'''
HOW TO USE:
1) Set up QMP via telnet (e.g. -qmp tcp:localhost:4444,server,nowait)
2) Set target address (usualy localhost) and target port (must be same with you QMP config string)
3) Assign this script to any hotkey.
???
PROFIT!
'''

target_addr = 'localhost'
target_port = 4444

#target_addr = '192.168.1.1'
#target_port = 23

#Set productID in add strings. Get it by converting lsusb IDs to dec.
cmd_add_kbd = b'{ "execute": "device_add", "arguments": { "driver": "usb-host","productid": "257","id": "kbd" }}\n'
cmd_add_mouse = b'{ "execute": "device_add", "arguments": { "driver": "usb-host","productid": "49740","id": "mouse" }}\n'
cmd_del_kbd = b'{ "execute": "device_del", "arguments": { "id": "kbd" }}\n'
cmd_del_mouse = b'{ "execute": "device_del", "arguments": { "id": "mouse" }}\n'

import telnetlib

error_list = {
    0: "[ERR] Telnet sucessfully connected and got no valid QMP response. Wrong server?",
    1: "[ERR] Wrong QMP response. Version mismatch?.",
    2: "[ERR] Telnet connection failed. Check server address, port and server status.",
}

def telnet_reader(tn):
    data=' '
    while (('\n' not in data) and ('ogin' not in data)):
        data = tn.read_very_eager().decode('ascii')
#    print(data) #debug
    return(data)

def vm_checker ():
    tn = telnetlib.Telnet()
    try:
        tn.open(target_addr,target_port)
    except:
        return(2)
    else:
        if '"QMP"' not in telnet_reader(tn):
            tn.close()
            return(0)
        tn.write(b'{ "execute": "qmp_capabilities" }\n')
        if '"return"' not in telnet_reader(tn):
            tn.close()
            return(1)
        return(tn)

def vm_push_command (qmp_cmd,tn):
    tn.write(qmp_cmd)
    return(telnet_reader(tn))


if __name__ == '__main__':
    print('QMP virtual KVM-switch started.')
    tn = vm_checker()
    if type(tn) is int:
        print(error_list.get(tn))
    else:
        if '"Duplicate ID' in vm_push_command(cmd_add_mouse,tn):
            print('Mouse allready in VM, will delete it.')
            vm_push_command(cmd_del_mouse,tn)
            telnet_reader(tn)
        if '"Duplicate ID' in vm_push_command(cmd_add_kbd,tn):
            print('KBD allready in VM, will delete it.')
            vm_push_command(cmd_del_kbd,tn)
            telnet_reader(tn)
        tn.close()
    print('Done.')