/*

 * Copyright (C) 2011 Openismus GmbH

 *

 * This file is part of GWT-Glom.

 *

 * GWT-Glom is free software: you can redistribute it and/or modify it

 * under the terms of the GNU Lesser General Public License as published by the

 * Free Software Foundation, either version 3 of the License, or (at your

 * option) any later version.

 *

 * GWT-Glom is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License

 * for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with GWT-Glom.  If not, see <http://www.gnu.org/licenses/>.

 */

package org.glom.web.client.activity;

import java.util.ArrayList;

import org.glom.web.client.StringUtils;

import org.glom.web.client.ClientFactory;

import org.glom.web.client.OnlineGlomServiceAsync;

import org.glom.web.client.Utils;

import org.glom.web.client.event.LocaleChangeEvent;

import org.glom.web.client.event.LocaleChangeEventHandler;

import org.glom.web.client.event.QuickFindChangeEvent;

import org.glom.web.client.event.QuickFindChangeEventHandler;

import org.glom.web.client.event.TableChangeEvent;

import org.glom.web.client.event.TableChangeEventHandler;

import org.glom.web.client.place.DetailsPlace;

import org.glom.web.client.place.DocumentSelectionPlace;

import org.glom.web.client.place.ListPlace;

import org.glom.web.client.ui.DetailsView;

import org.glom.web.client.ui.View;

import org.glom.web.client.ui.cell.NavigationButtonCell;

import org.glom.web.client.ui.details.DetailsCell;

import org.glom.web.client.ui.details.Portal;

import org.glom.web.client.ui.details.RelatedListTable;

import org.glom.web.shared.DataItem;

import org.glom.web.shared.DetailsLayoutAndData;

import org.glom.web.shared.NavigationRecord;

import org.glom.web.shared.TypedDataItem;

import org.glom.web.shared.layout.LayoutGroup;

import org.glom.web.shared.layout.LayoutItemField;

import org.glom.web.shared.layout.LayoutItemPortal;

import com.google.gwt.activity.shared.AbstractActivity;

import com.google.gwt.cell.client.ValueUpdater;

import com.google.gwt.core.client.GWT;

import com.google.gwt.dom.client.Element;

import com.google.gwt.dom.client.NativeEvent;

import com.google.gwt.event.dom.client.ClickEvent;

import com.google.gwt.event.dom.client.ClickHandler;

import com.google.gwt.event.shared.EventBus;

import com.google.gwt.place.shared.Place;

import com.google.gwt.user.client.rpc.AsyncCallback;

import com.google.gwt.user.client.ui.AcceptsOneWidget;

/**

 *

 */

public class DetailsActivity extends AbstractActivity implements View.Presenter {

	/*

	 * Cell renderer for the related list open buttons. Normally this wouldn't be in an Activity class but since it's

	 * making a call to the server it makes sense for it to be here.

	 */

	private class RelatedListNavigationButtonCell extends NavigationButtonCell {

		private final String relationshipName;

		public RelatedListNavigationButtonCell(final String relationshipName) {

			this.relationshipName = relationshipName;

		}

		/*

		 * (non-Javadoc)

		 * 

		 * @see com.google.gwt.cell.client.ButtonCell#onEnterKeyDown(com.google.gwt.cell.client.Cell.Context,

		 * com.google.gwt.dom.client.Element, java.lang.String, com.google.gwt.dom.client.NativeEvent,

		 * com.google.gwt.cell.client.ValueUpdater)

		 */

		@Override

		protected void onEnterKeyDown(final Context context, final Element parent, final String value,

				final NativeEvent event, final ValueUpdater<String> valueUpdater) {

			final AsyncCallback<NavigationRecord> callback = new AsyncCallback<NavigationRecord>() {

				@Override

				public void onFailure(final Throwable caught) {

					// TODO: create a way to notify users of asynchronous callback failures

					GWT.log("AsyncCallback Failed: OnlineGlomService.getSuitableRecordToViewDetails()");

				}

				@Override

				public void onSuccess(final NavigationRecord result) {

					processNavigation(result.getTableName(), result.getPrimaryKeyValue());

				}

			};

			OnlineGlomServiceAsync.Util.getInstance().getSuitableRecordToViewDetails(documentID, tableName,

					relationshipName, (TypedDataItem) context.getKey(), callback);

		}

	}

	private String documentID = "";

	private String tableName = "";

	private TypedDataItem primaryKeyValue;

	private final ClientFactory clientFactory;

	private final DetailsView detailsView;

	ArrayList<DetailsCell> detailsCells;

	ArrayList<Portal> portals;

	public DetailsActivity(final DetailsPlace place, final ClientFactory clientFactory) {

		this.documentID = place.getDocumentID();

		this.tableName = place.getTableName();

		this.primaryKeyValue = place.getPrimaryKeyValue();

		this.clientFactory = clientFactory;

		detailsView = clientFactory.getDetailsView();

	}

	/*

	 * (non-Javadoc)

	 * 

	 * @see com.google.gwt.activity.shared.Activity#start(com.google.gwt.user.client.ui.AcceptsOneWidget,

	 * com.google.gwt.event.shared.EventBus)

	 */

	@Override

	public void start(final AcceptsOneWidget panel, final EventBus eventBus) {

		if (StringUtils.isEmpty(documentID))

			goTo(new DocumentSelectionPlace());

		// register this class as the presenter

		detailsView.setPresenter(this);

		// TODO here's where we should check for database authentication - see ListActivity.start() for how to do this

		// set the change handler for the table selection widget

		eventBus.addHandler(TableChangeEvent.TYPE, new TableChangeEventHandler() {

			@Override

			public void onTableChange(final TableChangeEvent event) {

				// note the empty primary key item

				goTo(new DetailsPlace(documentID, event.getNewTableName(), new TypedDataItem()));

			}

		});

		// get the layout and data for the DetailsView

		final AsyncCallback<DetailsLayoutAndData> callback = new AsyncCallback<DetailsLayoutAndData>() {

			@Override

			public void onFailure(final Throwable caught) {

				// TODO: create a way to notify users of asynchronous callback failures

				GWT.log("AsyncCallback Failed: OnlineGlomService.getDetailsLayoutAndData()");

			}

			@Override

			public void onSuccess(final DetailsLayoutAndData result) {

				if (result == null) {

					// The result is null only when the documentID was not found. There's nothing to display without the

					// documentID.

					goTo(new DocumentSelectionPlace());

				} else {

					// create the layout and set the data

					createLayout(result.getLayout());

					setData(result.getData());

				}

			}

		};

		final String localeID = Utils.getCurrentLocaleID();

		OnlineGlomServiceAsync.Util.getInstance().getDetailsLayoutAndData(documentID, tableName, primaryKeyValue,

				localeID, callback);

		// set the change handler for the quickfind text widget

		eventBus.addHandler(QuickFindChangeEvent.TYPE, new QuickFindChangeEventHandler() {

			@Override

			public void onQuickFindChange(final QuickFindChangeEvent event) {

				// We switch to the List view, to show search results.

				// TODO: Show the details view if there is only one result.

				goTo(new ListPlace(documentID, tableName, event.getNewQuickFindText()));

			}

		});

		// Set the change handler for the table selection widget

		eventBus.addHandler(LocaleChangeEvent.TYPE, new LocaleChangeEventHandler() {

			@Override

			public void onLocaleChange(final LocaleChangeEvent event) {

				// note the empty primary key item

				goTo(new DetailsPlace(documentID, tableName, primaryKeyValue));

			}

		});

		// indicate that the view is ready to be displayed

		panel.setWidget(detailsView.asWidget());

	}

	/*

	 * Create the layout.

	 */

	private void createLayout(final ArrayList<LayoutGroup> layout) {

		// add the groups

		for (final LayoutGroup layoutGroup : layout) {

			detailsView.addGroup(layoutGroup);

		}

		// save references to the DetailsCells and the Portals

		detailsCells = detailsView.getCells();

		portals = detailsView.getPortals();

		// Setup click handlers for the navigation buttons

		for (final DetailsCell detailsCell : detailsCells) {

			final LayoutItemField layoutItemField = detailsCell.getLayoutItemField();

			if (layoutItemField.getAddNavigation()) {

				detailsCell.setOpenButtonClickHandler(new ClickHandler() {

					@Override

					public void onClick(final ClickEvent event) {

						final TypedDataItem primaryKeyItem = Utils.getTypedDataItem(layoutItemField.getType(),

								detailsCell.getData());

						processNavigation(layoutItemField.getNavigationTableName(), primaryKeyItem);

					}

				});

			}

		}

	}

	/*

	 * Set the data.

	 */

	private void setData(final DataItem[] data) {

		if (data == null)

			return;

		// TODO create proper client side logging

		if (data.length != detailsCells.size())

			GWT.log("Warning: The number of data items doesn't match the number of data detailsCells.");

		for (int i = 0; i < Math.min(detailsCells.size(), data.length); i++) {

			final DetailsCell detailsCell = detailsCells.get(i);

			if (data[i] != null) {

				// set the DatailsItem

				detailsCell.setData(data[i]);

				// see if there are any related lists that need to be setup

				for (final Portal portal : portals) {

					final LayoutItemField layoutItemField = detailsCell.getLayoutItemField();

					final LayoutItemPortal layoutItemPortal = portal.getLayoutItem();

					if (layoutItemField.getName().equals(layoutItemPortal.getFromField())) {

						if (data[i] == null)

							continue;

						final TypedDataItem foreignKeyValue = Utils

								.getTypedDataItem(layoutItemField.getType(), data[i]);

						final RelatedListTable relatedListTable = new RelatedListTable(documentID, layoutItemPortal,

								foreignKeyValue, new RelatedListNavigationButtonCell(layoutItemPortal.getName()));

						if (!layoutItemPortal.getAddNavigation()

								|| layoutItemPortal.getNavigationType() == LayoutItemPortal.NavigationType.NAVIGATION_NONE) {

							relatedListTable.hideNavigationButtons();

						}

						portal.setContents(relatedListTable);

						setRowCountForRelatedListTable(relatedListTable, layoutItemPortal.getName(), foreignKeyValue);

					}

				}

			}

		}

	}

	private void refreshData() {

		// get the data for the DetailsView

		final AsyncCallback<DataItem[]> callback = new AsyncCallback<DataItem[]>() {

			@Override

			public void onFailure(final Throwable caught) {

				// TODO: create a way to notify users of asynchronous callback failures

				GWT.log("AsyncCallback Failed: OnlineGlomService.getDetailsData()");

			}

			@Override

			public void onSuccess(final DataItem[] result) {

				setData(result);

			}

		};

		OnlineGlomServiceAsync.Util.getInstance().getDetailsData(documentID, tableName, primaryKeyValue, callback);

	}

	// sets the row count for the related list table

	private void setRowCountForRelatedListTable(final RelatedListTable relatedListTable, final String relationshipName,

			final TypedDataItem foreignKeyValue) {

		final AsyncCallback<Integer> callback = new AsyncCallback<Integer>() {

			@Override

			public void onFailure(final Throwable caught) {

				// TODO: create a way to notify users of asynchronous callback failures

				GWT.log("AsyncCallback Failed: OnlineGlomService.getRelatedListRowCount()");

			}

			@Override

			public void onSuccess(final Integer result) {

				if (result.intValue() <= relatedListTable.getMinNumVisibleRows()) {

					// Set the table row count to the minimum row count if the data row count is less than or equal to

					// the minimum row count. This ensures that data with fewer rows than the minimum will not create

					// indexes in the underlying CellTable that will override the rendering of the empty rows.

					relatedListTable.setRowCount(relatedListTable.getMinNumVisibleRows());

				} else {

					// Set the table row count to the data row count if it's larger than the minimum number of rows

					// visible.

					relatedListTable.setRowCount(result.intValue());

				}

			}

		};

		OnlineGlomServiceAsync.Util.getInstance().getRelatedListRowCount(documentID, tableName, relationshipName,

				foreignKeyValue, callback);

	}

	/*

	 * Process a navigation by either doing: nothing if the navigation isn't valid, refreshing the data for the current

	 * table with a new primary key, or going to a new table with a new primary key.

	 */

	private void processNavigation(final String navigationTableName, final TypedDataItem navigationPrimaryKeyValue) {

		// Ensure the new table name is valid.

		String newTableName;

		if (!StringUtils.isEmpty(navigationTableName)) {

			newTableName = navigationTableName;

		} else {

			newTableName = tableName;

		}

		// Only process the navigation if there's a valid primary key value.

		if (navigationPrimaryKeyValue != null && !navigationPrimaryKeyValue.isEmpty()) {

			if (!newTableName.equals(tableName)) {

				// Go to a new DetailsPlace because the table name has changed.

				goTo(new DetailsPlace(documentID, newTableName, navigationPrimaryKeyValue));

			} else {

				// Refresh the details view with the new primary because the table name has not changed.

				primaryKeyValue = navigationPrimaryKeyValue;

				refreshData();

			}

		} else {

			// TODO notify the user that navigation isn't possible.

			// This is what Glom displays:

			// Frame_Glom::show_ok_dialog(_("No Corresponding Record Exists"),

			// _("No record with this value exists. Therefore navigation to the related record is not possible."),

			// *window, Gtk::MESSAGE_WARNING);

			// TODO: Make it more clear to the user exactly what record, what field, and what value, we are talking

			// about.

		}

	}

	/*

	 * (non-Javadoc)

	 * 

	 * @see com.google.gwt.activity.shared.Activity#onCancel()

	 */

	@Override

	public void onCancel() {

		detailsView.clear();

	}

	/*

	 * (non-Javadoc)

	 * 

	 * @see com.google.gwt.activity.shared.Activity#onStop()

	 */

	@Override

	public void onStop() {

		detailsView.clear();

	}

	/*

	 * (non-Javadoc)

	 * 

	 * @see org.glom.web.client.ui.View.Presenter#goTo(com.google.gwt.place.shared.Place)

	 */

	@Override

	public void goTo(final Place place) {

		clientFactory.getPlaceController().goTo(place);

	}

}