/*
 *  This file is part of uIRC. (https://git.redxen.eu/caskd/uIRC)
 *  Copyright (c) 2019-2021 Alex-David Denes
 *
 *  uIRC is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  any later version.
 *
 *  uIRC 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with uIRC.  If not, see <https://www.gnu.org/licenses/>.
 */

#include "modes.h"

#include <assert.h>   // assert()
#include <ctype.h>    // isalpha()
#include <inttypes.h> // int_least8_t
#include <stddef.h>   //ptrdiff_t

#if ('b' - 'a' != 1 || 'B' - 'A' != 1 || 'z' - 'a' != 25)
#error "System is not US-ASCII." // This is crucial for the conversions below
#endif

static int_least8_t
uirc_mode_index(char mode)
{
	assert(mode != NULL);
	int_least8_t index = 0;
	if (islower(mode)) {
		index += mode - 'a';
	} else if (isupper(mode)) {
		index += ('z' - 'a'); // We offset the index by the size of the lower characters
		index += mode - 'A';
	} else
		return -1;
	return index;
}

bool
uirc_mode_toggle(char m, IRC_Modes ms)
{
	int_least8_t i = uirc_mode_index(m);
	if (i < 0) return false;
	ms[i] = !ms[i];
	return true;
}

bool
uirc_mode_enable(char m, IRC_Modes ms)
{
	int_least8_t i = uirc_mode_index(m);
	if (i < 0) return false;
	ms[i] = true;
	return true;
}

bool
uirc_mode_disable(char m, IRC_Modes ms)
{
	int_least8_t i = uirc_mode_index(m);
	if (i < 0) return false;
	ms[i] = false;
	return true;
}

void
uirc_mode_copy(IRC_Modes d, IRC_Modes const s)
{
	for (unsigned long i = 0; i < sizeof(IRC_Modes) / sizeof(*s); i++) d[i] = s[i];
}

bool
uirc_mode_fetch(char m, IRC_Modes ms)
{
	int_least8_t i = uirc_mode_index(m);
	assert(i != -1);
	return ms[i];
}

const char*
uirc_mode_bmconv(IRC_Modes ms)
{
	static char    bitmask[4];
	unsigned short i = sizeof(bitmask) - 1;
	bitmask[i--]     = '\0';
	bitmask[i--]     = '0';
	bitmask[i--]     = (uirc_mode_fetch(IRC_MODE_WALLOPS, ms)) ? '1' : '0';
	bitmask[i--]     = (uirc_mode_fetch(IRC_MODE_INVISIBLE, ms)) ? '1' : '0';
	return bitmask;
}