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package com.sun.java.swing.plaf.windows;

import java.security.AccessController;
import sun.security.action.GetBooleanAction;

import java.util.*;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeEvent;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;


import com.sun.java.swing.plaf.windows.TMSchema.State;
import static com.sun.java.swing.plaf.windows.TMSchema.State.*;
import com.sun.java.swing.plaf.windows.TMSchema.Part;
import com.sun.java.swing.plaf.windows.TMSchema.Prop;
import com.sun.java.swing.plaf.windows.XPStyle.Skin;

import sun.awt.AppContext;

A class to help mimic Vista theme animations.  The only kind of
animation it handles for now is 'transition' animation (this seems
to be the only animation which Vista theme can do). This is when
one picture fadein over another one in some period of time.
According to
https://connect.microsoft.com/feedback/ViewFeedback.aspx?FeedbackID=86852&SiteID=4
The animations are all linear.
This class has a number of responsibilities.

  
 It trigger rapaint for the UI components involved in the animation
  
 It tracks the animation state for every UI component involved in the animation and paints Skin in new State over the Skin in last State using AlphaComposite.SrcOver.derive(alpha) where {code alpha} depends on the state of animation 
Author:
Igor Kushnirskiy/**
 * A class to help mimic Vista theme animations.  The only kind of
 * animation it handles for now is 'transition' animation (this seems
 * to be the only animation which Vista theme can do). This is when
 * one picture fadein over another one in some period of time.
 * According to
 * https://connect.microsoft.com/feedback/ViewFeedback.aspx?FeedbackID=86852&SiteID=4
 * The animations are all linear.
 *
 * This class has a number of responsibilities.
 * <ul>
 *   <li> It trigger rapaint for the UI components involved in the animation
 *   <li> It tracks the animation state for every UI component involved in the
 *        animation and paints {@code Skin} in new {@code State} over the
 *        {@code Skin} in last {@code State} using
 *        {@code AlphaComposite.SrcOver.derive(alpha)} where {code alpha}
 *        depends on the state of animation
 * </ul>
 *
 * @author Igor Kushnirskiy
 */
class AnimationController implements ActionListener, PropertyChangeListener {

    private static final boolean VISTA_ANIMATION_DISABLED =
        AccessController.doPrivileged(new GetBooleanAction("swing.disablevistaanimation"));


    private static final Object ANIMATION_CONTROLLER_KEY =
        new StringBuilder("ANIMATION_CONTROLLER_KEY");

    private final Map<JComponent, Map<Part, AnimationState>> animationStateMap =
            new WeakHashMap<JComponent, Map<Part, AnimationState>>();

    //this timer is used to cause repaint on animated components
    //30 repaints per second should give smooth animation affect
    private final javax.swing.Timer timer =
        new javax.swing.Timer(1000/30, this);

    private static synchronized AnimationController getAnimationController() {
        AppContext appContext = AppContext.getAppContext();
        Object obj = appContext.get(ANIMATION_CONTROLLER_KEY);
        if (obj == null) {
            obj = new AnimationController();
            appContext.put(ANIMATION_CONTROLLER_KEY, obj);
        }
        return (AnimationController) obj;
    }

    private AnimationController() {
        timer.setRepeats(true);
        timer.setCoalesce(true);
        //we need to dispose the controller on l&f change
        UIManager.addPropertyChangeListener(this);
    }

    private static void triggerAnimation(JComponent c,
                           Part part, State newState) {
        if (c instanceof javax.swing.JTabbedPane
            || part == Part.TP_BUTTON) {
            //idk: we can not handle tabs animation because
            //the same (component,part) is used to handle all the tabs
            //and we can not track the states
            //Vista theme might have transition duration for toolbar buttons
            //but native application does not seem to animate them
            return;
        }
        AnimationController controller =
            AnimationController.getAnimationController();
        State oldState = controller.getState(c, part);
        if (oldState != newState) {
            controller.putState(c, part, newState);
            if (newState == State.DEFAULTED) {
                // it seems for DEFAULTED button state Vista does animation from
                // HOT
                oldState = State.HOT;
            }
            if (oldState != null) {
                long duration;
                if (newState == State.DEFAULTED) {
                    //Only button might have DEFAULTED state
                    //idk: do not know how to get the value from Vista
                    //one second seems plausible value
                    duration = 1000;
                } else {
                    XPStyle xp = XPStyle.getXP();
                    duration = (xp != null)
                               ? xp.getThemeTransitionDuration(
                                       c, part,
                                       normalizeState(oldState),
                                       normalizeState(newState),
                                       Prop.TRANSITIONDURATIONS)
                               : 1000;
                }
                controller.startAnimation(c, part, oldState, newState, duration);
            }
        }
    }

    // for scrollbar up, down, left and right button pictures are
    // defined by states.  It seems that theme has duration defined
    // only for up button states thus we doing this translation here.
    private static State normalizeState(State state) {
        State rv;
        switch (state) {
        case DOWNPRESSED:
            /* falls through */
        case LEFTPRESSED:
            /* falls through */
        case RIGHTPRESSED:
            rv = UPPRESSED;
            break;

        case DOWNDISABLED:
            /* falls through */
        case LEFTDISABLED:
            /* falls through */
        case RIGHTDISABLED:
            rv = UPDISABLED;
            break;

        case DOWNHOT:
            /* falls through */
        case LEFTHOT:
            /* falls through */
        case RIGHTHOT:
            rv = UPHOT;
            break;

        case DOWNNORMAL:
            /* falls through */
        case LEFTNORMAL:
            /* falls through */
        case RIGHTNORMAL:
            rv = UPNORMAL;
            break;

        default :
            rv = state;
            break;
        }
        return rv;
    }

    private synchronized State getState(JComponent component, Part part) {
        State rv = null;
        Object tmpObject =
            component.getClientProperty(PartUIClientPropertyKey.getKey(part));
        if (tmpObject instanceof State) {
            rv = (State) tmpObject;
        }
        return rv;
    }

    private synchronized void putState(JComponent component, Part part,
                                       State state) {
        component.putClientProperty(PartUIClientPropertyKey.getKey(part),
                                    state);
    }

    private synchronized void startAnimation(JComponent component,
                                     Part part,
                                     State startState,
                                     State endState,
                                     long millis) {
        boolean isForwardAndReverse = false;
        if (endState == State.DEFAULTED) {
            isForwardAndReverse = true;
        }
        Map<Part, AnimationState> map = animationStateMap.get(component);
        if (millis <= 0) {
            if (map != null) {
                map.remove(part);
                if (map.size() == 0) {
                    animationStateMap.remove(component);
                }
            }
            return;
        }
        if (map == null) {
            map = new EnumMap<Part, AnimationState>(Part.class);
            animationStateMap.put(component, map);
        }
        map.put(part,
                new AnimationState(startState, millis, isForwardAndReverse));
        if (! timer.isRunning()) {
            timer.start();
        }
    }

    static void paintSkin(JComponent component, Skin skin,
                      Graphics g, int dx, int dy, int dw, int dh, State state) {
        if (VISTA_ANIMATION_DISABLED) {
            skin.paintSkinRaw(g, dx, dy, dw, dh, state);
            return;
        }
        triggerAnimation(component, skin.part, state);
        AnimationController controller = getAnimationController();
        synchronized (controller) {
            AnimationState animationState = null;
            Map<Part, AnimationState> map =
                controller.animationStateMap.get(component);
            if (map != null) {
                animationState = map.get(skin.part);
            }
            if (animationState != null) {
                animationState.paintSkin(skin, g, dx, dy, dw, dh, state);
            } else {
                skin.paintSkinRaw(g, dx, dy, dw, dh, state);
            }
        }
    }

    public synchronized void propertyChange(PropertyChangeEvent e) {
        if ("lookAndFeel" == e.getPropertyName()
            && ! (e.getNewValue() instanceof WindowsLookAndFeel) ) {
            dispose();
        }
    }

    public synchronized void actionPerformed(ActionEvent e) {
        java.util.List<JComponent> componentsToRemove = null;
        java.util.List<Part> partsToRemove = null;
        for (JComponent component : animationStateMap.keySet()) {
            component.repaint();
            if (partsToRemove != null) {
                partsToRemove.clear();
            }
            Map<Part, AnimationState> map = animationStateMap.get(component);
            if (! component.isShowing()
                  || map == null
                  || map.size() == 0) {
                if (componentsToRemove == null) {
                    componentsToRemove = new ArrayList<JComponent>();
                }
                componentsToRemove.add(component);
                continue;
            }
            for (Part part : map.keySet()) {
                if (map.get(part).isDone()) {
                    if (partsToRemove == null) {
                        partsToRemove = new ArrayList<Part>();
                    }
                    partsToRemove.add(part);
                }
            }
            if (partsToRemove != null) {
                if (partsToRemove.size() == map.size()) {
                    //animation is done for the component
                    if (componentsToRemove == null) {
                        componentsToRemove = new ArrayList<JComponent>();
                    }
                    componentsToRemove.add(component);
                } else {
                    for (Part part : partsToRemove) {
                        map.remove(part);
                    }
                }
            }
        }
        if (componentsToRemove != null) {
            for (JComponent component : componentsToRemove) {
                animationStateMap.remove(component);
            }
        }
        if (animationStateMap.size() == 0) {
            timer.stop();
        }
    }

    private synchronized void dispose() {
        timer.stop();
        UIManager.removePropertyChangeListener(this);
        synchronized (AnimationController.class) {
            AppContext.getAppContext()
                .put(ANIMATION_CONTROLLER_KEY, null);
        }
    }

    private static class AnimationState {
        private final State startState;

        //animation duration in nanoseconds
        private final long duration;

        //animatin start time in nanoseconds
        private long startTime;

        //direction the alpha value is changing
        //forward  - from 0 to 1
        //!forward - from 1 to 0
        private boolean isForward = true;

        //if isForwardAndReverse the animation continually goes
        //forward and reverse. alpha value is changing from 0 to 1 then
        //from 1 to 0 and so forth
        private boolean isForwardAndReverse;

        private float progress;

        AnimationState(final State startState,
                       final long milliseconds,
                       boolean isForwardAndReverse) {
            assert startState != null && milliseconds > 0;
            assert SwingUtilities.isEventDispatchThread();

            this.startState = startState;
            this.duration = milliseconds * 1000000;
            this.startTime = System.nanoTime();
            this.isForwardAndReverse = isForwardAndReverse;
            progress = 0f;
        }
        private void updateProgress() {
            assert SwingUtilities.isEventDispatchThread();

            if (isDone()) {
                return;
            }
            long currentTime = System.nanoTime();

            progress = ((float) (currentTime - startTime))
                / duration;
            progress = Math.max(progress, 0); //in case time was reset
            if (progress >= 1) {
                progress = 1;
                if (isForwardAndReverse) {
                    startTime = currentTime;
                    progress = 0;
                    isForward = ! isForward;
                }
            }
        }
        void paintSkin(Skin skin, Graphics _g,
                       int dx, int dy, int dw, int dh, State state) {
            assert SwingUtilities.isEventDispatchThread();

            updateProgress();
            if (! isDone()) {
                Graphics2D g = (Graphics2D) _g.create();
                if (skin.haveToSwitchStates()) {
                    skin.paintSkinRaw(g, dx, dy, dw, dh, state);
                    g.setComposite(AlphaComposite.SrcOver.derive(1 - progress));
                    skin.paintSkinRaw(g, dx, dy, dw, dh, startState);
                } else {
                    skin.paintSkinRaw(g, dx, dy, dw, dh, startState);
                    float alpha;
                    if (isForward) {
                        alpha = progress;
                    } else {
                        alpha = 1 - progress;
                    }
                    g.setComposite(AlphaComposite.SrcOver.derive(alpha));
                    skin.paintSkinRaw(g, dx, dy, dw, dh, state);
                }
                g.dispose();
            } else {
                skin.paintSkinRaw(_g, dx, dy, dw, dh, state);
                skin.switchStates(false);
            }
        }
        boolean isDone() {
            assert SwingUtilities.isEventDispatchThread();

            return  progress >= 1;
        }
    }

    private static class PartUIClientPropertyKey
          implements UIClientPropertyKey {

        private static final Map<Part, PartUIClientPropertyKey> map =
            new EnumMap<Part, PartUIClientPropertyKey>(Part.class);

        static synchronized PartUIClientPropertyKey getKey(Part part) {
            PartUIClientPropertyKey rv = map.get(part);
            if (rv == null) {
                rv = new PartUIClientPropertyKey(part);
                map.put(part, rv);
            }
            return rv;
        }

        private final Part part;
        private PartUIClientPropertyKey(Part part) {
            this.part  = part;
        }
        public String toString() {
            return part.toString();
        }
    }
}