/*******************************************************************************

    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2014.

    This file is part of Sortix.

    Sortix 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 (at your option) any later
    version.

    Sortix 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
    Sortix. If not, see <http://www.gnu.org/licenses/>.

    vga.h
    A Video Graphics Array driver.

*******************************************************************************/

#ifndef SORTIX_VGA_H
#define SORTIX_VGA_H

#include <stddef.h>

#include <sortix/kernel/refcount.h>

namespace Sortix {

class Descriptor;

const size_t VGA_FONT_WIDTH = 8UL;
const size_t VGA_FONT_HEIGHT = 16UL;
const size_t VGA_FONT_NUMCHARS = 256UL;
const size_t VGA_FONT_CHARSIZE = VGA_FONT_WIDTH * VGA_FONT_HEIGHT / 8UL;

namespace VGA {

// https://en.wikipedia.org/wiki/Code_page_437
__attribute__((unused))
static inline int MapWideToVGAFont(wchar_t c)
{
	if ( 32 <= c && c < 127 )
		return (int) c;
	switch ( c )
	{
	case L'☺': return 1;
	case L'☻': return 2;
	case L'♥': return 3;
	case L'♦': return 4;
	case L'♣': return 5;
	case L'♠': return 6;
	case L'•': return 7;
	case L'◘': return 8;
	case L'○': return 9;
	case L'◙': return 10;
	case L'♂': return 11;
	case L'♀': return 12;
	case L'♪': return 13;
	case L'♬': return 14;
	case L'☼': return 15;
	case L'►': return 16;
	case L'◄': return 17;
	case L'↕': return 18;
	case L'‼': return 19;
	case L'¶': return 20;
	case L'§': return 21;
	case L'▬': return 22;
	case L'↨': return 23;
	case L'↑': return 24;
	case L'↓': return 25;
	case L'→': return 26;
	case L'←': return 27;
	case L'∟': return 28;
	case L'↔': return 29;
	case L'▲': return 30;
	case L'▼': return 31;
	case L'⌂': return 127;
	case L'Ç': return 128;
	case L'ü': return 129;
	case L'é': return 130;
	case L'â': return 131;
	case L'ä': return 132;
	case L'à': return 133;
	case L'å': return 134;
	case L'ç': return 135;
	case L'ê': return 136;
	case L'ë': return 137;
	case L'è': return 138;
	case L'ï': return 139;
	case L'î': return 140;
	case L'ì': return 141;
	case L'Ä': return 142;
	case L'Å': return 143;
	case L'É': return 144;
	case L'æ': return 145;
	case L'Æ': return 146;
	case L'ô': return 147;
	case L'ö': return 148;
	case L'ò': return 149;
	case L'û': return 150;
	case L'ù': return 151;
	case L'ÿ': return 152;
	case L'Ö': return 153;
	case L'Ü': return 154;
	case L'¢': return 155;
	case L'£': return 156;
	case L'¥': return 157;
	case L'₧': return 158;
	case L'ƒ': return 159;
	case L'á': return 160;
	case L'í': return 161;
	case L'ó': return 162;
	case L'ú': return 163;
	case L'ñ': return 164;
	case L'Ñ': return 165;
	case L'ª': return 166;
	case L'º': return 167;
	case L'¿': return 168;
	case L'⌐': return 169;
	case L'¬': return 170;
	case L'½': return 171;
	case L'¼': return 172;
	case L'¡': return 173;
	case L'«': return 174;
	case L'»': return 175;
	case L'░': return 176;
	case L'▒': return 177;
	case L'▓': return 178;
	case L'│': return 179;
	case L'┤': return 180;
	case L'╡': return 181;
	case L'╢': return 182;
	case L'╖': return 183;
	case L'╕': return 184;
	case L'╣': return 185;
	case L'║': return 186;
	case L'╗': return 187;
	case L'╝': return 188;
	case L'╜': return 189;
	case L'╛': return 190;
	case L'┐': return 191;
	case L'└': return 192;
	case L'┴': return 193;
	case L'┬': return 194;
	case L'├': return 195;
	case L'─': return 196;
	case L'┼': return 197;
	case L'╞': return 198;
	case L'╟': return 199;
	case L'╚': return 200;
	case L'╔': return 201;
	case L'╩': return 202;
	case L'╦': return 203;
	case L'╠': return 204;
	case L'═': return 205;
	case L'╬': return 206;
	case L'╧': return 207;
	case L'╨': return 208;
	case L'╤': return 209;
	case L'╥': return 210;
	case L'╙': return 211;
	case L'╘': return 212;
	case L'╒': return 213;
	case L'╓': return 214;
	case L'╫': return 215;
	case L'╪': return 216;
	case L'┘': return 217;
	case L'┌': return 218;
	case L'█': return 219;
	case L'▄': return 220;
	case L'▌': return 221;
	case L'▐': return 222;
	case L'▀': return 223;
	case L'α': return 224;
	case L'ß': return 225; /* German sharp S U+00DF */
	case L'β': return 225; /* Greek lowercase beta U+03B2 */
	case L'Γ': return 226;
	case L'π': return 227;
	case L'Σ': return 228; /* Greek uppercase sigma U+03A3 */
	case L'∑': return 228; /* n-ary summation sign U+2211 (replacement) */
	case L'σ': return 229;
	case L'µ': return 230;
	case L'τ': return 231;
	case L'Φ': return 232;
	case L'Θ': return 233;
	case L'Ω': return 234;
	case L'δ': return 235; /* Greek lowercase delta U+03B4 */
	case L'ð': return 235; /* Icelandic lowercase eth U+00F0 (replacement) */
	case L'∂': return 235; /* Partial derivative sign U+2202 (replacement) */
	case L'∞': return 236;
	case L'φ': return 237; /* Greek lowercase phi U+03C6 */
	case L'∅': return 237; /* Empty set sign U+2205 (replacement) */
	case L'ϕ': return 237; /* Greek phi symbol in italics U+03D5 (replacement) */
	case L'⌀': return 237; /* Diameter sign U+2300 (replacement) */
	case L'ø': return 237; /* Latin lowercase O with stroke U+00F8 (replacement) */
	case L'Ø': return 237; /* Latin uppercase O with stroke U+00D8 (replacement) */
	case L'ε': return 238; /* Greek lowercase epsilon U+03B5 */
	case L'∈': return 238; /* Element-of sign U+2208 */
	case L'€': return 238; /* Euro sign U+20AC */
	case L'∩': return 239;
	case L'≡': return 240;
	case L'±': return 241;
	case L'≥': return 242;
	case L'≤': return 243;
	case L'⌠': return 244;
	case L'⌡': return 245;
	case L'÷': return 246;
	case L'≈': return 247;
	case L'°': return 248;
	case L'∙': return 249;
	case L'·': return 250;
	case L'√': return 251;
	case L'ⁿ': return 252;
	case L'²': return 253;
	case L'■': return 254;
	default: return 0 <= c && c < 256 ? c : -1;
	}
}

__attribute__((unused))
static const uint8_t font_replacement_character[16] =
{
	0b00000000,
	0b00010000,
	0b00111000,
	0b01000100,
	0b10111010,
	0b10111010,
	0b11110110,
	0b11101110,
	0b11101110,
	0b11111110,
	0b01101100,
	0b00101000,
	0b00010000,
	0b00000000,
	0b00000000,
	0b00000000,
};

__attribute__((unused))
static inline const uint8_t* GetCharacterFont(const uint8_t* font, wchar_t wc)
{
	if ( wc == L'�' )
		return font_replacement_character;
	int remap = MapWideToVGAFont(wc);
	if ( remap < 0 )
		return font_replacement_character;
	return font + 16 * remap;
}

void Init(const char* devpath, Ref<Descriptor> slashdev);
void SetCursor(unsigned x, unsigned y);
const uint8_t* GetFont();

} // namespace VGA

} // namespace Sortix

#endif