from collections import OrderedDict

import glob
import io
import json
import os

from slackviewer.formatter import SlackFormatter
from slackviewer.message import Message
from slackviewer.user import User, deleted_user


class Reader(object):
    """
    Reader object will read all of the archives' data from the json files
    """

    def __init__(self, PATH):
        self._PATH = PATH
        # TODO: Make sure this works
        with io.open(os.path.join(self._PATH, "users.json"), encoding="utf8") as f:
            self.__USER_DATA = {u["id"]: User(u) for u in json.load(f)}
            slackbot = {
                "id": "USLACKBOT",
                "name": "slackbot",
                "profile": {
                    "image_24": "https://a.slack-edge.com/0180/img/slackbot_24.png",
                    "image_32": "https://a.slack-edge.com/2fac/plugins/slackbot/assets/service_32.png",
                    "image_48": "https://a.slack-edge.com/2fac/plugins/slackbot/assets/service_48.png",
                    "image_72": "https://a.slack-edge.com/0180/img/slackbot_72.png",
                    "image_192": "https://a.slack-edge.com/66f9/img/slackbot_192.png",
                    "image_512": "https://a.slack-edge.com/1801/img/slackbot_512.png",
                }
            }
            self.__USER_DATA.setdefault("USLACKBOT", User(slackbot))

    ##################
    # Public Methods #
    ##################

    def compile_channels(self, channels=None):
        if isinstance(channels, str):
            channels = channels.split(',')

        channel_data = self._read_from_json("channels.json")
        channel_names = [c["name"] for c in channel_data.values() if not channels or c["name"] in channels]

        return self._create_messages(channel_names, channel_data)

    def compile_groups(self):

        group_data = self._read_from_json("groups.json")
        group_names = [c["name"] for c in group_data.values()]

        return self._create_messages(group_names, group_data)

    def compile_dm_messages(self):
        # Gets list of dm objects with dm ID and array of members ids
        dm_data = self._read_from_json("dms.json")
        dm_ids = [c["id"] for c in dm_data.values()]

        # True is passed here to let the create messages function know that
        # it is dm data being passed to it
        return self._create_messages(dm_ids, dm_data, True)

    def compile_dm_users(self):
        """
        Gets the info for the members within the dm

        Returns a list of all dms with the members that have ever existed

        :rtype: [object]
        {
            id: <id>
            users: [<user_id>]
        }

        """

        dm_data = self._read_from_json("dms.json")
        dms = dm_data.values()
        all_dms_users = []

        for dm in dms:
            # checks if messages actually exist
            if dm["id"] not in self._EMPTY_DMS:
                # added try catch for users from shared workspaces not in current workspace
                try:
                    if "members" in dm:
                        users = dm["members"]
                    if "user" in dm:
                        users = [dm["user"]]
                    dm_members = {"id": dm["id"], "users": [self.__USER_DATA.setdefault(m, deleted_user(m)) for m in users]}
                    all_dms_users.append(dm_members)
                except KeyError:
                    dm_members = None

        return all_dms_users

    def compile_mpim_messages(self):

        mpim_data = self._read_from_json("mpims.json")
        mpim_names = [c["name"] for c in mpim_data.values()]

        return self._create_messages(mpim_names, mpim_data)

    def compile_mpim_users(self):
        """
        Gets the info for the members within the multiple person instant message

        Returns a list of all dms with the members that have ever existed

        :rtype: [object]
        {
            name: <name>
            users: [<user_id>]
        }

        """

        mpim_data = self._read_from_json("mpims.json")
        mpims = [c for c in mpim_data.values()]
        all_mpim_users = []

        for mpim in mpims:
            mpim_members = {"name": mpim["name"], "users": [] if "members" not in mpim.keys() else [self.__USER_DATA.setdefault(m, deleted_user(m)) for m in mpim["members"]]}
            all_mpim_users.append(mpim_members)

        return all_mpim_users

    @staticmethod
    def _extract_time(json):
        try:
            # Convert the timestamp part to float
            return float(json['ts'])
        except KeyError:
            return 0

    ###################
    # Private Methods #
    ###################

    def _create_messages(self, names, data, isDms=False):
        """
        Creates object of arrays of messages from each json file specified by the names or ids

        :param [str] names: names of each group of messages

        :param [object] data: array of objects detailing where to get the messages from in
        the directory structure

        :param bool isDms: boolean value used to tell if the data is dm data so the function can
        collect the empty dm directories and store them in memory only

        :return: object of arrays of messages

        :rtype: object
        """

        chats = {}
        empty_dms = []
        formatter = SlackFormatter(self.__USER_DATA, data)

        for name in names:

            # gets path to dm directory that holds the json archive
            dir_path = os.path.join(self._PATH, name)
            messages = []
            # array of all days archived
            day_files = glob.glob(os.path.join(dir_path, "*.json"))

            # this is where it's skipping the empty directories
            if not day_files:
                if isDms:
                    empty_dms.append(name)
                continue

            for day in sorted(day_files):
                with io.open(os.path.join(self._PATH, day), encoding="utf8") as f:
                    # loads all messages
                    day_messages = json.load(f)   

                    # sorts the messages in the json file
                    day_messages.sort(key=Reader._extract_time) 
                 
                    messages.extend([Message(formatter, d) for d in day_messages])

            chats[name] = messages
        chats = self._build_threads(chats)

        if isDms:
            self._EMPTY_DMS = empty_dms

        return chats

    def _build_threads(self, channel_data):
        """
        Re-orders the JSON to allow for thread building.

        :param [dict] channel_data: dictionary of all Slack channels and messages

        :return: None
        """
        for channel_name in channel_data.keys():
            replies = {}

            user_ts_lookup = {}
            items_to_remove = []
            for i, m in enumerate(channel_data[channel_name]):
                user = m._message.get('user')
                ts = m._message.get('ts')

                if user is None or ts is None:
                    continue

                k = (user, ts)
                if k not in user_ts_lookup:
                    user_ts_lookup[k] = []
                user_ts_lookup[k].append((i, m))

            for location, message in enumerate(channel_data[channel_name]):
                #   If there's a "reply_count" key, generate a list of user and timestamp dictionaries
                if 'reply_count' in message._message or 'replies' in message._message:
                    #   Identify and save where we are
                    reply_list = []
                    for reply in message._message.get('replies', []):
                        reply_list.append(reply)
                    reply_objects = []
                    for item in reply_list:
                        item_lookup_key = (item['user'], item['ts'])
                        item_replies = user_ts_lookup.get(item_lookup_key)
                        if item_replies is not None:
                            reply_objects.extend(item_replies)

                    if not reply_objects:
                        continue

                    sorted_reply_objects = sorted(reply_objects, key=lambda tup: tup[0])
                    for reply_obj_tuple in sorted_reply_objects:
                        items_to_remove.append(reply_obj_tuple[0])
                    replies[location] = [tup[1] for tup in sorted_reply_objects]
            # Create an OrderedDict of thread locations and replies in reverse numerical order
            sorted_threads = OrderedDict(sorted(replies.items(), reverse=True))

            for idx_to_remove in sorted(items_to_remove, reverse=True):
                # threads location hotfix
                channel_data[channel_name][idx_to_remove] = {'user': -1}

            # Iterate through the threads and insert them back into channel_data[channel_name] in response order
            for grouping in sorted_threads.items():
                location = grouping[0] + 1
                for reply in grouping[1]:
                    msgtext = reply._message.get("text")
                    if not msgtext or not msgtext.startswith("**Thread Reply:**"):
                        reply._message["text"] = "**Thread Reply:** {}".format(msgtext)
                    channel_data[channel_name].insert(location, reply)
                    location += 1
            # threads location hotfix
            data_with_sorted_threads = []
            for i, item in enumerate(channel_data[channel_name]):
                if isinstance(item, Message):
                    data_with_sorted_threads.append(item)
            channel_data[channel_name] = data_with_sorted_threads.copy()
        return channel_data

    def _read_from_json(self, file):
        """
        Reads the file specified from json and creates an object based on the id of each element

        :param str file: Path to file of json to read

        :return: object of data read from json file

        :rtype: object
        """

        try:
            with io.open(os.path.join(self._PATH, file), encoding="utf8") as f:
                return {u["id"]: u for u in json.load(f)}
        except IOError:
            return {}