from kmk.modules import Module
from usb_cdc import data
import json

import json_layer

class Client(Module):
    """ Listen the connections from host, and apply the actions depending of
        the json command.
    """

    def during_bootup(self, keyboard):
        try:
            # Do not set any timeout, we check before reading a string if there
            # is any content to read, but block to be sure to read everything.
            data.timeout = None
        except AttributeError:
            pass

    def process_key(self, keyboard, key, is_pressed, int_coord):
        return key

    def before_hid_send(self, keyboard):

        # Serial.data isn't initialized yet.
        if not data:
            return

        if not data.connected:
            keyboard.keymap[0].name = "Disconnected"
            return

        # Nothing to parse.
        if data.in_waiting <= 0:
            return
        line = data.readline()
        if not line:
            return

        try:
            content = line.decode().strip()
            if not content:
                # If strip produced an empty string, stop here.
                return
            jdata = json.loads(content)
        except ValueError as err:
            # In circuitPython, json error are reported as ValueError.
            # seet https://docs.circuitpython.org/en/latest/docs/library/json.html#json.load
            print(err, line)
            return

        # Json is valid, try to read the command, and consider the input is a
        # direct raw layer instruction if this does not work.

        actions = {
            "layer" : lambda x : keyboard.keymap[0].load(x),
        }

        try:
            for action, args in jdata.items():
                actions[action](args)
            return
        except Exception as err:
            pass

        try:
            keyboard.keymap[0].load(jdata)
        except Exception as err:
            print("rawdata:", err)
            return

    def before_matrix_scan(self, keyboard):
        """ Default implementation, do nothing.
        """

    def after_matrix_scan(self, keyboard):
        """ Default implementation, do nothing.
        """

    def after_hid_send(self, keyboard):
        """ Default implementation, do nothing.
        """

    def on_powersave_enable(self, keyboard):
        """ Default implementation, do nothing.
        """

    def on_powersave_disable(self, keyboard):
        """ Default implementation, do nothing.
        """