/*
 * "Software pw3270, desenvolvido com base nos códigos fontes do WC3270  e X3270
 * (Paul Mattes Paul.Mattes@usa.net), de emulação de terminal 3270 para acesso a
 * aplicativos mainframe. Registro no INPI sob o nome G3270. Registro no INPI sob o nome G3270.
 *
 * Copyright (C) <2008> <Banco do Brasil S.A.>
 *
 * Este programa é software livre. Você pode redistribuí-lo e/ou modificá-lo sob
 * os termos da GPL v.2 - Licença Pública Geral  GNU,  conforme  publicado  pela
 * Free Software Foundation.
 *
 * Este programa é distribuído na expectativa de  ser  útil,  mas  SEM  QUALQUER
 * GARANTIA; sem mesmo a garantia implícita de COMERCIALIZAÇÃO ou  de  ADEQUAÇÃO
 * A QUALQUER PROPÓSITO EM PARTICULAR. Consulte a Licença Pública Geral GNU para
 * obter mais detalhes.
 *
 * Você deve ter recebido uma cópia da Licença Pública Geral GNU junto com este
 * programa; se não, escreva para a Free Software Foundation, Inc., 51 Franklin
 * St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Este programa está nomeado como charset.c e possui - linhas de código.
 *
 * Contatos:
 *
 * perry.werneck@gmail.com	(Alexandre Perry de Souza Werneck)
 * erico.mendonca@gmail.com	(Erico Mascarenhas Mendonça)
 * licinio@bb.com.br		(Licínio Luis Branco)
 * kraucer@bb.com.br		(Kraucer Fernandes Mazuco)
 *
 */

/**
 *	@file charset.c
 *
 *	@brief This module handles character sets.
 */

#include <internals.h>
#include <X11keysym.h>
#include <lib3270/charset.h>
#include <lib3270/log.h>
#include <lib3270/trace.h>

/*
 * EBCDIC-to-Unicode translation tables.
 * Each table maps EBCDIC codes X'41' through X'FE' to UCS-2.
 * Other codes are mapped programmatically.
 */
#define UT_SIZE		190
#define UT_OFFSET	0x41

/*---[ Statics ]--------------------------------------------------------------------------------------------------------------*/

const unsigned short ebc2asc0[256] = {
	/*00*/	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
	/*08*/	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
	/*10*/	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
	/*18*/	0x20, 0x20, 0x20, 0x20, 0x2a, 0x20, 0x3b, 0x20,
	/*20*/	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
	/*28*/	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
	/*30*/	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
	/*38*/	0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
	/*40*/	0x20, 0x20, 0xe2, 0xe4, 0xe0, 0xe1, 0xe3, 0xe5,
	/*48*/	0xe7, 0xf1, 0xa2, 0x2e, 0x3c, 0x28, 0x2b, 0x7c,
	/*50*/	0x26, 0xe9, 0xea, 0xeb, 0xe8, 0xed, 0xee, 0xef,
	/*58*/	0xec, 0xdf, 0x21, 0x24, 0x2a, 0x29, 0x3b, 0xac,
	/*60*/	0x2d, 0x2f, 0xc2, 0xc4, 0xc0, 0xc1, 0xc3, 0xc5,
	/*68*/	0xc7, 0xd1, 0xa6, 0x2c, 0x25, 0x5f, 0x3e, 0x3f,
	/*70*/	0xf8, 0xc9, 0xca, 0xcb, 0xc8, 0xcd, 0xce, 0xcf,
	/*78*/	0xcc, 0x60, 0x3a, 0x23, 0x40, 0x27, 0x3d, 0x22,
	/*80*/	0xd8, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
	/*88*/	0x68, 0x69, 0xab, 0xbb, 0xf0, 0xfd, 0xfe, 0xb1,
	/*90*/	0xb0, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70,
	/*98*/	0x71, 0x72, 0xaa, 0xba, 0xe6, 0xb8, 0xc6, 0xa4,
	/*a0*/	0xb5, 0x7e, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
	/*a8*/	0x79, 0x7a, 0xa1, 0xbf, 0xd0, 0xdd, 0xde, 0xae,
	/*b0*/	0x5e, 0xa3, 0xa5, 0xb7, 0xa9, 0xa7, 0xb6, 0xbc,
	/*b8*/	0xbd, 0xbe, 0x5b, 0x5d, 0xaf, 0xa8, 0xb4, 0xd7,
	/*c0*/	0x7b, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
	/*c8*/	0x48, 0x49, 0xad, 0xf4, 0xf6, 0xf2, 0xf3, 0xf5,
	/*d0*/	0x7d, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 0x50,
	/*d8*/	0x51, 0x52, 0xb9, 0xfb, 0xfc, 0xf9, 0xfa, 0xff,
	/*e0*/	0x5c, 0xf7, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
	/*e8*/	0x59, 0x5a, 0xb2, 0xd4, 0xd6, 0xd2, 0xd3, 0xd5,
	/*f0*/	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
	/*f8*/	0x38, 0x39, 0xb3, 0xdb, 0xdc, 0xd9, 0xda, 0x20
};

static const unsigned short asc2ebc0[256] = {
	/*00*/  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	/*08*/  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	/*10*/  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	/*18*/  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	/*20*/  0x40, 0x5a, 0x7f, 0x7b, 0x5b, 0x6c, 0x50, 0x7d,
	/*28*/  0x4d, 0x5d, 0x5c, 0x4e, 0x6b, 0x60, 0x4b, 0x61,
	/*30*/  0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,
	/*38*/  0xf8, 0xf9, 0x7a, 0x5e, 0x4c, 0x7e, 0x6e, 0x6f,
	/*40*/  0x7c, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
	/*48*/  0xc8, 0xc9, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6,
	/*50*/  0xd7, 0xd8, 0xd9, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6,
	/*58*/  0xe7, 0xe8, 0xe9, 0xba, 0xe0, 0xbb, 0xb0, 0x6d,
	/*60*/  0x79, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
	/*68*/  0x88, 0x89, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96,
	/*70*/  0x97, 0x98, 0x99, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6,
	/*78*/  0xa7, 0xa8, 0xa9, 0xc0, 0x4f, 0xd0, 0xa1, 0x00,
	/*80*/  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	/*88*/  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	/*90*/  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	/*98*/  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	/*a0*/  0x41, 0xaa, 0x4a, 0xb1, 0x9f, 0xb2, 0x6a, 0xb5,
	/*a8*/  0xbd, 0xb4, 0x9a, 0x8a, 0x5f, 0xca, 0xaf, 0xbc,
	/*b0*/  0x90, 0x8f, 0xea, 0xfa, 0xbe, 0xa0, 0xb6, 0xb3,
	/*b8*/  0x9d, 0xda, 0x9b, 0x8b, 0xb7, 0xb8, 0xb9, 0xab,
	/*c0*/  0x64, 0x65, 0x62, 0x66, 0x63, 0x67, 0x9e, 0x68,
	/*c8*/  0x74, 0x71, 0x72, 0x73, 0x78, 0x75, 0x76, 0x77,
	/*d0*/  0xac, 0x69, 0xed, 0xee, 0xeb, 0xef, 0xec, 0xbf,
	/*d8*/  0x80, 0xfd, 0xfe, 0xfb, 0xfc, 0xad, 0xae, 0x59,
	/*e0*/  0x44, 0x45, 0x42, 0x46, 0x43, 0x47, 0x9c, 0x48,
	/*e8*/  0x54, 0x51, 0x52, 0x53, 0x58, 0x55, 0x56, 0x57,
	/*f0*/  0x8c, 0x49, 0xcd, 0xce, 0xcb, 0xcf, 0xcc, 0xe1,
	/*f8*/  0x70, 0xdd, 0xde, 0xdb, 0xdc, 0x8d, 0x8e, 0xdf
};

static const unsigned short asc2uc[UT_SIZE] = {
	/*40*/	      0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
	/*48*/	0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
	/*50*/	0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
	/*58*/	0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
	/*60*/	0x60, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
	/*68*/	0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
	/*70*/	0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
	/*78*/	0x58, 0x59, 0x5a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
	/*80*/	0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
	/*88*/	0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
	/*90*/	0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
	/*98*/	0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
	/*a0*/	0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
	/*a8*/	0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
	/*b0*/	0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7,
	/*b8*/	0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
	/*c0*/	0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
	/*c8*/	0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
	/*d0*/	0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,
	/*d8*/	0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,
	/*e0*/	0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
	/*e8*/	0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
	/*f0*/	0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xf7,
	/*f8*/	0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde
};

typedef struct _info {
	const char				* name;
	unsigned long			  cgcsgid;
	const unsigned short	* chr;
} remap;

static const remap charset[] = {
	{
		"us",
		LIB3270_DEFAULT_CGEN | LIB3270_DEFAULT_CSET,
		(const unsigned short []) {
			0x0000,	0x0000
		}
	},

	{
		"bracket",
		LIB3270_DEFAULT_CGEN|LIB3270_DEFAULT_CSET,
		(const unsigned short []) {
			0x00ad, '[',
			0x00ba, XK_Yacute,
			0x00bd, ']',
			0x00bb, XK_diaeresis,
			0x0000,	0x0000
		}
	},

	{
		"cp500",
		LIB3270_DEFAULT_CGEN|0x000001F4,
		(const unsigned short []) {
			0x004a, '[',
			0x004f, '!',
			0x005a, ']',
			0x005f, '^',
			0x00b0, XK_percent,
			0x00ba, XK_notsign,
			0x00bb, XK_bar
		}
	},

	// Terminate list
	{
		NULL
	}

};

/*---[ Implement ]------------------------------------------------------------------------------------------------------------*/

static void copy_charset(const unsigned short *from, unsigned short *to) {
	int f;
	for(f=0; f < UT_SIZE; f++)
		to[f+UT_OFFSET] = from[f];
}

LIB3270_EXPORT void lib3270_reset_charset(H3270 *hSession, const char * host, const char * display, unsigned long cgcsgid) {
	int f;

#define replace_pointer(x,v) if(x) { lib3270_free(x); }; x = strdup(v)

	if(!host)
		host = "us";

	if(!display)
		display = "ISO-8859-1";

	debug("%s(%s,%s)",__FUNCTION__,host,display);

	replace_pointer(hSession->charset.host, host);
	replace_pointer(hSession->charset.display,display);

	hSession->charset.cgcsgid = cgcsgid;

	memcpy(hSession->charset.ebc2asc,	ebc2asc0,	sizeof(hSession->charset.ebc2asc));
	memcpy(hSession->charset.asc2ebc,	asc2ebc0,	sizeof(hSession->charset.asc2ebc));

	for(f=0; f<UT_OFFSET; f++)
		hSession->charset.asc2uc[f] = f;

	copy_charset(asc2uc,hSession->charset.asc2uc);

}

LIB3270_EXPORT int lib3270_set_host_charset(H3270 *hSession, const char *name) {
	int f;

	debug("%s(%s)",__FUNCTION__,name);

	if(name && hSession->charset.host && !strcasecmp(name,hSession->charset.host)) {
		debug("Charset is \"%s\", returning",hSession->charset.host);
		return 0;
	}

	if(!name) {
		name = hSession->charset.host;
		debug("Resetting to charset \"%s\"",name);
	}

	if(!name) {
		lib3270_reset_charset(hSession, NULL, NULL, LIB3270_DEFAULT_CGEN | LIB3270_DEFAULT_CSET);
		return 0;
	}

	for(f=0; charset[f].name != NULL; f++) {
		if(!strcasecmp(name,charset[f].name)) {
			// Found required charset
			int c;

			debug("%s: %s -> %s",__FUNCTION__,hSession->charset.host,charset[f].name);

			lib3270_reset_charset(hSession,charset[f].name,"ISO-8859-1", charset[f].cgcsgid);

			for(c=0; charset[f].chr[c]; c+=2)
				lib3270_remap_char(hSession,charset[f].chr[c],charset[f].chr[c+1], BOTH, 0);

			debug("Charset is now \"%s\"",charset[f].name);
			return 0;
		}
	}

	debug("%s: %s",__FUNCTION__,strerror(EINVAL));
	return errno = EINVAL;

}

LIB3270_EXPORT const char * lib3270_get_host_charset(const H3270 *hSession) {
	return hSession->charset.host;
}