extern	NR_write
extern	strlen
extern	strcat
extern	itoa

section .rodata
	NL		db	0xA
section .bss
	printfBuff	resb	4096
	printfNBuff	resb	32
section .text
	global	print
	global	puts
	global	printf

;----- print (char* string) -----;
; return value: N/A
print:
	push	rbp
	mov	rbp, rsp

	call	strlen
	mov	rdx, rax
	mov	rax, NR_write
	mov	rsi, rdi
	mov	rdi, 1
	syscall

	leave
	ret
;----- puts (char* string) -----;
; return  value: N/A
puts:
	push	rbp
	mov	rbp, rsp

	mov	r10, rdi
	call	print
	mov	rdi, r10
	mov	rax, NR_write
	mov	rdi, 1
	mov	rsi, NL
	mov	rdx, 1
	syscall

	leave
	ret
;----- printf(const char* string, ...) -----;
printf:
	push	rbp
	mov	rbp, rsp

	push	r12
	push	r13

	xor	r10, r10
	lea	r11, [rel printfBuff]
	.makeStr:
		cmp	byte [rdi], 0x0
		je	.finish
		cmp	byte [rdi], '%'
		je	.replaceArg
		mov	r12b, byte [rdi]
		mov	byte [r11], r12b
		jmp	.continue
		.replaceArg:
			cmp	byte [rdi+1], 0x0
			je	.continue
			push	rdi
			cmp	byte [rdi+1], 'd'
			je	.rep_d
			cmp	byte [rdi+1], 's'
			je	.rep_s

			;--- %d ---;
			.rep_d:
			cmp	r10, 0
			je	.rep_d_rsi
			cmp	r10, 1
			je	.rep_d_rdx
			cmp	r10, 2
			je	.rep_d_rcx
			cmp	r10, 3
			je	.rep_d_r8
			cmp	r10, 4
			je	.rep_d_r9

			;get from stack
			mov	rsi, qword [rbp + 16 + (r10-5)*8]
			jmp	.convertInt

			.rep_d_rsi:
				mov	rdi, rsi
				jmp	.convertInt
			.rep_d_rdx:
				mov	rdi, rdx
				jmp	.convertInt
			.rep_d_rcx:
				mov	rdi, rcx
				jmp	.convertInt
			.rep_d_r8:
				mov	rdi, r8
				jmp	.convertInt
			.rep_d_r9:
				mov	rdi, r9

			.convertInt:
				lea	rsi, [rel printfNBuff]
				push	rcx
				push	rdx
				push	r8
				push	r10
				push	rsi
				call	itoa
				pop	rsi
				pop	r10
				pop	r8
				pop	rdx
				pop	rcx
				mov	rsi, rax
				jmp	.sinsertLoop

			;--- %s ---;
			.rep_s:
			cmp	r10, 0
			je	.sinsertLoop ;nothing to do, rsi already correct
			cmp	r10, 1
			je	.rep_s_rdx
			cmp	r10, 2
			je	.rep_s_rcx
			cmp	r10, 3
			je	.rep_s_r8
			cmp	r10, 4
			je	.rep_s_r9

			;get from stack
			mov	rsi, qword [rbp + 16 + (r10-5)*8]
			jmp	.sinsertLoop

			.rep_s_rdx:
			mov	rsi, rdx
			jmp	.sinsertLoop
			.rep_s_rcx:
			mov	rsi, rcx
			jmp	.sinsertLoop
			.rep_s_r8:
			mov	rsi, r8
			jmp	.sinsertLoop
			.rep_s_r9:
			mov	rsi, r9

			.sinsertLoop:
				cmp	byte [rsi], 0x0
				je	.s0f
				mov	r13b, byte [rsi]
				mov	byte [r11], r13b
				inc	rsi
				inc	r11
				jmp	.sinsertLoop
			.s0f:
			inc	r10
			pop	rdi
			add	rdi, 2
			jmp	.makeStr
		.continue:
		inc	rdi
		inc	r11
		jmp	.makeStr
	.finish:
	mov	byte [r11], 0x0
	lea	rdi, [rel printfBuff]
	call	print

	pop	r13
	pop	r12

	leave
	ret