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_html(email):
    soup = BeautifulSoup(email.get_content(), features="lxml")
    p = soup.find('p')
    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("weird email")
    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"
        existing_msgs = set(str(x).split("_")[1] for x in p.iterdir() 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:
                content = print_citi_html(message.get_body('html'))
            else:
                content = body.get_content()
        except (KeyError, UnicodeDecodeError, AttributeError) as e:
            logger.error("error decoding " + msg['id'])
            continue
        else:
            email = (DATA_DIR / "swaptions" /
                     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