magic_mapper.py

import os
import re
import sys
import time
import traceback
import struct
import subprocess
import json
import fcntl

# We need the socket library for send_tcp_command(), but this isn't always installed in WebOS
try:
    import socket
    SOCKET_AVAILABLE = True
except ImportError:
    SOCKET_AVAILABLE = False

# We need select to read more than one input device (the IR receiver), it may be missing too
try:
    import select
    SELECT_AVAILABLE = True
except ImportError:
    SELECT_AVAILABLE = False

VERSION = "1.1.0"

# Default settings. Don't edit these here, override them in the "magic_mapper_settings"
# section of magic_mapper_config.json instead (see the Settings section of the README)
BLOCK_MOUSE = False  # block_mouse: disable the mouse, requires EXCLUSIVE_MODE
EXCLUSIVE_MODE = True  # exclusive_mode: prevent bound codes from the input device from being seen by WebOS
INPUT_DEVICE_NAME = 'LGE M-RCU - Builtin [0]'  # input_device_name: the exact Name= shown in /proc/bus/input/devices
IR_INPUT_ENABLED = False  # ir_input_enabled: also read button presses from the IR receiver
IR_INPUT_DEVICE_NAME = 'LGE RCU'  # ir_input_device_name: the exact Name= of the IR receiver in /proc/bus/input/devices
IR_EXCLUSIVE_MODE = True  # ir_exclusive_mode: grab the IR device so mapped IR buttons don't also do their normal action
OUTPUT_DEVICE_NAME = 'LGE M-RCU - Builtin [2]'  # output_device_name: unbound codes get resent to this device in exclusive mode
# If OUTPUT_DEVICE_NAME isn't found, another 'LGE M-RCU - Builtin [N]' device is picked automatically
INPUT_DEVICE_NAME_SET = False  # True when input_device_name was set in the config
OUTPUT_DEVICE_NAME_SET = False  # True when output_device_name was set in the config
# On webOS 10+, keys resent through Builtin [2] make Back exit the app instead of closing menus,
# so Builtin [1] is preferred there unless output_device_name is set
WEBOS_10_OUTPUT_DEVICE_NAME = 'LGE M-RCU - Builtin [1]'
WEBOS_MAJOR_VERSION = 0  # set in main()


BUTTONS = {
    398: "red",
    399: "green",
    400: "yellow",
    401: "blue",
    402: "ch_up",
    403: "ch_down",
    115: "vol_up",
    114: "vol_down",
    207: "play",
    119: "pause",
    128: "stop",
    167: "record",
    168: "rewind",
    208: "fastforward",
    2: "1",
    3: "2",
    4: "3",
    5: "4",
    6: "5",
    7: "6",
    8: "7",
    9: "8",
    10: "9",
    11: "0",
    1038: "prime",
    1107: "sling",
    1037: "netflix",
    1042: "disney",
    1043: "lg_channels",
    1044: "rakuten",
    1086: "alexa",
    1117: "google",
    362: "guide",
    428: "voice",
    771: "channels",
    787: "channels_alt",  # seen on an LG IR remote
    994: "...",
    799: "...alt",  # seen on an LG IR remote, button with three dots surrounded by a rectangle
    1083: "search",
    217: "search_alt",  # seen on an LG IR remote
    174: "exit",  # seen on an LG IR remote, appears to exit apps
    829: "sap",
    1116: "tv",
    358: "info",
    773: "home",
    28: "ok",
    412: "back",
    1123: "home_hub",
    1124: "accessibility",
    139: "settings",
    103: "up",
    108: "down",
    105: "left",
    106: "right",
}

MOUSE_WHEEL = {
     1: "wheel_up",
    -1: "wheel_down"
}

EVIOCGRAB = 1074021776  # Don't mess with this


def cycle_energy_mode(inputs):
    """cycle energy modes between min med max off"""
    modes = ["max", "med", "min", "off"]
    if inputs.get("reverse_order"):
        modes.reverse()
    current_mode = get_picture_settings()["settings"]["energySaving"]

    if current_mode in modes:
        next_mode = modes.index(current_mode) + 1
    else:  # It's probably in auto mode so just start at the first mode
        next_mode = 0

    if next_mode >= len(modes):
        next_mode = 0

    inputs["mode"] = modes[next_mode]
    set_energy_mode(inputs)


def toggle_eye_comfort(inputs):
    """Toggle the eye comfort mode aka reduce blue light"""
    current_mode = get_picture_settings()["settings"]["eyeComfortMode"]
    print("current eye comfort mode: current_mode %s" % current_mode)
    if current_mode == "off":
        new_mode = "on"
    else:
        new_mode = "off"
    endpoint = "luna://com.webos.settingsservice/setSystemSettings"
    payload = {"category": "picture", "settings": {"eyeComfortMode": new_mode}}
    luna_send(endpoint, payload)
    if inputs.get("notifications"):
        show_message("Reduce blue light mode: %s" % new_mode)


def screen_off(inputs):
    """Turns the screen off, but not the TV itself.
    Press any button but power and vol to turn it back on.
    """
    endpoint = "luna://com.webos.service.tvpower/power/turnOffScreen"
    payload = {}
    luna_send(endpoint, payload)


def set_energy_mode(inputs):
    """Sets the energy savings mode
    Inputs:
        - mode (string, default: none)
            - Valid values: min med max off auto screen_off
    Note screen_off may not work on some models, best to use the screen_off function instead
    """
    mode = inputs["mode"]
    endpoint = "luna://com.webos.settingsservice/setSystemSettings"
    payload = {"category": "picture", "settings": {"energySaving": mode}}
    luna_send(endpoint, payload)
    if inputs.get("notifications"):
        show_message("Energy mode: %s" % mode)


def increase_oled_light(inputs):
    """Increase the oled light value
    Inputs:
        increment (10) - the value to raise the light level on each press
        disable_energy_savings (True) - If energy savings is on, disable it
    """
    increment_oled_light(inputs, direction="up")


def reduce_oled_light(inputs):
    """Decrease the oled light value
    Inputs:
        increment (10) - the value to lower the light level on each press
        disable_energy_savings (True) - If energy savings is on, disable it
    """
    increment_oled_light(inputs, direction="down")


def set_oled_backlight(inputs):
    backlight = inputs["backlight"]
    endpoint = "luna://com.webos.settingsservice/setSystemSettings"
    payload = {"category": "picture", "settings": {"backlight": backlight}}
    luna_send(endpoint, payload)
    if inputs.get("notifications"):
        show_message("OLED Backlight: %s" % backlight)


def launch_app(inputs):
    """Launch an app by app_id
    Inputs:
        app_id - Use list_apps.py to get the app_id
        params (optional) - dict of launch params passed to the app.
            For the browser (com.webos.app.browser) use {"target": "https://..."}
            to open a specific URL.
    """
    app_id = inputs["app_id"]
    endpoint = "luna://com.webos.service.applicationmanager/launch"
    payload = {"id": app_id}
    params = inputs.get("params")
    if params:
        payload["params"] = params
    luna_send(endpoint, payload)


def send_ir_command(inputs):
    """Send an IR command to a configured device
    This relies on you using the device connection manager to setup your IR device (ie a soundbar)
    Once setup you can use this function to have the remote send IR commands
    """
    tv_input = inputs["tv_input"]  # "OPTICAL", other inputs untested
    keycode = inputs["keycode"]  # "IR_KEY_VOLUP" "IR_KEY_POWER"
    device_type = inputs["device_type"]  # "audio"

    endpoint = "luna://com.webos.service.irdbmanager/sendIrCommand"
    payload = {
        "keyCode": keycode,
        "buttonState": "single",
        "connectedInput": tv_input,
        "deviceType": device_type,
    }
    luna_send(endpoint, payload)


def curl(inputs):
    """Execute the system curl binary with the provided inputs
    Note this script has to work on Python 2.7 and 3.x, and very
    few Python libraries are included in WebOS, so we'll just
    keep it simple and use the system curl binary vs urllib.
    """

    url = inputs.get("url")
    if not url:
        print("ERROR: curl function called but url not supplied")
        return

    method = inputs.get("method", "GET").upper()

    command_string = "curl -vs -X %s" % method
    command = command_string.split()

    headers = inputs.get("headers")
    if headers:
        if type(headers) == list:
            for header in headers:
                command.append("-H")
                command.append(header)
        else:
            if type(headers) != str:  # Python 2.7 on the C9 returns unicode instead of str
                headers = str(headers)
            command.append("-H")
            command.append(headers)

    data = inputs.get("data")
    if data:
        command.append("-d")
        command.append(data)

    command.append(url)
    print("Running curl command: %s" % " ".join(command))

    try:
        output = subprocess.check_output(command)
    except subprocess.CalledProcessError as error:
        print("WARNING: curl command failed")
        print(error)
        return

    return output


def press_button(inputs):
    """Simulate a button press on the remote
    This is useful to simulate the play and pause buttons for remotes that don't have these buttons
    Inputs: button_name (str)
    """
    button = inputs["button"]
    keycode = get_keycode(button)
    if not keycode:
        return
    output_device_path = resolve_output_device()
    print("Simulating keystroke with button '%s' (keycode %s). Output device: %s" % (button, keycode, output_device_path))
    send_keystroke(output_device_path, keycode)


def send_cec_button(inputs):
    """This sends an HDMI-CEC button press to the current input device
    Consider this experimental, little is known about how this works (from my perspective as the developer)
    Inputs:
        code (integer, default: none) - The code to send.  Only code known at present is 18882561 which is "Home".
    """
    code = inputs["code"]
    if WEBOS_MAJOR_VERSION < 5:
        endpoint = "luna://com.webos.service.tv.keymanager/createKeyEvent"
        code_key = "code"
    else:
        endpoint = "luna://com.webos.service.eim/cec/sendKeyEvent"
        code_key = "key"

    payload = {code_key: code, "device": "remoteControl", "id": "magic_mapper", "type": "keyDown"}
    luna_send(endpoint, payload)
    payload["type"] = "keyUp"
    luna_send(endpoint, payload)


def set_dynamic_tone_mapping(inputs):
    """Set a specific value for Dynamic Tone Mapping
    Inputs:
        - value (string, default: none)
            - Valid values: "off", "on", "HGIG"
    """
    value = inputs["value"]

    # values are case sensitive
    if value.upper() == "HGIG":
        value = "HGIG"
    else:
        value = value.lower()

    endpoint = "luna://com.webos.settingsservice/setSystemSettings"
    payload = {"category": "picture", "settings": {"hdrDynamicToneMapping": value}}
    luna_send(endpoint, payload)

def disabled(inputs):
    print("Key was disabled")

def send_tcp_command(inputs):
    """Send a TCP command to a specified IP address and port.
    Inputs:
        ip (str): The IP address of the target device.
        port (int): The port number of the target device.
        command (str): The command string to send.
        timeout (float, optional): Socket timeout in seconds. Default is 5.
    """
    if not SOCKET_AVAILABLE:
        print("ERROR: socket library is not available, cannot use send_tcp_command()")
        return

    ip = inputs.get("ip")
    port = inputs.get("port")
    command = inputs.get("command")
    timeout = inputs.get("timeout", 5.0)

    if not ip or not port or command is None: # command can be an empty string
        print("ERROR: send_tcp_command called with missing ip, port, or command")
        return

    try:
        # Ensure command is a string and ends with a newline for many TCP services
        if not command.endswith("\r\n"):
            command += "\r\n"

        # Convert command to bytes
        command_bytes = command.encode('utf-8')

        print("Sending TCP command '%s' to %s:%s" % (command, ip, port))

        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        sock.settimeout(timeout)
        sock.connect((ip, port))
        sock.sendall(command_bytes)
        # Optionally, receive a response
        # response = sock.recv(1024)
        # print("Received response: %s" % response.decode('utf-8'))
        sock.close()
        print("TCP command sent successfully.")
    except socket.error as e:
        print("ERROR: Could not send TCP command to %s:%s - %s" % (ip, port, e))
    except Exception as e:
        print("ERROR: An unexpected error occurred in send_tcp_command: %s" % e)

def toggle_piccap(inputs):
    piccap_service = "luna://org.webosbrew.piccap.service"
    status = luna_send("%s/status" % piccap_service, {})
    status = json.loads(status)

    if status.get("isRunning"):
        action = "stopped"
        endpoint = "%s/stop" % piccap_service
    else:
        action = "started"
        endpoint = "%s/start" % piccap_service

    luna_send(endpoint, {})
    print("PicCap service %s" % action)


def toggle_bluetooth(inputs):
    """Toggle the WebOS bluetooth service on or off.

    Disabling bluetooth turns the Magic Remote into an IR-only remote (only the
    IR functions keep working), but stops unwanted bluetooth connection requests.
    This starts/stops the same webos-bluetooth-service that the webOS Bluetooth
    Disabler app controls; magic_mapper already runs as root so it can call the
    init system directly instead of going through the Homebrew Channel service.

    Inputs:
        notifications (bool, default: False) - show a toast with the new state
    """
    init_system = get_init_system()
    if not init_system:
        print("ERROR: could not determine init system, cannot toggle bluetooth")
        if inputs.get("notifications"):
            show_message("Bluetooth toggle failed")
        return

    active = bluetooth_is_active(init_system)

    if active:
        new_state = "off"
        if init_system == "systemd":
            command = ["systemctl", "stop", "webos-bluetooth-service.service"]
        else:
            command = ["stop", "webos-bluetooth-service"]
    else:
        new_state = "on"
        if init_system == "systemd":
            command = ["systemctl", "start", "webos-bluetooth-service.service"]
        else:
            command = ["start", "webos-bluetooth-service"]

    print("Bluetooth service is %s, turning it %s" % (
        "active" if active else "inactive", new_state))

    try:
        subprocess.check_call(command)
    except (subprocess.CalledProcessError, OSError) as error:
        print("WARNING: failed to toggle bluetooth: %s" % error)
        if inputs.get("notifications"):
            show_message("Bluetooth toggle failed")
        return

    print("Bluetooth turned %s" % new_state)
    if inputs.get("notifications"):
        show_message("Bluetooth: %s" % new_state)

###################################
# Private Functions
# The fuctions below here should not be called by magic_mapper_config.json
####################################

# The functions above that magic_mapper_config.json is allowed to call.
# If you add a new function for the config, add it here too.
CONFIG_FUNCTIONS = (
    "cycle_energy_mode",
    "toggle_eye_comfort",
    "screen_off",
    "set_energy_mode",
    "increase_oled_light",
    "reduce_oled_light",
    "set_oled_backlight",
    "launch_app",
    "send_ir_command",
    "curl",
    "press_button",
    "send_cec_button",
    "set_dynamic_tone_mapping",
    "disabled",
    "send_tcp_command",
    "toggle_piccap",
    "toggle_bluetooth",
)


def get_button_map():
    """Read the json config file"""
    config_path = os.path.join(os.path.dirname(__file__), "magic_mapper_config.json")
    with open(config_path) as config_file:
        button_map = json.load(config_file)
    settings = button_map.pop("magic_mapper_settings", {})
    apply_settings(settings)
    return validate_button_map(button_map)


def validate_button_map(button_map):
    """Check every button mapping at startup and drop the invalid ones so the rest still work"""
    valid_map = {}
    for button, actions in button_map.items():
        if actions == "disabled":
            valid_map[button] = actions
            continue
        if isinstance(actions, dict):
            action_list = [actions]
        elif isinstance(actions, list):
            action_list = actions
        else:
            print("ERROR: config for button '%s' must be a dict, a list of dicts, or \"disabled\", ignoring it" % button)
            continue

        problems = []
        for action in action_list:
            if not isinstance(action, dict):
                problems.append("each entry must be a dict")
            elif action.get("function") not in CONFIG_FUNCTIONS:
                problems.append("unknown function '%s'" % action.get("function"))
            elif not isinstance(action.get("inputs", {}), dict):
                problems.append("inputs for '%s' must be a dict" % action["function"])
        if not action_list:
            problems.append("the list of actions is empty")

        if problems:
            print("ERROR: config for button '%s' is invalid (%s), ignoring it" % (button, "; ".join(problems)))
            continue
        valid_map[button] = actions
    return valid_map


def apply_settings(settings):
    """Override the default settings with the magic_mapper_settings section of the config"""
    global BLOCK_MOUSE, EXCLUSIVE_MODE, INPUT_DEVICE_NAME, INPUT_DEVICE_NAME_SET, OUTPUT_DEVICE_NAME, OUTPUT_DEVICE_NAME_SET
    global IR_INPUT_ENABLED, IR_INPUT_DEVICE_NAME, IR_EXCLUSIVE_MODE
    for key in settings:
        if key not in ["block_mouse", "exclusive_mode", "input_device_name", "output_device_name",
                       "ir_input_enabled", "ir_input_device_name", "ir_exclusive_mode"]:
            print("WARNING: unknown setting '%s' in magic_mapper_settings" % key)

    if "block_mouse" in settings:
        BLOCK_MOUSE = str_to_bool(settings["block_mouse"])
    if "exclusive_mode" in settings:
        EXCLUSIVE_MODE = str_to_bool(settings["exclusive_mode"])
    if "input_device_name" in settings:
        INPUT_DEVICE_NAME = settings["input_device_name"]
        INPUT_DEVICE_NAME_SET = True
    if "output_device_name" in settings:
        OUTPUT_DEVICE_NAME = settings["output_device_name"]
        OUTPUT_DEVICE_NAME_SET = True
    if "ir_input_enabled" in settings:
        IR_INPUT_ENABLED = str_to_bool(settings["ir_input_enabled"])
    if "ir_input_device_name" in settings:
        IR_INPUT_DEVICE_NAME = settings["ir_input_device_name"]
    if "ir_exclusive_mode" in settings:
        IR_EXCLUSIVE_MODE = str_to_bool(settings["ir_exclusive_mode"])

    if BLOCK_MOUSE and not EXCLUSIVE_MODE:
        print("WARNING: block_mouse has no effect unless exclusive_mode is true")
    if "ir_exclusive_mode" in settings and IR_EXCLUSIVE_MODE and not IR_INPUT_ENABLED:
        print("WARNING: ir_exclusive_mode has no effect unless ir_input_enabled is true")


def fire_event_one(action):
    """Execute the function configured for the button"""
    func_name = action["function"]
    print("func_name: %s" % func_name)
    if func_name not in CONFIG_FUNCTIONS:
        print("ERROR: function '%s' can't be called from magic_mapper_config.json" % func_name)
        return
    inputs = action.get("inputs", {})
    globals()[func_name](inputs)

def fire_events(actions):
    """Execute the function(s) configured for the button"""
    for action in actions:
        fire_event_one(action)


def luna_send(endpoint, payload):
    # Execute luna send and return the output
    #
    # webOS 10.x (Rockhopper) regression: `luna-send -n 1` is a silent no-op --
    # it neither prints a response nor actually delivers the message, so every
    # bound button would appear to do nothing. Verified A/B on an OLED65C4PUA
    # (webOS 10.3.1): an identical launch call fires with `-t 1` and does nothing
    # with `-n 1`. `-t 1` delivers exactly once (it means "time 1 iteration"),
    # but the response payload comes back on STDERR behind a
    # "timingServiceResponse" line, so the callers that json.loads() this need it
    # recovered from there.
    #
    # Gated on version so pre-10 devices keep the exact original code path.
    if WEBOS_MAJOR_VERSION >= 10:
        command = ["/usr/bin/luna-send", "-t", "1", endpoint, json.dumps(payload)]
        print("running command: %s" % command)
        proc = subprocess.run(command, capture_output=True)
        for line in proc.stderr.decode("utf-8", "replace").splitlines():
            if "timingServiceResponse" in line and "{" in line:
                return line[line.find("{"):]
        return proc.stdout.decode("utf-8", "replace")

    command = ["/usr/bin/luna-send", "-n", "1"]
    command.append(endpoint)
    command.append(json.dumps(payload))
    print("running command: %s" % command)
    output = subprocess.check_output(command)
    return output


def increment_oled_light(inputs, direction):
    """Increment the oled backlight up or down"""
    increment = inputs.get("increment", 10)

    current_settings = get_picture_settings()["settings"]

    disable_energy_savings = str_to_bool(inputs.get("disable_energy_savings", True))
    if disable_energy_savings:
        if current_settings["energySaving"] != "off":
            set_energy_mode({"mode": "off"})

    current_value = int(current_settings["backlight"])

    if direction == "up":
        new_value = current_value + increment
        if new_value > 100:
            new_value = 100
    elif direction == "down":
        new_value = current_value - increment
        if new_value < 0:
            new_value = 0

    inputs["backlight"] = new_value
    set_oled_backlight(inputs)


def get_picture_settings():
    # Return the current settings
    endpoint = "luna://com.webos.settingsservice/getSystemSettings"
    payload = {"category": "picture"}
    output = luna_send(endpoint, payload)
    settings = json.loads(output)
    return settings


def show_message(message):
    """Shows a "toast" message"""
    endpoint = "luna://com.webos.notification/createToast"
    payload = {"message": message}
    luna_send(endpoint, payload)


def get_keycode(button):
    """Returns the keycode associated with the button name"""
    keys = [k for k, v in BUTTONS.items() if v == button]
    if keys:
        return keys[0]

    print('ERROR: Button "%s" not found!' % button)
    return None


def send_keystroke(device, keycode):
    """Send a keystroke to the input device
        We use this to simulate button presses like play/pause since those require special handling
        Use the press_button function for magic_mapper_config.json
    };
    """
    send_input_event(device, keycode, 1, 1)
    send_input_event(device, 0, 0, 0)
    send_input_event(device, keycode, 0, 1)
    send_input_event(device, 0, 0, 0)


def send_input_event(device, keycode, value, event_type):
    """Low level function to write to the input device file
    Don't call this from magic_mapper_config.json
    """
    input_format = "llHHI"

    out_file = os.open(device, os.O_RDWR)
    now = time.time()
    tv_sec = int(now)
    tv_usec = int((now - tv_sec) * 1000000)

    data = [tv_sec, tv_usec, event_type, keycode, value]
    # print("writing: %s" % data)

    event = struct.pack(input_format, *data)
    os.write(out_file, event)
    os.close(out_file)


def str_to_bool(value):
    """Convert a config value to bool. Accepts bools and strings."""
    if isinstance(value, bool):
        return value
    if str(value).lower() in ["yes", "true"]:
        return True
    return False


def get_webos_version():
    """Return webos version"""
    try:
        with open("/etc/starfish-release") as f:
            release = f.read()

        version = release.split()[2]
        major_version = version.split(".")[0]
        return int(major_version)
    except (OSError, IOError, IndexError, ValueError) as e:
        print("WARNING: could not determine the WebOS version, assuming an old version: %s" % e)
        return 0


def get_init_system():
    """Detect whether the TV uses systemd or upstart.

    On systemd TVs /sbin/init is a symlink to systemd. Upstart TVs have a plain
    /sbin/init, so look for upstart's initctl instead.
    Returns "systemd", "upstart", or None if unknown.
    """
    if "systemd" in os.path.realpath("/sbin/init"):
        return "systemd"
    if os.path.exists("/sbin/initctl"):
        return "upstart"
    print("WARNING: could not determine the init system")
    return None


def bluetooth_is_active(init_system):
    """Return True if the webos-bluetooth-service is currently running."""
    if init_system == "systemd":
        # `systemctl is-active` prints "active" and exits 0 when running, or
        # prints "inactive"/"failed" and exits non-zero when not.
        try:
            output = subprocess.check_output(
                ["systemctl", "is-active", "webos-bluetooth-service.service"])
        except subprocess.CalledProcessError as error:
            output = error.output or b""
        except OSError as error:
            print("WARNING: could not query bluetooth status: %s" % error)
            return False
        return output.decode("utf-8", "replace").strip() == "active"

    # upstart: `status webos-bluetooth-service` prints "... start/running"
    # when up and "... stop/waiting" when down.
    try:
        output = subprocess.check_output(["status", "webos-bluetooth-service"])
    except (subprocess.CalledProcessError, OSError) as error:
        print("WARNING: could not query bluetooth status: %s" % error)
        return False
    return "start/running" in output.decode("utf-8", "replace")


def open_source_device(device_name, grab):
    """Resolve, open, and (optionally) grab an input device.

    Returns a dict describing the source, or None if it could not be opened.
    The device is opened unbuffered (os.open/os.read): a buffered file would
    pull several events into Python's buffer where select() can't see them,
    delaying key ups until the next press.
    """
    path = resolve_input_device_by_name(device_name)
    if not path:
        print("WARNING: could not resolve input device '%s'" % device_name)
        return None

    try:
        fd = os.open(path, os.O_RDONLY)
    except (IOError, OSError) as error:
        print("WARNING: could not open input device '%s' (%s): %s" % (device_name, path, error))
        return None

    grabbed = False
    if grab:
        try:
            fcntl.ioctl(fd, EVIOCGRAB, 1)
            grabbed = True
            print("Exclusive mode: grabbed input device '%s' (%s)" % (device_name, path))
        except (IOError, OSError) as error:
            print("WARNING: could not grab '%s' (%s): %s" % (device_name, path, error))

    print("Opened input device '%s' (%s)" % (device_name, path))
    return {"name": device_name, "path": path, "fd": fd, "grabbed": grabbed}


def open_output_device():
    """Open the device unmapped events are resent to in exclusive mode, or return None"""
    output_device_path = resolve_output_device()
    if output_device_path is None:
        return None
    try:
        output_device = os.open(output_device_path, os.O_WRONLY)
    except (IOError, OSError) as error:
        print("WARNING: could not open output device %s: %s" % (output_device_path, error))
        return None
    print("Keys will be resent to: %s" % output_device_path)
    return output_device


def resend_event(output, event):
    """Resend an unmapped event to the output device, reopening the device once if the write fails"""
    if output["fd"] is not None:
        try:
            os.write(output["fd"], event)
            return
        except (IOError, OSError) as error:
            print("WARNING: could not resend event to the output device, reopening it: %s" % error)
            try:
                os.close(output["fd"])
            except (IOError, OSError):
                pass
    output["fd"] = open_output_device()
    if output["fd"] is None:
        print("ERROR: no output device, dropping event")
        return
    try:
        os.write(output["fd"], event)
    except (IOError, OSError) as error:
        print("ERROR: could not resend event to the output device, dropping it: %s" % error)


def input_loop(button_map):
    # Read from the input device(s)
    # https://stackoverflow.com/a/16682549/866057
    input_format = "llHHi"
    event_size = struct.calcsize(input_format)
    buttons_waiting = {}

    # (device name, grab) for every device we read: the remote over bluetooth,
    # and if ir_input_enabled is true the IR receiver, which gets the remote's
    # presses while bluetooth is off
    wanted = [(INPUT_DEVICE_NAME, EXCLUSIVE_MODE)]
    if IR_INPUT_ENABLED:
        if not SELECT_AVAILABLE:
            print("WARNING: the select library isn't available, IR input is disabled")
        elif IR_INPUT_DEVICE_NAME == INPUT_DEVICE_NAME:
            print("ir_input_device_name is the same as input_device_name, not reading it twice")
        else:
            wanted.append((IR_INPUT_DEVICE_NAME, IR_EXCLUSIVE_MODE))

    output = {"fd": None}
    if [name for name, grab in wanted if grab]:
        print("Exclusive mode is enabled, taking over input device(s)")
        output["fd"] = open_output_device()
        if output["fd"] is None:
            # Carry on without exclusive mode rather than exiting, so the buttons still work
            print("ERROR: could not find output device, check output_device_name in magic_mapper_config.json. Continuing without exclusive mode")
            wanted = [(name, False) for name, grab in wanted]
    else:
        print("EXCLUSIVE_MODE is disabled, will not override default button behavior")

    sources = {}  # fd -> source dict from open_source_device()
    for name, grab in wanted:
        source = open_source_device(name, grab)
        if source:
            sources[source["fd"]] = source
    if not sources:
        print("ERROR: could not find input device, check input_device_name in magic_mapper_config.json")
        sys.exit(1)

    first_loop = 2
    while True:

        if first_loop == 1:
            print("First loop complete, Magic Mapper is running")
            first_loop = 0
        elif first_loop == 2:
            print("Input loop started, waiting for button presses on %d device(s)" % len(sources))
            first_loop = 1

        if SELECT_AVAILABLE:
            readable = select.select(list(sources), [], [])[0]
        else:
            readable = list(sources)  # only one device without select, a blocking read is fine

        for fd in readable:
            source = sources[fd]
            try:
                event = os.read(fd, event_size)
            except (IOError, OSError) as error:
                event = None
                print("WARNING: could not read input device '%s': %s" % (source["name"], error))
            if not event:
                # Exit so start_magic_mapper restarts us and reopens the devices
                print("ERROR: lost input device '%s', exiting" % source["name"])
                sys.exit(1)
            handle_event(event, input_format, source, button_map, buttons_waiting, output)


def handle_event(event, input_format, source, button_map, buttons_waiting, output):
    """Process a single input event read from one of the source devices."""
    (tv_sec, tv_usec, event_type, code, value) = struct.unpack(input_format, event)

    now = time.time()
    key = None
    if event_type == 1:
        key = BUTTONS.get(code)
    elif event_type == 2:
        code = value  # up/down
        key = MOUSE_WHEEL.get(code)
        value = 0
        buttons_waiting[(source["name"], code)] = now

    actions = button_map.get(key)
    if actions == "disabled":
        print("Button %s is disabled" % key)
        return

    current_app = None
    if actions:
        if type(actions) is not list:
            actions = [actions]
        endpoint = "luna://com.webos.applicationManager/getForegroundAppInfo"
        try:
            current_app = json.loads(luna_send(endpoint, {})).get('appId')
        except Exception:
            print("ERROR: could not get the foreground app, only mappings without an appId will be used")
            traceback.print_exc()
        filtered_actions = []
        found_match = False
        for action in actions:
            appId = action.get('appId')
            if appId is None:
                filtered_actions += [action]
            if appId == current_app:
                filtered_actions += [action]
                found_match = True
            if appId == '!' and not found_match:
                filtered_actions += [action]
        actions = filtered_actions

    if not actions:
        # In exclusive mode we resend unhandled events so others can read them.
        # Only grabbed devices need this, ungrabbed devices already deliver their events normally.
        if source["grabbed"] and not (BLOCK_MOUSE and code == 1198):
            resend_event(output, event)
        if key and value == 1:
            print("Button %s not configured in magic_mapper_config.json (device: %s, code: %s)" % (key, source["name"], code))
        elif value == 1:
            print("Button code %s ignored (device: %s)" % (code, source["name"]))
        return

    wait_key = (source["name"], code)

    # Button Down
    if value == 1:
        print("%s button down (device: %s)" % (key, source["name"]))
        if wait_key in buttons_waiting and now - buttons_waiting[wait_key] < 1.0:
            print("WARNING: Got code %s DOWN while waiting for UP" % code)
        buttons_waiting[wait_key] = now

    # Button Up
    if value == 0:
        if wait_key not in buttons_waiting:
            print("WARNING: Got code %s UP with no DOWN" % code)
        elif now - buttons_waiting[wait_key] > 1.0:
            print("Ignoring long press of %s" % key)
            # Tell the user that the long press was blocked because of magic mapper; to avoid any confusion.
            try:
                luna_send("luna://com.webos.notification/createToast", {"sourceId":"magic mapper","message":"long press for %s is disabled due to magic mapper" % key})
            except Exception:
                traceback.print_exc()
        else:
            print("%s button up (device: %s)" % (key, source["name"]))
            print("firing event(s) for code: %s button: %s" % (code, key))
            # Don't let one failing action kill the script
            try:
                fire_events(actions)
            except Exception:
                print("ERROR: action for button %s failed" % key)
                traceback.print_exc()
        if wait_key in buttons_waiting:
            del buttons_waiting[wait_key]


def read_input_devices():
    """
    Parse /proc/bus/input/devices into a list of (name, event_path) tuples
    """
    try:
        with open("/proc/bus/input/devices", "r") as f:
            data = f.read()
    except Exception as e:
        print("ERROR: cannot read /proc/bus/input/devices: %s" % e)
        return []

    devices = []
    # Split before each I: line; each block describes one device.
    # The pattern must consume the newline: re.split ignores zero-width matches before python 3.7
    blocks = re.split(r"\n\s*(?=I:)", data.strip())
    for block in blocks:
        # Look for N: Name="..."
        m_name = re.search(r'^N:\s+Name="([^"]+)"', block, flags=re.M)
        if not m_name:
            continue

        # Look for H: Handlers=... and pick the first 'eventX'
        event_path = None
        m_handlers = re.search(r'^H:\s+Handlers=([^\n]+)', block, flags=re.M)
        if m_handlers:
            for h in m_handlers.group(1).split():
                if h.startswith("event") and h[5:].isdigit():
                    event_path = "/dev/input/" + h
                    break
        devices.append((m_name.group(1), event_path))
    return devices


def resolve_input_device_by_name(device_name, quiet=False):
    """
    Find the input device path by looking for the device_name in /proc/bus/input/devices
    quiet=True skips the warning when the device isn't found
    """
    print("Resolving input device path for device named '%s'" % device_name)
    devices = read_input_devices()
    for name, event_path in devices:
        if name == device_name and event_path:
            print("Resolved '%s' to %s" % (device_name, event_path))
            return event_path

    if quiet:
        print("Device named '%s' not found" % device_name)
        return None
    print("WARNING: device named '%s' not found in /proc/bus/input/devices" % device_name)
    print("Available devices: %s" % ", ".join("'%s'" % name for name, _ in devices))
    return None


def resolve_output_device():
    """
    Find the device to resend unbound codes to. On webOS 10+ prefer WEBOS_10_OUTPUT_DEVICE_NAME
    unless output_device_name was set. Then use OUTPUT_DEVICE_NAME if it exists,
    otherwise fall back to any other 'LGE M-RCU - Builtin [N]' device that isn't INPUT_DEVICE_NAME
    """
    if not OUTPUT_DEVICE_NAME_SET and WEBOS_MAJOR_VERSION >= 10 and WEBOS_10_OUTPUT_DEVICE_NAME != INPUT_DEVICE_NAME:
        output_device_path = resolve_input_device_by_name(WEBOS_10_OUTPUT_DEVICE_NAME, quiet=True)
        if output_device_path:
            print("Using '%s' as the output device on webOS 10+" % WEBOS_10_OUTPUT_DEVICE_NAME)
            return output_device_path

    # The default OUTPUT_DEVICE_NAME is often missing, only warn if it was set in the config
    output_device_path = resolve_input_device_by_name(OUTPUT_DEVICE_NAME, quiet=not OUTPUT_DEVICE_NAME_SET)
    if output_device_path:
        return output_device_path

    for name, event_path in read_input_devices():
        if name.startswith("LGE M-RCU - Builtin") and name != INPUT_DEVICE_NAME and event_path:
            print("Falling back to output device '%s' (%s)" % (name, event_path))
            return event_path
    return None


def main():
    """MAIN"""
    print("Starting Magic Mapper %s" % VERSION)
    time.sleep(2) # Ensure everything is running before we start
    button_map = get_button_map()

    global WEBOS_MAJOR_VERSION
    WEBOS_MAJOR_VERSION = get_webos_version()
    print("WEBOS_MAJOR_VERSION: %s" % WEBOS_MAJOR_VERSION)

    print("Settings:")
    print("  block_mouse: %s" % BLOCK_MOUSE)
    print("  exclusive_mode: %s" % EXCLUSIVE_MODE)
    print("  input_device_name: '%s'%s" % (INPUT_DEVICE_NAME, "" if INPUT_DEVICE_NAME_SET else " (default)"))
    print("  output_device_name: '%s'" % (OUTPUT_DEVICE_NAME if OUTPUT_DEVICE_NAME_SET else "auto"))
    print("  ir_input_enabled: %s" % IR_INPUT_ENABLED)
    print("  ir_input_device_name: '%s'" % IR_INPUT_DEVICE_NAME)
    print("  ir_exclusive_mode: %s" % IR_EXCLUSIVE_MODE)

    input_loop(button_map=button_map)


if __name__ == "__main__":
    main()