/*
 * Copyright 2013 Digital Rapids Corporation.
 */
package vboxpopupwidth;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javafx.application.Application;
import javafx.collections.ObservableList;
import javafx.event.Event;
import javafx.event.EventHandler;
import javafx.geometry.Bounds;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.control.IndexRange;
import javafx.scene.control.Label;
import javafx.scene.control.ListView;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.input.MouseButton;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.VBox;
import javafx.stage.Popup;
import javafx.stage.Stage;
import javafx.stage.Window;

/**
 *
 * @author scott.palmer
 */
public class VBoxPopupWidth extends Application {
	private ListView<String> choiceList;
	private List<String> allAvailableChoices;
	private ObservableList<String> choices = javafx.collections.FXCollections.observableArrayList();
	private volatile Popup popup;
	
	private Label filterLabel;
	private String filterText = "";
	private TextField tf;
	
	@Override
	public void start(Stage primaryStage) {
		allAvailableChoices = Arrays.asList("one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten");
		tf = new TextField();
		tf.setPrefWidth(400);
		tf.setPromptText("Type $ to insert from a list");
		tf.addEventFilter(KeyEvent.KEY_PRESSED, keyPressed);
		tf.addEventFilter(KeyEvent.KEY_TYPED, keyTyped);
		
		filterLabel = new Label(filterText);
		filterLabel.setStyle("-fx-text-fill: white; -fx-background-color: grey; ");
		filterLabel.setMaxWidth(Double.MAX_VALUE);
		filterLabel.visibleProperty().bind(filterLabel.textProperty().isNotEqualTo(""));
		filterLabel.managedProperty().bind(filterLabel.visibleProperty());
		
		BorderPane root = new BorderPane();
		root.setCenter(new Label(
				  "Type in the field below.\n"
				+ "Typing a $ will bring up a popup.\n"
				+ "continuing to type will filter the\n"
				+ "available options in the list.\n"
				+ "Soemtimes the VBox width shrinks to\n"
				+ "the size of the label showing the\n"
				+ "current filter instead of allowing\n"
				+ "for the size of the list.\n\n"
				+ "Try typing '$', 't' then backspace.\n\n"
				+ "It all works fine in JavaFX 2.2"));
		root.setBottom(tf);
		Scene scene = new Scene(root, 300, 250);
		primaryStage.setTitle("Popup Layout Width Problem");
		primaryStage.setScene(scene);
		primaryStage.show();
	}
	
	private void doPickFromList() {
		filterLabel.setText(filterText);
		applyFilterToAvailableChoices();
		Popup choicePopup = new Popup();
		choiceList = new ListView<>(choices);
		VBox vbox = new VBox();
		vbox.getChildren().addAll(filterLabel, choiceList);
		choicePopup.getContent().add(vbox);
		choicePopup.setAutoHide(true);
		choicePopup.setHideOnEscape(false);
		choicePopup.setOnAutoHide(new EventHandler<Event>() {
			@Override
			public void handle(Event t) {
				popup = null;
			}
		});

		choiceList.addEventFilter(MouseEvent.MOUSE_CLICKED, new EventHandler<MouseEvent>() {
			@Override
			public void handle(MouseEvent t) {
				// if primary button double-click with no modifiers
				if (t.getClickCount() == 2 && t.isStillSincePress() && t.getButton() == MouseButton.PRIMARY
						&& !t.isAltDown() && !t.isControlDown() && !t.isShiftDown() && !t.isMetaDown()
						&& choiceList.getSelectionModel().getSelectedItem() != null) {
					// These extra checks are so we don't respond to a double click
					// on the scrollbar or inc/dec arrows.
					// TODO: something less fragile (need a heavier solution like custom ListCell)
					if (t.getTarget() instanceof Node) {
						Node n = (Node) t.getTarget();
						ObservableList<String> styles = n.getStyleClass();
						if (styles.contains("list-cell") || styles.contains("text")) {
							completeChoice();
							t.consume();
						}
					}
				}
			}
		});
		double screenX = 0;
		double screenY = 0;
		Scene scene = tf.getScene();
		Window w = scene.getWindow();
		if (w != null) {
			screenX = w.getX();
			screenY = w.getY();
		}
		screenX += scene.getX();
		screenY += scene.getY();
		Bounds bounds = tf.localToScene(tf.getBoundsInLocal());
		screenX += bounds.getMinX();
		screenY += bounds.getMinY() + bounds.getHeight();
		choicePopup.show(tf, screenX, screenY);
		popup = choicePopup;
	}

	private EventHandler<? super KeyEvent> keyPressed = new EventHandler<KeyEvent>() {
		@Override
		public void handle(KeyEvent t) {
			if (popup != null) {
				dealWithChoiceSelection(t);
				return;
			}
			// This one doesn't get called (with my keyboard that has $ on shift+4)
			if (t.getCode() == KeyCode.DOLLAR) {
				t.consume();
			} else if ("$".equals(t.getText())) {
				// must use getText for KEY_PRESSED events. (getCharacter is always CHAR_UNDEFINED)
				//System.err.println("Consuming the $ pressed event");
				t.consume();
			}
		}
	};
	private EventHandler<? super KeyEvent> keyTyped = new EventHandler<KeyEvent>() {
		@Override
		public void handle(KeyEvent t) {
			if (popup != null) {
				if (t.getCharacter().length() > 0) {
					char c = t.getCharacter().charAt(0);
					if (c == 27) {
						// Escape
						cancelChoiceInsertion();
					} else {
						if (c == 32 || c == 13 || c == 10) { // line feed?? It happens in JFXPanel in a JOptionPane!
							completeChoice();
						} else if (c == 8) {
							// backspace
							filterText = filterText.substring(0, Math.max(0, filterText.length() - 1));
							filterLabel.setText(filterText);
							applyFilterToAvailableChoices();
						} else if (Character.isLetterOrDigit(c) || c == '_') {
							String oldFilterText = filterText;
							filterText += c;
							boolean filterOk = applyFilterToAvailableChoices();
							if (!filterOk) {
								// display beep?
								filterText = oldFilterText;
							}
							filterLabel.setText(filterText);
						}
					}
				}

				t.consume();
				return;
			}
			// Must used getCharacter for KEY_TYPED events
			// (getText() is always empty, getCode() is always UNDEFINED)
			if ("$".equals(t.getCharacter())) {
				// insert a variable at caret position
				doPickFromList();
				t.consume();
			}
		}
	};
	
	
	private boolean applyFilterToAvailableChoices() {
		List<String> choicesThatMatch = new ArrayList<>();
		String filter = filterText.toLowerCase();
		for (String x : allAvailableChoices) {
			if (x.toLowerCase().startsWith(filter)) {
				choicesThatMatch.add(x);
			}
		}
		if (!choicesThatMatch.isEmpty()) {
			choices.setAll(choicesThatMatch);
			return true;
		}
		return false;
	}

	private void dealWithChoiceSelection(KeyEvent t) {
		if (t.getCode() == KeyCode.ESCAPE) {
			cancelChoiceInsertion();
		}
		if (t.getCode() == KeyCode.ENTER) {
			completeChoice();
		}
		t.consume();
	}
	
	private void cancelChoiceInsertion() {
		if (popup != null) {
			popup.hide();
		}
		popup = null;
		filterText = "";
	}
	
	private void completeChoice() {
		popup.hide();
		String var = choiceList.getSelectionModel().getSelectedItem();
		if (var == null && choices.size() == 1) {
			var = choices.get(0);
		}
		popup = null;
		if (var != null) {
			insertChoice(var);
		}
		filterText = "";
	}
	
	// called when a $ is typed
	private void insertChoice(String pick) {
		IndexRange selection = tf.getSelection();
		String text = tf.getText();
		if (text == null) {
			text = "";
		}

		// if there is a selection - replace it
		int selStart = selection.getStart();
		int selEnd = selection.getEnd();
		// Selection start & end follow the caret postion when there is no
		// selection.  We rely on this below.

		// pos will become selStart + length of inserted stuff
		String preText = text.substring(0, selStart);
		String postText = text.substring(selEnd, text.length());
		String insertedText = pick;
		String newText = preText + insertedText + postText;
		int pos = preText.length() + insertedText.length();

		tf.setText(newText);
		tf.positionCaret(pos); // This clears the selection as well
	}
	
	public static void main(String[] args) {
		launch(args);
	}
}