#
# Copyright 2015 (c) Anna Schumaker.
#

from . import chat

#
# This class represents a slack "thread", which could be a channel, group,
# or chat.  Note that child classes need to implement the following methods:
#
# - do_fetch_info():     Call <whatever>.info to find unread count and timestamp.
# - do_fetch_messages(): Call <whatever>.history to find unread messages.
# - do_mark_messages():  Call <whatever>.mark to set unread cursor.
#
class Thread:
    def __init__(self, json):
        self.__id      = json.get("id", 0)
        self.__name    = json.get("name", "").title()
        self.__topic   = json["topic"].get("value", "").encode("utf-8").decode("latin-1")
        self.__purpose = json["purpose"].get("value", "").encode("utf-8").decode("latin-1")
        self.__unread  = json.get("unread_count", None)
        self.__last_ts = json.get("last_read", None)

    def __str__(self):
        topic=""
        if self.__topic != "":
            topic = "\nTopic: %s" % self.__topic
        return "%s: %s%s" % (self.__name, self.__purpose, topic)

    def fetch_info(self):
        json = self.do_fetch_info()
        if json != None:
            self.__unread  = json.get("unread_count", None)
            self.__last_ts = json.get("last_read", None)

    def id(self):
        return self.__id

    def is_member(self):
        return True

    def name(self):
        return self.__name

    def read(self):
        if self.__last_ts == None:
            self.fetch_info()

        # Read original message list
        o_list = []
        for message in self.do_fetch_messages(self.__last_ts):
            o_list += [ chat.Message(message) ]
        o_list.sort()

        # Merge together messages from the same user
        m_list = [ o_list[0] ]
        for msg in o_list[1:]:
            if msg.user() == m_list[-1].user():
                m_list[-1].merge(msg)
            else:
                m_list += [ msg ]

        self.do_mark_messages(m_list[-1].ts())
        return m_list

    def unread_count(self):
        if self.__unread == None:
            self.fetch_info()
        return self.__unread

    def post(self, text):
        chat.post_message(self.__id, text)