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section .bss
input_buffer resb 250
section .text
global input
global read_input
global start_screen
extern direction
extern exit
extern timespec
extern write_pause_message
extern write_start_message
input:
call read_input
call handle_input
ret
handle_input:
mov ah, byte [direction]
cmp al, 'w'
je _input_up
cmp al, 's'
je _input_down
cmp al, 'a'
je _input_left
cmp al, 'd'
je _input_right
cmp al, 27 ; escape
je _pause
ret
_pause:
mov byte [input_buffer], 'w'
call pause
ret
_input_up:
cmp ah, 1
jnz _set_up
ret
_set_up:
mov byte [direction], 3
ret
_input_down:
cmp ah, 3
jnz _set_down
ret
_set_down:
mov byte [direction], 1
ret
_input_left:
cmp ah, 0
jnz _set_left
ret
_set_left:
mov byte [direction], 2
ret
_input_right:
cmp ah, 2
jnz _set_right
ret
_set_right:
mov byte [direction], 0
ret
read_input:
mov rax, 0
mov rdi, 0
mov rsi, input_buffer
mov rdx, 250
syscall
mov al, byte [input_buffer]
ret
pause:
call write_pause_message
mov rax, 35
lea rdi, [timespec]
xor rsi, rsi
syscall
call read_input
cmp al, 'q'
je exit
cmp al, 27 ; esc
jne pause
mov byte [input_buffer], '0'
ret
start_screen:
call write_start_message
mov rax, 35
lea rdi, [timespec]
xor rsi, rsi
syscall
call read_input
cmp al, 'q'
je exit
cmp al, 32 ; space
jne start_screen
mov byte [input_buffer], '0'
ret
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