from commands.base import BaseCommand
from commands.exceptions import CommandException
from commands.invoker import Invoker


class Command1(BaseCommand):
    def build(self):
        return "touch content.txt"

    def build_undo(self):
        return "rm content.txt"


class Command2(BaseCommand):
    def build(self):
        return "mv content.txt content-replaced.txt"

    def build_undo(self):
        return "mv content-replaced.txt content.txt"


class InvalidCommand(BaseCommand):
    def build(self):
        raise CommandException()

from commands.invoker import Invoker


invoker = Invoker()

invoker.execute([
    Command1(),
    Command2(),
], run_undo=False)

# output
running command: touch content.txt
running command: mv content.txt content-replaced.txt


# If a invoker.undo() is called then all commands undo operation will be done in the LIFO order.

invoker.undo()

# output
running undo command: mv content-replaced.txt content.txt
running undo command: rm content.txt


# If a invoker.execute() is called with run_undo as True, then the undo operation will be done always
# that a command raise CommandException

invoker = Invoker()

invoker.execute([
    Command1(),
    Command2(),
    InvalidCommand(),
], run_undo=True)

# output
running command: touch content.txt
running command: mv content.txt content-replaced.txt
running command: touch content.txt
running command: mv content.txt content-replaced.txt
running undo command: mv content-replaced.txt content.txt
running undo command: rm content.txt