from __future__ import print_function, unicode_literals

from ctypes import windll

from dragonfly import (ActionBase, Choice, Grammar, IntegerRef, Key,
                       MappingRule, Mouse, Pause, Repeat)
from dragonfly.actions.keyboard import Keyboard, KeySymbols

KEYBOARD = Keyboard()

GET_ASYNC_KEY_STATE = windll.user32.GetAsyncKeyState


class ModifierAction(ActionBase):
    """
    Wrap arbitrary actions within keyboard presses.
    Currently Windows-only.
    """

    def __init__(self, action, modifiers=None):
        """
        Set `Action` instance to execute and prime modifiers list.

        `modifiers` must be a sequence of valid Windows keyboard codes.
        """
        super(ModifierAction, self).__init__()
        self.action = action
        if not (isinstance(modifiers, (list, tuple)) or modifiers is None):
            raise TypeError("`modifiers` must be a list, tuple, or `None`.")
        self._modifiers = tuple(modifiers) if modifiers else []

    def _execute(self, data=None):
        modifiers = list(self._modifiers)
        for key, value in data.items():
            if "modifier_" in key:
                modifiers.append(value)

        #  Only activate modifier keys which aren't currently being held down,
        #  the assumption being the keys are being held down for a reason.
        modifiers_down = [(modifier, True, .1)
                          for modifier in modifiers
                          if GET_ASYNC_KEY_STATE(modifier) & 0x8000 == 0]
        KEYBOARD.send_keyboard_events(modifiers_down)

        self.action.execute(data)

        #  Similar to before, only release keys that are being held and
        #  we are responsible for pressing.
        modifiers_up = [(modifier, False, .1)
                        for (modifier, i, j) in modifiers_down
                        if (GET_ASYNC_KEY_STATE(modifier) & 0x8000) != 0]
        KEYBOARD.send_keyboard_events(modifiers_up)


GRAMMAR = Grammar("Modifier Action example")

SHIFT_KEY = KeySymbols.SHIFT
SUPER_KEY = KeySymbols.LSUPER
ALT_KEY = KeySymbols.ALT
CONTROL_KEY = KeySymbols.CONTROL
MODIFIERS = {
    "[left] alt": ALT_KEY,
    "[left] shift": SHIFT_KEY,
    "[left] control": CONTROL_KEY,
    "[left] (windows|super)": SUPER_KEY,
}


class ExampleRule(MappingRule):

    mapping = {
        "[<modifier_1>][<modifier_2>][<modifier_3>] extended <fkey>":
            ModifierAction(Key("f%(fkey)d")),
        "after [this] tab [<n>]":
            ModifierAction(Key("tab/10:%(n)d"), modifiers=[CONTROL_KEY]),
        "before [this] tab [<n>]":
            ModifierAction(
                Key("tab/10:%(n)d"), modifiers=[CONTROL_KEY, SHIFT_KEY]),
        "[<modifier_1>][<modifier_2>][<modifier_3>] punch [<n>]":
            ModifierAction(
                (Mouse("left:down") + Pause("10") + Mouse("left:up") +
                 Pause("10")) * Repeat(extra="n")),
    }
    extras = [
        IntegerRef("n", 1, 10),
        IntegerRef("fkey", 1, 25),
        Choice("modifier_1", MODIFIERS),
        Choice("modifier_2", MODIFIERS),
        Choice("modifier_3", MODIFIERS),
    ]
    defaults = {"n": 1}


GRAMMAR.add_rule(ExampleRule())
GRAMMAR.load()


def unload():
    global GRAMMAR
    if GRAMMAR:
        GRAMMAR.unload()
    GRAMMAR = None