package org.litesoft.textfiledirectory;

import org.litesoft.commonfoundation.annotations.*;
import org.litesoft.commonfoundation.base.*;
import org.litesoft.commonfoundation.typeutils.*;
import org.litesoft.core.simpletypes.*;
import org.litesoft.server.file.*;

import java.io.*;

public class TextFileDirectoryFileSystem extends AbstractTextFileDirectory {
    private final File mDirectory;

    public TextFileDirectoryFileSystem( File pDirectory ) {
        mDirectory = Confirm.isNotNull( "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 = Confirm.significant( "FileName", pFileName ) ) );
        return new TextFile( pFileName, zLines );
    }

    @Override
    public void create( @NotNull TextFile pFile )
            throws FileAlreadyExists {
        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( Confirm.significant( "FileName", pFileName ) ) );
    }

    private void write( File pFile, TextFile pTextFile ) {
        Directories.insureParent( 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( Confirm.isNotNull( "File", pFile ).getFileName() );
    }

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