// This Source Code is in the Public Domain per: http://unlicense.org
package org.litesoft.GWT.client.widgets.nonpublic;

import org.litesoft.GWT.client.*;
import org.litesoft.commonfoundation.typeutils.*;
import org.litesoft.ui.*;

import com.google.gwt.user.client.*;
import com.google.gwt.user.client.ui.*;

public class AbstractCssBackgroundButtonHelper implements OnBrowserEventListener {
    private static final State sREGULAR = new State( "Regular" );
    private static final State sMOUSEOVER = new State( "Mouseover" );
    private static final State sMOUSEDOWN = new State( "Mousedown" );
    private static final State sDISABLED = new State( "Disabled" );

    public static final State[] ALL_STATES = new State[]{sREGULAR, sMOUSEOVER, sMOUSEDOWN, sDISABLED};

    private boolean mMouseOver = false;
    private boolean mMouseDown = false;
    private boolean mDisabled = false;
    protected Widget mWidget;
    private String mEnabledToolTip;
    private String mDisabledToolTip = null;
    protected State mCurrentState = null;
    private Element mSavedCaptureElement = null;

    public AbstractCssBackgroundButtonHelper( OnBrowserEventListenable pListenable, String pEnabledToolTip, String pDisabledToolTip ) {
        mWidget = pListenable.getOnBrowserEventListenableWidget();

        if ( null != (mEnabledToolTip = Strings.noEmpty( pEnabledToolTip )) ) {
            mWidget.setTitle( mEnabledToolTip );
            mDisabledToolTip = pDisabledToolTip == null ? pDisabledToolTip : pDisabledToolTip.trim();
        }
        pListenable.setOnBrowserEventListener( Event.MOUSEEVENTS, this );
    }

    public String getEnabledToolTip() {
        return mEnabledToolTip;
    }

    public void setEnabledToolTip( String pEnabledToolTip ) {
        String zEnabledToolTip = Strings.noEmpty( pEnabledToolTip );
        if ( zEnabledToolTip != null ) {
            mEnabledToolTip = pEnabledToolTip;
            if ( isEnabled() ) {
                mWidget.setTitle( mEnabledToolTip );
            }
        }
    }

    private State determineNewForm() {
        if ( mDisabled ) {
            return sDISABLED;
        }
        if ( mMouseDown ) {
            return sMOUSEDOWN;
        }
        if ( mMouseOver ) {
            return sMOUSEOVER;
        }
        return sREGULAR;
    }

    public AbstractCssBackgroundButtonHelper updateForm() {
        State zNewForm = determineNewForm();
        if ( mCurrentState != zNewForm ) {
            if ( mCurrentState != null ) {
                removeCurrentState();

                if ( mCurrentState == sMOUSEDOWN ) {
                    DOM.releaseCapture( mWidget.getElement() );
                    if ( mSavedCaptureElement != null ) {
                        DOM.setCapture( mSavedCaptureElement );
                        mSavedCaptureElement = null;
                    }
                }
            }
            String zNewToolTip = mDisabledToolTip;
            if ( zNewForm != sDISABLED ) {
                zNewToolTip = mEnabledToolTip;
                if ( zNewForm == sMOUSEDOWN ) {
                    mSavedCaptureElement = DOM.getCaptureElement();
                    if ( mSavedCaptureElement != null ) {
                        DOM.releaseCapture( mSavedCaptureElement );
                    }
                    DOM.setCapture( mWidget.getElement() );
                }
            }
            mCurrentState = zNewForm;
            applyCurrentState();
            if ( zNewToolTip != null ) {
                mWidget.setTitle( zNewToolTip );
            }
        }
        return this;
    }

    protected void applyCurrentState() {
        mWidget.addStyleName( "" + mCurrentState );
    }

    protected void removeCurrentState() {
        mWidget.removeStyleName( "" + mCurrentState );
    }

    public boolean isEnabled() {
        return !mDisabled;
    }

    public void setEnabled( boolean pEnabled ) {
        mDisabled = !pEnabled;
        updateForm();
    }

    @Override
    public boolean onBrowserEvent( Event pEvent ) {
        switch ( DOM.eventGetType( pEvent ) ) {
            case Event.ONMOUSEDOWN:
                UtilsGwt.eventPreventDefaultAndCancelBubble( pEvent );
                onMouseDown( pEvent );
                break;
            case Event.ONMOUSEUP:
                onMouseUp( pEvent );
                break;
            case Event.ONMOUSEOVER:
                onMouseEnter( pEvent );
                break;
            case Event.ONMOUSEOUT:
                onMouseLeave( pEvent );
                break;
            case Event.ONMOUSEMOVE:
                UtilsGwt.eventPreventDefaultAndCancelBubble( pEvent );
            default:
                break;
        }
        return !isEnabled();
    }

    protected void onMouseDown( Event pEvent ) {
        mouseDown();
    }

    protected void onMouseUp( Event pEvent ) {
        mouseUp();
    }

    protected void onMouseEnter( Event pEvent ) {
        mouseEnter();
    }

    protected void onMouseLeave( Event pEvent ) {
        mouseLeave();
    }

    protected void mouseDown() {
        mMouseDown = true;
        updateForm();
    }

    protected void mouseUp() {
        mMouseDown = false;
        updateForm();
    }

    protected void mouseEnter() {
        mMouseOver = true;
        updateForm();
    }

    protected void mouseLeave() {
        mMouseOver = false;
        updateForm();
    }

    public static class State {
        private String mText;

        public State( String pText ) {
            mText = pText;
        }

        @Override
        public String toString() {
            return mText;
        }

        public String getURL( String pURLBaseGifExtentionAssumed ) {
            return pURLBaseGifExtentionAssumed + "-" + mText + ".gif";
        }

        public String[] getURLsFor9cell( String pURLBaseGifExtentionAssumed ) {
            return generateURLs( pURLBaseGifExtentionAssumed + "/" + mText + "/", CompassPoint.values() );
        }

        private String[] generateURLs( String pLeader, CompassPoint[] pCells ) {
            String[] rv = new String[pCells.length];
            for ( int i = 0; i < pCells.length; i++ ) {
                rv[i] = pLeader + pCells[i] + ".gif";
            }
            return rv;
        }
    }
}