import asyncio
import os
import random

# For key generation
import string

# Squash errors
import warnings
from concurrent.futures import ProcessPoolExecutor

# For timestamp processing
from datetime import datetime
from math import ceil

import orjson
import regex

# Tokenisation
import spacy

# For 4chan message parsing
from bs4 import BeautifulSoup
from numpy import array_split
from polyglot.detect.base import logger as polyglot_logger

# For NLP
from polyglot.text import Text
from pycld2 import error as cld2_error
from siphashc import siphash

# For sentiment
from vaderSentiment.vaderSentiment import SentimentIntensityAnalyzer

import db
import util

# 4chan schema
from schemas.ch4_s import ATTRMAP

# For tokenisation
# from gensim.parsing.preprocessing import (
#     strip_tags,
#     strip_punctuation,
#     strip_numeric,
#     stem_text,
#     strip_multiple_whitespaces,
#     strip_non_alphanum,
#     remove_stopwords,
#     strip_short,
#     preprocess_string,
# )

# CUSTOM_FILTERS = [
#     lambda x: x.lower(),
#     strip_tags,  #
#     strip_punctuation,  #
#     strip_multiple_whitespaces,
#     strip_numeric,
#     remove_stopwords,
#     strip_short,
#     #stem_text,
#     strip_non_alphanum,  #
# ]

RE_BAD_CHARS = regex.compile(r"[\p{Cc}\p{Cs}]+")

# Squash errors
polyglot_logger.setLevel("ERROR")
warnings.filterwarnings("ignore", category=UserWarning, module="bs4")


TAGS = ["NOUN", "ADJ", "VERB", "ADV"]
nlp = spacy.load("en_core_web_sm", disable=["parser", "ner"])


log = util.get_logger("process")

# Maximum number of CPU threads to use for post processing
CPU_THREADS = int(os.getenv("MONOLITH_PROCESS_THREADS", os.cpu_count()))

p = ProcessPoolExecutor(CPU_THREADS)


def get_hash_key():
    hash_key = db.r.get("hashing_key")
    if not hash_key:
        letters = string.ascii_lowercase
        hash_key = "".join(random.choice(letters) for i in range(16))
        log.debug(f"Created new hash key: {hash_key}")
        db.r.set("hashing_key", hash_key)
    else:
        hash_key = hash_key.decode("ascii")
        log.debug(f"Decoded hash key: {hash_key}")
    return hash_key


hash_key = get_hash_key()


@asyncio.coroutine
async def spawn_processing_threads(data):
    len_data = len(data)
    # log.debug(f"Spawning processing threads for batch of {len_data} messages")

    loop = asyncio.get_event_loop()
    tasks = []

    if len(data) < CPU_THREADS:
        split_data = [data]
    else:
        msg_per_core = int(len(data) / CPU_THREADS)
        split_data = array_split(data, ceil(len(data) / msg_per_core))
    for index, split in enumerate(split_data):
        # log.debug(f"Delegating processing of {len(split)} messages to thread {index}")
        task = loop.run_in_executor(p, process_data, split)
        tasks.append(task)

    results = [await task for task in tasks]
    log.debug(
        (
            f"Results from processing of {len_data} messages in "
            f"{len(split_data)} threads: {len(results)}"
        )
    )

    # Join the results back from the split list
    flat_list = [item for sublist in results for item in sublist]
    await db.store_kafka_batch(flat_list)

    # log.debug(f"Finished processing {len_data} messages")


def process_data(data):
    to_store = []

    # Initialise sentiment analyser
    analyzer = SentimentIntensityAnalyzer()
    for msg in data:

        # normalise fields
        for key, value in list(msg.items()):
            if value is None:
                del msg[key]

        # Remove invalid UTF-8 characters
        # IRC and Discord
        if "msg" in msg:
            msg["msg"] = RE_BAD_CHARS.sub("", msg["msg"])

        # 4chan - since we change the attributes below
        if "com" in msg:
            msg["com"] = RE_BAD_CHARS.sub("", msg["com"])

        if msg["src"] == "4ch":
            board = msg["net"]
            thread = msg["channel"]

            # Calculate hash for post
            post_normalised = orjson.dumps(msg, option=orjson.OPT_SORT_KEYS)
            hash = siphash(hash_key, post_normalised)
            hash = str(hash)
            redis_key = f"cache.{board}.{thread}.{msg['no']}"
            key_content = db.r.get(redis_key)
            if key_content:
                key_content = key_content.decode("ascii")
                if key_content == hash:
                    # This deletes the message since the append at the end won't be hit
                    continue
                else:
                    msg["type"] = "update"
            db.r.set(redis_key, hash)
            for key2, value in list(msg.items()):
                if key2 in ATTRMAP:
                    msg[ATTRMAP[key2]] = msg[key2]
                    del msg[key2]

            if "ts" in msg:
                old_time = msg["ts"]
                # '08/30/22(Tue)02:25:37'
                time_spl = old_time.split(":")
                if len(time_spl) == 3:
                    old_ts = datetime.strptime(old_time, "%m/%d/%y(%a)%H:%M:%S")
                else:
                    old_ts = datetime.strptime(old_time, "%m/%d/%y(%a)%H:%M")
                # new_ts = old_ts.isoformat()
                new_ts = int(old_ts.timestamp())
                msg["ts"] = new_ts
            else:
                raise Exception("No TS in msg")
            if "msg" in msg:
                soup = BeautifulSoup(msg["msg"], "html.parser")
                msg_str = soup.get_text(separator="\n")
                msg["msg"] = msg_str

        # Annotate sentiment/NLP
        if "msg" in msg:
            RE_BAD_CHARS.sub("", msg["msg"])
            # Language
            text = Text(msg["msg"])
            try:
                lang_code = text.language.code
                lang_name = text.language.name
                msg["lang_code"] = lang_code
                msg["lang_name"] = lang_name
            except cld2_error as e:
                log.error(f"Error detecting language: {e}")
                # So below block doesn't fail
                lang_code = None

            # Blatant discrimination
            if lang_code == "en":

                # Sentiment
                vs = analyzer.polarity_scores(str(msg["msg"]))
                addendum = vs["compound"]
                msg["sentiment"] = addendum

                # Tokens
                n = nlp(msg["msg"])
                for tag in TAGS:
                    tag_name = tag.lower()
                    tags_flag = [token.lemma_ for token in n if token.pos_ == tag]
                    msg[f"words_{tag_name}"] = tags_flag

        # Add the mutated message to the return buffer
        to_store.append(msg)
    return to_store