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

import com.google.gwt.event.dom.client.*;
import com.google.gwt.gen2.table.client.*;
import com.google.gwt.user.client.*;

import java.util.*;

public interface TableHelper {
    public abstract static class GridHelper {
        private final HTMLTable mGrid;

        public GridHelper( HTMLTable pGrid ) {
            mGrid = pGrid;
        }

        public int getRowForEvent( Event pEvent ) {
            Element targetCell = mGrid.getEventTargetCell( pEvent );
            return (targetCell != null) ? getRowIndex( DOM.getParent( targetCell ) ) : -1;
        }

        public Cell getCellForEvent( Event pEvent ) {
            Element targetCell = mGrid.getEventTargetCell( pEvent );
            if ( targetCell != null ) {
                Element targetRow = DOM.getParent( targetCell );
                int row = getRowIndex( targetRow );
                int col = getCellIndex( targetRow, targetCell );
                if ( col != -1 ) {
                    return new Cell( row, col );
                }
            }
            return null;
        }

        protected abstract int getRowIndex( Element pRowElement );

        protected abstract int getCellIndex( Element pRowElement, Element pCellElement );
    }

    public static abstract class GridClickHandler<RowType> implements ClickHandler {
        private final List<ColumnDefinition<RowType, ?>> mColDefs;
        private final GridHelper mGridHelper;
        private final int mFirstRowOffset;

        public GridClickHandler( int pFirstRowOffset, GridHelper pGridHelper, List<ColumnDefinition<RowType, ?>> pColDefs ) {
            mFirstRowOffset = pFirstRowOffset;
            mGridHelper = pGridHelper;
            mColDefs = pColDefs;
        }

        @SuppressWarnings("unchecked")
        public void onClick( ClickEvent pEvent ) {
            Cell cell = mGridHelper.getCellForEvent( Event.as( pEvent.getNativeEvent() ) );
            if ( cell != null ) {
                ColumnDefinition<RowType, ?> colDef = mColDefs.get( cell.getCol() );
                ClickHandlerProperty zProperty = colDef.getColumnProperty( ClickHandlerProperty.TYPE );
                if ( zProperty != null ) {
                    CellClickHandler<?> clickHandler = zProperty.getValue();
                    if ( clickHandler != null ) {
                        int rowIndex = cell.getRow() - mFirstRowOffset; // Mat, I updated this to remove the overhead on the Accordion table
                        if ( rowIndex >= 0 ) {
                            RowType rowValue = getRowValue( rowIndex );
                            ((CellClickHandler<RowType>) clickHandler).execute( colDef, rowIndex, rowValue );
                        }
                    }
                }
                pEvent.stopPropagation();
            }
        }

        protected abstract RowType getRowValue( int pRow );
    }

    public static class Cell {
        private final int mRow;
        private final int mCol;

        public Cell( int pRow, int pCol ) {
            mRow = pRow;
            mCol = pCol;
        }

        public int getRow() {
            return mRow;
        }

        public int getCol() {
            return mCol;
        }
    }
}