import subprocess

class EnclosureCapabilities():
    """
    we want to know about any keyboards, 
    mice, and screens attached to the system.

    Usage:
        hardware_capabilities = EnclosureCapabilities()
        print("Kbds:%s" % (hardware_capabilities.keyboards,))
        print("Mice:%s" % (hardware_capabilities.mice,))
        print("Screens:%s" % (hardware_capabilities.screens,))

    Example Mark2 Output with mouse and keyboard plugged in:
        (.venv) mycroft@localhost:~$ python hdw_test.py
        Kbds:[{'name': 'Lite-On Technology Corp. USB Multimedia Keyboard', 'extra': ''}]
        Mice:[{'name': 'PIXART USB OPTICAL MOUSE', 'extra': ''}, {'name': 'FT5406 memory based driver', 'extra': 'Touch Screen'}]
        Screens:[{'name': 'DRM emulated', 'resolution': '800,480', 'pel_size': '32', 'extra': ''}]

    Example Mark2 Output with nothing plugged in.
        (.venv) mycroft@localhost:~$ python hdw_test.py
        Kbds:[]
        Mice:[{'name': 'FT5406 memory based driver', 'extra': 'Touch Screen'}]
        Screens:[{'name': 'DRM emulated', 'resolution': '800,480', 'pel_size': '32', 'extra': ''}]

    """
    name_line = 'N: Name="'
    keyboard_line = 'H: Handlers=sysrq kbd'
    mouse_line = 'H: Handlers=mouse'

    def __init__(self):
        self.mice = []
        self.keyboards = []
        self.screens = []

        self.caps = self._get_capabilities()

        self.mice = self.caps['mice']
        self.keyboards = self.caps['keyboards']
        self.screens = self.caps['screens']

    def execute_cmd(self, cmd):
        process = subprocess.Popen(
            cmd,
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
        )

        out, err = process.communicate()

        try:
            out = out.decode('utf8')
        except:
            pass

        try:
            err = err.decode('utf8')
        except:
            pass

        return out, err


    def _get_capabilities(self):
        # query input devices

        cmd = ["cat", "/proc/bus/input/devices"]
        out, err = self.execute_cmd(cmd)

        if err:
            #print("Error trying to read input devices:%s" % (err,))
            pass
        else:
            for line in out.split("\n"):
                if line != '':
                    if line.startswith(self.name_line):
                        dev_name = line[len(self.name_line):]
                        dev_name = dev_name[:-1]
                    elif line.startswith(self.keyboard_line):
                        kbd_obj = {'name': dev_name, 'extra': ''}
                        self.keyboards.append( kbd_obj )
                    elif line.startswith(self.mouse_line):
                        extra = ''
                        if dev_name.startswith("FT5406 memory based driver"):
                            extra = "Touch Screen"
                        mouse_obj = {'name': dev_name, 'extra': extra}
                        self.mice.append( mouse_obj )

        # query output devices. 

        screen_name = ''
        cmd = ["cat", "/sys/class/graphics/fb0/name"]
        out, err = self.execute_cmd(cmd)

        if err:
            #print("Error trying to read output devices:%s" % (err,))
            pass
        else:
            screen_name = out.strip()

        screen_resolution = ''
        cmd = ["cat", "/sys/class/graphics/fb0/virtual_size"]
        out, err = self.execute_cmd(cmd)

        if err:
            #print("Error trying to read output devices:%s" % (err,))
            pass
        else:
            screen_resolution = out.strip()

        screen_depth = ''
        cmd = ["cat", "/sys/class/graphics/fb0/bits_per_pixel"]
        out, err = self.execute_cmd(cmd)

        if err:
            #print("Error trying to read output devices:%s" % (err,))
            pass
        else:
            screen_depth = out.strip()

        if not (screen_name == '' and screen_resolution == ''):
            self.screens = [ {'name': screen_name, 'resolution': screen_resolution, 'pel_size': screen_depth, 'extra': ''} ]


        capabilities = {'keyboards':self.keyboards, 'mice':self.mice, 'screens':self.screens}
        return capabilities


if __name__ == "__main__":
    hardware_capabilities = EnclosureCapabilities()
    print("Kbds:%s" % (hardware_capabilities.keyboards,))
    print("Mice:%s" % (hardware_capabilities.mice,))
    print("Screens:%s" % (hardware_capabilities.screens,))