package application.customviews;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import application.UICoordinator;
import application.enums.EntryType;
import application.helpers.wrappers.Element;
import application.helpers.wrappers.SubElement;
import application.res.Backgrounds;
import application.res.Text;
import javafx.beans.binding.Bindings;
import javafx.beans.property.BooleanProperty;
import javafx.beans.property.SimpleBooleanProperty;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.event.EventHandler;
import javafx.scene.Node;
import javafx.scene.control.Label;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.AnchorPane;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.VBox;

/**
 * This class represents one element in the select view where the user can
 * select the data he / she wishes to contribute. The elements can contain
 * {@link SubEntryView}s with sub elements. Every EntryView can contain an info
 * view and may be opened for the sub elements (if they exist).
 * 
 * @author Bianca
 *
 */
public class EntryView extends VBox implements ChangeListener<Boolean>
{
	/**
	 * The {@link Element} represented by this {@link EntryView}.
	 */
	private Element elem;
	/**
	 * The header of the element. Is always visible.
	 */
	private AnchorPane header;
	/**
	 * Contains the detailed information for the element as defined in its
	 * {@link EntryType}.
	 */
	private BorderPane details;
	/**
	 * Contains the sub elements if they exist. If there are no subElements, the
	 * view will never be visible and there won't be a button to show it.
	 */
	private BorderPane subItem;
	/**
	 * Indicates whether the information part is currently shown.
	 */
	private boolean infoOpen = false;
	/**
	 * Indicates whether the sub elements are currently shown.
	 */
	private boolean subOpen = false;
	/**
	 * Indicates whether the whole element with all its sub elements is selected.
	 */
	private BooleanProperty selected;
	/**
	 * Represents the button to open the information view of the element.
	 */
	private BorderPane help;
	/**
	 * Represents the button to show the sub elements.
	 */
	private BorderPane open;
	/**
	 * Number of all sub elements.
	 */
	private int subElemCount = 0;
	/**
	 * Number of all selected sub elements.
	 */
	private int selectedSubElemCount = 0;

	/**
	 * Sets up an {@link EntryView} without sub elements.
	 * 
	 * @param elem The data of this entry.
	 */
	public EntryView(Element elem)
	{
		super();
		this.elem = elem;
		selected = new SimpleBooleanProperty(false);
		header = new AnchorPane();
		details = new BorderPane();
		details.setId("Details");
		subItem = new BorderPane();
		subItem.setId("SubItem");
		details.setCenter(new Label(elem.getType().getDesc()));
		header.minWidthProperty().bind(Bindings.createDoubleBinding(() -> this.getWidth(), this.widthProperty()));
		header.maxWidthProperty().bind(Bindings.createDoubleBinding(() -> this.getWidth(), this.widthProperty()));

		// right side (help button for showing further information)
		help = new BorderPane();
		help.setId("help");
		ImageView helpImage = new ImageView(new Image(UICoordinator.class.getResourceAsStream("help.png")));
		help.setCenter(helpImage);
		AnchorPane.setRightAnchor(help, 0.0);
		AnchorPane.setTopAnchor(help, 0.0);
		AnchorPane.setBottomAnchor(help, 0.0);

		help.setOnMouseClicked(new EventHandler<MouseEvent>()
		{
			@Override
			public void handle(MouseEvent arg0)
			{
				// always close sub elements first
				if (subOpen)
				{
					closeSub();
				}

				if (infoOpen)
				{
					closeInfo();
				}
				else
				{
					getChildren().add(1, details);
					infoOpen = true;
					help.setBackground(Backgrounds.greyBackground);
				}
			}

		});

		// middle (name and value etc)
		Label text = new Label(String.format(Text.F_ME_SAVE, elem.getType().getValue(), elem.getValue()));
		AnchorPane.setLeftAnchor(text, 50.0);
		AnchorPane.setTopAnchor(text, 0.0);
		AnchorPane.setBottomAnchor(text, 0.0);
		AnchorPane.setRightAnchor(text, 50.0);
		header.getChildren().add(text);
		text.minWidthProperty().bind(
				Bindings.createDoubleBinding(() -> header.getWidth() - help.getWidth() * 2, header.widthProperty()));
		text.setOnMouseClicked(new EventHandler<MouseEvent>()
		{
			@Override
			public void handle(MouseEvent event)
			{
				setSelected(!getSelected(), true);
			}
		});

		header.getChildren().add(help);
		getChildren().add(header);

	}

	/**
	 * Sets up an {@link EntryView} with sub elements.
	 * 
	 * @param elem       The data of this entry.
	 * @param subEntries The sub elements which belong to this element
	 */
	public EntryView(Element elem, HashMap<String, Integer> subEntries)
	{
		this(elem);
		VBox subContainer = new VBox();
		for (String entry : subEntries.keySet())
		{
			subElemCount++;
			SubEntryView sub = new SubEntryView(new SubElement(entry, subEntries.get(entry)));
			sub.addCheckListener(this);
			subContainer.getChildren().add(sub);
		}
		subItem.setCenter(subContainer);

		// left side
		open = new BorderPane();
		ImageView openImage = new ImageView(new Image(UICoordinator.class.getResourceAsStream("dreieck2.png")));
		open.setId("open");
		AnchorPane.setLeftAnchor(open, 0.0);
		AnchorPane.setTopAnchor(open, 0.0);
		AnchorPane.setBottomAnchor(open, 0.0);
		open.setCenter(openImage);
		openImage.setRotate(180);

		open.setOnMouseClicked(new EventHandler<MouseEvent>()
		{

			@Override
			public void handle(MouseEvent arg0)
			{
				// always close info first
				if (infoOpen)
				{
					closeInfo();
				}
				if (subOpen)
				{
					closeSub();
				}
				else
				{
					openSub();
				}
			}
		});

		header.getChildren().add(open);
	}

	/**
	 * Returns the value / count of this entry.
	 * 
	 * @return The described value.
	 */
	public String getValue()
	{
		return elem.getValue();
	}

	/**
	 * Closes the detailed information view if it is open
	 */
	private void closeInfo()
	{
		getChildren().remove(details);
		infoOpen = false;
		help.setBackground(Backgrounds.darkGreyBackground);
	}

	/**
	 * Shows the sub elements if they are not open yet.
	 */
	private void openSub()
	{
		getChildren().add(subItem);
		subOpen = true;
		open.setBackground(Backgrounds.greyBackground);
	}

	/**
	 * Closes the sub elements view if it is not closed yet.
	 */
	private void closeSub()
	{
		getChildren().remove(subItem);
		subOpen = false;
		open.setBackground(Backgrounds.darkGreyBackground);

	}

	/**
	 * Sets the value of the selection. If wanted it can also adjust the states of
	 * the {@link SubEntryView}s
	 * 
	 * @param value New value of the selection.
	 * @param all   If true then the {@link SubEntryView}s will also be adjusted.
	 *              Otherwise they won't be changed.
	 */
	public void setSelected(boolean value, boolean all)
	{
		this.selected.set(value);
		// adjust color of the entry
		if (!value)
		{
			header.setBackground(null);
		}
		else
		{
			header.setBackground(Backgrounds.greenBackground);
		}
		// adjust the sub elements
		if (all && subItem.getCenter() != null)
		{
			// there are subitems
			for (Node child : ((VBox) subItem.getCenter()).getChildren())
			{
				SubEntryView sub = (SubEntryView) child;
				sub.setSelected(value);
			}
		}
	}

	/**
	 * Gets the selection.
	 * 
	 * @return {@code True} if the entry or any sub entry is selected. {@code False}
	 *         otherwise.
	 */
	public boolean getSelected()
	{
		return selectedSubElemCount > 0 || selected.getValue();
	}

	/**
	 * Allows for a listener to be added to the selection value.
	 * 
	 * @param listen Listener to be added.
	 */
	public void addCheckListener(ChangeListener<Boolean> listen)
	{
		selected.addListener(listen);
	}

	/**
	 * Returns the {@link EntryType} of this {@link EntryView}.
	 * 
	 * @return The described value.
	 */
	public EntryType getEntryType()
	{
		return this.elem.getType();
	}

	@Override
	public void changed(ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue)
	{
		// Here the sub elements are watched and the selected ones counted
		if (newValue)
		{
			selectedSubElemCount++;
		}
		else
		{
			selectedSubElemCount--;
		}
		// if any sub element was selected then of course the whole
		// element also needs to be selected.
		if (selectedSubElemCount > 0)
		{
			this.selected.set(true);
		}
		else
		{
			this.selected.set(false);
		}

		// this adjusts the color of the element but not the selection of the sub
		// elements
		if (selectedSubElemCount == subElemCount)
		{
			setSelected(true, false);
		}
		else if (selectedSubElemCount > 0)
		{
			header.setBackground(Backgrounds.lightGreenBackground);
		}
		else
		{
			setSelected(false, false);
		}
	}

	/**
	 * Returns a list of readable names of all sub elements or an empty list if
	 * their are no sub elements.
	 * 
	 * @return The described value.
	 */
	public List<String> getSelectedSubElementNames()
	{
		List<String> res = new ArrayList<>();
		if (subItem.getCenter() != null)
		{
			// there are subitems
			for (Node child : ((VBox) subItem.getCenter()).getChildren())
			{
				SubEntryView sub = (SubEntryView) child;
				if (sub.isSelected())
				{
					res.add(sub.getName());
				}
			}
		}

		return res;
	}

	/**
	 * Returns all {@link SubEntryView}s of this entry in a list or an empty lift if
	 * there are now sub elements.
	 * 
	 * @return The described value.
	 */
	public List<SubEntryView> getSelectedSubElements()
	{
		List<SubEntryView> res = new ArrayList<>();
		if (subItem.getCenter() != null)
		{
			// there are sub elements
			for (Node child : ((VBox) subItem.getCenter()).getChildren())
			{
				SubEntryView sub = (SubEntryView) child;
				if (sub.isSelected())
				{
					res.add(sub);
				}
			}
		}

		return res;
	}

	public void selectSubelement(String elementName)
	{
		if (subItem.getCenter() != null)
		{
			// there are subitems
			for (Node child : ((VBox) subItem.getCenter()).getChildren())
			{
				SubEntryView sub = (SubEntryView) child;
				if (sub.getName().contains(elementName))
				{
					sub.setSelected(true);
				}
			}
		}

	}

}