#!/usr/bin/env python3
import sys
import os
import time

# Change path so we find Xlib
sys.path.append(os.path.join(os.path.dirname(__file__), '..'))

from Xlib.display import Display
from Xlib.ext import xinerama, xinput, xfixes
from Xlib.protocol import rq

xfixes_extname = 'XFIXES'

BarrierPositiveX = (1 << 0)
BarrierPositiveY = (1 << 1)
BarrierNegativeX = (1 << 2)
BarrierNegativeY = (1 << 3)

class CreatePointerBarrier(rq.Request):
    _request = rq.Struct(rq.Card8('opcode'),
                         rq.Opcode(31),
                         rq.RequestLength(),
                         rq.Resource('barrier'),
                         rq.Window('window'),
                         rq.Int16('x1'),
                         rq.Int16('y1'),
                         rq.Int16('x2'),
                         rq.Int16('y2'),
                         rq.Card32('directions'),
                         rq.Pad(2),
                         rq.LengthOf('devices', 2),
                         rq.List('devices', xinput.DEVICEID),
                         )

def create_pointer_barrier(self, x1, y1, x2, y2, barrier_directions, devices=None):
    barrier = self.display.allocate_resource_id()
    CreatePointerBarrier(
            display=self.display,
            opcode=self.display.get_extension_major(xfixes_extname),
            window=self,
            x1=x1,
            y1=y1,
            x2=x2,
            y2=y2,
            directions=barrier_directions,
            devices=[] if not devices else devices,
            barrier=barrier)
    return barrier

def main(argv):
    display = Display()
    screen = display.screen()
    window = screen.root


    def check_extension(name):
        if not display.has_extension(name):
            sys.stderr.write('%s: server does not have the %s extension\n' % (sys.argv[0], name))
            ext = display.query_extension(name)
            print(ext)
            sys.stderr.write("\n".join(display.list_extensions()))
            if ext is None:
                sys.exit(1)

    check_extension('XFIXES')
    check_extension('XInputExtension')
    check_extension('XINERAMA')

    xfixes_version = xfixes.QueryVersion(display=window.display, opcode=window.display.get_extension_major(xfixes_extname), major_version=5, minor_version=0)
    print('Found XFIXES version %s.%s' % (
      xfixes_version.major_version,
      xfixes_version.minor_version,
    ), file=sys.stderr)

    xinput_version = display.xinput_query_version()
    print('Found XInputExtension version %s.%s' % (
      xinput_version.major_version,
      xinput_version.minor_version,
    ), file=sys.stderr)

    xinerama_version = display.xinerama_query_version()
    print('Found XINERAMA version %s.%s' % (
      xinerama_version.major_version,
      xinerama_version.minor_version,
    ), file=sys.stderr)

    print()
    print('Available screens:')
    screens = xinerama.query_screens(window).screens
    for (idx, screen) in enumerate(screens):
        x, y, w, h = screen.x, screen.y, screen.width, screen.height
        print('screen %d: %s' % (idx, screen))

    print()
    print('Available pointers:')
    pointer_name = {}
    devices = xinput.query_device(window, xinput.AllMasterDevices).devices
    for device in devices:
        if 'pointer' in device.name:
            pointer_name[device.deviceid] = 'device %d: %s' % (device.deviceid, device.name)
            print(pointer_name[device.deviceid])

    if len(sys.argv) != 3:
        print()
        print('USAGE: %s [device] [screen]' % (sys.argv[0]))
        return -2
    lock_device = int(sys.argv[1])
    lock_screen = int(sys.argv[2])

    screen = screens[lock_screen]

    print()
    print('Creating barrier to force pointer %s to screen %d (%s)...' %\
            (pointer_name[lock_device], lock_screen, screens[lock_screen]))
    top = screen.y + 3
    bottom = screen.y + screen.height - 3
    left = screen.x + 1
    right = screen.x + screen.width - 1
    print('Barrier bounds: left=%d, top=%d, right=%d, bottom=%d' % (left, top, right, bottom))
    # top
    create_pointer_barrier(window, left, top, right, top, BarrierPositiveY, [lock_device])
    # left
    create_pointer_barrier(window, left, top, left, bottom, BarrierPositiveX, [lock_device])
    # bottom
    create_pointer_barrier(window, left, bottom, right, bottom, BarrierNegativeY, [lock_device])
    # right
    create_pointer_barrier(window, right, top, right, bottom, BarrierNegativeX, [lock_device])
    display.sync()
    print('Created barrier.')
    input()

if __name__ == '__main__':
    sys.exit(main(sys.argv))