SquirrelJME/SquirrelJME

// -*- Mode: Java; indent-tabs-mode: t; tab-width: 4 -*-
// ---------------------------------------------------------------------------
// SquirrelJME
//     Copyright (C) Stephanie Gawroriski <xer@multiphasicapps.net>
// ---------------------------------------------------------------------------
// SquirrelJME is under the Mozilla Public License Version 2.0.
// See license.mkd for licensing and copyright information.
// ---------------------------------------------------------------------------

package cc.squirreljme.vm;

import cc.squirreljme.jvm.launch.ApplicationParser;
import cc.squirreljme.runtime.cldc.debug.Debugging;
import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.StandardOpenOption;

/**
 * Represents a plain data container for detected types which are not JARs or
 * SQCs.
 *
 * @since 2021/06/13
 */
public class DataContainerLibrary
    implements RawVMClassLibrary
{
    /** Data resource name. */
    public static final String RESOURCE_NAME =
        ApplicationParser.DATA_RESOURCE;
    
    /** The path to the ROM. */
    protected final Path path;
    
    /**
     * Initializes the ROM library.
     * 
     * @param __path The ROM path.
     * @throws NullPointerException On null arguments.
     * @since 2021/06/13
     */
    public DataContainerLibrary(Path __path)
        throws NullPointerException
    {
        if (__path == null)
            throw new NullPointerException("NARG");
        
        this.path = __path;
    }
    
    /**
     * Opens a stream to the contained data.
     * 
     * @return The stream to the data.
     * @throws IOException If it could not be opened.
     * @since 2021/09/04
     */
    public final InputStream asStream()
        throws IOException
    {
        return this.resourceAsStream(DataContainerLibrary.RESOURCE_NAME);
    }
    
    /**
     * {@inheritDoc}
     * @since 2021/06/13
     */
    @Override
    public String[] listResources()
    {
        // There is only ever a single resource
        return new String[]{DataContainerLibrary.RESOURCE_NAME};
    }
    
    /**
     * {@inheritDoc}
     * @since 2021/06/13
     */
    @Override
    public String name()
    {
        return this.path.getFileName().toString();
    }
    
    /**
     * {@inheritDoc}
     * @since 2021/06/13
     */
    @Override
    public Path path()
    {
        return this.path;
    }
    
    /**
     * {@inheritDoc}
     * @since 2023/12/30
     */
    @Override
    public void rawData(int __jarOffset, byte[] __b, int __o, int __l)
        throws IllegalStateException, IndexOutOfBoundsException,
        NullPointerException
    {
        if (__b == null)
            throw new NullPointerException("NARG");
        
        // Check that the size is correct.
        int bufLen = __b.length;
        int libLen = this.rawSize();
        if (__jarOffset < 0 || (__jarOffset + __l) < 0 ||
            (__jarOffset + __l) > libLen || __o < 0 || __l < 0 ||
            (__o + __l) < 0 || (__o + __l) > bufLen)
            throw new IndexOutOfBoundsException("IOOB");
        
        // Seek through and find the data
        try (InputStream in = Files.newInputStream(this.path,
            StandardOpenOption.READ))
        {
            // Seek first, stop if EOF is hit
            for (int at = 0; at < __jarOffset; at++)
                if (in.read() < 0)
                    throw new IllegalStateException("FEOF");
            
            // Do a standard read here
            if (in.read(__b, __o, __l) != __l)
                throw new IllegalStateException("SHRT");
        }
        catch (IOException __e)
        {
            throw new IllegalStateException(__e);
        }
    }
    
    /**
     * {@inheritDoc}
     * @since 2023/12/30
     */
    @Override
    public int rawSize()
        throws IllegalStateException
    {
        try
        {
            return (int)Math.min(Integer.MAX_VALUE, Files.size(this.path));
        }
        catch (IOException __e)
        {
            throw new IllegalStateException(__e);
        }
    }
    
    /**
     * {@inheritDoc}
     * @since 2021/06/13
     */
    @Override
    public InputStream resourceAsStream(String __rc)
        throws IOException, NullPointerException
    {
        if (__rc == null)
            throw new NullPointerException("NARG");
        
        // Not our data?
        if (!DataContainerLibrary.RESOURCE_NAME.equals(__rc))
            return null;
        
        return Files.newInputStream(this.path, StandardOpenOption.READ);
    }
    
    /**
     * {@inheritDoc}
     * @since 2021/06/13
     */
    @Override
    public final String toString()
    {
        return this.path.toString();
    }
}