/* ====================================================================
   Licensed to the Apache Software Foundation (ASF) under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
==================================================================== */
package org.apache.poi.hwpf.usermodel;

import org.apache.poi.hwpf.model.FieldDescriptor;
import org.apache.poi.hwpf.model.PlexOfField;
import org.apache.poi.util.Internal;

/**
 * TODO: document me
 * 
 * @author Sergey Vladimirov (vlsergey {at} gmail {dot} com)
 */
@Internal
class FieldImpl implements Field
{
    private PlexOfField endPlex;
    private PlexOfField separatorPlex;
    private PlexOfField startPlex;

    public FieldImpl( PlexOfField startPlex, PlexOfField separatorPlex,
            PlexOfField endPlex )
    {
        if ( startPlex == null )
            throw new IllegalArgumentException( "startPlex == null" );
        if ( endPlex == null )
            throw new IllegalArgumentException( "endPlex == null" );

        if ( startPlex.getFld().getBoundaryType() != FieldDescriptor.FIELD_BEGIN_MARK )
            throw new IllegalArgumentException( "startPlex (" + startPlex
                    + ") is not type of FIELD_BEGIN" );

        if ( separatorPlex != null
                && separatorPlex.getFld().getBoundaryType() != FieldDescriptor.FIELD_SEPARATOR_MARK )
            throw new IllegalArgumentException( "separatorPlex" + separatorPlex
                    + ") is not type of FIELD_SEPARATOR" );

        if ( endPlex.getFld().getBoundaryType() != FieldDescriptor.FIELD_END_MARK )
            throw new IllegalArgumentException( "endPlex (" + endPlex
                    + ") is not type of FIELD_END" );

        this.startPlex = startPlex;
        this.separatorPlex = separatorPlex;
        this.endPlex = endPlex;
    }

    public Range firstSubrange( Range parent )
    {
        if ( hasSeparator() )
        {
            if ( getMarkStartOffset() + 1 == getMarkSeparatorOffset() )
                return null;

            return new Range( getMarkStartOffset() + 1,
                    getMarkSeparatorOffset(), parent )
            {
                @Override
                public String toString()
                {
                    return "FieldSubrange1 (" + super.toString() + ")";
                }
            };
        }

        if ( getMarkStartOffset() + 1 == getMarkEndOffset() )
            return null;

        return new Range( getMarkStartOffset() + 1, getMarkEndOffset(), parent )
        {
            @Override
            public String toString()
            {
                return "FieldSubrange1 (" + super.toString() + ")";
            }
        };
    }

    /**
     * @return character position of first character after field (i.e.
     *         {@link #getMarkEndOffset()} + 1)
     */
    public int getFieldEndOffset()
    {
        /*
         * sometimes plex looks like [100, 2000), where 100 is the position of
         * field-end character, and 2000 - some other char position, far away
         * from field (not inside). So taking into account only start --sergey
         */
        return endPlex.getFcStart() + 1;
    }

    /**
     * @return character position of first character in field (i.e.
     *         {@link #getFieldStartOffset()})
     */
    public int getFieldStartOffset()
    {
        return startPlex.getFcStart();
    }

    public CharacterRun getMarkEndCharacterRun( Range parent )
    {
        return new Range( getMarkEndOffset(), getMarkEndOffset() + 1, parent )
                .getCharacterRun( 0 );
    }

    /**
     * @return character position of end field mark
     */
    public int getMarkEndOffset()
    {
        return endPlex.getFcStart();
    }

    public CharacterRun getMarkSeparatorCharacterRun( Range parent )
    {
        if ( !hasSeparator() )
            return null;

        return new Range( getMarkSeparatorOffset(),
                getMarkSeparatorOffset() + 1, parent ).getCharacterRun( 0 );
    }

    /**
     * @return character position of separator field mark (if present,
     *         {@link NullPointerException} otherwise)
     */
    public int getMarkSeparatorOffset()
    {
        return separatorPlex.getFcStart();
    }

    public CharacterRun getMarkStartCharacterRun( Range parent )
    {
        return new Range( getMarkStartOffset(), getMarkStartOffset() + 1,
                parent ).getCharacterRun( 0 );
    }

    /**
     * @return character position of start field mark
     */
    public int getMarkStartOffset()
    {
        return startPlex.getFcStart();
    }

    public int getType()
    {
        return startPlex.getFld().getFieldType();
    }

    public boolean hasSeparator()
    {
        return separatorPlex != null;
    }

    public boolean isHasSep()
    {
        return endPlex.getFld().isFHasSep();
    }

    public boolean isLocked()
    {
        return endPlex.getFld().isFLocked();
    }

    public boolean isNested()
    {
        return endPlex.getFld().isFNested();
    }

    public boolean isPrivateResult()
    {
        return endPlex.getFld().isFPrivateResult();
    }

    public boolean isResultDirty()
    {
        return endPlex.getFld().isFResultDirty();
    }

    public boolean isResultEdited()
    {
        return endPlex.getFld().isFResultEdited();
    }

    public boolean isZombieEmbed()
    {
        return endPlex.getFld().isFZombieEmbed();
    }

    public Range secondSubrange( Range parent )
    {
        if ( !hasSeparator()
                || getMarkSeparatorOffset() + 1 == getMarkEndOffset() )
            return null;

        return new Range( getMarkSeparatorOffset() + 1, getMarkEndOffset(),
                parent )
        {
            @Override
            public String toString()
            {
                return "FieldSubrange2 (" + super.toString() + ")";
            }
        };
    }

    @Override
    public String toString()
    {
        return "Field [" + getFieldStartOffset() + "; " + getFieldEndOffset()
                + "] (type: 0x" + Integer.toHexString( getType() ) + " = "
                + getType() + " )";
    }
}