoreDefaultValues(bool /* all */)
		{
			for (auto i = plugin_dir_model_.rowCount() - 1; i >= 0 ; --i)
			{
				plugin_dir_model_.removeDirectory(plugin_dir_model_.index(i));
			}
			setDefaultPluginDirectory();
		}

		void PluginDialog::pluginChanged(QModelIndex current, const QModelIndex& /* previous */)
		{
			//Cleanup the old config dialog
			active_index_ = current;
			QObject* active_object = qvariant_cast<QObject*>(plugin_model_.data(current, Qt::UserRole));

			BALLPlugin* active_plugin = qobject_cast<BALLPlugin*>(active_object);
			if (!active_plugin)
			{
				return;
			}

			ui_->plugin_toggle_button->setEnabled(true);
			if (active_plugin->isActive())
			{
				ui_->plugin_toggle_button->setText(tr("Deactivate"));
			}
			else
			{
				ui_->plugin_toggle_button->setText(tr("Activate"));
			}
		}

		void PluginDialog::addPluginDirectory()
		{
			QString dir = QFileDialog::getExistingDirectory(this, tr("Select a plugin directory"));
			if(!dir.isNull())
			{
				plugin_dir_model_.addDirectory(dir);
				plugin_model_.pluginsLoaded();
			}
		}

		void PluginDialog::removePluginDirectory()
		{
			// TODO: disable remove button if no item selected
			if (!ui_->plugin_directories_view->currentIndex().isValid())
			{
				return;
			}

			plugin_dir_model_.removeDirectory(ui_->plugin_directories_view->currentIndex());
			plugin_model_.pluginsLoaded();
		}

		void PluginDialog::directorySelectionChanged(const QModelIndex& current, const QModelIndex& /* previous */)
		{
			ui_->plugin_dir_button_remove->setEnabled(current.isValid());
		}

		void PluginDialog::togglePluginState()
		{
			if (!active_index_.isValid())
			{
				return;
			}

			QObject* active_object = qvariant_cast<QObject*>(plugin_model_.data(active_index_, Qt::UserRole));
			BALLPlugin* active_plugin = qobject_cast<BALLPlugin*>(active_object);
			if (active_plugin->isActive())
			{
				PluginManager::instance().doNotAutoActivatePlugin(active_plugin->getName());
				PluginManager::instance().stopPlugin(active_plugin);
				ui_->plugin_toggle_button->setText(tr("Activate"));
			}
			else
			{
				PluginManager::instance().autoActivatePlugin(active_plugin->getName());
				PluginManager::instance().startPlugin(active_plugin);
				ui_->plugin_toggle_button->setText(tr("Deactivate"));
			}

			ui_->plugin_view->update(active_index_);
		}

		void PluginDialog::registerChildEntry(PreferencesEntry* child)
		{
			if(!child) return;

			preferences_->insertChildEntry("PLUGINS", child);
			child_entries_.push_back(child);
		}

		void PluginDialog::unregisterChildEntry(PreferencesEntry* child)
		{
			if(!child) return;

			std::list<PreferencesEntry*>::iterator child_it = std::find(child_entries_.begin(), child_entries_.end(), child);
			child_entries_.erase(child_it);
			preferences_->removeEntry(child);
		}

		bool PluginDialog::canHandle(BALLPlugin* plugin) const
		{
			return dynamic_cast<VIEWPlugin*>(plugin) != 0;
		}

		bool PluginDialog::specificSetup_(BALLPlugin* plugin)
		{
			VIEWPlugin* view_plugin = dynamic_cast<VIEWPlugin*>(plugin);

			if(view_plugin->getConfigDialog() != 0 && preferences_ != 0)
			{
				registerChildEntry(view_plugin->getConfigDialog());
			}

			return true;
		}

		bool PluginDialog::specificShutdown_(BALLPlugin* plugin)
		{
			VIEWPlugin* view_plugin = dynamic_cast<VIEWPlugin*>(plugin);

			if(view_plugin->getConfigDialog() != 0 && preferences_ != 0)
			{
				unregisterChildEntry(view_plugin->getConfigDialog());
				view_plugin->getConfigDialog()->setParent(0);
			}

			return true;
		}

		void PluginDialog::setDefaultPluginDirectory()
		{
#ifdef BALL_OS_DARWIN

			// On macOS, we can locate potential default plugin directories relative
			// to the directory (absolute path) containing the BALLView binary.
			// The latter has the suffix BALLView.app/Contents/MacOS

			QDir app_dir = QDir(QCoreApplication::applicationDirPath());

			// Option 1: BALLView bundle installation
			// Plugins will reside in BALLView.app/Contents/plugins
			if(app_dir.cd("../plugins"))
			{
				plugin_dir_model_.addDirectory(app_dir.path());
			}
			else
			{
				// Option 2: BALLView build from source
				// Plugins will reside in <build_dir>/lib
				if (app_dir.cd("../../../../lib"))
				{
					plugin_dir_model_.addDirectory(app_dir.path());
				}
			}

#elif defined BALL_OS_LINUX

			// On Linux, we can locate the default plugin directory relative
			// to the directory (absolute path) containing the BALLView binary.

			QDir app_dir = QDir(QCoreApplication::applicationDirPath());

			// For installed BALLView binaries and source builds the folder hierarchy is identical.
			// BALLView will reside in <install_or_build_dir>/bin
			// Plugins will reside in  <install_or_build_dir>/lib
			if(app_dir.cd("../lib"))
			{
				plugin_dir_model_.addDirectory(app_dir.path());
			}

#elif defined BALL_OS_WINDOWS

			// On Windows, BALLView plugins reside in the same folder as the BALLView executable.
			// Thus, we simply can use this path as the default plugin directory.

			plugin_dir_model_.addDirectory(QCoreApplication::applicationDirPath());

#endif
			plugin_model_.pluginsLoaded();
		}
	}
}