#!/usr/bin/env python3

import sys
import serial
import time
import logging
import readline
import yaml
import types

from ugv import UGVComms
import messages_pb2 as messages
import config_pb2

log = logging.getLogger("ugv_cmd")


def dict2pb(d, pb):
    for key in d:
        val = d[key]
        if isinstance(val, dict):
            dict2pb(val, getattr(pb, key))
        else:
            setattr(pb, key, val)


class CLI_CMD:
    def __init__(self, func, names=[], description=""):
        self.func = func
        self.names = names
        self.description = description


cli_commands = []


def cli_cmd(names=None, description=""):
    def dec(fn: types.FunctionType):
        if dec.names is None:
            dec.names = [fn.__name__]
        cli_commands.append(CLI_CMD(fn, dec.names, dec.description))
        return fn

    dec.names = names
    dec.description = description

    return dec


class UGV_CLI:
    def __init__(self):
        self.is_running = False
        self.last_state = messages.STATE_IDLE
        self.commands = {
            'get_status': self.get_status,
            's': self.get_status,
        }
        self.ugv = None
        pass

    @cli_cmd(names=["help", "h", "?"], description="Print this help message")
    def help_msg(self):
        print("Commands:")
        for cmd in cli_commands:
            names = ", ".join(cmd.names).ljust(30, ' ')
            print("{}: {}".format(names, cmd.description))
        print()

    @cli_cmd(names=["exit", "q", "C-d", "C-c"], description="Quit the program")
    def exit(self):
        self.is_running = False

    @cli_cmd(names=["disable", "d"], description="Disable the UGV")
    def disable(self):
        self.ugv.write_command(messages.CMD_DISABLE)

    @cli_cmd(names=["set_target", "st"], description="Set the target to <lat> <long>")
    def set_target(self, lat=34.068415, long=-118.443217):
        lat = float(lat)
        long = float(long)
        cmd = messages.GroundCommand()
        cmd.type = messages.CMD_SET_TARGET
        cmd.target_location.latitude = lat
        cmd.target_location.longitude = long
        self.ugv.write_command(cmd)
        log.info("set target to (%f, %f)", lat, long)

    @cli_cmd(names=["set_config", "sc"], description="Load configuration from config.yml and send")
    def set_config(self):
        with open('./tools/config.yml', 'r') as configfile:
            config = yaml.load(configfile)

        if 'REVISION' in config:
            config_rev = config['REVISION']
            del config['REVISION']
        else:
            config_rev = 1

        cmd = messages.GroundCommand()
        cmd.type = messages.CMD_SET_CONFIG
        dict2pb(config, cmd.config)
        self.ugv.write_command(cmd)
        log.info("updated config")

    @cli_cmd(names=["drive_heading", "dh"], description="Drive a <heading> with a forward <power>")
    def drive_heading(self, heading=65, power=0.0):
        heading = float(heading)
        power = float(power)
        cmd = messages.GroundCommand()
        cmd.type = messages.CMD_DRIVE_HEADING
        cmd.drive_heading.heading = heading
        cmd.drive_heading.power = power
        self.ugv.write_command(cmd)
        log.info("driving heading %f at power %f", heading, power)

    @cli_cmd(names=["drive_to_target", "dt"], description="Drive to the drop target")
    def drive_to_target(self):
        cmd = messages.GroundCommand()
        cmd.type = messages.CMD_DRIVE_TO_TARGET
        self.ugv.write_command(cmd)
        log.info("driving to target")

    @cli_cmd(names=["last_status", "ls", "s"], description="Print the last status of the UGV")
    def last_status(self):
        if self.ugv.last_status_time is None:
            log.info("no status received")
        else:
            last_status_delay = time.time() - self.ugv.last_status_time
            log.info("last status (%.4f seconds ago): %s",
                     last_status_delay, self.ugv.last_status)

    @cli_cmd(names=["get_status", "gs"], description="Get the current status of the UGV")
    def get_status(self):
        cmd = messages.GroundCommand()
        cmd.type = messages.CMD_GET_STATUS
        self.ugv.write_command(cmd)
        self.last_status()

    @cli_cmd(names=["ping", "p"], description="Ping the UGV")
    def get_status(self):
        cmd = messages.GroundCommand()
        cmd.type = messages.CMD_PING
        self.ugv.write_command(cmd)
        print("Received ping response")

    @staticmethod
    def find_command(name):
        for cmd in cli_commands:
            if name in cmd.names:
                return cmd
        return None

    @staticmethod
    def complete_command(text, state):
        options = [name for cmd in cli_commands for name in cmd.names if name.startswith(text)]
        if state < len(options):
            return options[state]
        else:
            return None

    def start(self):
        self.is_running = True

        if len(sys.argv) >= 2:
            ser_url = sys.argv[1]
        else:
            ser_url = "hwgrep://USB"
        ser = serial.serial_for_url(ser_url, baudrate=9600, parity=serial.PARITY_NONE,
                                    stopbits=serial.STOPBITS_ONE, bytesize=serial.EIGHTBITS,
                                    timeout=0.5)

        readline.parse_and_bind("tab: complete")
        readline.set_completer(self.complete_command)

        self.ugv = UGVComms(ser)
        self.ugv.start()
        time.sleep(0.2)
        last_line = None
        try:
            print("Run 'help' to find out what commands are available")
            while self.is_running:
                line = input("UGV> ")
                if len(line) is 0 and last_line is not None:
                    print(last_line)
                    line = last_line
                line_parts = line.split(' ')
                if len(line_parts) is 0:
                    continue
                cmd = self.find_command(line_parts[0])
                if cmd is None:
                    print("Unknown command: '%s'" % line_parts[0])
                    continue
                last_line = line
                try:
                    cmd.func(self, *line_parts[1:])
                except KeyboardInterrupt:
                    print("Command interrupted")
                except Exception as e:
                    print("Error executing command: ", e)
            # TODO: continuously write state
            # while True:
            #    if self.ugv.last_status is None or self.ugv.last_status.state is not messages.STATE_DRIVE_HEADING:
        except (KeyboardInterrupt, EOFError):
            self.exit()
        finally:
            log.info("disabling UGV...")
            try:
                self.ugv.write_command(messages.CMD_DISABLE)
                log.info("done. exiting")
            except KeyboardInterrupt:
                log.info("force exiting...")
            self.ugv.stop()


if __name__ == "__main__":
    logging.basicConfig(
        format='%(asctime)s [%(name)s] %(levelname)s: %(message)s', datefmt='%Y-%b-%d %H:%M:%S')
    logging.getLogger().setLevel(logging.INFO)
    UGV_CLI().start()