#!/usr/bin/env python

import os
import argparse

from re import sub
from random import shuffle, randint
from simpleconfigparser import simpleconfigparser
from datetime import datetime, timedelta

import praw
from praw.errors import InvalidUser, InvalidUserPass, RateLimitExceeded
from praw.objects import Comment, Submission

try:
    from loremipsum import get_sentence  # This only works on Python 2
except ImportError:
    if os.name == 'posix':
        try:
            # Try to generate a random string of words
            fh = open('/usr/share/dict/words')
            words = fh.read().splitlines()
            fh.close()
            shuffle(words)

            def get_sentence():
                return ' '.join(words[:randint(50, 150)])
        except IOError:
            def get_sentence():
                return '''I have been Shreddited for privacy!\n\n\
                        https://github.com/x89/Shreddit/'''

parser = argparse.ArgumentParser()
parser.add_argument(
    '-c',
    '--config',
    help="config file to use instead of the default shreddit.cfg"
)
args = parser.parse_args()

config = simpleconfigparser()
if args.config:
    config.read(args.config)
else:
    config.read('shreddit.cfg')

hours = config.getint('main', 'hours')
whitelist = config.get('main', 'whitelist')
whitelist_ids = config.get('main', 'whitelist_ids')
sort = config.get('main', 'sort')
verbose = config.getboolean('main', 'verbose')
clear_vote = config.getboolean('main', 'clear_vote')
trial_run = config.getboolean('main', 'trial_run')
edit_only = config.getboolean('main', 'edit_only')
item = config.get('main', 'item')
whitelist_distinguished = config.getboolean('main', 'whitelist_distinguished')
whitelist_gilded = config.getboolean('main', 'whitelist_gilded')
_user = config.get('main', 'username')
_pass = config.get('main', 'password')

r = praw.Reddit(user_agent="shreddit/3.1")


def login(user=None, password=None):
    try:
        if user and password:
            r.login(_user, _pass)
        else:
            r.login()  # Let the user supply details
    except InvalidUser as e:
        raise InvalidUser("User does not exist.", e)
    except InvalidUserPass as e:
        raise InvalidUserPass("Specified an incorrect password.", e)
    except RateLimitExceeded as e:
        raise RateLimitExceeded("You're doing that too much.", e)

if not r.is_logged_in():
    login(user=_user, password=_pass)

if verbose:
    print("Logged in as {user}".format(user=r.user))

if verbose:
    print("Deleting messages before {time}.".format(
        time=datetime.now() - timedelta(hours=hours))
    )

whitelist = [y.strip().lower() for y in whitelist.split(',')]
whitelist_ids = [y.strip().lower() for y in whitelist_ids.split(',')]

if verbose and whitelist:
    print("Keeping messages from subreddits {subs}".format(
        subs=', '.join(whitelist))
    )

things = []
if item == "comments":
    things = r.user.get_comments(limit=None, sort=sort)
elif item == "submitted":
    things = r.user.get_submitted(limit=None, sort=sort)
elif item == "overview":
    things = r.user.get_overview(limit=None, sort=sort)
else:
    raise Exception("Your deletion section is wrong")

for thing in things:
    thing_time = datetime.fromtimestamp(thing.created_utc)
    # Delete things after after_time
    after_time = datetime.utcnow() - timedelta(hours=hours)
    if thing_time > after_time:
        continue
    # For edit_only we're assuming that the hours aren't altered.
    # This saves time when deleting (you don't edit already edited posts).
    if edit_only:
        end_time = after_time - timedelta(hours=hours)
        if thing_time < end_time:
                continue

    if str(thing.subreddit).lower() in whitelist or \
       thing.id in whitelist_ids:
        continue

    if trial_run:
        # Don't actually perform any actions
        next
    if whitelist_distinguished and thing.distinguished:
        next
    if whitelist_gilded and thing.gilded:
        next

    if clear_vote:
        thing.clear_vote()
    if isinstance(thing, Submission):
        if verbose:
            print(u'Deleting submission: #{id} {url}'.format(
                id=thing.id,
                url=thing.url)
            )
    elif isinstance(thing, Comment):
        replacement_text = get_sentence()
        if verbose:
            msg = '/r/{3}/ #{0} with:\n\t"{1}" to\n\t"{2}"'.format(
                thing.id,
                sub(b'\n\r\t', ' ', thing.body[:78].encode('utf-8')),
                replacement_text[:78],
                thing.subreddit
            )
            if edit_only:
                print('Editing {msg}'.format(msg=msg))
            else:
                print('Editing and deleting {msg}'.format(msg=msg))
        thing.edit(replacement_text)
    if not edit_only:
        thing.delete()