import base64
import json
import os
import sys
import unicodedata

from . import logger
from apiclient import errors
from bs4 import BeautifulSoup, NavigableString, Tag
from pathlib import Path
from pytz import timezone
from gmail_helpers import GmailMessage
from email.utils import parsedate_to_datetime


def print_citi_html2(soup):
    l = []
    for pre in soup.findAll("pre"):
        l.extend([unicodedata.normalize("NFKD", s) for s in pre.strings])
    return "\n".join(l)


def print_citi_html(email):
    soup = BeautifulSoup(email.get_content(), features="lxml")
    p = soup.find("p")
    if p is None:
        return print_citi_html2(soup)
    s = p.next
    if isinstance(s, NavigableString):
        l = [unicodedata.normalize("NFKD", s)]
    else:
        raise ValueError("weird email")
    for br in p.findAll("br"):
        s = br.next
        if isinstance(s, NavigableString):
            l.append(unicodedata.normalize("NFKD", s))
        elif isinstance(s, Tag) and s.name == "br":
            l.append("\n")
        else:
            raise ValueError
    return "\n".join(l)


def save_emails(update=True):
    """Download new emails that were labeled swaptions."""
    DATA_DIR = Path(os.getenv("DATA_DIR"))

    if update:
        last_history_id = int((DATA_DIR / ".lastHistoryId").read_text())
        existing_msgs = []
    else:
        p = (DATA_DIR / "swaptions").glob("????-??/*")
        existing_msgs = set(str(x).split("_")[1] for x in p if x.is_file())
        last_history_id = None

    gm = GmailMessage()
    for msg in gm.list_msg_ids("swaptions", last_history_id):
        if msg["id"] in existing_msgs:
            continue
        try:
            message = gm.from_id(msg["id"])
            logger.info(message.history_id)
            subject = message["subject"]
            date = parsedate_to_datetime(message["date"])
            if date.tzinfo is None:
                date = date.replace(tzinfo=timezone("utc"))
            date = date.astimezone(timezone("America/New_York"))
            body = message.get_body("plain")
            if body is None:
                try:
                    content = print_citi_html(message.get_body("html"))
                except ValueError:
                    logger.error(
                        "Can't parse HTML email with subject: "
                        f"{subject} and id: {msg['id']}"
                    )
                    continue
            else:
                content = body.get_content()
        except (KeyError, UnicodeDecodeError, AttributeError) as e:
            logger.error("error decoding " + msg["id"])
            continue
        else:
            save_dir = DATA_DIR / "swaptions" / f"{date:%Y-%m}"
            if not save_dir.exists():
                save_dir.mkdir()
            email = save_dir / f"{date:%Y-%m-%d %H-%M-%S}_{msg['id']}"
            with email.open("w") as fh:
                fh.write(subject + "\r\n")
                fh.write(content)
    try:
        new_history_id = message.history_id
        (DATA_DIR / ".lastHistoryId").write_text(message.history_id)
    except UnboundLocalError:
        pass