// This Source Code is in the Public Domain per: http://litesoft.org/License.txt
package org.litesoft.GWT.forms.client.components.impls.input;

import java.util.*;

import org.litesoft.GWT.client.*;
import org.litesoft.GWT.client.widgets.*;
import org.litesoft.GWT.forms.client.components.*;
import org.litesoft.GWT.forms.client.components.nonpublic.*;
import org.litesoft.core.simpletypes.*;
import org.litesoft.core.typeutils.*;
import org.litesoft.ui.*;
import org.litesoft.uispecification.*;

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

public class FormComboBox extends AbstractFocusWidgetErrorableFormElement
{
    public FormComboBox( String pFieldLabel, UiFont pLabelFont, String pTooltip, FormComboBoxFocusWidget pComboBox, boolean pAddStyle )
    {
        super( pComboBox, pTooltip, "frmCmbBox", pAddStyle );
        initialize( pFieldLabel, pLabelFont, pTooltip );
    }

    public FormComboBox( String pFieldLabel, UiFont pLabelFont, String pTooltip, SimpleKeyValuePair pOptionZero )
    {
        this( pFieldLabel, pLabelFont, pTooltip, new NativeFormComboBox(), false );
        addItem( pOptionZero );
    }

    public FormComboBox( String pFieldLabel, UiFont pLabelFont, String pTooltip, String pOptionZero )
    {
        this( pFieldLabel, pLabelFont, pTooltip, convertToKeyValuePair( pOptionZero ) );
    }

    public FormComboBox( String pFieldLabel, UiFont pLabelFont, String pTooltip )
    {
        this( pFieldLabel, pLabelFont, pTooltip, (SimpleKeyValuePair) null );
    }

    @Override
    protected void initialize( String pFieldLabel, UiFont pLabelFont, String pTooltip )
    {
        super.initialize( pFieldLabel, pLabelFont, pTooltip );

        getComboBox().addChangeHandler( new ChangeHandler()
        {
            @Override
            public void onChange( ChangeEvent event )
            {
                fireChangeListeners();
            }
        } );
    }

    // SizeManaged

    @Override
    public void relayout()
    {
        Widget parent = getParent();
        if ( parent instanceof SizeManaged )
        {
            ((SizeManaged) parent).relayout();
        }
    }

    // IFormComponent

    @Override
    public Object getCurrentValue()
    {
        return getSelectedKeyValuePair();
    }

    @Override
    public void setCurrentValue( Object pNewValue )
    {
        if ( pNewValue != null )
        {
            if ( pNewValue instanceof String )
            {
                setSelected( (String) pNewValue );
                return;
            }
            if ( pNewValue instanceof SimpleKeyValuePair )
            {
                setSelected( (SimpleKeyValuePair) pNewValue );
                return;
            }
            throw new IllegalArgumentException( "Not a String or a SimpleKeyValuePair, but a '" + pNewValue.getClass() + "': " + pNewValue );
        }
    }

    // Support...

    @Override
    public void simulateUserTextEntry( String pText )
    {
        int zCurrentSelected = getSelectedIndex();
        setSelectedIndex( determineItemToSelect( Strings.deNull( pText ).trim() ) );
        if ( zCurrentSelected != getSelectedIndex() )
        {
            fireChangeListeners();
        }
        pullFocusTo( (Focusable) getComboBox() );
    }

    private int determineItemToSelect( String pText )
    {
        FormComboBoxFocusWidget zCB = getComboBox();
        for ( int zIndex = zCB.getItemCount(); --zIndex >= 0; )
        {
            String zValue = zCB.getValue( zIndex );
            String zKeyPairValue = mManager.getPairBySubmitValue( zValue ).toStringValue();
            if ( pText.equals( Strings.deNull( zKeyPairValue ).trim() ) )
            {
                return zIndex;
            }
        }
        throw new IllegalArgumentException( "simulateUserTextEntry on '" + mFieldLabel + "' to:" + pText );
    }

    public FormComboBox addItems( String... pKeyAndDisplayValues )
    {
        if ( pKeyAndDisplayValues != null )
        {
            for ( String zKeyAndDisplayValue : pKeyAndDisplayValues )
            {
                addItem( zKeyAndDisplayValue );
            }
        }
        return this;
    }

    public FormComboBox addItems( SimpleKeyValuePair... pKeyValuePairs )
    {
        if ( pKeyValuePairs != null )
        {
            for ( SimpleKeyValuePair zKeyValuePair : pKeyValuePairs )
            {
                addItem( zKeyValuePair );
            }
        }
        return this;
    }

    public void setSelected( String pKeyAndDisplayValue )
    {
        setSelected( convertToKeyValuePair( pKeyAndDisplayValue ) );
    }

    public void addItem( String pKeyAndDisplayValue )
    {
        addItem( convertToKeyValuePair( pKeyAndDisplayValue ) );
    }

    public void removeItem( String pKeyAndDisplayValue )
    {
        removeItem( convertToKeyValuePair( pKeyAndDisplayValue ) );
    }

    public void setSelected( String pKey, String pDisplayValue )
    {
        setSelected( convertToKeyValuePair( pKey, pDisplayValue ) );
    }

    public void addItem( String pKey, String pDisplayValue )
    {
        addItem( convertToKeyValuePair( pKey, pDisplayValue ) );
    }

    public void removeItem( String pKey, String pDisplayValue )
    {
        removeItem( convertToKeyValuePair( pKey, pDisplayValue ) );
    }

    public void setSelected( SimpleKeyValuePair pNewSelectedKeyValuePair )
    {
        int zIx = -1;
        if ( pNewSelectedKeyValuePair != null )
        {
            if ( -1 == (zIx = indexOf( pNewSelectedKeyValuePair )) )
            {
                addItem( pNewSelectedKeyValuePair );
                zIx = indexOf( pNewSelectedKeyValuePair );
            }
        }
        setSelectedIndex( zIx );
    }

    public void addItem( SimpleKeyValuePair pKeyValuePair )
    {
        if ( pKeyValuePair != null )
        {
            String zComboBoxDisplayValue = pKeyValuePair.toStringValue();
            String zComboBoxSubmitValue = "" + (++mLastComboBoxSubmitValue);
            addItemToComboBox( zComboBoxDisplayValue, zComboBoxSubmitValue );
            mManager.add( zComboBoxSubmitValue, pKeyValuePair );
        }
    }

    public void removeItem( SimpleKeyValuePair pKeyValuePair )
    {
        int at = indexOf( pKeyValuePair );
        if ( at != -1 )
        {
            removeItemFromComboBox( at );
            mManager.remove( pKeyValuePair );
        }
    }

    public SimpleKeyValuePair getSelectedKeyValuePair()
    {
        int zIx = getSelectedIndex();
        if ( zIx == -1 )
        {
            return null;
        }
        String zSelectedSubmitValue = getSubmitValueFromComboBox( zIx );
        return mManager.getPairBySubmitValue( zSelectedSubmitValue );
    }

    private int mLastComboBoxSubmitValue = 0;
    private PairSubmitValueManager mManager = new PairSubmitValueManager();

    private int indexOf( SimpleKeyValuePair pKeyValuePair )
    {
        if ( pKeyValuePair != null )
        {
            String zComboBoxSubmitValue = mManager.getSubmitValueByPair( pKeyValuePair );
            if ( zComboBoxSubmitValue != null )
            {
                int zItemCount = getItemCountFromComboBox();
                for ( int i = 0; i < zItemCount; i++ )
                {
                    String zSubmitValue = getSubmitValueFromComboBox( i );
                    if ( zComboBoxSubmitValue.equals( zSubmitValue ) )
                    {
                        return i;
                    }
                }
            }
        }
        return -1;
    }

    public int getSelectedIndex()
    {
        try
        {
            return getComboBox().getSelectedIndex();
        }
        catch ( RuntimeException e )
        {
            errorFromComboBox( "getSelectedIndex", e );
            return -1;
        }
    }

    public void setSelectedIndex( int pSelectedIndex )
    {
        try
        {
            getComboBox().setSelectedIndex( pSelectedIndex );
        }
        catch ( RuntimeException e )
        {
            errorFromComboBox( "setSelectedIndex", e );
        }
    }

    private int getItemCountFromComboBox()
    {
        try
        {
            return getComboBox().getItemCount();
        }
        catch ( RuntimeException e )
        {
            errorFromComboBox( "getItemCountFromComboBox", e );
            return 0;
        }
    }

    private void addItemToComboBox( String pComboBoxDisplayValue, String pComboBoxSubmitValue )
    {
        try
        {
            getComboBox().addItem( pComboBoxDisplayValue, pComboBoxSubmitValue );
        }
        catch ( RuntimeException e )
        {
            errorFromComboBox( "addItemToComboBox", e );
        }
    }

    private void removeItemFromComboBox( int pAt )
    {
        try
        {
            getComboBox().removeItem( pAt );
        }
        catch ( RuntimeException e )
        {
            errorFromComboBox( "removeItemFromComboBox", e );
        }
    }

    private String getSubmitValueFromComboBox( int pAt )
    {
        try
        {
            return getComboBox().getValue( pAt );
        }
        catch ( RuntimeException e )
        {
            errorFromComboBox( "getSubmitValueFromComboBox", e );
            return null;
        }
    }

    public FormComboBoxFocusWidget getComboBox()
    {
        return (FormComboBoxFocusWidget) mInputWidget;
    }

    public boolean areOptionsAlwaysUpdatable()
    {
        return (mInputWidget instanceof ComboBoxOptionsAlwaysUpdatable);
    }

    private void errorFromComboBox( String pWhat, RuntimeException pRTE )
    {
        String zComboBoxType = Objects.justClassNameOf( mInputWidget );
        String zBody = "There was a problem with the FormComboBox\n" +//
                       "    interacting with " + zComboBoxType + "\n" +//
                       "       thru " + pWhat;
        AlertManager.alert( "FormComboBox", "Error", zBody, pRTE );
    }

    private static SimpleKeyValuePair convertToKeyValuePair( String pKeyAndDisplayValue )
    {
        return (pKeyAndDisplayValue != null) ? convertToKeyValuePair( pKeyAndDisplayValue, pKeyAndDisplayValue ) : null;
    }

    private static SimpleKeyValuePair convertToKeyValuePair( String pKey, String pDisplayValue )
    {
        return new StringKeyValuePair( pKey, pDisplayValue );
    }

    private static class PairSubmitValueManager
    {
        private Map mComboBoxSubmitValuesToPairs = new HashMap();
        private Map mPairKeysToComboBoxSubmitValues = new HashMap();

        public void remove( SimpleKeyValuePair pKeyValuePair )
        {
            String zComboBoxSubmitValue = (String) mPairKeysToComboBoxSubmitValues.remove( pKeyValuePair.getKey() );
            mComboBoxSubmitValuesToPairs.remove( zComboBoxSubmitValue );
        }

        public void add( String pComboBoxSubmitValue, SimpleKeyValuePair pKeyValuePair )
        {
            //noinspection unchecked
            mPairKeysToComboBoxSubmitValues.put( pKeyValuePair.getKey(), pComboBoxSubmitValue );
            //noinspection unchecked
            mComboBoxSubmitValuesToPairs.put( pComboBoxSubmitValue, pKeyValuePair );
        }

        public SimpleKeyValuePair getPairBySubmitValue( String pComboBoxSubmitValue )
        {
            return (SimpleKeyValuePair) mComboBoxSubmitValuesToPairs.get( pComboBoxSubmitValue );
        }

        public String getSubmitValueByPair( SimpleKeyValuePair pKeyValuePair )
        {
            return (String) mPairKeysToComboBoxSubmitValues.get( pKeyValuePair.getKey() );
        }
    }
}