#! /usr/bin/env python

import argparse
import datetime
import ipdb
import os
import pickle
import random
import requests
import stackprinter
import subprocess
import sys

from config import Config
from dbconfig import (
    engine,
    Session,
    scoped_session,
)
from helpers import (
    index_ojects_by_parameter,
    send_mail,
)
from log import log
from mastodon import Mastodon
from models import (
    Accounts,
    Base,
    Hashtags,
    Posts,
    PostTags,
)
from sqlalchemy import (
    func,
    select,
)

from typing import List, Optional, Union

# TESTDATA = "/home/kae/git/urma/hometl.pickle"
#
# Mastodon.create_app(
#     'urma',
#     api_base_url='mastodon.org.uk',
#     to_file='urma_clientcred.secret'
# )

# API_BASE_URL = 'mastodon.org.uk'

# mastodon = Mastodon(client_id = 'urma_clientcred.secret',)
# mastodon.log_in('kae@midnighthax.com', '^ZUaiC8P6vLV49',
#   to_file='urma_usercred.secret')


class MastodonAPI:
    def __init__(self, access_token: str) -> None:
        """
        Initialise access to Mastodon
        """

        self.mastodon = Mastodon(access_token=access_token)
        self.me = self.mastodon.me()

    def get_account_following(self):
        """
        Return a list of account_dicts that we are following
        """

        page1 = self.mastodon.account_following(self.me.id)

        return self.mastodon.fetch_remaining(page1)

    def get_bookmarked(self, since: int) -> List[dict]:
        """
        Return posts bookmarked since id 'since'
        """

        results = []
        data = self.mastodon.bookmarks()
        while data:
            # Add in new data
            results.extend(data)
            # Have we reached minimum id?
            if min([a.id for a in data]) < since:
                break
            # Get more data
            data = self.mastodon.fetch_next(data)

        return results

    def get_hashtag_following(self):
        """
        Return a list of hashtag_dicts that we are following
        """

        page1 = self.mastodon.tag_following(self.me.id)

        return self.mastodon.fetch_remaining(page1)

    def unbookmark(self, post_id: int) -> None:
        """
        Remove bookmark on passed post ID
        """

        log.debug(f"unbookmark({post_id=})")

        _ = self.mastodon.status_unbookmark(post_id)


def update_database() -> None:
    """
    Main loop
    """

    mastapi = MastodonAPI(Config.ACCESS_TOKEN)

    with Session() as session:
        update_followed_accounts(session, mastapi)
        update_followed_hashtags(session, mastapi)

        get_and_process_favourited(session, mastapi)
        get_and_process_bookmarked(session, mastapi)


def get_and_process_bookmarked(session, mastapi):
    """Get newly bookmarked posts and add to db"""

    posts_fetched = 0

    bookmarked = mastapi.mastodon.bookmarks()
    while bookmarked and posts_fetched <= Config.MAX_POSTS_TO_FETCH:
        posts_fetched += len(bookmarked)
        if process_bookmarked_posts(session, bookmarked, mastapi.me.id):
            return
        bookmarked = mastapi.mastodon.fetch_next(bookmarked)


def get_and_process_favourited(session, mastapi):
    """Get newly favourited posts and add to db"""

    posts_fetched = 0

    favourited = mastapi.mastodon.favourites()
    while favourited and posts_fetched <= Config.MAX_POSTS_TO_FETCH:
        posts_fetched += len(favourited)
        if process_favourited_posts(session, favourited, mastapi.me.id):
            return
        favourited = mastapi.mastodon.fetch_next(favourited)


def get_database_name():
    """Return database name as string"""

    with Session() as session:
        dbname = session.bind.engine.url.database

    return dbname


def get_version_string():
    """Return Urma version as string"""

    try:
        return str(
            subprocess.check_output(
                ['git', 'describe'], stderr=subprocess.STDOUT
            )
        ).strip('\'b\\n')
    except subprocess.CalledProcessError as exc_info:
        gitproc = subprocess.Popen(['git', 'rev-parse', 'HEAD'],
                                   stdout=subprocess.PIPE)
        (stdout, _) = gitproc.communicate()
        return stdout.strip()[:7].decode("utf-8")


def process_bookmarked_posts(session: Session,
                             posts: List[Posts], me_id: int) -> bool:
    """
    Process bookmarked posts

    Stop when we find post has already been marked bookmarked.

    Return True if that's why we stopped, else False.
    """

    for post in posts:
        record = _process_post(session, post, me_id)
        # Posts that are favourited and bookmarked are genuine bookmark
        # posts: ignore.
        if record.favourited:
            continue
        if record.bookmarked:
            return True
        else:
            record.bookmarked = True
            # TODO: mastapi.unbookmark(int(post.id))

    return False


def process_favourited_posts(session: Session,
                             posts: List[Posts], me_id: int) -> bool:
    """
    Process favourited posts.

    Stop when we find post has already been marked favourited

    Return True if that's why we stopped, else False.
    """

    for post in posts:
        if post.favourited:
            record = _process_post(session, post, me_id)
            if record.favourited:
                return True
            else:
                record.favourited = True
        else:
            log.debug(
                f"process_favourited_posts({post.id=}) not favourited"
            )

    return False


def _process_post(session: Session, post: Posts, me_id) -> Posts:
    """
    Add passsed post to database
    """

    log.debug(f"{post.id=} processing")

    # Create account record if needed
    log.debug(f"{post.id=} processing {post.account.id=}")
    account_rec = Accounts.get_or_create(session, str(post.account.id))
    if account_rec.username is None:
        log.debug(f"{post.id=} populating new account {post.account.id=}")
        account_rec.username = post.account.username
        account_rec.acct = post.account.acct
        account_rec.display_name = post.account.display_name
        account_rec.bot = post.account.bot
        account_rec.url = post.account.url

    if post.reblog:
        # We're only interesting the boosted post, not this onej
        log.debug(f"{post.id=} {post.reblog.id=}")
        boosted_record = _process_post(session, post.reblog, me_id)
        # Record who bosed the post unless it was us
        if post.account.id == me_id:
            boosted_record.boosting_account_id = None
        else:
            boosted_record.boosting_account_id = account_rec.id
        return boosted_record

    rec = Posts.get_or_create(session, str(post.id))
    if rec.account_id is not None:
        # We already have this post
        log.debug(f"{post.id=} already in db")
        return rec
    else:
        rec.account_id = account_rec.id

    # Create hashtag records as needed
    for tag in post.tags:
        log.debug(f"{post.id=} processing {tag.name=}")
        hashtag = Hashtags.get_or_create(session, tag.name, tag.url)
        rec.hashtags.append(hashtag)

    rec.created_at = post.created_at
    rec.uri = post.uri

    return rec


def report():
    """Print report"""

    print(f"Urma version: {get_version_string()}")
    print(f"Database: {get_database_name()}")
    print(f"Date: {datetime.datetime.now().strftime('%c')}")
    print()

    with Session() as session:
        # Find the most popular hashtags that we don't follow
        print("Hashtags you don't follow that feature in posts you like")
        print("--------------------------------------------------------")
        top_unfollowed_tags = (
            session.execute(
                select(Hashtags, func.count(Hashtags.name))
                .join(PostTags).join(Posts)
                .where(Posts.favourited == 1, Hashtags.followed == 0)
                .group_by(Hashtags.name)
                .order_by(func.count(Hashtags.name).desc())
                .limit(Config.TOP_HASHTAGS_TO_REPORT))
            .all()
        )

        # How many times was each hashtag in a post we didnt' like?
        for (hashtag, like) in top_unfollowed_tags:
            dislike = (
                session.execute(
                    select(func.count(Posts.id))
                    .join(PostTags).join(Hashtags)
                    .where(Posts.favourited == 0, Hashtags.id == hashtag.id)
                ).scalars()
                .all()[0]
            )

            print(
                f"Hashtag {hashtag.name} {like=}, {dislike=} "
                f"({like * 100 / (like + dislike):.2f}% liked)"
            )

        # Find the least popular hashtags that we do follow
        print()
        print("Hashtags you follow that feature in posts you don't like")
        print("--------------------------------------------------------")
        bottom_followed_tags = (
            session.execute(
                select(Hashtags, func.count(Hashtags.name))
                .join(PostTags).join(Posts)
                .where(Posts.favourited == 0, Hashtags.followed == 1)
                .group_by(Hashtags.name)
                .order_by(func.count(Hashtags.name).desc())
                .limit(Config.TOP_HASHTAGS_TO_REPORT))
            .all()
        )

        # How many times was each hashtag in a post we did like?
        for (hashtag, dislike) in bottom_followed_tags:
            like = (
                session.execute(
                    select(func.count(Posts.id))
                    .join(PostTags).join(Hashtags)
                    .where(Posts.favourited == 1, Hashtags.id == hashtag.id)
                ).scalars()
                .all()[0]
            )

            print(
                f"Hashtag {hashtag.name} {like=}, {dislike=} "
                f"({dislike * 100 / (like + dislike):.2f}% disliked)"
            )

        # Find the most popular users that we don't follow
        print()
        print("Users you don't follow that feature in posts you like")
        print("-----------------------------------------------------")
        top_unfollowed_users = (
            session.execute(
                select(Accounts, func.count(Accounts.username))
                .join(Posts)
                .where(Posts.favourited == 1, Accounts.followed == 0)
                .group_by(Accounts.username)
                .order_by(func.count(Accounts.username).desc())
                .limit(Config.TOP_POSTS_TO_REPORT))
            .all()
        )

        # How many times was each user in a post we didnt' like?
        for (user, like) in top_unfollowed_users:
            dislike = (
                session.execute(
                    select(func.count(Posts.id))
                    .join(Accounts)
                    .where(Posts.favourited == 0, Accounts.id == user.id)
                ).scalars()
                .all()[0]
            )

            print(
                f"User {user.username} {like=}, {dislike=} "
                f"({like * 100 / (like + dislike):.2f}% liked)"
            )

        # Find the most unpopular users that we do follow
        print()
        print("Users you follow that feature in posts you don't like")
        print("-----------------------------------------------------")
        bottom_followed_users = (
            session.execute(
                select(Accounts, func.count(Accounts.username))
                .join(Posts)
                .where(Posts.favourited == 0, Accounts.followed == 1)
                .group_by(Accounts.username)
                .order_by(func.count(Accounts.username).desc())
                .limit(Config.TOP_POSTS_TO_REPORT))
            .all()
        )

        # How many times was each user in a post we did like?
        for (user, dislike) in bottom_followed_users:
            like = (
                session.execute(
                    select(func.count(Posts.id))
                    .join(Accounts)
                    .where(Posts.favourited == 1, Accounts.id == user.id)
                ).scalars()
                .all()[0]
            )

            print(
                f"User {user.username} {like=}, {dislike=} "
                f"({dislike * 100 / (like + dislike):.2f}% disliked)"
            )


def update_followed_accounts(session: Session, mastapi: MastodonAPI) -> None:
    """
    Retrieve list of followed accounts and update accounts
    in database to match
    """

    mast_followed_accounts = mastapi.get_account_following()
    mast_followed_accounts_d = index_ojects_by_parameter(
        mast_followed_accounts, "username")

    our_followed_accounts = Accounts.get_followed(session)
    our_followed_accounts_d = index_ojects_by_parameter(
        our_followed_accounts, "username")

    # Add those we are missing
    for username in (
        set(mast_followed_accounts_d.keys()) -
        set(our_followed_accounts_d.keys())
            ):
        account = Accounts.get_or_create(
            session, str(mast_followed_accounts_d[username].id)
        )
        account.followed = True

    # Remove any we no longer follow
    for username in (
        set(our_followed_accounts_d.keys()) -
        set(mast_followed_accounts_d.keys())
    ):
        account = Accounts.get_or_create(
            session, str(our_followed_accounts_d[username].account_id)
        )
        account.followed = False


def update_followed_hashtags(session: Session, mastapi: MastodonAPI) -> None:
    """
    Retrieve list of followed hashtags and update hashtags
    """

    mast_followed_hashtags = mastapi.get_hashtag_following()
    mast_followed_hashtags_d = index_ojects_by_parameter(
        mast_followed_hashtags, "name")

    our_followed_hashtags = Hashtags.get_followed(session)
    our_followed_hashtags_d = index_ojects_by_parameter(
        our_followed_hashtags, "name")

    # Add those we are missing
    for name in (
        set(mast_followed_hashtags_d.keys()) -
        set(our_followed_hashtags_d.keys())
            ):
        hashtag = Hashtags.get_or_create(
            session, name, mast_followed_hashtags_d[name].url)
        hashtag.followed = True

    # Remove any we no longer follow
    for name in (
        set(our_followed_hashtags_d.keys()) -
        set(mast_followed_hashtags_d.keys())
    ):
        hashtag = Hashtags.get_or_create(
            session, name, our_followed_hashtags_d[name].name)
        hashtag.followed = False


if __name__ == "__main__":
    """
    If command line arguments given, carry out requested function and
    exit. Otherwise run full application.
    """
    try:
        Base.metadata.create_all(engine)

        p = argparse.ArgumentParser()
        # Only allow at most one option to be specified
        group = p.add_mutually_exclusive_group()
        group.add_argument('-u', '--update',
                           action="store_true", dest="update_database",
                           default=False, help="Update database from Mastodon")
        group.add_argument('-r', '--report',
                           action="store_true", dest="report",
                           default=False, help="Report")
        args = p.parse_args()

        # Run as required
        if args.update_database:
            log.debug("Updating database")
            update_database()
        elif args.report:
            log.debug("Report")
            report()
        else:
            # For now, default to updating database
            update_database()

    except Exception as exc:

        if os.environ["URMA_ENV"] != "DEVELOPMENT":
            msg = stackprinter.format(exc)
            send_mail(Config.ERRORS_TO, Config.ERRORS_FROM,
                      "Exception from urma", msg)

        print("\033[1;31;47mUnhandled exception starts")
        stackprinter.show(style="darkbg")
        print("Unhandled exception ends\033[1;37;40m")