/*
 * Copyright (c) 2008-2024 Jonathan Schleifer <js@nil.im>
 *
 * All rights reserved.
 *
 * This program is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License version 3.0 only,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
 * version 3.0 for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * version 3.0 along with this program. If not, see
 * <https://www.gnu.org/licenses/>.
 */

#include "config.h"

#import "OFString.h"

#import "common.h"

const OFChar16 OFCodepage850Table[] = {
	0x00C7, 0x00FC, 0x00E9, 0x00E2, 0x00E4, 0x00E0, 0x00E5, 0x00E7,
	0x00EA, 0x00EB, 0x00E8, 0x00EF, 0x00EE, 0x00EC, 0x00C4, 0x00C5,
	0x00C9, 0x00E6, 0x00C6, 0x00F4, 0x00F6, 0x00F2, 0x00FB, 0x00F9,
	0x00FF, 0x00D6, 0x00DC, 0x00F8, 0x00A3, 0x00D8, 0x00D7, 0x0192,
	0x00E1, 0x00ED, 0x00F3, 0x00FA, 0x00F1, 0x00D1, 0x00AA, 0x00BA,
	0x00BF, 0x00AE, 0x00AC, 0x00BD, 0x00BC, 0x00A1, 0x00AB, 0x00BB,
	0x2591, 0x2592, 0x2593, 0x2502, 0x2524, 0x00C1, 0x00C2, 0x00C0,
	0x00A9, 0x2563, 0x2551, 0x2557, 0x255D, 0x00A2, 0x00A5, 0x2510,
	0x2514, 0x2534, 0x252C, 0x251C, 0x2500, 0x253C, 0x00E3, 0x00C3,
	0x255A, 0x2554, 0x2569, 0x2566, 0x2560, 0x2550, 0x256C, 0x00A4,
	0x00F0, 0x00D0, 0x00CA, 0x00CB, 0x00C8, 0x0131, 0x00CD, 0x00CE,
	0x00CF, 0x2518, 0x250C, 0x2588, 0x2584, 0x00A6, 0x00CC, 0x2580,
	0x00D3, 0x00DF, 0x00D4, 0x00D2, 0x00F5, 0x00D5, 0x00B5, 0x00FE,
	0x00DE, 0x00DA, 0x00DB, 0x00D9, 0x00FD, 0x00DD, 0x00AF, 0x00B4,
	0x00AD, 0x00B1, 0x2017, 0x00BE, 0x00B6, 0x00A7, 0x00F7, 0x00B8,
	0x00B0, 0x00A8, 0x00B7, 0x00B9, 0x00B3, 0x00B2, 0x25A0, 0x00A0
};
const size_t OFCodepage850TableOffset =
    256 - (sizeof(OFCodepage850Table) / sizeof(*OFCodepage850Table));


static const unsigned char page0[] = {
	0xFF, 0xAD, 0xBD, 0x9C, 0xCF, 0xBE, 0xDD, 0xF5,
	0xF9, 0xB8, 0xA6, 0xAE, 0xAA, 0xF0, 0xA9, 0xEE,
	0xF8, 0xF1, 0xFD, 0xFC, 0xEF, 0xE6, 0xF4, 0xFA,
	0xF7, 0xFB, 0xA7, 0xAF, 0xAC, 0xAB, 0xF3, 0xA8,
	0xB7, 0xB5, 0xB6, 0xC7, 0x8E, 0x8F, 0x92, 0x80,
	0xD4, 0x90, 0xD2, 0xD3, 0xDE, 0xD6, 0xD7, 0xD8,
	0xD1, 0xA5, 0xE3, 0xE0, 0xE2, 0xE5, 0x99, 0x9E,
	0x9D, 0xEB, 0xE9, 0xEA, 0x9A, 0xED, 0xE8, 0xE1,
	0x85, 0xA0, 0x83, 0xC6, 0x84, 0x86, 0x91, 0x87,
	0x8A, 0x82, 0x88, 0x89, 0x8D, 0xA1, 0x8C, 0x8B,
	0xD0, 0xA4, 0x95, 0xA2, 0x93, 0xE4, 0x94, 0xF6,
	0x9B, 0x97, 0xA3, 0x96, 0x81, 0xEC, 0xE7, 0x98
};
static const uint8_t page0Start = 0xA0;

static const unsigned char page1[] = {
	0xD5, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x9F
};
static const uint8_t page1Start = 0x31;

static const unsigned char page20[] = {
	0xF2
};
static const uint8_t page20Start = 0x17;

static const unsigned char page25[] = {
	0xC4, 0x00, 0xB3, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0xDA, 0x00, 0x00, 0x00,
	0xBF, 0x00, 0x00, 0x00, 0xC0, 0x00, 0x00, 0x00,
	0xD9, 0x00, 0x00, 0x00, 0xC3, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0xB4, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0xC2, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0xC1, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0xC5, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0xCD, 0xBA, 0x00, 0x00, 0xC9, 0x00, 0x00, 0xBB,
	0x00, 0x00, 0xC8, 0x00, 0x00, 0xBC, 0x00, 0x00,
	0xCC, 0x00, 0x00, 0xB9, 0x00, 0x00, 0xCB, 0x00,
	0x00, 0xCA, 0x00, 0x00, 0xCE, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0xDF, 0x00, 0x00, 0x00, 0xDC, 0x00, 0x00, 0x00,
	0xDB, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0xB0, 0xB1, 0xB2, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0xFE
};
static const uint8_t page25Start = 0x00;

bool
OFUnicodeToCodepage850(const OFUnichar *input, unsigned char *output,
    size_t length, bool lossy)
{
	for (size_t i = 0; i < length; i++) {
		OFUnichar c = input[i];

		if OF_UNLIKELY (c > 0x7F) {
			uint8_t idx;

			if OF_UNLIKELY (c > 0xFFFF) {
				if (lossy) {
					output[i] = '?';
					continue;
				} else
					return false;
			}

			switch (c >> 8) {
			CASE_MISSING_IS_ERROR(0)
			CASE_MISSING_IS_ERROR(1)
			CASE_MISSING_IS_ERROR(20)
			CASE_MISSING_IS_ERROR(25)
			default:
				if (lossy) {
					output[i] = '?';
					continue;
				} else
					return false;
			}
		} else
			output[i] = (unsigned char)c;
	}

	return true;
}