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 net.multiphasicapps.pcftosqf.pcf;

import java.io.DataInputStream;
import java.io.IOException;
import java.lang.ref.Reference;
import java.lang.ref.WeakReference;

/**
 * This contains a single metric within a PCF file.
 *
 * @since 2018/11/27
 */
public final class PCFMetric
{
    /** Compressed metrics format. */
    static final int _PCF_COMPRESSED_METRICS =
        0x00000100;
    
    /** Left side bearing. */
    public final short leftsidebearing;
    
    /** Right side bearing. */
    public final short rightsidebearing;
    
    /** Character width. */
    public final short charwidth;
    
    /** Character ascent. */
    public final short charascent;
    
    /** Character descent. */
    public final short chardescent;
    
    /** Character attributes. */
    public final int attributes;
    
    /** String representation. */
    private Reference<String> _string;
    
    /**
     * Initializes the metric.
     *
     * @param __lsb Left side bearing.
     * @param __rsb Right side bearing.
     * @param __cw Character width.
     * @param __ca Character ascent.
     * @param __cd Character descent.
     * @param __a Attributes.
     * @since 2018/11/27
     */
    PCFMetric(short __lsb, short __rsb, short __cw, short __ca,
        short __cd, int __a)
    {
        this.leftsidebearing = __lsb;
        this.rightsidebearing = __rsb;
        this.charwidth = __cw;
        this.charascent = __ca;
        this.chardescent = __cd;
        this.attributes = __a;
    }
    
    /**
     * {@inheritDoc}
     * @since 2018/11/27
     */
    @Override
    public final String toString()
    {
        Reference<String> ref = this._string;
        String rv;
        
        if (ref == null || null == (rv = ref.get()))
            this._string = new WeakReference<>((rv = String.format(
                "{leftsidebearing=%d, rightsidebearing=%d, " +
                "charwidth=%d, charascent=%d, chardescent=%d, " +
                "attributes=%x}", this.leftsidebearing,
                this.rightsidebearing, this.charwidth, this.charascent,
                this.chardescent, this.attributes)));
        
        return rv;
    }
    
    /**
     * Reads a compressed metric from the input.
     *
     * @param __dis The stream to read from.
     * @return The metric.
     * @throws IOException On read errors.
     * @throws NullPointerException On null arguments.
     * @since 2018/11/27
     */
    public static final PCFMetric readCompressed(DataInputStream __dis)
        throws IOException, NullPointerException
    {
        if (__dis == null)
            throw new NullPointerException("NARG");
        
        // All are unsigned bytes with implied attributes of zero
        // All of the values are offset signed
        return new PCFMetric(
            (short)(__dis.readUnsignedByte() - 0x80),
            (short)(__dis.readUnsignedByte() - 0x80),
            (short)(__dis.readUnsignedByte() - 0x80),
            (short)(__dis.readUnsignedByte() - 0x80),
            (short)(__dis.readUnsignedByte() - 0x80),
            0);
    }
    
    /**
     * Reads the metric table.
     *
     * @param __dis The stream to read from.
     * @return The read metrics.
     * @throws IOException On read errors.
     * @throws NullPointerException On null arguments.
     * @since 2018/11/27
     */
    public static final PCFMetric[] readMetrics(DataInputStream __dis)
        throws IOException, NullPointerException
    {
        if (__dis == null)
            throw new NullPointerException("NARG");
        
        PCFMetric[] rv;
        
        // Are these compressed metrics
        if (((Integer.reverseBytes(__dis.readInt())) & PCFMetric._PCF_COMPRESSED_METRICS) != 0)
        {
            // Read length
            int n = __dis.readUnsignedShort();
            rv = new PCFMetric[n];
            
            // Read all metrics            
            for (int i = 0; i < n; i++)
                rv[i] = PCFMetric.readCompressed(__dis);
        }
        
        // They are uncompressed
        else
        {
            // Read length
            int n = __dis.readInt();
            rv = new PCFMetric[n];
            
            // Read all metrics            
            for (int i = 0; i < n; i++)
                rv[i] = PCFMetric.readUncompressed(__dis);
        }
        
        return rv;
    }
    
    /**
     * Reads an uncompressed metric from the input.
     *
     * @param __dis The stream to read from.
     * @return The metric.
     * @throws IOException On read errors.
     * @throws NullPointerException On null arguments.
     * @since 2018/11/27
     */
    public static final PCFMetric readUncompressed(DataInputStream __dis)
        throws IOException, NullPointerException
    {
        if (__dis == null)
            throw new NullPointerException("NARG");
        
        // All are unsigned bytes with implied attributes of zero
        return new PCFMetric(
            __dis.readShort(),
            __dis.readShort(),
            __dis.readShort(),
            __dis.readShort(),
            __dis.readShort(),
            __dis.readUnsignedShort());
    }
}