# Copyright 2016 Mycroft AI, Inc.
#
# This file is part of Mycroft Core.
#
# Mycroft Core is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Mycroft Core is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Mycroft Core.  If not, see <http://www.gnu.org/licenses/>.


import json
import sys
import time
from threading import Timer

import os
from os.path import expanduser, exists

from mycroft.configuration import ConfigurationManager
from mycroft.messagebus.client.ws import WebsocketClient
from mycroft.skills.core import load_skills, THIRD_PARTY_SKILLS_DIR, \
    load_skill, create_skill_descriptor, MainModule
from mycroft.util.log import getLogger

logger = getLogger("Skills")

__author__ = 'seanfitz'

ws = None
loaded_skills = {}
last_modified_skill = 0
skills_directories = []


def connect():
    global ws
    ws.run_forever()


def load_watch_skills():
    global ws, loaded_skills, last_modified_skill, skills_directories

    skills_directories = [os.path.dirname(os.path.abspath(__file__))]
    skills_directories = skills_directories + THIRD_PARTY_SKILLS_DIR

    try:
        config = ConfigurationManager.get().get("skills")
        ini_third_party_skills_dir = expanduser(config.get("directory"))
        if ini_third_party_skills_dir and exists(ini_third_party_skills_dir):
            skills_directories.append(ini_third_party_skills_dir)
    except AttributeError as e:
        logger.warning(e.message)

    timer = Timer(0, watch_skills)
    timer.daemon = True
    timer.start()


def clear_skill_events(instance):
    global ws
    events = ws.emitter._events
    instance_events = []
    for event in events:
        e = ws.emitter._events[event]
        if len(e) > 0 and e[0].func_closure and isinstance(
                e[0].func_closure[1].cell_contents, instance.__class__):
            instance_events.append(event)

    for event in instance_events:
        del events[event]


def watch_skills():
    global ws, loaded_skills, last_modified_skill, skills_directories
    for dir in skills_directories:
        if exists(dir):
            list = filter(lambda x: os.path.isdir(os.path.join(dir, x)),
                          os.listdir(dir))
            for skill_folder in list:
                if not skill_folder in loaded_skills:
                    loaded_skills[skill_folder] = {}
                skill = loaded_skills.get(skill_folder)
                skill["path"] = os.path.join(dir, skill_folder)
                if not MainModule + ".py" in os.listdir(skill["path"]):
                    continue
                skill["last_modified"] = max(
                    os.path.getmtime(root) for root, _, _ in
                    os.walk(skill["path"]))
                if skill.get("instance") and skill.get("last_modified",
                                                    0) <= last_modified_skill:
                    continue
                elif skill.get("instance") and skill.get("last_modified",
                                                    0) > last_modified_skill:
                    logger.debug("Reloading Skill: " + skill_folder)
                    skill["instance"].shutdown()
                    clear_skill_events(skill["instance"])
                    del skill["instance"]
                skill["instance"] = load_skill(
                    create_skill_descriptor(skill["path"]), ws)
    last_modified_skill = max(
        map(lambda x: x.get("last_modified"), loaded_skills.values()))
    time.sleep(2)
    watch_skills()


def main():
    global ws
    ws = WebsocketClient()
    ConfigurationManager.init(ws)

    def echo(message):
        try:
            _message = json.loads(message)

            if _message.get("type") == "registration":
                # do not log tokens from registration messages
                _message["data"]["token"] = None
            message = json.dumps(_message)
        except:
            pass
        logger.debug(message)

    ws.on('message', echo)
    ws.once('open', load_watch_skills)
    ws.run_forever()


if __name__ == "__main__":
    try:
        main()
    except KeyboardInterrupt:
        for skill in loaded_skills:
            skill.shutdown()
    finally:
        sys.exit()