from dataclasses import dataclass

from parsers.state_machine import End, Start, State, StateMachine, StateResult


@dataclass
class DummyExecutionContext:
    count: int

    def to_debug(self):
        return {"count": self.count}


class GenericTestState(State):
    def __init__(self, name, next_state, fork=None):
        super().__init__(name=name, next_states=[next_state])
        self.next_state = next_state
        self.fork = fork

    def run(self, state_context) -> StateResult:
        return StateResult(self.next_state, self.fork)

    def __repr__(self):
        return f"(GenericTestState {self.name} -> {self.next_state}, forks={len(self.fork) if self.fork else 0})"


def test_i_can_execute_a_workflow():
    wkf_as_list = [Start("start", ["a"]),
                   GenericTestState("a", "b"),
                   GenericTestState("b", "c"),
                   GenericTestState("c", "end"),
                   End("end", None)]

    wkf = {state.name: state for state in wkf_as_list}

    state_machine = StateMachine({"#wkf": wkf})
    state_machine.run("#wkf", "start", DummyExecutionContext(0))

    assert len(state_machine.paths) == 1
    assert state_machine.paths[0].get_audit_trail() == ["#wkf:start", "#wkf:a", "#wkf:b", "#wkf:c", "#wkf:end"]


def test_i_can_change_workflow():
    wkf1_as_list = [Start("start", ["a"]),
                    GenericTestState("a", "#wkf2")]

    wkf2_as_list = [Start("start", ["c"]),
                    GenericTestState("c", "end"),
                    End("end", None)]

    wkfs = {
        "#wkf1": {state.name: state for state in wkf1_as_list},
        "#wkf2": {state.name: state for state in wkf2_as_list}
    }

    state_machine = StateMachine(wkfs)
    state_machine.run("#wkf1", "start", DummyExecutionContext(0))

    assert len(state_machine.paths) == 1
    assert state_machine.paths[0].get_audit_trail() == ["#wkf1:start", "#wkf1:a", "#wkf2:start", "#wkf2:c", "#wkf2:end"]


def test_i_can_fork_path():
    wkf_as_list = [Start("start", ["a"]),
                   GenericTestState("a", "end", [("b", DummyExecutionContext(i)) for i in range(3)]),
                   GenericTestState("b", "end"),
                   End("end", None)]

    wkf = {state.name: state for state in wkf_as_list}

    state_machine = StateMachine({"#wkf": wkf})
    state_machine.run("#wkf", "start", DummyExecutionContext(0))

    assert len(state_machine.paths) == 4
    assert state_machine.paths[0].get_audit_trail() == ["#wkf:start", "#wkf:a", "#wkf:end"]
    assert state_machine.paths[0].history[1].forks == [1, 2, 3]
    assert state_machine.paths[1].get_audit_trail() == ["#wkf:start", "#wkf:a", "#wkf:b", "#wkf:end"]
    assert state_machine.paths[1].history[0].parents == [0]
    assert state_machine.paths[2].get_audit_trail() == ["#wkf:start", "#wkf:a", "#wkf:b", "#wkf:end"]
    assert state_machine.paths[2].history[0].parents == [0]
    assert state_machine.paths[3].get_audit_trail() == ["#wkf:start", "#wkf:a", "#wkf:b", "#wkf:end"]
    assert state_machine.paths[3].history[0].parents == [0]