SquirrelJME/SquirrelJME

// -*- Mode: Java; indent-tabs-mode: t; tab-width: 4 -*-
// ---------------------------------------------------------------------------
// Multi-Phasic Applications: SquirrelJME
//     Copyright (C) Stephanie Gawroriski <xer@multiphasicapps.net>
// ---------------------------------------------------------------------------
// SquirrelJME is under the GNU General Public License v3+, or later.
// See license.mkd for licensing and copyright information.
// ---------------------------------------------------------------------------

package cc.squirreljme.runtime.gcf;

import cc.squirreljme.runtime.cldc.debug.Debugging;

/**
 * This class contains HTTP utilities.
 *
 * @since 2022/10/11
 */
public final class HTTPUtils
{
    /**
     * Not used.
     * 
     * @since 2022/10/11
     */
    private HTTPUtils()
    {
    }
    
    /**
     * Decodes the specified string to handle different parts of the URL which
     * may be encoded or not.
     *
     * @param __charSet The character set to use.
     * @param __p The string.
     * @return The decoded string.
     * @throws IllegalArgumentException If the string is not valid.
     * @throws NullPointerException On null arguments.
     * @since 2019/05/06
     */
    public static String stringDecode(HTTPUrlCharacterSet __charSet,
        String __p)
        throws IllegalArgumentException, NullPointerException
    {
        if (__charSet == null || __p == null)
            throw new NullPointerException("NARG");
        
        // Build new decoded path
        StringBuilder sb = new StringBuilder();
        for (int i = 0, n = __p.length(); i < n;)
        {
            int c = __p.charAt(i++);
            
            // Potentially condense slashes, paths only
            if (c == '/' && __charSet == HTTPUrlCharacterSet.PATH)
            {
                // Do not condense
                int sbl = sb.length();
                if (sbl > 0 && sb.charAt(sbl - 1) == '/')
                    continue;
                
                // Add slash
                sb.append('/');
            }
            
            // Percent encoded
            else if (c == '%')
            {
                throw Debugging.todo();
            }
            
            // Directly usable
            else if (__charSet.isValid((char)c))
                sb.append((char)c);
            
            // {@squirreljme.error EC01 String contains invalid character.
            // (The path)}
            else
                throw new IllegalArgumentException("EC01 " + __p);
        }
        
        // Done
        return sb.toString();
    }
}