import json
import os.path
import subprocess

import code128
from lxml import etree

from bureau import Bureau, add_command, add_api


def clean_svg(svg):
    """
    This is a little hack that removes the height and width attributes from
    SVG strings as they confuse Firefox.  Sigh... hopefully this can go away
    some day.
    """
    utf8_parser = etree.XMLParser(encoding='utf-8')
    svg = svg.encode("utf-8")
    otree = etree.fromstring(svg, utf8_parser)
    del otree.attrib["height"]
    del otree.attrib["width"]
    clean_svg = etree.tostring(otree)
    return clean_svg.decode("utf-8")


class InhumanResources(Bureau):
    """
    This is a core functional bureau of the Screenless office it keeps track
    of all published methods provided by all other bureaus and can print
    the menu for the whole system or an individual item
    """

    name = "Inhuman Resources"
    prefix = "IR"
    version = 0

    def __init__(self):
        Bureau.__init__(self)
        self.menu = {}
        # update_commands(self)

    @add_api("addbureau", "Register Bureau")
    def add_bureau(self, data):
        """
        Register Bureau with Inhuman Resources

        data = { prefix: "IR",
                 name: "Inhuman Resources",
                 desc: "Keep track of public resources provided by bureaus"
               }
        """
        try:
            name = data["name"]
            prefix = data["prefix"]
            desc = data["desc"]
        except KeyError as e:
            print("cannot add invalid bureau:", str(e))
            return str(e)
        print("added menu")
        self.menu[prefix] = {"name": name,
                             "desc": desc,
                             "commands": {},
                             "apis": {}}

    @add_api("addcommand", "Register Command")
    def add_cmd(self, data):
        try:
            prefix = data["prefix"]
            cmd = data["cmd"]
            cmdname = data["cmdname"]
            desc = data["desc"]
            cmd_code = prefix + cmd + "."
            barcode = clean_svg(code128.svg(prefix + cmd + "."))
            barcode_png = os.path.join(self.datadir, cmd_code + "png")
            code128.image(cmd_code).save(barcode_png)
            barcode_png = str(barcode_png)
        except KeyError as e:
            print("cannot add invalid command:", str(e))
            return
        if prefix not in self.menu:
            # TODO: this should throw some kind of error message/log
            print("error: cannot add command ", cmd, "to non-existent prefix",
                  prefix)
        else:
            self.menu[prefix]["commands"][cmd] = {"name": cmdname,
                                                  "desc": desc,
                                                  "barcode": barcode,
                                                  "barcode_png": barcode_png}

    @add_api("addapi", "Register API Method")
    def add_api_method(self, data):
        try:
            prefix = data["prefix"]
            cmd = data["api"]
            cmdname = data["apiname"]
            desc = data["desc"]
        except KeyError as e:
            print("cannot add invalid command:", str(e))
            return
        if prefix not in self.menu:
            # TODO: this should throw some kind of error message/log
            print("error: cannot add command ", cmd, "to non-existent prefix",
                  prefix)
        else:
            self.menu[prefix]["apis"][cmd] = {"name": cmdname,
                                              "desc": desc}

    @add_command("menu", "Print Menu")
    def print_menu(self):
        """
        Prints the menu of commands for all operational bureaus.
        """
        self.print_full("menu.html", menu=self.menu)

    @add_command("update", "Restructure Organization")
    def update(self):
        """
        Restructure the organization.  This may include firing, hiring,
        refinancing and organizational changes.  This will update the 
        Office to the latest software but it may be disruptive to your
        current personal and social situation.  After pulling the latest
        updates, all bureaus other than management will be restarted.
        """
        subprocess.call("git pull")
        self.restart()

    @add_command("restart", "Furlough")
    def restart(self):
        """
        Send the entire organization on a very short unpaid vacation.  This
        will restart all bureaus, so it may cause disruption, loss of work
        and other psycho-social side effects of a loss of state.  It may 
        also help restore a messed up office to normal operation.
        """
        # TODO: find the PID of mgmt and send it a HUP signal
        pass


def main():
    hr = InhumanResources()
    hr.run()

if __name__ == "__main__":
    hr = InhumanResources()
    hr.run()