path: root/tools/testing/selftests/hid/tests/test_tablet.py

#!/bin/env python3
# SPDX-License-Identifier: GPL-2.0
# -*- coding: utf-8 -*-
#
# Copyright (c) 2021 Benjamin Tissoires <benjamin.tissoires@gmail.com>
# Copyright (c) 2021 Red Hat, Inc.
#

from . import base
import copy
from enum import Enum
from hidtools.util import BusType
from .base import HidBpf
import libevdev
import logging
import pytest
from typing import Dict, List, Optional, Tuple

logger = logging.getLogger("hidtools.test.tablet")


class BtnTouch(Enum):
    """Represents whether the BTN_TOUCH event is set to True or False"""

    DOWN = True
    UP = False


class ToolType(Enum):
    PEN = libevdev.EV_KEY.BTN_TOOL_PEN
    RUBBER = libevdev.EV_KEY.BTN_TOOL_RUBBER


class BtnPressed(Enum):
    """Represents whether a button is pressed on the stylus"""

    PRIMARY_PRESSED = libevdev.EV_KEY.BTN_STYLUS
    SECONDARY_PRESSED = libevdev.EV_KEY.BTN_STYLUS2
    THIRD_PRESSED = libevdev.EV_KEY.BTN_STYLUS3


class PenState(Enum):
    """Pen states according to Microsoft reference:
    https://docs.microsoft.com/en-us/windows-hardware/design/component-guidelines/windows-pen-states

    We extend it with the various buttons when we need to check them.
    """

    PEN_IS_OUT_OF_RANGE = BtnTouch.UP, None, False
    PEN_IS_IN_RANGE = BtnTouch.UP, ToolType.PEN, False
    PEN_IS_IN_RANGE_WITH_BUTTON = BtnTouch.UP, ToolType.PEN, True
    PEN_IS_IN_CONTACT = BtnTouch.DOWN, ToolType.PEN, False
    PEN_IS_IN_CONTACT_WITH_BUTTON = BtnTouch.DOWN, ToolType.PEN, True
    PEN_IS_IN_RANGE_WITH_ERASING_INTENT = BtnTouch.UP, ToolType.RUBBER, False
    PEN_IS_IN_RANGE_WITH_ERASING_INTENT_WITH_BUTTON = BtnTouch.UP, ToolType.RUBBER, True
    PEN_IS_ERASING = BtnTouch.DOWN, ToolType.RUBBER, False
    PEN_IS_ERASING_WITH_BUTTON = BtnTouch.DOWN, ToolType.RUBBER, True

    def __init__(
        self, touch: BtnTouch, tool: Optional[ToolType], button: Optional[bool]
    ):
        self.touch = touch  # type: ignore
        self.tool = tool  # type: ignore
        self.button = button  # type: ignore

    @classmethod
    def from_evdev(cls, evdev, test_button) -> "PenState":
        touch = BtnTouch(evdev.value[libevdev.EV_KEY.BTN_TOUCH])
        tool = None
        button = False
        if (
            evdev.value[libevdev.EV_KEY.BTN_TOOL_RUBBER]
            and not evdev.value[libevdev.EV_KEY.BTN_TOOL_PEN]
        ):
            tool = ToolType(libevdev.EV_KEY.BTN_TOOL_RUBBER)
        elif (
            evdev.value[libevdev.EV_KEY.BTN_TOOL_PEN]
            and not evdev.value[libevdev.EV_KEY.BTN_TOOL_RUBBER]
        ):
            tool = ToolType(libevdev.EV_KEY.BTN_TOOL_PEN)
        elif (
            evdev.value[libevdev.EV_KEY.BTN_TOOL_PEN]
            or evdev.value[libevdev.EV_KEY.BTN_TOOL_RUBBER]
        ):
            raise ValueError("2 tools are not allowed")

        # we take only the provided button into account
        if test_button is not None:
            button = bool(evdev.value[test_button.value])

        # the kernel tends to insert an EV_SYN once removing the tool, so
        # the button will be released after
        if tool is None:
            button = False

        return cls((touch, tool, button))  # type: ignore

    def apply(
        self, events: List[libevdev.InputEvent], strict: bool, test_button: BtnPressed
    ) -> "PenState":
        if libevdev.EV_SYN.SYN_REPORT in events:
            raise ValueError("EV_SYN is in the event sequence")
        touch = self.touch
        touch_found = False
        tool = self.tool
        tool_found = False
        button = self.button
        button_found = False

        for ev in events:
            if ev == libevdev.InputEvent(libevdev.EV_KEY.BTN_TOUCH):
                if touch_found:
                    raise ValueError(f"duplicated BTN_TOUCH in {events}")
                touch_found = True
                touch = BtnTouch(ev.value)
            elif ev in (
                libevdev.InputEvent(libevdev.EV_KEY.BTN_TOOL_PEN),
                libevdev.InputEvent(libevdev.EV_KEY.BTN_TOOL_RUBBER),
            ):
                if tool_found:
                    raise ValueError(f"duplicated BTN_TOOL_* in {events}")
                tool_found = True
                tool = ToolType(ev.code) if ev.value else None
            elif test_button is not None and ev in (test_button.value,):
                if button_found:
                    raise ValueError(f"duplicated BTN_STYLUS* in {events}")
                button_found = True
                button = bool(ev.value)

        # the kernel tends to insert an EV_SYN once removing the tool, so
        # the button will be released after
        if tool is None:
            button = False

        new_state = PenState((touch, tool, button))  # type: ignore
        if strict:
            assert (
                new_state in self.valid_transitions()
            ), f"moving from {self} to {new_state} is forbidden"
        else:
            assert (
                new_state in self.historically_tolerated_transitions()
            ), f"moving from {self} to {new_state} is forbidden"

        return new_state

    def valid_transitions(self) -> Tuple["PenState", ...]:
        """Following the state machine in the URL above.

        Note that those transitions are from the evdev point of view, not HID"""
        if self == PenState.PEN_IS_OUT_OF_RANGE:
            return (
                PenState.PEN_IS_OUT_OF_RANGE,