#include "../../../line-ed/tty.h"

#include <stdio.h>
#include <string.h>
#include <Windows.h>
#include <io.h>

#define ANSI_BOLD_ON          "1"
#define ANSI_BOLD_OFF         "22"
#define ANSI_ITALIC_ON        "3"
#define ANSI_ITALIC_OFF       "23"
#define ANSI_UNDERLINE_ON     "4"
#define ANSI_UNDERLINE_OFF    "24"

#define ANSI_DEFAULTCOLOUR_FG "39"
#define ANSI_DEFAULTCOLOUR_BG "49"

#define ANSI_256COLOUR_FG     "38;5"
#define ANSI_256COLOUR_BG     "48;5"

#define ANSI_TRUECOLOUR_FG    "38;2"
#define ANSI_TRUECOLOUR_BG    "48;2"

enum tty_flags {
	TTY_INIT = 0x01u,
	TTY_INTERACTIVE = 0x02u,
};

struct s_tty {
	HANDLE t_in, t_out;
	DWORD t_canon_mode_in, t_canon_mode_out;
	enum s_key_code t_repeat_key;
	unsigned int t_repeat_count;
	enum tty_flags t_flags;
	struct s_tty_vmode t_vmode;
	unsigned char t_mcount;
};

static struct s_tty tty = {0};

static WORD ansi_colour16_fg[] = {
	[TTY_COLOUR16_BLACK] = 0,
	[TTY_COLOUR16_RED] = FOREGROUND_RED,
	[TTY_COLOUR16_GREEN] = FOREGROUND_GREEN,
	[TTY_COLOUR16_YELLOW] = FOREGROUND_RED | FOREGROUND_GREEN,
	[TTY_COLOUR16_BLUE] = FOREGROUND_BLUE,
	[TTY_COLOUR16_MAGENTA] = FOREGROUND_RED | FOREGROUND_BLUE,
	[TTY_COLOUR16_CYAN] = FOREGROUND_GREEN | FOREGROUND_BLUE,
	[TTY_COLOUR16_WHITE] = FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE,
	[TTY_COLOUR16_GREY] = FOREGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_RED] = FOREGROUND_RED | FOREGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_GREEN] = FOREGROUND_GREEN | FOREGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_YELLOW] = FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_BLUE] = FOREGROUND_BLUE | FOREGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_MAGENTA] = FOREGROUND_RED | FOREGROUND_BLUE | FOREGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_CYAN] = FOREGROUND_GREEN | FOREGROUND_BLUE | FOREGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_WHITE] = FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE | FOREGROUND_INTENSITY,
};

static WORD ansi_colour16_bg[] = {
	[TTY_COLOUR16_BLACK] = 0,
	[TTY_COLOUR16_RED] = BACKGROUND_RED,
	[TTY_COLOUR16_GREEN] = BACKGROUND_GREEN,
	[TTY_COLOUR16_YELLOW] = BACKGROUND_RED | BACKGROUND_GREEN,
	[TTY_COLOUR16_BLUE] = BACKGROUND_BLUE,
	[TTY_COLOUR16_MAGENTA] = BACKGROUND_RED | BACKGROUND_BLUE,
	[TTY_COLOUR16_CYAN] = BACKGROUND_GREEN | BACKGROUND_BLUE,
	[TTY_COLOUR16_WHITE] = BACKGROUND_RED | BACKGROUND_GREEN | BACKGROUND_BLUE,
	[TTY_COLOUR16_GREY] = BACKGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_RED] = BACKGROUND_RED | BACKGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_GREEN] = BACKGROUND_GREEN | BACKGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_YELLOW] = BACKGROUND_RED | BACKGROUND_GREEN | BACKGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_BLUE] = BACKGROUND_BLUE | BACKGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_MAGENTA] = BACKGROUND_RED | BACKGROUND_BLUE | BACKGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_CYAN] = BACKGROUND_GREEN | BACKGROUND_BLUE | BACKGROUND_INTENSITY,
	[TTY_COLOUR16_BRIGHT_WHITE] = BACKGROUND_RED | BACKGROUND_GREEN | BACKGROUND_BLUE | BACKGROUND_INTENSITY,
};

static void init_tty(struct s_tty *tty, FILE *in, FILE *out)
{
	HANDLE in_handle = (HANDLE)_get_osfhandle(fileno(in));
	HANDLE out_handle = (HANDLE)_get_osfhandle(fileno(out));

	tty->t_in = in_handle;
	tty->t_out = out_handle;
	tty->t_flags |= TTY_INIT;

	DWORD mode = 0;
	if (GetConsoleMode(in_handle, &mode)) {
		tty->t_flags |= TTY_INTERACTIVE;
		tty->t_canon_mode_in = mode;
	}

	if (GetConsoleMode(out_handle, &mode)) {
		tty->t_canon_mode_out = mode;
	}
}

struct s_tty *s_get_tty(void)
{
	if (!(tty.t_flags & TTY_INIT)) {
		init_tty(&tty, stdin, stdout);
	}

	return &tty;
}

bool s_tty_is_interactive(const struct s_tty *tty)
{
	return (tty->t_flags & TTY_INTERACTIVE) == TTY_INTERACTIVE;
}

void s_tty_set_raw(struct s_tty *tty)
{
	DWORD mode = tty->t_canon_mode_in;
	mode &= ~(ENABLE_ECHO_INPUT | ENABLE_INSERT_MODE | ENABLE_LINE_INPUT | ENABLE_QUICK_EDIT_MODE | ENABLE_WINDOW_INPUT);
	mode |= (ENABLE_PROCESSED_INPUT);
	SetConsoleMode(tty->t_in, mode);

	mode = tty->t_canon_mode_out;
	//mode &= ~(ENABLE_PROCESSED_OUTPUT);
	SetConsoleMode(tty->t_out, mode);
}

void s_tty_set_canon(struct s_tty *tty)
{
	SetConsoleMode(tty->t_in, tty->t_canon_mode_in);
	SetConsoleMode(tty->t_out, tty->t_canon_mode_out);
}

void s_tty_reset_vmode(struct s_tty *tty)
{
	if (tty->t_vmode.v_fg.c_mode == TTY_COLOUR_NONE
	    && tty->t_vmode.v_bg.c_mode == TTY_COLOUR_NONE
	    && tty->t_vmode.v_attrib == TTY_ATTRIB_NORMAL) {
		return;
	}

	WORD attrib = FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE;
	SetConsoleTextAttribute(tty->t_out, attrib);

	memset(&tty->t_vmode, 0x0, sizeof tty->t_vmode);

	tty->t_vmode.v_fg.c_mode = TTY_COLOUR_NONE;
	tty->t_vmode.v_bg.c_mode = TTY_COLOUR_NONE;
	tty->t_vmode.v_attrib = TTY_ATTRIB_NORMAL;
}

static int compare_colour(
	const struct s_tty_colour *a, const struct s_tty_colour *b)
{
	if (a->c_mode != b->c_mode) {
		return -1;
	}

	switch (a->c_mode) {
	case TTY_COLOUR_16:
		if (a->c_16.value != b->c_16.value) {
			return -1;
		}
		break;
	case TTY_COLOUR_256:
		if (a->c_256.value != b->c_256.value) {
			return -1;
		}
		break;
	case TTY_COLOUR_TRUE:
		if (a->c_true.r != b->c_true.r) {
			return -1;
		}

		if (a->c_true.g != b->c_true.g) {
			return -1;
		}

		if (a->c_true.b != b->c_true.b) {
			return -1;
		}
		break;
	default:
		break;
	}

	return 0;
}

static int compare_vmode(const struct s_tty_vmode *a, const struct s_tty_vmode *b)
{
	if (a->v_attrib != b->v_attrib) {
		return -1;
	}

	if (compare_colour(&a->v_fg, &b->v_fg) != 0) {
		return -1;
	}

	if (compare_colour(&a->v_bg, &b->v_bg) != 0) {
		return -1;
	}

	return 0;
}

static void put_ansi_attrib(struct s_tty *tty, const char *s)
{
	if (tty->t_mcount > 0) {
		fputs(";", tty->t_out);
	}

	fputs(s, tty->t_out);
	tty->t_mcount++;
}

static void set_attrib(WORD *attrp, enum s_tty_attrib old, enum s_tty_attrib new)
{
	if (old == new) {
		return;
	}

	WORD attrib = *attrp;

	/* Bold ON */
	if (!(old & TTY_ATTRIB_BOLD) && new & TTY_ATTRIB_BOLD) {
		attrib |= FOREGROUND_INTENSITY;
	}

	/* Bold OFF */
	if (old & TTY_ATTRIB_BOLD && !(new & TTY_ATTRIB_BOLD)) {
		attrib &= ~FOREGROUND_INTENSITY;
	}

	/* Underline ON */
	if (!(old & TTY_ATTRIB_UNDERLINE) && new & TTY_ATTRIB_UNDERLINE) {
		attrib |= COMMON_LVB_UNDERSCORE;
	}

	/* Underline OFF */
	if (old & TTY_ATTRIB_UNDERLINE && !(new & TTY_ATTRIB_UNDERLINE)) {
		attrib &= ~COMMON_LVB_UNDERSCORE;
	}

	/* Italic ON */
	if (!(old & TTY_ATTRIB_ITALIC) && new & TTY_ATTRIB_ITALIC) {
		/* not supported */
	}

	/* Italic OFF */
	if (old & TTY_ATTRIB_ITALIC && !(new & TTY_ATTRIB_ITALIC)) {
		/* not supported */
	}

	*attrp = attrib;
}

static void set_fg(
	WORD *attrp, const struct s_tty_colour *old,
	const struct s_tty_colour *new)
{
	if (compare_colour(old, new) == 0) {
		return;
	}

	WORD attrib = *attrp;
	attrib
		&= ~(FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE
	             | FOREGROUND_INTENSITY);

	switch (new->c_mode) {
	case TTY_COLOUR_16:
		attrib |= ansi_colour16_fg[new->c_16.value];
		break;
	default:
		attrib |= FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE;
		break;
	}

	*attrp = attrib;
}

static void set_bg(
	WORD *attrp, const struct s_tty_colour *old,
	const struct s_tty_colour *new)
{
	if (compare_colour(old, new) == 0) {
		return;
	}

	WORD attrib = *attrp;
	attrib
		&= ~(BACKGROUND_RED | BACKGROUND_GREEN | BACKGROUND_BLUE
	             | BACKGROUND_INTENSITY);

	switch (new->c_mode) {
	case TTY_COLOUR_16:
		attrib |= ansi_colour16_bg[new->c_16.value];
		break;
	default:
		attrib |= BACKGROUND_RED | BACKGROUND_GREEN | BACKGROUND_BLUE;
		break;
	}
}

void s_tty_set_vmode(struct s_tty *tty, const struct s_tty_vmode *vmode)
{
	if (compare_vmode(&tty->t_vmode, vmode) == 0) {
		return;
	}

	tty->t_mcount = 0;

	WORD attrib = 0;

	set_attrib(&attrib, tty->t_vmode.v_attrib, vmode->v_attrib);
	set_fg(&attrib, &tty->t_vmode.v_fg, &vmode->v_fg);
	set_bg(&attrib, &tty->t_vmode.v_bg, &vmode->v_bg);

	SetConsoleTextAttribute(tty->t_out, attrib);

	memcpy(&tty->t_vmode, vmode, sizeof *vmode);
}

s_keycode s_tty_read_key(struct s_tty *tty)
{
	if (tty->t_repeat_count > 0) {
		tty->t_repeat_count--;
		return tty->t_repeat_key;
	}

	INPUT_RECORD d;
	HANDLE in = tty->t_in;
	BOOL status = TRUE;
	CONSOLE_READCONSOLE_CONTROL ctrl = {0};
	DWORD nr_read = 0;

	while (1) {
		status = ReadConsoleInputA(in, &d, 1, &nr_read);
		if (status == FALSE) {
			return S_KEY_EOF;
		}

		if (d.EventType != KEY_EVENT) {
			continue;
		}

		if (!d.Event.KeyEvent.bKeyDown) {
			continue;
		}

		s_keycode key = 0;

		

		switch (d.Event.KeyEvent.wVirtualKeyCode) {
		case VK_CONTROL:
		case VK_RCONTROL:
		case VK_SHIFT:
		case VK_RSHIFT:
		case VK_MENU:
			continue;
		case VK_UP:
			key = S_KEY_ARROW_UP;
			break;
		case VK_DOWN:
			key = S_KEY_ARROW_DOWN;
			break;
		case VK_LEFT:
			key = S_KEY_ARROW_LEFT;
			break;
		case VK_RIGHT:
			key = S_KEY_ARROW_RIGHT;
			break;
		case VK_BACK:
			key = S_KEY_BACKSPACE;
			break;
		case VK_RETURN:
			key = S_KEY_RETURN;
			break;
		default:
			if (d.Event.KeyEvent.uChar.UnicodeChar == 0) {
				continue;
			}

			key = d.Event.KeyEvent.uChar.AsciiChar;
			break;
		}

		if (d.Event.KeyEvent.dwControlKeyState & LEFT_CTRL_PRESSED) {
			key = S_TTY_CTRL_KEY('a' + key - 1);
		}

		if (d.Event.KeyEvent.wRepeatCount > 1) {
			tty->t_repeat_count = d.Event.KeyEvent.wRepeatCount - 1;
			tty->t_repeat_key = key;
		}

		return key;
	}

	return S_KEY_EOF;
}

void s_tty_move_cursor_x(
	struct s_tty* tty, enum s_tty_position_base base, int pos)
{
	CONSOLE_SCREEN_BUFFER_INFO console = {0};
	GetConsoleScreenBufferInfo(tty->t_out, &console);
	COORD cursor_pos;
	cursor_pos.Y = console.dwCursorPosition.Y;

	switch (base) {
	case TTY_POS_CURSOR:
		cursor_pos.X = console.dwCursorPosition.X + pos;
		break;
	case TTY_POS_START:
		cursor_pos.X = pos;
		break;
	default:
		break;
	}
		
	SetConsoleCursorPosition(tty->t_out, cursor_pos);
}

void s_tty_move_cursor_y(struct s_tty *tty, enum s_tty_position_base base, int pos)
{
	CONSOLE_SCREEN_BUFFER_INFO console = {0};
	GetConsoleScreenBufferInfo(tty->t_out, &console);
	COORD cursor_pos;
	cursor_pos.X = console.dwCursorPosition.X;

	switch (base) {
	case TTY_POS_CURSOR:
		cursor_pos.Y = console.dwCursorPosition.Y + pos;
		break;
	case TTY_POS_START:
		cursor_pos.Y = pos;
		break;
	default:
		break;
	}

	SetConsoleCursorPosition(tty->t_out, cursor_pos);
}

void s_tty_clear(struct s_tty *tty, enum s_tty_clear_mode mode)
{
	CONSOLE_SCREEN_BUFFER_INFO console = {0};
	GetConsoleScreenBufferInfo(tty->t_out, &console);

	WCHAR fill = L' ';
	DWORD length = 0;
	COORD start;

	DWORD all_length = 0, line_length = 0;

	if (mode & TTY_CLEAR_ALL) {
		line_length = console.dwSize.X;
		all_length = line_length * console.dwSize.Y;
	} else if (mode & TTY_CLEAR_FROM_CURSOR) {
		line_length = console.dwSize.X - console.dwCursorPosition.X + 1;
		all_length = line_length + ((console.dwSize.Y - console.dwCursorPosition.Y) * console.dwSize.X);
	} else if (mode & TTY_CLEAR_TO_CURSOR) {
		line_length = console.dwCursorPosition.X;
		all_length = line_length
		           + ((console.dwCursorPosition.Y - 1) * console.dwSize.X);
	} else {
		abort();
	}

	if (mode & TTY_CLEAR_SCREEN) {
		length = all_length;

		if ((mode & TTY_CLEAR_ALL) || (mode & TTY_CLEAR_TO_CURSOR)) {
			start.X = 0;
			start.Y = 0;
		} else if (mode & TTY_CLEAR_FROM_CURSOR) {
			start = console.dwCursorPosition;
		}
	} else if (mode & TTY_CLEAR_LINE) {
		length = line_length;

		if ((mode & TTY_CLEAR_ALL) || (mode & TTY_CLEAR_TO_CURSOR)) {
			start.X = 0;
			start.Y = console.dwCursorPosition.Y;
		} else if (mode & TTY_CLEAR_FROM_CURSOR) {
			start = console.dwCursorPosition;
		}
	} else {
		abort();
	}

	DWORD nr_written = 0;
	FillConsoleOutputCharacterW(tty->t_out, fill, length, start, &nr_written);
}