#! /usr/libexec/platform-python

# vim: set expandtab shiftwidth=4:

# -*- Mode: python; coding: utf-8; indent-tabs-mode: nil -*- */

#

# Copyright © 2017 Red Hat, Inc.

#

# Permission is hereby granted, free of charge, to any person obtaining a

# copy of this software and associated documentation files (the "Software"),

# to deal in the Software without restriction, including without limitation

# the rights to use, copy, modify, merge, publish, distribute, sublicense,

# and/or sell copies of the Software, and to permit persons to whom the

# Software is furnished to do so, subject to the following conditions:

#

# The above copyright notice and this permission notice (including the next

# paragraph) shall be included in all copies or substantial portions of the

# Software.

#

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL

# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER

# DEALINGS IN THE SOFTWARE.

#

import sys

import subprocess

import argparse

try:

    import evdev

    import evdev.ecodes

    import pyudev

except ModuleNotFoundError as e:

    print('Error: {}'.format(str(e)), file=sys.stderr)

    print('One or more python modules are missing. Please install those '

          'modules and re-run this tool.')

    sys.exit(1)

class Range(object):

    """Class to keep a min/max of a value around"""

    def __init__(self):

        self.min = float('inf')

        self.max = float('-inf')

    def update(self, value):

        self.min = min(self.min, value)

        self.max = max(self.max, value)

class Touch(object):

    """A single data point of a sequence (i.e. one event frame)"""

    def __init__(self, major=None, minor=None, orientation=None):

        self._major = major

        self._minor = minor

        self._orientation = orientation

        self.dirty = False

    @property

    def major(self):

        return self._major

    @major.setter

    def major(self, major):

        self._major = major

        self.dirty = True

    @property

    def minor(self):

        return self._minor

    @minor.setter

    def minor(self, minor):

        self._minor = minor

        self.dirty = True

    @property

    def orientation(self):

        return self._orientation

    @orientation.setter

    def orientation(self, orientation):

        self._orientation = orientation

        self.dirty = True

    def __str__(self):

        s = "Touch: major {:3d}".format(self.major)

        if self.minor is not None:

                s += ", minor {:3d}".format(self.minor)

        if self.orientation is not None:

                s += ", orientation {:+3d}".format(self.orientation)

        return s

class TouchSequence(object):

    """A touch sequence from beginning to end"""

    def __init__(self, device, tracking_id):

        self.device = device

        self.tracking_id = tracking_id

        self.points = []

        self.is_active = True

        self.is_down = False

        self.was_down = False

        self.is_palm = False

        self.was_palm = False

        self.is_thumb = False

        self.was_thumb = False

        self.major_range = Range()

        self.minor_range = Range()

    def append(self, touch):

        """Add a Touch to the sequence"""

        self.points.append(touch)

        self.major_range.update(touch.major)

        self.minor_range.update(touch.minor)

        if touch.major < self.device.up or \

           touch.minor < self.device.up:

                self.is_down = False

        elif touch.major > self.device.down or \

                touch.minor > self.device.down:

            self.is_down = True

            self.was_down = True

        self.is_palm = touch.major > self.device.palm

        if self.is_palm:

                self.was_palm = True

        self.is_thumb = self.device.thumb != 0 and touch.major > self.device.thumb

        if self.is_thumb:

            self.was_thumb = True

    def finalize(self):

        """Mark the TouchSequence as complete (finger is up)"""

        self.is_active = False

    def __str__(self):

        return self._str_state() if self.is_active else self._str_summary()

    def _str_summary(self):

        if not self.points:

            return "{:78s}".format("Sequence: no major/minor values recorded")

        s = "Sequence: major: [{:3d}..{:3d}] ".format(

                self.major_range.min, self.major_range.max

        )

        if self.device.has_minor:

                s += "minor: [{:3d}..{:3d}] ".format(

                        self.minor_range.min, self.minor_range.max

                     )

        if self.was_down:

                s += " down"

        if self.was_palm:

                s += " palm"

        if self.was_thumb:

            s += " thumb"

        return s

    def _str_state(self):

        touch = self.points[-1]

        s = "{}, tags: {} {} {}".format(

                                touch,

                                "down" if self.is_down else "    ",

                                "palm" if self.is_palm else "    ",

                                "thumb" if self.is_thumb else "     "

                                )

        return s

class InvalidDeviceError(Exception):

    pass

class Device(object):

    def __init__(self, path):

        if path is None:

            self.path = self.find_touch_device()

        else:

            self.path = path

        self.device = evdev.InputDevice(self.path)

        print("Using {}: {}\n".format(self.device.name, self.path))

        # capabilities returns a dict with the EV_* codes as key,

        # each of which is a list of tuples of (code, AbsInfo)

        #

        # Get the abs list first (or empty list if missing),

        # then extract the touch major absinfo from that

        caps = self.device.capabilities(absinfo=True).get(

                evdev.ecodes.EV_ABS, []

               )

        codes = [cap[0] for cap in caps]

        if evdev.ecodes.ABS_MT_TOUCH_MAJOR not in codes:

            raise InvalidDeviceError("Device does not have ABS_MT_TOUCH_MAJOR")

        self.has_minor = evdev.ecodes.ABS_MT_TOUCH_MINOR in codes

        self.has_orientation = evdev.ecodes.ABS_MT_ORIENTATION in codes

        self.up = 0

        self.down = 0

        self.palm = 0

        self.thumb = 0

        self._init_thresholds_from_quirks()

        self.sequences = []

        self.touch = Touch(0, 0)

    def find_touch_device(self):

        context = pyudev.Context()

        for device in context.list_devices(subsystem='input'):

            if not device.get('ID_INPUT_TOUCHPAD', 0) and \

               not device.get('ID_INPUT_TOUCHSCREEN', 0):

                continue

            if not device.device_node or \

                    not device.device_node.startswith('/dev/input/event'):

                continue

            return device.device_node

        print("Unable to find a touch device.", file=sys.stderr)

        sys.exit(1)

    def _init_thresholds_from_quirks(self):

        command = ['libinput', 'quirks', 'list', self.path]

        cmd = subprocess.run(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)

        if cmd.returncode != 0:

            print("Error querying quirks: {}".format(cmd.stderr.decode('utf-8')), file=sys.stderr)

            return

        stdout = cmd.stdout.decode('utf-8')

        quirks = [q.split('=') for q in stdout.split('\n')]

        for q in quirks:

            if q[0] == 'AttrPalmSizeThreshold':

                self.palm = int(q[1])

            elif q[0] == 'AttrTouchSizeRange':

                self.down, self.up = colon_tuple(q[1])

            elif q[0] == 'AttrThumbSizeThreshold':

                self.thumb = int(q[1])

    def start_new_sequence(self, tracking_id):

        self.sequences.append(TouchSequence(self, tracking_id))

    def current_sequence(self):

        return self.sequences[-1]

    def handle_key(self, event):

        tapcodes = [evdev.ecodes.BTN_TOOL_DOUBLETAP,

                    evdev.ecodes.BTN_TOOL_TRIPLETAP,

                    evdev.ecodes.BTN_TOOL_QUADTAP,

                    evdev.ecodes.BTN_TOOL_QUINTTAP]

        if event.code in tapcodes and event.value > 0:

                print("\rThis tool cannot handle multiple fingers, "

                      "output will be invalid", file=sys.stderr)

    def handle_abs(self, event):

        if event.code == evdev.ecodes.ABS_MT_TRACKING_ID:

                if event.value > -1:

                    self.start_new_sequence(event.value)

                else:

                    try:

                        s = self.current_sequence()

                        s.finalize()

                        print("\r{}".format(s))

                    except IndexError:

                        # If the finger was down during start

                        pass

        elif event.code == evdev.ecodes.ABS_MT_TOUCH_MAJOR:

                self.touch.major = event.value

        elif event.code == evdev.ecodes.ABS_MT_TOUCH_MINOR:

                self.touch.minor = event.value

        elif event.code == evdev.ecodes.ABS_MT_ORIENTATION:

                self.touch.orientation = event.value

    def handle_syn(self, event):

        if self.touch.dirty:

            try:

                self.current_sequence().append(self.touch)

                print("\r{}".format(self.current_sequence()), end="")

                self.touch = Touch(major=self.touch.major,

                                   minor=self.touch.minor,

                                   orientation=self.touch.orientation)

            except IndexError:

                pass

    def handle_event(self, event):

        if event.type == evdev.ecodes.EV_ABS:

            self.handle_abs(event)

        elif event.type == evdev.ecodes.EV_KEY:

            self.handle_key(event)

        elif event.type == evdev.ecodes.EV_SYN:

            self.handle_syn(event)

    def read_events(self):

        print("Ready for recording data.")

        print("Touch sizes used: {}:{}".format(self.down, self.up))

        print("Palm size used: {}".format(self.palm))

        print("Thumb size used: {}".format(self.thumb))

        print("Place a single finger on the device to measure touch size.\n"

              "Ctrl+C to exit\n")

        for event in self.device.read_loop():

            self.handle_event(event)

def colon_tuple(string):

    try:

        ts = string.split(':')

        t = tuple([int(x) for x in ts])

        if len(t) == 2 and t[0] >= t[1]:

            return t

    except:

        pass

    msg = "{} is not in format N:M (N >= M)".format(string)

    raise argparse.ArgumentTypeError(msg)

def main(args):

    parser = argparse.ArgumentParser(

            description="Measure touch size and orientation"

    )

    parser.add_argument('path', metavar='/dev/input/event0',

                        nargs='?', type=str, help='Path to device (optional)')

    parser.add_argument('--touch-thresholds', metavar='down:up',

                        type=colon_tuple,

                        help='Thresholds when a touch is logically down or up')

    parser.add_argument('--palm-threshold', metavar='t',

                        type=int, help='Threshold when a touch is a palm')

    args = parser.parse_args()

    try:

        device = Device(args.path)

        if args.touch_thresholds is not None:

            device.down, device.up = args.touch_thresholds

        if args.palm_threshold is not None:

            device.palm = args.palm_threshold

        device.read_events()

    except KeyboardInterrupt:

        pass

    except (PermissionError, OSError):

        print("Error: failed to open device")

    except InvalidDeviceError as e:

        print("This device does not have the capabilities for size-based touch detection.");

        print("Details: {}".format(e))

if __name__ == "__main__":

    main(sys.argv)