import cmds
from serial import Serial

class InUseException(Exception):
	def __str__(self):
		return f"{self.chs} is already used in plan"
	def __init__(self, chs):
		self.chs = chs

class Planner:
	def exec(self):
		for c in self.cmds:
			s = c.exec()
			if s is not None:
				self.ser.write(bytes(s, "UTF-8"))

	def add(self, cmd):
		acc = cmd.accessing()

		if len(acc) > 0:
			conflict = self.used & acc
			if len(conflict) > 0:
				raise InUseException(conflict)
			if cmd.is_async:
				self.used |= acc

		self.cmds.append(cmd)

	def __init__(self):
		self.cmds = []
		self.used = set()
		self.waiting_on = dict()
		self.ser = Serial()