package org.litesoft.textfiledirectory;

import java.io.*;

import org.litesoft.core.annotations.*;
import org.litesoft.core.simpletypes.*;
import org.litesoft.core.typeutils.*;
import org.litesoft.core.util.*;
import org.litesoft.util.*;

public class TextFileDirectoryFileSystem extends AbstractTextFileDirectory
{
    private final File mDirectory;

    public TextFileDirectoryFileSystem( File pDirectory )
    {
        mDirectory = Objects.assertNotNull( "Directory", pDirectory );
        if ( mDirectory.isFile() )
        {
            throw new IllegalArgumentException( "Directory '" + pDirectory + "' is not a directory, but a file!" );
        }
    }

    @Override
    public String getDirectoryPath()
    {
        return mDirectory.getAbsolutePath();
    }

    @Override
    public boolean exists()
    {
        return mDirectory.isDirectory();
    }

    @Override
    public String[] getFiles( String... pExtensions )
    {
        final String[] zExtensions = preprocessExtensions( pExtensions );
        if ( !mDirectory.isDirectory() )
        {
            return Strings.EMPTY_ARRAY;
        }
        if ( zExtensions.length == 0 )
        {
            return mDirectory.list();
        }
        return mDirectory.list( new FilenameFilter()
        {
            @Override
            public boolean accept( File dir, String name )
            {
                for ( String zExtension : zExtensions )
                {
                    if ( name.endsWith( zExtension ) )
                    {
                        return true;
                    }
                }
                return false;
            }
        } );
    }

    @Override
    public TextFile load( @NotNull String pFileName )
            throws FileDoesNotExists
    {
        String[] zLines = FileUtils.loadTextFile( getFile( pFileName = UtilsCommon.assertNotNullNotEmpty( "FileName", pFileName ) ) );
        return new TextFile( pFileName, zLines );
    }

    @Override
    public void create( @NotNull TextFile pFile )
            throws FileAlreadExists
    {
        write( assertNotExist( getFile( pFile ) ), pFile );
    }

    @Override
    public void update( @NotNull TextFile pFile )
            throws FileDoesNotExists
    {
        write( assertIsFile( getFile( pFile ) ), pFile );
    }

    @Override
    public void delete( @NotNull TextFile pFile )
            throws FileDoesNotExists
    {
        delete( getFile( pFile ) );
    }

    @Override
    public void delete( @NotNull String pFileName )
            throws FileDoesNotExists
    {
        delete( getFile( UtilsCommon.assertNotNullNotEmpty( "FileName", pFileName ) ) );
    }

    private void write( File pFile, TextFile pTextFile )
    {
        DirectoryUtils.insureParentDirectory( pFile );
        FileUtils.storeTextFile( pFile, pTextFile.getLines() );
    }

    private void delete( File pFile )
    {
        FileUtils.deleteIfExists( assertIsFile( pFile ) );
    }

    private File assertIsFile( File pFile )
    {
        assertExists( pFile.isFile(), pFile.getName() );
        return pFile;
    }

    private File assertNotExist( File pFile )
    {
        assertNotExists( pFile.exists(), pFile.getName() );
        return pFile;
    }

    private File getFile( TextFile pFile )
    {
        return getFile( Objects.assertNotNull( "File", pFile ).getFileName() );
    }

    private File getFile( String pFileName )
    {
        return new File( mDirectory, pFileName );
    }
}