/*
 * Copyright (c) 2011, 2015, 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 com.sun.javafx.scene.control.behavior;

import javafx.beans.property.ReadOnlyBooleanProperty;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.collections.ListChangeListener;
import javafx.collections.ObservableList;
import javafx.scene.control.Accordion;
import javafx.scene.control.FocusModel;
import javafx.scene.control.TitledPane;
import com.sun.javafx.scene.control.inputmap.InputMap;
import com.sun.javafx.scene.control.inputmap.KeyBinding;
import javafx.scene.input.KeyEvent;
import javafx.scene.input.MouseEvent;

import static javafx.scene.input.KeyCode.*;

public class AccordionBehavior extends BehaviorBase<Accordion> {

    private final InputMap<Accordion> inputMap;
    private AccordionFocusModel focusModel;
    
    public AccordionBehavior(Accordion accordion) {
        super(accordion);
        focusModel = new AccordionFocusModel(accordion);

        // create a map for accordion-specific mappings (this reuses the default
        // InputMap installed on the control, if it is non-null, allowing us to pick up any user-specified mappings)
        inputMap = createInputMap();

        // accordion-specific mappings for key and mouse input
        addDefaultMapping(inputMap,
                new InputMap.KeyMapping(UP, e -> pageUp(false)),
                new InputMap.KeyMapping(DOWN, e -> pageDown(false)),
                new InputMap.KeyMapping(LEFT, e -> {
                    if (isRTL(accordion)) pageDown(false);
                    else pageUp(false);
                }),
                new InputMap.KeyMapping(RIGHT, e -> {
                    if (isRTL(accordion)) pageUp(false);
                    else pageDown(false);
                }),
                new InputMap.KeyMapping(HOME, this::home),
                new InputMap.KeyMapping(END, this::end),
                new InputMap.KeyMapping(PAGE_UP, e -> pageUp(true)),
                new InputMap.KeyMapping(PAGE_DOWN, e -> pageDown(true)),
                new InputMap.KeyMapping(new KeyBinding(PAGE_UP).ctrl(), this::moveBackward),
                new InputMap.KeyMapping(new KeyBinding(PAGE_DOWN).ctrl(), this::moveForward),
                new InputMap.KeyMapping(new KeyBinding(TAB).ctrl(), this::moveForward),
                new InputMap.KeyMapping(new KeyBinding(TAB).ctrl().shift(), this::moveBackward),
                new InputMap.MouseMapping(MouseEvent.MOUSE_PRESSED, this::mousePressed)
        );
    }

    @Override public void dispose() {
        focusModel.dispose();
        super.dispose();
    }

    @Override public InputMap<Accordion> getInputMap() {
        return inputMap;
    }

    /***************************************************************************
     *                                                                         *
     * Key event handling                                                      *
     *                                                                         *
     **************************************************************************/

//    private static final String HOME = "Home";
//    private static final String END = "End";
//    private static final String PAGE_UP = "Page_Up";
//    private static final String PAGE_DOWN = "Page_Down";
//    private static final String CTRL_PAGE_UP = "Ctrl_Page_Up";
//    private static final String CTRL_PAGE_DOWN = "Ctrl_Page_Down";
//    private static final String CTRL_TAB = "Ctrl_Tab";
//    private static final String CTRL_SHIFT_TAB = "Ctrl_Shift_Tab";
//
//    protected static final List<KeyBinding> ACCORDION_BINDINGS = new ArrayList<KeyBinding>();
//    static {
//        ACCORDION_BINDINGS.add(new KeyBinding(KeyCode.UP, "TraverseUp"));
//        ACCORDION_BINDINGS.add(new KeyBinding(KeyCode.DOWN, "TraverseDown"));
//        ACCORDION_BINDINGS.add(new KeyBinding(KeyCode.LEFT, "TraverseLeft"));
//        ACCORDION_BINDINGS.add(new KeyBinding(KeyCode.RIGHT, "TraverseRight"));
//        ACCORDION_BINDINGS.add(new KeyBinding(KeyCode.HOME, HOME));
//        ACCORDION_BINDINGS.add(new KeyBinding(KeyCode.END, END));
//        ACCORDION_BINDINGS.add(new KeyBinding(KeyCode.PAGE_UP, PAGE_UP));
//        ACCORDION_BINDINGS.add(new KeyBinding(KeyCode.PAGE_DOWN, PAGE_DOWN));
//        ACCORDION_BINDINGS.add(new KeyBinding(KeyCode.PAGE_UP, CTRL_PAGE_UP).ctrl());
//        ACCORDION_BINDINGS.add(new KeyBinding(KeyCode.PAGE_DOWN, CTRL_PAGE_DOWN).ctrl());
//        ACCORDION_BINDINGS.add(new KeyBinding(KeyCode.TAB, CTRL_TAB).ctrl());
//        ACCORDION_BINDINGS.add(new KeyBinding(KeyCode.TAB, CTRL_SHIFT_TAB).shift().ctrl());
//    }

//    @Override protected void callAction(String name) {
//        Accordion accordion = getNode();
//        boolean rtl = (accordion.getEffectiveNodeOrientation() == NodeOrientation.RIGHT_TO_LEFT);
//
//        if (("TraverseLeft".equals(name) && !rtl) ||
//            ("TraverseRight".equals(name) && rtl) ||
//            "TraverseUp".equals(name) ||
//                PAGE_UP.equals(name)) {
//
//            if (focusModel.getFocusedIndex() != -1 && accordion.getPanes().get(focusModel.getFocusedIndex()).isFocused()) {
//                focusModel.focusPrevious();
//                int next = focusModel.getFocusedIndex();
//                accordion.getPanes().get(next).requestFocus();
//                if (PAGE_UP.equals(name)) {
//                    accordion.getPanes().get(next).setExpanded(true);
//                }
//            }
//        } else if (("TraverseRight".equals(name) && !rtl) ||
//                   ("TraverseLeft".equals(name) && rtl) ||
//                   "TraverseDown".equals(name) ||
//                PAGE_DOWN.equals(name)) {
//
//            if (focusModel.getFocusedIndex() != -1 && accordion.getPanes().get(focusModel.getFocusedIndex()).isFocused()) {
//                focusModel.focusNext();
//                int next = focusModel.getFocusedIndex();
//                accordion.getPanes().get(next).requestFocus();
//                if (PAGE_DOWN.equals(name)) {
//                    accordion.getPanes().get(next).setExpanded(true);
//                }
//            }
//        } else if (CTRL_TAB.equals(name) || CTRL_PAGE_DOWN.equals(name)) {
////            moveForward();
//        } else if (CTRL_SHIFT_TAB.equals(name) || CTRL_PAGE_UP.equals(name)) {
////            moveBackward();
//        } else if (HOME.equals(name)) {
////            home();
//        } else if (END.equals(name)) {
////            end();
//        } else {
//            super.callAction(name);
//        }
//    }

    private void pageUp(boolean doExpand) {
        Accordion accordion = getNode();
        if (focusModel.getFocusedIndex() != -1 && accordion.getPanes().get(focusModel.getFocusedIndex()).isFocused()) {
            focusModel.focusPrevious();
            int next = focusModel.getFocusedIndex();
            accordion.getPanes().get(next).requestFocus();
            if (doExpand) {
                accordion.getPanes().get(next).setExpanded(true);
            }
        }
    }

    private void pageDown(boolean doExpand) {
        Accordion accordion = getNode();
        if (focusModel.getFocusedIndex() != -1 && accordion.getPanes().get(focusModel.getFocusedIndex()).isFocused()) {
            focusModel.focusNext();
            int next = focusModel.getFocusedIndex();
            accordion.getPanes().get(next).requestFocus();
            if (doExpand) {
                accordion.getPanes().get(next).setExpanded(true);
            }
        }
    }

    private void moveBackward(KeyEvent e) {
        Accordion accordion = getNode();
        focusModel.focusPrevious();
        if (focusModel.getFocusedIndex() != -1) {
            int next = focusModel.getFocusedIndex();
            accordion.getPanes().get(next).requestFocus();
            accordion.getPanes().get(next).setExpanded(true);
        }
    }

    private void moveForward(KeyEvent e) {
        Accordion accordion = getNode();
        focusModel.focusNext();
        if (focusModel.getFocusedIndex() != -1) {
            int next = focusModel.getFocusedIndex();
            accordion.getPanes().get(next).requestFocus();
            accordion.getPanes().get(next).setExpanded(true);
        }
    }

    private void home(KeyEvent e) {
        Accordion accordion = getNode();
        if (focusModel.getFocusedIndex() != -1 && accordion.getPanes().get(focusModel.getFocusedIndex()).isFocused()) {
            TitledPane tp = accordion.getPanes().get(0);
            tp.requestFocus();
            tp.setExpanded(!tp.isExpanded());
        }
    }

    private void end(KeyEvent e) {
        Accordion accordion = getNode();
        if (focusModel.getFocusedIndex() != -1 && accordion.getPanes().get(focusModel.getFocusedIndex()).isFocused()) {
            TitledPane tp = accordion.getPanes().get(accordion.getPanes().size() - 1);
            tp.requestFocus();
            tp.setExpanded(!tp.isExpanded());
        }
    }


    /**
     * Mouse press over the background of the accordion
     * i.e. it missed all of the titled panes
     * select the last titled pane, or the accordion if
     * none present
     */
    public void mousePressed(MouseEvent e) {
        Accordion accordion = getNode();
        if (accordion.getPanes().size() > 0) {
            TitledPane lastTitledPane = accordion.getPanes().get(accordion.getPanes().size() - 1);
            lastTitledPane.requestFocus();
        }
        else {
            accordion.requestFocus();
        }
    }


    static class AccordionFocusModel extends FocusModel<TitledPane> {

        private final Accordion accordion;
        private final ChangeListener<Boolean> focusListener = new ChangeListener<Boolean>() {
            @Override
            public void changed(ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) {
                if (newValue) {
                    if (accordion.getExpandedPane() != null) {
                        accordion.getExpandedPane().requestFocus();
                    } else {
                        // TODO need to detect the focus direction
                        // to selected the first panel when TAB is pressed
                        // or select the last panel when SHIFT TAB is pressed.
                        if (! accordion.getPanes().isEmpty()) {
                            accordion.getPanes().get(0).requestFocus();
                        }
                    }
                }
            }
        };
        private final ChangeListener<Boolean> paneFocusListener = new ChangeListener<Boolean>() {
            @Override public void changed(ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) {
                if (newValue) {
                    final ReadOnlyBooleanProperty focusedProperty = (ReadOnlyBooleanProperty) observable;
                    final TitledPane tp = (TitledPane) focusedProperty.getBean();
                    focus(accordion.getPanes().indexOf(tp));
                }
            }
        };
        private final ListChangeListener<TitledPane> panesListener = c -> {
            while (c.next()) {
                if (c.wasAdded()) {
                    for (final TitledPane tp: c.getAddedSubList()) {
                        tp.focusedProperty().addListener(paneFocusListener);
                    }
                } else if (c.wasRemoved()) {
                    for (final TitledPane tp: c.getAddedSubList()) {
                        tp.focusedProperty().removeListener(paneFocusListener);
                    }
                }
            }
        };
        
        public AccordionFocusModel(final Accordion accordion) {
            if (accordion == null) {
                throw new IllegalArgumentException("Accordion can not be null");
            }
            this.accordion = accordion;
            this.accordion.focusedProperty().addListener(focusListener);
            this.accordion.getPanes().addListener(panesListener);
            for (final TitledPane tp: this.accordion.getPanes()) {
                tp.focusedProperty().addListener(paneFocusListener);
            }
        }

        void dispose() {
            accordion.focusedProperty().removeListener(focusListener);
            accordion.getPanes().removeListener(panesListener);
            for (final TitledPane tp: this.accordion.getPanes()) {
                tp.focusedProperty().removeListener(paneFocusListener);
            }
        }

        @Override
        protected int getItemCount() {
            final ObservableList<TitledPane> panes = accordion.getPanes();
            return panes == null ? 0 : panes.size();
        }

        @Override
        protected TitledPane getModelItem(int row) {
            final ObservableList<TitledPane> panes = accordion.getPanes();
            if (panes == null) return null;
            if (row < 0) return null;
            return panes.get(row%panes.size());
        }

        @Override public void focusPrevious() {
            if (getFocusedIndex() <= 0) {
                focus(accordion.getPanes().size() - 1);
            } else {
                focus((getFocusedIndex() - 1)%accordion.getPanes().size());
            }
        }

        @Override public void focusNext() {
            if (getFocusedIndex() == -1) {
                focus(0);
            } else {
                focus((getFocusedIndex() + 1)%accordion.getPanes().size());
            }
        }
    }
}