libs/input/rust/input.rs

/*
 * Copyright 2023 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

//! Common definitions of the Android Input Framework in rust.

use crate::ffi::RustInputDeviceIdentifier;
use bitflags::bitflags;
use inputconstants::aidl::android::os::IInputConstants;
use inputconstants::aidl::android::os::MotionEventFlag::MotionEventFlag;
use serde::{Deserialize, Serialize};
use std::fmt;

/// The InputDevice ID.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub struct DeviceId(pub i32);

/// The InputDevice equivalent for Rust inputflinger
#[derive(Debug)]
pub struct InputDevice {
    /// InputDevice ID
    pub device_id: DeviceId,
    /// InputDevice unique identifier
    pub identifier: RustInputDeviceIdentifier,
    /// InputDevice classes (equivalent to EventHub InputDeviceClass)
    pub classes: DeviceClass,
}

#[repr(u32)]
pub enum SourceClass {
    None = input_bindgen::AINPUT_SOURCE_CLASS_NONE,
    Button = input_bindgen::AINPUT_SOURCE_CLASS_BUTTON,
    Pointer = input_bindgen::AINPUT_SOURCE_CLASS_POINTER,
    Navigation = input_bindgen::AINPUT_SOURCE_CLASS_NAVIGATION,
    Position = input_bindgen::AINPUT_SOURCE_CLASS_POSITION,
    Joystick = input_bindgen::AINPUT_SOURCE_CLASS_JOYSTICK,
}

bitflags! {
    /// Source of the input device or input events.
    #[derive(Debug, PartialEq)]
    pub struct Source: u32 {
        // Constants from SourceClass, added here for compatibility reasons
        /// SourceClass::Button
        const SourceClassButton = SourceClass::Button as u32;
        /// SourceClass::Pointer
        const SourceClassPointer = SourceClass::Pointer as u32;
        /// SourceClass::Navigation
        const SourceClassNavigation = SourceClass::Navigation as u32;
        /// SourceClass::Position
        const SourceClassPosition = SourceClass::Position as u32;
        /// SourceClass::Joystick
        const SourceClassJoystick = SourceClass::Joystick as u32;

        /// SOURCE_UNKNOWN
        const Unknown = input_bindgen::AINPUT_SOURCE_UNKNOWN;
        /// SOURCE_KEYBOARD
        const Keyboard = input_bindgen::AINPUT_SOURCE_KEYBOARD;
        /// SOURCE_DPAD
        const Dpad = input_bindgen::AINPUT_SOURCE_DPAD;
        /// SOURCE_GAMEPAD
        const Gamepad = input_bindgen::AINPUT_SOURCE_GAMEPAD;
        /// SOURCE_TOUCHSCREEN
        const Touchscreen = input_bindgen::AINPUT_SOURCE_TOUCHSCREEN;
        /// SOURCE_MOUSE
        const Mouse = input_bindgen::AINPUT_SOURCE_MOUSE;
        /// SOURCE_STYLUS
        const Stylus = input_bindgen::AINPUT_SOURCE_STYLUS;
        /// SOURCE_BLUETOOTH_STYLUS
        const BluetoothStylus = input_bindgen::AINPUT_SOURCE_BLUETOOTH_STYLUS;
        /// SOURCE_TRACKBALL
        const Trackball = input_bindgen::AINPUT_SOURCE_TRACKBALL;
        /// SOURCE_MOUSE_RELATIVE
        const MouseRelative = input_bindgen::AINPUT_SOURCE_MOUSE_RELATIVE;
        /// SOURCE_TOUCHPAD
        const Touchpad = input_bindgen::AINPUT_SOURCE_TOUCHPAD;
        /// SOURCE_TOUCH_NAVIGATION
        const TouchNavigation = input_bindgen::AINPUT_SOURCE_TOUCH_NAVIGATION;
        /// SOURCE_JOYSTICK
        const Joystick = input_bindgen::AINPUT_SOURCE_JOYSTICK;
        /// SOURCE_HDMI
        const HDMI = input_bindgen::AINPUT_SOURCE_HDMI;
        /// SOURCE_SENSOR
        const Sensor = input_bindgen::AINPUT_SOURCE_SENSOR;
        /// SOURCE_ROTARY_ENCODER
        const RotaryEncoder = input_bindgen::AINPUT_SOURCE_ROTARY_ENCODER;
    }
}

/// A rust enum representation of a MotionEvent action.
#[repr(u32)]
pub enum MotionAction {
    /// ACTION_DOWN
    Down = input_bindgen::AMOTION_EVENT_ACTION_DOWN,
    /// ACTION_UP
    Up = input_bindgen::AMOTION_EVENT_ACTION_UP,
    /// ACTION_MOVE
    Move = input_bindgen::AMOTION_EVENT_ACTION_MOVE,
    /// ACTION_CANCEL
    Cancel = input_bindgen::AMOTION_EVENT_ACTION_CANCEL,
    /// ACTION_OUTSIDE
    Outside = input_bindgen::AMOTION_EVENT_ACTION_OUTSIDE,
    /// ACTION_POINTER_DOWN
    PointerDown {
        /// The index of the affected pointer.
        action_index: usize,
    } = input_bindgen::AMOTION_EVENT_ACTION_POINTER_DOWN,
    /// ACTION_POINTER_UP
    PointerUp {
        /// The index of the affected pointer.
        action_index: usize,
    } = input_bindgen::AMOTION_EVENT_ACTION_POINTER_UP,
    /// ACTION_HOVER_ENTER
    HoverEnter = input_bindgen::AMOTION_EVENT_ACTION_HOVER_ENTER,
    /// ACTION_HOVER_MOVE
    HoverMove = input_bindgen::AMOTION_EVENT_ACTION_HOVER_MOVE,
    /// ACTION_HOVER_EXIT
    HoverExit = input_bindgen::AMOTION_EVENT_ACTION_HOVER_EXIT,
    /// ACTION_SCROLL
    Scroll = input_bindgen::AMOTION_EVENT_ACTION_SCROLL,
    /// ACTION_BUTTON_PRESS
    ButtonPress = input_bindgen::AMOTION_EVENT_ACTION_BUTTON_PRESS,
    /// ACTION_BUTTON_RELEASE
    ButtonRelease = input_bindgen::AMOTION_EVENT_ACTION_BUTTON_RELEASE,
}

impl fmt::Display for MotionAction {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            MotionAction::Down => write!(f, "DOWN"),
            MotionAction::Up => write!(f, "UP"),
            MotionAction::Move => write!(f, "MOVE"),
            MotionAction::Cancel => write!(f, "CANCEL"),
            MotionAction::Outside => write!(f, "OUTSIDE"),
            MotionAction::PointerDown { action_index } => {
                write!(f, "POINTER_DOWN({})", action_index)
            }
            MotionAction::PointerUp { action_index } => write!(f, "POINTER_UP({})", action_index),
            MotionAction::HoverMove => write!(f, "HOVER_MOVE"),
            MotionAction::Scroll => write!(f, "SCROLL"),
            MotionAction::HoverEnter => write!(f, "HOVER_ENTER"),
            MotionAction::HoverExit => write!(f, "HOVER_EXIT"),
            MotionAction::ButtonPress => write!(f, "BUTTON_PRESS"),
            MotionAction::ButtonRelease => write!(f, "BUTTON_RELEASE"),
        }
    }
}

impl From<u32> for MotionAction {
    fn from(action: u32) -> Self {
        let (action_masked, action_index) = MotionAction::breakdown_action(action);
        match action_masked {
            input_bindgen::AMOTION_EVENT_ACTION_DOWN => MotionAction::Down,
            input_bindgen::AMOTION_EVENT_ACTION_UP => MotionAction::Up,
            input_bindgen::AMOTION_EVENT_ACTION_MOVE => MotionAction::Move,
            input_bindgen::AMOTION_EVENT_ACTION_CANCEL => MotionAction::Cancel,
            input_bindgen::AMOTION_EVENT_ACTION_OUTSIDE => MotionAction::Outside,
            input_bindgen::AMOTION_EVENT_ACTION_POINTER_DOWN => {
                MotionAction::PointerDown { action_index }
            }
            input_bindgen::AMOTION_EVENT_ACTION_POINTER_UP => {
                MotionAction::PointerUp { action_index }
            }
            input_bindgen::AMOTION_EVENT_ACTION_HOVER_ENTER => MotionAction::HoverEnter,
            input_bindgen::AMOTION_EVENT_ACTION_HOVER_MOVE => MotionAction::HoverMove,
            input_bindgen::AMOTION_EVENT_ACTION_HOVER_EXIT => MotionAction::HoverExit,
            input_bindgen::AMOTION_EVENT_ACTION_SCROLL => MotionAction::Scroll,
            input_bindgen::AMOTION_EVENT_ACTION_BUTTON_PRESS => MotionAction::ButtonPress,
            input_bindgen::AMOTION_EVENT_ACTION_BUTTON_RELEASE => MotionAction::ButtonRelease,
            _ => panic!("Unknown action: {}", action),
        }
    }
}

impl MotionAction {
    fn breakdown_action(action: u32) -> (u32, usize) {
        let action_masked = action & input_bindgen::AMOTION_EVENT_ACTION_MASK;
        let index = (action & input_bindgen::AMOTION_EVENT_ACTION_POINTER_INDEX_MASK)
            >> input_bindgen::AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT;
        (action_masked, index.try_into().unwrap())
    }
}

bitflags! {
    /// MotionEvent flags.
    /// The source of truth for the flag definitions are the MotionEventFlag AIDL enum.
    /// The flag values are redefined here as a bitflags API.
    #[derive(Debug)]
    pub struct MotionFlags: u32 {
        /// FLAG_WINDOW_IS_OBSCURED
        const WINDOW_IS_OBSCURED = MotionEventFlag::WINDOW_IS_OBSCURED.0 as u32;
        /// FLAG_WINDOW_IS_PARTIALLY_OBSCURED
        const WINDOW_IS_PARTIALLY_OBSCURED = MotionEventFlag::WINDOW_IS_PARTIALLY_OBSCURED.0 as u32;
        /// FLAG_HOVER_EXIT_PENDING
        const HOVER_EXIT_PENDING = MotionEventFlag::HOVER_EXIT_PENDING.0 as u32;
        /// FLAG_IS_GENERATED_GESTURE
        const IS_GENERATED_GESTURE = MotionEventFlag::IS_GENERATED_GESTURE.0 as u32;
        /// FLAG_CANCELED
        const CANCELED = MotionEventFlag::CANCELED.0 as u32;
        /// FLAG_NO_FOCUS_CHANGE
        const NO_FOCUS_CHANGE = MotionEventFlag::NO_FOCUS_CHANGE.0 as u32;
        /// PRIVATE_FLAG_SUPPORTS_ORIENTATION
        const PRIVATE_FLAG_SUPPORTS_ORIENTATION =
                MotionEventFlag::PRIVATE_FLAG_SUPPORTS_ORIENTATION.0 as u32;
        /// PRIVATE_FLAG_SUPPORTS_DIRECTIONAL_ORIENTATION
        const PRIVATE_FLAG_SUPPORTS_DIRECTIONAL_ORIENTATION =
                MotionEventFlag::PRIVATE_FLAG_SUPPORTS_DIRECTIONAL_ORIENTATION.0 as u32;
        /// FLAG_IS_ACCESSIBILITY_EVENT
        const IS_ACCESSIBILITY_EVENT = MotionEventFlag::IS_ACCESSIBILITY_EVENT.0 as u32;
        /// FLAG_TAINTED
        const TAINTED = MotionEventFlag::TAINTED.0 as u32;
        /// FLAG_TARGET_ACCESSIBILITY_FOCUS
        const TARGET_ACCESSIBILITY_FOCUS = MotionEventFlag::TARGET_ACCESSIBILITY_FOCUS.0 as u32;
    }
}

impl Source {
    /// Return true if this source is from the provided class
    pub fn is_from_class(&self, source_class: SourceClass) -> bool {
        let class_bits = source_class as u32;
        self.bits() & class_bits == class_bits
    }
}

bitflags! {
    /// Device class of the input device. These are duplicated from Eventhub.h
    /// We need to make sure the two version remain in sync when adding new classes.
    #[derive(Debug, PartialEq)]
    pub struct DeviceClass: u32 {
        /// The input device is a keyboard or has buttons
        const Keyboard = IInputConstants::DEVICE_CLASS_KEYBOARD as u32;
        /// The input device is an alpha-numeric keyboard (not just a dial pad)
        const AlphabeticKey = IInputConstants::DEVICE_CLASS_ALPHAKEY as u32;
        /// The input device is a touchscreen or a touchpad (either single-touch or multi-touch)
        const Touch = IInputConstants::DEVICE_CLASS_TOUCH as u32;
        /// The input device is a cursor device such as a trackball or mouse.
        const Cursor = IInputConstants::DEVICE_CLASS_CURSOR as u32;
        /// The input device is a multi-touch touchscreen or touchpad.
        const MultiTouch = IInputConstants::DEVICE_CLASS_TOUCH_MT as u32;
        /// The input device is a directional pad (implies keyboard, has DPAD keys).
        const Dpad = IInputConstants::DEVICE_CLASS_DPAD as u32;
        /// The input device is a gamepad (implies keyboard, has BUTTON keys).
        const Gamepad = IInputConstants::DEVICE_CLASS_GAMEPAD as u32;
        /// The input device has switches.
        const Switch = IInputConstants::DEVICE_CLASS_SWITCH as u32;
        /// The input device is a joystick (implies gamepad, has joystick absolute axes).
        const Joystick = IInputConstants::DEVICE_CLASS_JOYSTICK as u32;
        /// The input device has a vibrator (supports FF_RUMBLE).
        const Vibrator = IInputConstants::DEVICE_CLASS_VIBRATOR as u32;
        /// The input device has a microphone.
        const Mic = IInputConstants::DEVICE_CLASS_MIC as u32;
        /// The input device is an external stylus (has data we want to fuse with touch data).
        const ExternalStylus = IInputConstants::DEVICE_CLASS_EXTERNAL_STYLUS as u32;
        /// The input device has a rotary encoder
        const RotaryEncoder = IInputConstants::DEVICE_CLASS_ROTARY_ENCODER as u32;
        /// The input device has a sensor like accelerometer, gyro, etc
        const Sensor = IInputConstants::DEVICE_CLASS_SENSOR as u32;
        /// The input device has a battery
        const Battery = IInputConstants::DEVICE_CLASS_BATTERY as u32;
        /// The input device has sysfs controllable lights
        const Light = IInputConstants::DEVICE_CLASS_LIGHT as u32;
        /// The input device is a touchpad, requiring an on-screen cursor.
        const Touchpad = IInputConstants::DEVICE_CLASS_TOUCHPAD as u32;
        /// The input device is virtual (not a real device, not part of UI configuration).
        const Virtual = IInputConstants::DEVICE_CLASS_VIRTUAL as u32;
        /// The input device is external (not built-in).
        const External = IInputConstants::DEVICE_CLASS_EXTERNAL as u32;
    }
}

bitflags! {
    /// Modifier state flags
    #[derive(Default, Debug, Copy, Clone, Eq, PartialEq)]
    pub struct ModifierState: u32 {
        /// No meta keys are pressed
        const None = input_bindgen::AMETA_NONE;
        /// This mask is used to check whether one of the ALT meta keys is pressed
        const AltOn = input_bindgen::AMETA_ALT_ON;
        /// This mask is used to check whether the left ALT meta key is pressed
        const AltLeftOn = input_bindgen::AMETA_ALT_LEFT_ON;
        /// This mask is used to check whether the right ALT meta key is pressed
        const AltRightOn = input_bindgen::AMETA_ALT_RIGHT_ON;
        /// This mask is used to check whether one of the SHIFT meta keys is pressed
        const ShiftOn = input_bindgen::AMETA_SHIFT_ON;
        /// This mask is used to check whether the left SHIFT meta key is pressed
        const ShiftLeftOn = input_bindgen::AMETA_SHIFT_LEFT_ON;
        /// This mask is used to check whether the right SHIFT meta key is pressed
        const ShiftRightOn = input_bindgen::AMETA_SHIFT_RIGHT_ON;
        /// This mask is used to check whether the SYM meta key is pressed
        const SymOn = input_bindgen::AMETA_SYM_ON;
        /// This mask is used to check whether the FUNCTION meta key is pressed
        const FunctionOn = input_bindgen::AMETA_FUNCTION_ON;
        /// This mask is used to check whether one of the CTRL meta keys is pressed
        const CtrlOn = input_bindgen::AMETA_CTRL_ON;
        /// This mask is used to check whether the left CTRL meta key is pressed
        const CtrlLeftOn = input_bindgen::AMETA_CTRL_LEFT_ON;
        /// This mask is used to check whether the right CTRL meta key is pressed
        const CtrlRightOn = input_bindgen::AMETA_CTRL_RIGHT_ON;
        /// This mask is used to check whether one of the META meta keys is pressed
        const MetaOn = input_bindgen::AMETA_META_ON;
        /// This mask is used to check whether the left META meta key is pressed
        const MetaLeftOn = input_bindgen::AMETA_META_LEFT_ON;
        /// This mask is used to check whether the right META meta key is pressed
        const MetaRightOn = input_bindgen::AMETA_META_RIGHT_ON;
        /// This mask is used to check whether the CAPS LOCK meta key is on
        const CapsLockOn = input_bindgen::AMETA_CAPS_LOCK_ON;
        /// This mask is used to check whether the NUM LOCK meta key is on
        const NumLockOn = input_bindgen::AMETA_NUM_LOCK_ON;
        /// This mask is used to check whether the SCROLL LOCK meta key is on
        const ScrollLockOn = input_bindgen::AMETA_SCROLL_LOCK_ON;
    }
}

/// A rust enum representation of a Keyboard type.
#[repr(u32)]
#[derive(Debug, Default, Copy, Clone, Eq, PartialEq, Serialize, Deserialize)]
#[serde(tag = "type")]
pub enum KeyboardType {
    /// KEYBOARD_TYPE_NONE
    #[default]
    None = input_bindgen::AINPUT_KEYBOARD_TYPE_NONE,
    /// KEYBOARD_TYPE_NON_ALPHABETIC
    NonAlphabetic = input_bindgen::AINPUT_KEYBOARD_TYPE_NON_ALPHABETIC,
    /// KEYBOARD_TYPE_ALPHABETIC
    Alphabetic = input_bindgen::AINPUT_KEYBOARD_TYPE_ALPHABETIC,
}

#[cfg(test)]
mod tests {
    use crate::input::SourceClass;
    use crate::MotionFlags;
    use crate::Source;
    use inputconstants::aidl::android::os::MotionEventFlag::MotionEventFlag;

    #[test]
    fn convert_source_class_pointer() {
        let source = Source::from_bits(input_bindgen::AINPUT_SOURCE_CLASS_POINTER).unwrap();
        assert!(source.is_from_class(SourceClass::Pointer));
    }

    /// Ensure all MotionEventFlag constants are re-defined in rust.
    #[test]
    fn all_motion_event_flags_defined() {
        for flag in MotionEventFlag::enum_values() {
            assert!(
                MotionFlags::from_bits(flag.0 as u32).is_some(),
                "MotionEventFlag value {flag:?} is not redefined as a rust MotionFlags"
            );
        }
    }
}