#ifndef COLORS_H
#define COLORS_H

#include "stdmem.h"
#include "types.h"

#include <stdarg.h>
#include <stddef.h>
#include <stdint.h>

#define VGA_WIDTH 80
#define VGA_HEIGHT 25

#define VGA_MEMORY_ADDRESS 0xB8000

/*
 * FOR INPUT
 */

#define KEYBOARD_BUFFER_SIZE 256

#define SCANCODE_LSHIFT 0x2A
#define SCANCODE_RSHIFT 0x36
#define SCANCODE_CAPSLOCK 0x3A
#define RELEASE_MASK 0x80

static volatile unsigned char _keyboard_buffer[KEYBOARD_BUFFER_SIZE];
static volatile uint16_t _kb_head = 0;
static volatile uint16_t _kb_tail = 0;

static char __g_shift_pressed = 0;
static char __g_caps_lock_active = 0;

// C99 Designated Initializers for Unshifted ASCII Characters
static const char scancode_ascii_unshifted[128] = {
	[0x01] = 27, // ESC
	[0x02] = '1',  [0x03] = '2',  [0x04] = '3', [0x05] = '4', [0x06] = '5', [0x07] = '6', [0x08] = '7', [0x09] = '8', [0x0A] = '9', [0x0B] = '0', [0x0C] = '-',
	[0x0D] = '=',  [0x0E] = '\b', // Backspace
	[0x0F] = '\t',				  // Tab
	[0x10] = 'q',  [0x11] = 'w',  [0x12] = 'e', [0x13] = 'r', [0x14] = 't', [0x15] = 'y', [0x16] = 'u', [0x17] = 'i', [0x18] = 'o', [0x19] = 'p', [0x1A] = '[',
	[0x1B] = ']',  [0x1C] = '\n', // Enter
	[0x1E] = 'a',  [0x1F] = 's',  [0x20] = 'd', [0x21] = 'f', [0x22] = 'g', [0x23] = 'h', [0x24] = 'j', [0x25] = 'k', [0x26] = 'l', [0x27] = ';', [0x28] = '\'',
	[0x29] = '`',  [0x2C] = 'z',  [0x2D] = 'x', [0x2E] = 'c', [0x2F] = 'v', [0x30] = 'b', [0x31] = 'n', [0x32] = 'm', [0x33] = ',', [0x34] = '.', [0x35] = '/',
	[0x39] = ' ' // Spacebar
};

// C99 Designated Initializers for Shifted ASCII Characters
static const char scancode_ascii_shifted[128] = {
	[0x01] = 27, // ESC
	[0x02] = '!', [0x03] = '@', [0x04] = '#',  [0x05] = '$',  [0x06] = '%', [0x07] = '^', [0x08] = '&',	 [0x09] = '*', [0x0A] = '(', [0x0B] = ')',
	[0x0C] = '_', [0x0D] = '+', [0x0E] = '\b', [0x0F] = '\t', [0x10] = 'Q', [0x11] = 'W', [0x12] = 'E',	 [0x13] = 'R', [0x14] = 'T', [0x15] = 'Y',
	[0x16] = 'U', [0x17] = 'I', [0x18] = 'O',  [0x19] = 'P',  [0x1A] = '{', [0x1B] = '}', [0x1C] = '\n', [0x1E] = 'A', [0x1F] = 'S', [0x20] = 'D',
	[0x21] = 'F', [0x22] = 'G', [0x23] = 'H',  [0x24] = 'J',  [0x25] = 'K', [0x26] = 'L', [0x27] = ':',	 [0x28] = '"', [0x29] = '~', [0x2C] = 'Z',
	[0x2D] = 'X', [0x2E] = 'C', [0x2F] = 'V',  [0x30] = 'B',  [0x31] = 'N', [0x32] = 'M', [0x33] = '<',	 [0x34] = '>', [0x35] = '?', [0x39] = ' '};

/* IN VGA - Video Memory Arrya:
 * short
 * 1s byte (left most)  -> TEXT COLOR
 * 2s byte              -> BACK COLOR
 * 3rd and 4rt byte     -> TEXT (unsigned char) AKA CodePoint
 */

typedef struct __attribute__((packed)) _VGA {
	unsigned char codepoint; // 3rd and 4th byte
	unsigned char color;	 // 1st byte: text color, 2nd byte: background color
							 // LAST BIT IS BLINKING FLAG
} _VGA;

typedef enum _VGA_COLOR {
	BLACK = 0x0,
	BLUE = 0x1,
	GREEN = 0x2,
	CYAN = 0x3,
	RED = 0x4,
	MAGENTA = 0x5,
	BROWN = 0x6,
	LIGHT_GREY = 0x7,
	DARK_GREY = 0x8,
	LIGHT_BLUE = 0x9,
	LIGHT_GREEN = 0xA,
	LIGHT_CYAN = 0xB,
	LIGHT_RED = 0xC,
	LIGHT_MAGENTA = 0xD,
	YELLOW = 0xE,
	WHITE = 0xF
} _VGA_COLOR;

typedef struct _VGA_screen_space {
	unsigned int line;
	unsigned int column;

} _VGA_screen_space;

static _VGA_screen_space cursor_pos = {0, 0};
static _VGA_screen_space text_pos = {0, 0};

static unsigned int tab_pos = 0;

#define DEFAULT_BG BLUE
#define DEFAULT_FG WHITE

/*
 * END OF DECLARATIONS
 */

/*
 * START OF OUTPUT FUNCTIONS
 */

int printf(const char *fmt, ...);

void clear_screen();

/*
 * END OF OUTPUT FUNCTIONS
 */

/*
 * START OF INPUT FUNCTIONS
 */
void scursor(unsigned int column, unsigned int line); 

void gets(char *buffer, size_t max_length);

int scanf(const char *fmt, ...);
#endif