# bureau
import functools
import json
import os.path
import subprocess
import tempfile
import threading
import time

import zmq
from mako.template import Template


def update_commands(cls):
    for name, method in cls.__dict__.items():
        print("name %s method %s" % (name, method))
        if hasattr(method, "command"):
            comstr = method.command
            cls.commands[comstr] = method
    return cls


def add_command(comstr, name=""):
    def decorator(func):
        @functools.wraps(func)
        def func_wrap(*args, **kwargs):
            return func(*args, **kwargs)
        func_wrap.command = comstr
        func_wrap.name = name
        return func_wrap
    return decorator


def add_api(apistr, name=""):
    def decorator(func):
        @functools.wraps(func)
        def func_wrap(*args, **kwargs):
            return func(*args, **kwargs)
        func_wrap.api = apistr
        func_wrap.name = name
        return func_wrap
    return decorator


class Bureau:
    name = "TEST"
    prefix = "00"
    version = 0

    config = {}

    def __init__(self):
        """ set up ZeroMQ connections and register commands"""
        self.commands = {}
        self.api = {}

        if not os.path.exists(".screenless"):
            os.mkdir(".screenless")

        self.context = zmq.Context()
        self._recv = self.context.socket(zmq.REP)
        self._recv.bind("ipc://.screenless/" + self.prefix + ".ipc")
        print(("bureau " + self.name + " waiting for messages"))
        print("commands: ")
        print(self.commands)

    def send(self, recipient, message, data=None):
        message += "."
        if data:
            message += json.dumps(data)
        sender = self.context.socket(zmq.REQ)
        sender.connect("ipc://.screenless/" + recipient + ".ipc")
        sender.send_string(message)
        # TODO: retry this a few times with a proper sleep/timeout
        time.sleep(0.5)
        try:
            ret = json.loads(sender.recv(flags=zmq.NOBLOCK))
        except zmq.ZMQError:
            print("message sent but got no reply...")
            ret = None
        return ret

    def _publish_methods(self):
        # register bureau with Inhuman Resources
        bureau_detail = {"name": self.name, "prefix": self.prefix,
                         "desc": self.__doc__}
        self.send("IR", "addbureau", bureau_detail)

        # find and store all published methods
        for member in dir(self):
            method = getattr(self, member)
            # ignore anything that is not a method with command or api details
            if not (callable(method) and (hasattr(method, "command") or
                                          hasattr(method, "api"))):
                continue
            if hasattr(method, "command"):
                self.commands[method.command] = method
                cmd_detail = {"cmdname": method.name,
                              "prefix": self.prefix,
                              "cmd": method.command,
                              "desc": method.__doc__}
                self.send("IR", "addcommand", cmd_detail)
            elif hasattr(method, "api"):
                self.api[method.api] = method
                api_detail = {"apiname": method.name,
                              "prefix": self.prefix,
                              "api": method.api,
                              "desc": method.__doc__}
                self.send("IR", "addapi", api_detail)

        print("registered:")
        print(self.commands)
        print(self.api)

    def print_full(self, template, **kwargs):
        """print a full page (A4) document """
        # TODO: look up the printer LPR name

        lpname = kwargs.get("printer", "default")
        templ = Template(filename=template)

        texfile, texfilepath = tempfile.mkstemp(".tex")
        texfile.write(templ.render_unicode(
            **kwargs).encode('utf-8', 'replace'))

        texdir = os.path.dirname(texfilepath)

        subprocess.call("cd " + texdir + "; xelatex " + texfilepath)

        pdffile = texfilepath[0:-4] + ".pdf"

        subprocess.call("lpr -P " + lpname + " " + pdffile)

    def print_small(self, text, printer="/dev/usb/lp1"):
        lp = open(printer, "w")
        text += "\r\n" * 10
        text += ".d0"
        lp.write(text)
        lp.close()

    @add_command("test")
    def test(self, data):
        # stupid test to see if modules work
        print(("hi! testing. " + self.name + " bureau seems to work!"))
        return b"seems to work."

    def run_io(self):
        """process hardware or timed input

        This method can be ignored for most Bureaus.
        It should be overloaded for any services that need to independently
        generate messages as this is just a placeholder.
        It is run in a separate thread and should handle any input or
        timed events.  Messages are then sent to other Bureaus via the
        self.send connection to the OfficeManager.  Don't forget to
        to consier thread safety issues when accessing data!
        """
        pass

    def run(self):
        """main loop for processing messages

        This runs all relelvant event processing loops.
        """

        # start the hardware input handler
        io = threading.Thread(target=self.run_io)
        io.start()

        # register commands and api methods
        self._publish_methods()

        while True:
            try:
                msg = self._recv.recv_string(flags=zmq.NOBLOCK)
            except zmq.ZMQError:
                time.sleep(0.05)  # don't waste CPU
                continue
            try:
                dot = msg.find(".")
                ref = msg[:dot]
                if (dot < len(msg) - 1) and (dot > 0):
                    data = msg[dot + 1:]
                else:
                    data = None
                print("data: " + str(data))
            except IndexError as e:
                print("invalid message: ", e)
                continue
            print(("got method: " + ref))

            if (ref in self.commands) or (ref in self.api):
                # catch TypeErrors for case of bogus params
                try:
                    if ref in self.api:
                        data = json.loads(data)
                        ret = self.api[ref](data)
                    else:
                        ret = self.commands[ref](data)
                    if ret is None:
                        ret = ""
                    ret = b"0" + ret
                    self._recv.send(ret)
                except TypeError as e:
                    print(e)
                    print("invalid data for command '{}': {}".format(ref, data))
                    self._recv.send_unicode("Error.  Invalid or missing data.")
                except KeyError as e:
                    print(e)
                    print("You are calling a command as an API or vice-versa.")
                    self._recv.send_unicode(
                        "Error. Command called as API or API as command.")
            else:
                print("error! Command/API %s not found", ref)
                self._recv.send_unicode("Error! Command/API not found.")


if __name__ == "__main__":
    test = Bureau()
    test.run()