import os
import os.path
import re
import sys
from glob import glob
from time import sleep
from urllib.request import urlretrieve
import urllib.error

packages_to_install = "pyquery==2.0.0 tqdm==4.66.1"
cmd_for_install = sys.executable + " -m pip install "
for i in range(3):
    try:
        from pyquery import PyQuery as pq  # type: ignore
        from tqdm import trange, tqdm
        from tqdm.contrib.concurrent import thread_map

        break
    except ImportError:
        if os.system(cmd_for_install + packages_to_install) != 0:
            os.system(cmd_for_install + " --user " + packages_to_install)


links_to_files: list = []


class ArchiveNotFound(Exception):
    pass


class patterns:
    RN = re.compile(r"[\r\n]{2,}")
    TIME = re.compile(r" в [\d]{1,2}:[\d]{1,2}:[\d]{1,2}")
    DELMSG = re.compile("Сообщение удалено[\n]?")
    EDITEDMSG = re.compile(r"\(ред\.\)")
    SLUG = re.compile(r"[^\w\s-]")
    ONLY_DIGITS = r"[\D]+"


def get_user_aaction(prompt: str) -> str:
    action = ""
    while len(action) > 0:
        action = re.sub(patterns.ONLY_DIGITS, "", input(prompt)).strip()
    return action


def isInt(value):
    try:
        int(value)
    except ValueError:
        return False
    return True


def norm(value: str) -> str:
    for pattern in [patterns.RN, patterns.TIME, patterns.EDITEDMSG, patterns.DELMSG]:
        value = re.sub(pattern, "\n" if pattern == patterns.RN else "", value)
    return value.strip() + "\n\n"


def slugify(value: str) -> str:
    value = re.sub(patterns.SLUG, "", value.lower())
    return re.sub(r"[-\s]+", "-", value).strip("-_")


def get_dir_with_messages() -> str:
    cwd = os.getcwd()
    cwd2 = ""
    for a in sys.argv:
        if os.path.isdir(a):
            cwd = a
    cwd2 = os.path.join(cwd, "messages")
    if os.path.isdir(cwd2):
        cwd = cwd2
    if not os.path.isfile(os.path.join(cwd, "index-messages.html")):
        raise ArchiveNotFound("")
    return cwd


def export_to_txt(files_with_messages: list, results_folder: str):
    with open(files_with_messages[-1], "r", encoding="CP1251") as fp:
        d = pq(fp.read())
    chat_title = d("div.ui_crumb:last").text().strip()
    txtfile = slugify(chat_title)
    txtfile = os.path.join(results_folder, txtfile + ".txt")
    with open(txtfile, "w", encoding="UTF-8") as txtfp:
        txtfp.write("\ufeff")
        for i in trange(len(files_with_messages), leave=None, delay=1.5, unit="pg"):
            f = files_with_messages[i]
            with open(f, "r", encoding="CP1251") as fp:
                d = pq(fp.read())
            messages: list = list(d("div.item").items())
            messages.reverse()
            txtfp.writelines([norm(m.text()) for m in messages])
            attachments_links = d("a.attachment__link").items()
            for attachment_link in attachments_links:
                links_to_files.append(attachment_link.attr("href"))


def process_chat(path_to_chat: str, results_folder: str = "."):
    d = None
    files_with_messages: list = glob(
        os.path.join(path_to_chat, "messages*.html"), recursive=False
    )
    if not files_with_messages:
        return
    files_with_messages.sort(
        key=lambda x: int(os.path.basename(x).split("s")[-1][:-5]),
        reverse=True,
    )
    export_to_txt(files_with_messages, results_folder)


def main():
    try:
        p = get_dir_with_messages()
    except ArchiveNotFound:
        print(
            """
            Неверно указан путь к папке с архивом.
            Измените рабочую директорию
            или передайте нужный путь в аргументе командной строки при вызове этой утилиты.
        """.strip()
        )
        sys.exit(1)
    chats = list(
        filter(
            lambda x: isInt(os.path.basename(x)),
            [
                c
                for c in glob(p + os.path.sep + "*", recursive=False)
                if os.path.isdir(p)
            ],
        )
    )
    print("I'm starting to work. %d chats found." % (len(chats),))
    results_folder = os.path.join(p, "mre")
    if not os.path.isdir(results_folder):
        os.mkdir(results_folder)
    results = thread_map(
        lambda x: process_chat(x, results_folder),
        chats,
        leave=None,
        miniters=1,
        unit="chat",
    )
    del results
    with open("links_to_files.txt", "w", encoding="UTF-8") as fp:
        fp.write( "\n".join(links_to_files) )
    print("Скачиваю вложения...")
    attachments_dir = os.path.join(results_folder, "attachments")
    if not os.path.isdir(attachments_dir):
        os.mkdir(attachments_dir)
    for url in tqdm(links_to_files):
        filename = os.path.join(attachments_dir, url.split("/")[-1].split("?")[0])
        try:
            urlretrieve(url, filename)
        except urllib.error.HTTPError:
            print(f"Ошибка при скачивании {filename}")
    sleep(1)
    print(" ")
    print("Завершено! Текстовые файлы находятся по пути:\r\n", results_folder)


if __name__ == "__main__":
    main()