/*
 * Copyright (c) 2012, 2016, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package javafx.scene.control.cell;

import javafx.beans.InvalidationListener;
import javafx.beans.Observable;
import javafx.beans.property.ObjectProperty;
import javafx.collections.ObservableList;
import javafx.scene.Node;
import javafx.scene.control.Cell;
import javafx.scene.control.ChoiceBox;
import javafx.scene.control.ComboBox;
import javafx.scene.control.ListView;
import javafx.scene.control.Skin;
import javafx.scene.control.TextField;
import javafx.scene.control.TreeItem;
import javafx.scene.control.skin.ComboBoxListViewSkin;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.HBox;
import javafx.util.StringConverter;

// Package protected - not intended for external use
class CellUtils {

    static int TREE_VIEW_HBOX_GRAPHIC_PADDING = 3;

    
                                                                        *
Private fields                                                          *
                                                                        *
/***************************************************************************
     *                                                                         *
     * Private fields                                                          *
     *                                                                         *
     **************************************************************************/

    private final static StringConverter<?> defaultStringConverter = new StringConverter<Object>() {
        @Override public String toString(Object t) {
            return t == null ? null : t.toString();
        }

        @Override public Object fromString(String string) {
            return (Object) string;
        }
    };

    private final static StringConverter<?> defaultTreeItemStringConverter =
        new StringConverter<TreeItem<?>>() {
            @Override public String toString(TreeItem<?> treeItem) {
                return (treeItem == null || treeItem.getValue() == null) ?
                        "" : treeItem.getValue().toString();
            }

            @Override public TreeItem<?> fromString(String string) {
                return new TreeItem<>(string);
            }
        };

    
                                                                        *
General convenience                                                     *
                                                                        *
/***************************************************************************
     *                                                                         *
     * General convenience                                                     *
     *                                                                         *
     **************************************************************************/

    /*
     * Simple method to provide a StringConverter implementation in various cell
     * implementations.
     */
    @SuppressWarnings("unchecked")
    static <T> StringConverter<T> defaultStringConverter() {
        return (StringConverter<T>) defaultStringConverter;
    }

    /*
     * Simple method to provide a TreeItem-specific StringConverter
     * implementation in various cell implementations.
     */
    @SuppressWarnings("unchecked")
    static <T> StringConverter<TreeItem<T>> defaultTreeItemStringConverter() {
        return (StringConverter<TreeItem<T>>) defaultTreeItemStringConverter;
    }

    private static <T> String getItemText(Cell<T> cell, StringConverter<T> converter) {
        return converter == null ?
            cell.getItem() == null ? "" : cell.getItem().toString() :
            converter.toString(cell.getItem());
    }


    static Node getGraphic(TreeItem<?> treeItem) {
        return treeItem == null ? null : treeItem.getGraphic();
    }



    
                                                                        *
ChoiceBox convenience                                                   *
                                                                        *
/***************************************************************************
     *                                                                         *
     * ChoiceBox convenience                                                   *
     *                                                                         *
     **************************************************************************/

    static <T> void updateItem(final Cell<T> cell,
                               final StringConverter<T> converter,
                               final ChoiceBox<T> choiceBox) {
        updateItem(cell, converter, null, null, choiceBox);
    }

    static <T> void updateItem(final Cell<T> cell,
                               final StringConverter<T> converter,
                               final HBox hbox,
                               final Node graphic,
                               final ChoiceBox<T> choiceBox) {
        if (cell.isEmpty()) {
            cell.setText(null);
            cell.setGraphic(null);
        } else {
            if (cell.isEditing()) {
                if (choiceBox != null) {
                    choiceBox.getSelectionModel().select(cell.getItem());
                }
                cell.setText(null);

                if (graphic != null) {
                    hbox.getChildren().setAll(graphic, choiceBox);
                    cell.setGraphic(hbox);
                } else {
                    cell.setGraphic(choiceBox);
                }
            } else {
                cell.setText(getItemText(cell, converter));
                cell.setGraphic(graphic);
            }
        }
    };

    static <T> ChoiceBox<T> createChoiceBox(
            final Cell<T> cell,
            final ObservableList<T> items,
            final ObjectProperty<StringConverter<T>> converter) {
        ChoiceBox<T> choiceBox = new ChoiceBox<T>(items);
        choiceBox.setMaxWidth(Double.MAX_VALUE);
        choiceBox.converterProperty().bind(converter);
        choiceBox.showingProperty().addListener(o -> {
            if (!choiceBox.isShowing()) {
                cell.commitEdit(choiceBox.getSelectionModel().getSelectedItem());
            }
        });
        return choiceBox;
    }



    
                                                                        *
TextField convenience                                                   *
                                                                        *
/***************************************************************************
     *                                                                         *
     * TextField convenience                                                   *
     *                                                                         *
     **************************************************************************/

    static <T> void updateItem(final Cell<T> cell,
                               final StringConverter<T> converter,
                               final TextField textField) {
        updateItem(cell, converter, null, null, textField);
    }

    static <T> void updateItem(final Cell<T> cell,
                               final StringConverter<T> converter,
                               final HBox hbox,
                               final Node graphic,
                               final TextField textField) {
        if (cell.isEmpty()) {
            cell.setText(null);
            cell.setGraphic(null);
        } else {
            if (cell.isEditing()) {
                if (textField != null) {
                    textField.setText(getItemText(cell, converter));
                }
                cell.setText(null);

                if (graphic != null) {
                    hbox.getChildren().setAll(graphic, textField);
                    cell.setGraphic(hbox);
                } else {
                    cell.setGraphic(textField);
                }
            } else {
                cell.setText(getItemText(cell, converter));
                cell.setGraphic(graphic);
            }
        }
    }

    static <T> void startEdit(final Cell<T> cell,
                              final StringConverter<T> converter,
                              final HBox hbox,
                              final Node graphic,
                              final TextField textField) {
        if (textField != null) {
            textField.setText(getItemText(cell, converter));
        }
        cell.setText(null);

        if (graphic != null) {
            hbox.getChildren().setAll(graphic, textField);
            cell.setGraphic(hbox);
        } else {
            cell.setGraphic(textField);
        }

        textField.selectAll();

        // requesting focus so that key input can immediately go into the
        // TextField (see RT-28132)
        textField.requestFocus();
    }

    static <T> void cancelEdit(Cell<T> cell, final StringConverter<T> converter, Node graphic) {
        cell.setText(getItemText(cell, converter));
        cell.setGraphic(graphic);
    }

    static <T> TextField createTextField(final Cell<T> cell, final StringConverter<T> converter) {
        final TextField textField = new TextField(getItemText(cell, converter));

        // Use onAction here rather than onKeyReleased (with check for Enter),
        // as otherwise we encounter RT-34685
        textField.setOnAction(event -> {
            if (converter == null) {
                throw new IllegalStateException(
                        "Attempting to convert text input into Object, but provided "
                                + "StringConverter is null. Be sure to set a StringConverter "
                                + "in your cell factory.");
            }
            cell.commitEdit(converter.fromString(textField.getText()));
            event.consume();
        });
        textField.setOnKeyReleased(t -> {
            if (t.getCode() == KeyCode.ESCAPE) {
                cell.cancelEdit();
                t.consume();
            }
        });
        return textField;
    }



    
                                                                        *
ComboBox convenience                                                   *
                                                                        *
/***************************************************************************
     *                                                                         *
     * ComboBox convenience                                                   *
     *                                                                         *
     **************************************************************************/

    static <T> void updateItem(Cell<T> cell, StringConverter<T> converter, ComboBox<T> comboBox) {
        updateItem(cell, converter, null, null, comboBox);
    }

    static <T> void updateItem(final Cell<T> cell,
                               final StringConverter<T> converter,
                               final HBox hbox,
                               final Node graphic,
                               final ComboBox<T> comboBox) {
        if (cell.isEmpty()) {
            cell.setText(null);
            cell.setGraphic(null);
        } else {
            if (cell.isEditing()) {
                if (comboBox != null) {
                    comboBox.getSelectionModel().select(cell.getItem());
                }
                cell.setText(null);

                if (graphic != null) {
                    hbox.getChildren().setAll(graphic, comboBox);
                    cell.setGraphic(hbox);
                } else {
                    cell.setGraphic(comboBox);
                }
            } else {
                cell.setText(getItemText(cell, converter));
                cell.setGraphic(graphic);
            }
        }
    };

    static <T> ComboBox<T> createComboBox(final Cell<T> cell,
                                          final ObservableList<T> items,
                                          final ObjectProperty<StringConverter<T>> converter) {
        ComboBox<T> comboBox = new ComboBox<T>(items);
        comboBox.converterProperty().bind(converter);
        comboBox.setMaxWidth(Double.MAX_VALUE);

        // setup listeners to properly commit any changes back into the data model.
        // First listener attempts to commit or cancel when the ENTER or ESC keys are released.
        // This is applicable in cases where the ComboBox is editable, and the user has
        // typed some input, and also when the ComboBox popup is showing.
        comboBox.addEventFilter(KeyEvent.KEY_RELEASED, e -> {
            if (e.getCode() == KeyCode.ENTER) {
                tryComboBoxCommit(comboBox, cell);
            } else if (e.getCode() == KeyCode.ESCAPE) {
                cell.cancelEdit();
            }
        });

        // Second listener attempts to commit when the user is in the editor of
        // the ComboBox, and moves focus away.
        comboBox.getEditor().focusedProperty().addListener(o -> {
            if (!comboBox.isFocused()) {
                tryComboBoxCommit(comboBox, cell);
            }
        });

        // Third listener makes an assumption about the skin being used, and attempts to add
        // a listener to the ListView within it, such that when the user mouse clicks on a
        // on an item, that is immediately committed and the cell exits the editing mode.
        boolean success = listenToComboBoxSkin(comboBox, cell);
        if (!success) {
            comboBox.skinProperty().addListener(new InvalidationListener() {
                @Override public void invalidated(Observable observable) {
                    boolean successInListener = listenToComboBoxSkin(comboBox, cell);
                    if (successInListener) {
                        comboBox.skinProperty().removeListener(this);
                    }
                }
            });
        }

        return comboBox;
    }

    private static <T> void tryComboBoxCommit(ComboBox<T> comboBox, Cell<T> cell) {
        StringConverter<T> sc = comboBox.getConverter();
        if (comboBox.isEditable() && sc != null) {
            T value = sc.fromString(comboBox.getEditor().getText());
            cell.commitEdit(value);
        } else {
            cell.commitEdit(comboBox.getValue());
        }
    }

    private static <T> boolean listenToComboBoxSkin(final ComboBox<T> comboBox, final Cell<T> cell) {
        Skin<?> skin = comboBox.getSkin();
        if (skin != null && skin instanceof ComboBoxListViewSkin) {
            ComboBoxListViewSkin cbSkin = (ComboBoxListViewSkin) skin;
            Node popupContent = cbSkin.getPopupContent();
            if (popupContent != null && popupContent instanceof ListView) {
                popupContent.addEventHandler(MouseEvent.MOUSE_RELEASED, e -> cell.commitEdit(comboBox.getValue()));
                return true;
            }
        }
        return false;
    }
}