[bits 32]

; 32-bit protected print helpers
; VGA is 80 x 25 characters starting at 0xb8000
; 1st byte is ASCII code of char to display, 2nd byte is display info
; Address of particular row/col as: 0xb8000 + 2 * (row * 80 + col)

; Constants
i_video_memory equ 0xb8000
i_white_on_black equ 0x0f

; Variables
i_print32_row_start equ 0xb8000
i_print32_row_current equ 0xb8000
i_print32_row_end equ 0xb8002 + 160

print32_raw_simple:
	; prints null-terminated string pointed to by edx
	pusha
	mov edx, i_video_memory  ; set edx to start of the row

	print32_raw_simple_loop:
		mov al, [ebx]  ; store char at ebx in al
		mov ah, i_white_on_black  ; store display info in ah

		cmp al, 0  ; if al is null, then this is the end of the string
		je g_return

		mov [edx], ax  ; store char and attributes at current char cell

		add ebx, 1  ; increment ebx to next char in string
		add edx, 2  ; move to next char cell in video memory

		jmp print32_raw_simple_loop


print32_newline:  ; TODO fix this...
	pusha
	mov eax, i_print32_row_start
	mov ebx, i_print32_row_current
	mov ecx, i_print32_row_end
	add eax, 0xa0
	add ebx, 0xa0
	mov ecx, eax
	jmp g_return


print32_raw:
	; prints null-terminated string pointed to by edx
	pusha
	mov edx, i_print32_row_current  ; set edx to start of the row

	jmp print32_raw_loop
	print32_raw_next_line:
		call print32_newline

	print32_raw_loop:
		cmp edx, i_print32_row_end
		je print32_raw_next_line

		mov al, [ebx]  ; store char at ebx in al
		mov ah, i_white_on_black  ; store display info in ah

		cmp al, 0  ; if al is null, then this is the end of the string
		je g_return

		mov [edx], ax  ; store char and attributes at current char cell

		add ebx, 1  ; increment ebx to next char in string
		add edx, 2  ; move to next char cell in video memory

		jmp print32_raw_loop


print32:
	call print32_raw
	call print32_newline
	ret

[bits 16]