# target parva_0_1

li sp, stack

# function
tokenize:
	push ra
	addi x2, a0, -1 # x2 = pointer to input string

	li x0, -1
	push x0 # mark the beginning of the token stack

tokenize__loop:
	addi x2, x2, 1
	lw x3, x2
	beqz x3, tokenize__end
	li x4, '0'
	blt x3, x4, tokenize__symbol
	li x5, '9'
	bgt x3, x5, tokenize__symbol

	mv x6, sp
.align 2
tokenize__number_gather:
	push x3
	addi x2, x2, 1
	addi x3, x3, -'0'
	lw x3, x2
	blt x3, x4, tokenize__number_gather_end
	bgt x3, x5, tokenize__number_gather_end
	b tokenize__number_gather
tokenize__number_gather_end:
	li x0, 0 # x0 = sum
	li x7, 1 # x7 = power of 10
.align 2
tokenize__number_sum:
	pop x3
	mulu x3, x3, x7
	add x0, x0, x3
	mului x7, x7, 10
	bne x6, sp, tokenize__number_sum

	li x3, 1 # token type = 1 = number
	push x3
	push x0
	b tokenize__loop

tokenize__symbol:
	xori x3, x3, 42 # todo, set to appropriate value for hashing symbols
	lw x3, tokenize__symbol_hashtable(x3)
	beqz x3, error_invalid_input
	push x3
	b tokenize__loop

tokenize__end:

tokenize__shunting_yard:
	pop x3
	bnez x3, 3
	


b end

tokenize__output_queue:
	.repeat 0 40

tokenize__symbol_hashtable:
	.data 0
	.data 1
	.repeat 0 30 # todo

error_invalid_input:
	li a0, error_message_invalid_input
	li a1, 1
	call print
	b end

# function
print:
	# todo
	ret

end:
	wfi

input_string:
.string_encoding terminal
.string "125+23*8"
.string "\0"

error_message_invalid_input:
.string_encoding ascii # todo, use correct encoding
.string "Invalid input\0"

stack: