# -*- Encoding: utf-8 -*-
###
# Copyright (c) 2006-2007 Dennis Kaarsemaker
# Copyright (c) 2008-2010 Terence Simpson
# Copyright (c) 2018-     Krytarik Raido
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of version 2 of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
###

from supybot.commands import *
import supybot.ircmsgs as ircmsgs
import supybot.callbacks as callbacks
import supybot.registry as registry
import supybot.ircdb as ircdb
import supybot.conf as conf
import supybot.utils as utils
import supybot.ircutils as ircutils
import supybot.world as world
import sys, os, re, hashlib, random
import sqlite3, datetime, time

_stripNickChars = """!"#$%&'()*+,./:;<=>?@~"""
def stripNick(nick):
    while nick and nick[-1] in _stripNickChars:
        nick = nick[:-1]
    return nick

def defaultIgnored(hostmask):
    if not conf.supybot.defaultIgnore():
        return False
    try:
        user = ircdb.users.getUser(hostmask)
    except KeyError:
        return True
    return False

def checkIgnored(hostmask, channel):
    try:
        user = ircdb.users.getUser(hostmask)
        try:
            if user._checkCapability('trusted'):
                return False
        except KeyError:
            pass
        if user.ignore:
            return True
    except KeyError:
        pass
    if ircdb.ignores.checkIgnored(hostmask):
        return True
    if channel:
        c = ircdb.channels.getChannel(channel)
        if c.checkIgnored(hostmask):
            return True
    return False

def checkAddressed(text, channel):
    if channel:
        if text[0] in str(conf.supybot.reply.whenAddressedBy.chars.get(channel)):
            return True
    elif text[0] in conf.supybot.reply.whenAddressedBy.chars():
        return True
    return False

# Simple wrapper class for factoids
class Factoid:
    def __init__(self, name, value, author=None, added=None,
            editor=None, edited=None, popularity=None):
        self.name = name;     self.value = value
        self.author = author; self.added = added
        self.editor = editor; self.edited = edited
        self.popularity = popularity

class FactoidSet:
    def __init__(self):
        self.global_primary = self.global_secondary = \
        self.channel_primary = self.channel_secondary = None

# Repeat filtering message queue
msgcache = {}
def queue(irc, target, msg):
    if world.testing:
        # don't mess up testcases
        irc.reply(msg, to=target, private=True)
        return
    now = time.time()
    for m in list(msgcache.keys()):
        if msgcache[m] < now - 30:
            msgcache.pop(m)
    for m in msgcache:
        if m[0] == irc and m[1] == target:
            oldmsg = m[2]
            if oldmsg.endswith(msg):
                break
            if msg.endswith(oldmsg) and msg[:-len(oldmsg)].endswith(': '):
                msg = msg[:-len(oldmsg)] + 'Please see above'
    else:
        msgcache[(irc, target, msg)] = now
        irc.reply(msg, to=target, private=True)

def capab(prefix, capability):
    # too bad people don't use supybot's own methods,
    # it would save me the trouble of hacking this up
    if world.testing:
        # we're running a testcase, return always True
        return True
    # Capability hierarchy #
    if capability == "editfactoids":
        if capab(prefix, "addeditors"):
            return True
    elif capability == "addeditors":
        if capab(prefix, "admin"):
            return True
    elif capability == "admin":
        if capab(prefix, "owner"):
            return True
    # Check capability #
    try:
        user = ircdb.users.getUser(prefix)
    except KeyError:
        return False
    if capability in list(user.capabilities):
        return True
    return False

def get_factoid_label(n, v):
    if '<alias>' in v:
        n += '@' + v[v.find('<alias>')+7:].strip()
    if v.startswith('<deleted>'):
        n += '*'
    return n

def get_alias_label(n, v):
    if v.startswith('<deleted>'):
        n += '*'
    return n

# This regexp should match most URLs in the format protocol://(domain|ip adress)
# and the special case when there's no protocol but domain starts with www.
# We do this so we can filter obvious requests with spam in them
octet = r'(?:2(?:[0-4]\d|5[0-5])|1\d\d|\d{1,2})' # 0 - 255
ip_address = r'%s(?:\.%s){3}' % (octet, octet)   # 0.0.0.0 - 255.255.255.255
# Base domain regex off RFC 1034 and 1738
label = r'[0-9a-z][-0-9a-z]*[0-9a-z]?'
domain = r'%s(?:\.%s)*\.[a-z][-0-9a-z]*[a-z]?' % (label, label) # like www.ubuntu.com
# complete regexp
urlRe = re.compile(r'(?:\w+://(?:%s|%s)|www\.%s)' % (domain, ip_address, domain), re.I)

def checkUrl(s):
    """Check if string contains something like a URL"""
    return bool(urlRe.search(s))

class DbWrapper(object):
    def __init__(self, db, name):
        self.db = db
        self.name = name
        self.time = time.time()

class Encyclopedia(callbacks.Plugin):
    """!factoid: show factoid"""
    def __init__(self, irc):
        self.__parent = super(Encyclopedia, self)
        self.__parent.__init__(irc)
        self.databases = {}
        self.times = {}
        self.edits = {}
        self.alert = False
        self.defaultIrc = irc

    class editor(callbacks.Commands):
        def add(self, irc, msg, args, name):
            """<name>

            Adds the user with the name <name> to the list of editors.
            """
            if not capab(msg.prefix, 'addeditors'):
                irc.errorNoCapability('addeditors')
                return
            try:
                user = ircdb.users.getUser(name)
                user.addCapability('editfactoids')
                irc.replySuccess()
            except:
                irc.error('User %s is not registered' % name)
        add = wrap(add, ['otherUser'])

        def remove(self, irc, msg, args, name):
            """<name>

            Removes the user with the name <name> from the list of editors.
            """
            if not capab(msg.prefix, 'addeditors'):
                irc.errorNoCapability('addeditors')
                return
            try:
                user = ircdb.users.getUser(name)
                user.removeCapability('editfactoids')
                irc.replySuccess()
            except:
                irc.error('User %s is not registered or not an editor' % name)
        remove = wrap(remove, ['otherUser'])

    def editors(self, irc, msg, args):
        """takes no arguments

        Lists all the users who are in the list of editors.
        """
        irc.reply(', '.join([u.name for u in list(ircdb.users.users.values()) if capab(u.name, 'editfactoids')]), private=True)
    editors = wrap(editors)

    def moderators(self, irc, msg, args):
        """takes no arguments

        Lists all the users who can add users to the list of editors.
        """
        irc.reply(', '.join([u.name for u in list(ircdb.users.users.values()) if capab(u.name, 'addeditors')]), private=True)
    moderators = wrap(moderators)

    def get_target(self, irc, nick, text, target):
        ret, retmsg = text, ''
        orig_target = target

        # Test for factoid creation/edit before continuing
        if re.match(r'\S+\s+is(\s+|\s*<(reply|alias|sed)>\s*)\S+', text, re.I):
            return ret, target, retmsg

        if '|' in text:
            retmsg = text[text.find('|')+1:].lstrip('|').strip()
            ret = text[:text.find('|')].strip()
            if retmsg:
                if retmsg.lower() == "me":
                    retmsg = nick
                retmsg = "%s: " % retmsg

        elif '>' in text:
            target = text[text.find('>')+1:].lstrip('>').strip()
            ret = text[:text.find('>')].strip()
            if target:
                # Take the first "nick" and strip off bad chars
                target = stripNick(target.split()[0])
                if target.lower() == "me":
                    target = nick
                retmsg = "<%s> wants you to know: " % nick

        else:
            match = re.match(r'^tell\s+(?P<target>\S+)\s+about\s+(?P<ret>.+)$', text, re.I)
            if match:
                target = match.group('target')
                ret = match.group('ret')
                if target.lower() == "me":
                    target = nick
                retmsg = "<%s> wants you to know: " % nick

        if target.lower() != orig_target.lower() and irc.isChannel(target):
            target = orig_target
            retmsg = "(Forwarding to channels is not permitted) "
        elif nick.lower() in (target.lower(), retmsg[:-2].lower()) \
                and nick.lower() != orig_target.lower():
            target = nick
            retmsg = "(In the future, please use a private message to investigate) "

        return ret, target, retmsg

    def get_db(self, channel):
        db = self.registryValue('database', channel)
        if channel in self.databases \
                and (self.databases[channel].time < time.time() - 3600 \
                or self.databases[channel].name != db):
            self.databases[channel].db.close()
            self.databases.pop(channel)
        if channel not in self.databases:
            self.databases[channel] = DbWrapper(
                sqlite3.connect(os.path.join(self.registryValue('datadir'), '%s.db' % db)), db)
        return self.databases[channel].db

    def get_factoids(self, name, channel, display=None):
        factoids = FactoidSet()
        if not display or display == 'alias':
            deleted = False
        else:
            deleted = True
        factoids.global_primary   = self.get_single_factoid(channel, name, deleted)
        factoids.global_secondary = self.get_single_factoid(channel, name + '-also', deleted)
        if channel and not display:
            factoids.channel_primary   = self.get_single_factoid(channel, name + '-' + channel.lower(), deleted)
            factoids.channel_secondary = self.get_single_factoid(channel, name + '-' + channel.lower() + '-also', deleted)
        if not display:
            self.increment_factoid_popularity(factoids, channel)
            factoids.global_primary   = self.resolve_alias(channel, factoids.global_primary)
            factoids.global_secondary = self.resolve_alias(channel, factoids.global_secondary)
            if channel:
                factoids.channel_primary   = self.resolve_alias(channel, factoids.channel_primary)
                factoids.channel_secondary = self.resolve_alias(channel, factoids.channel_secondary)
        elif display == 'info':
            factoids.global_primary   = self.factoid_info(channel, factoids.global_primary)
            factoids.global_secondary = self.factoid_info(channel, factoids.global_secondary)
            if channel:
                factoids.channel_primary   = self.factoid_info(channel, factoids.channel_primary)
                factoids.channel_secondary = self.factoid_info(channel, factoids.channel_secondary)
        return factoids

    def increment_factoid_popularity(self, factoids, channel):
        for order in ('primary', 'secondary'):
            for loc in ('channel', 'global'):
                key = '%s_%s' % (loc, order)
                if getattr(factoids, key):
                    factoid = getattr(factoids, key)
                    if isinstance(factoid, Factoid):
                        db = self.get_db(channel)
                        cur = db.cursor()
                        cur.execute("UPDATE facts SET popularity = ? WHERE name = ?", (factoid.popularity+1, factoid.name))
                        db.commit()
                        break

    def get_single_factoid(self, channel, name, deleted=False):
        db = self.get_db(channel)
        cur = db.cursor()
        if deleted:
            cur.execute("SELECT name, value, author, added, editor, edited, popularity FROM facts WHERE name = ?", (name.lower(),))
        else:
            cur.execute("SELECT name, value, author, added, editor, edited, popularity FROM facts WHERE name = ? AND value NOT LIKE '<deleted>%%'", (name.lower(),))
        factoids = cur.fetchall()
        if factoids:
            return Factoid(*factoids[0])

    def resolve_alias(self, channel, factoid, loop=0):
        if not factoid:
            return
        if loop >= 10:
            return "Error: Infinite <alias> loop detected"
        if factoid.name in self.registryValue('alert', channel):
            self.alert = True
        if factoid.value.startswith('<alias>'):
            alias_name = factoid.value[7:].strip()
            factoids = self.get_factoids(alias_name, channel, display='alias')
            for x in ('channel_primary', 'global_primary'):
                if getattr(factoids, x):
                    return self.resolve_alias(channel, getattr(factoids, x), loop+1)
            return "Error: Unresolvable <alias> to '%s'" % alias_name
        else:
            return factoid

    def factoid_info(self, channel, factoid):
        if not factoid:
            return
        ret = [get_factoid_label(factoid.name, factoid.value)]
        aliases = self.get_aliases(channel, factoid)
        if aliases:
            ret.append("aliases: %s" % ', '.join([get_alias_label(x[0], x[1]) for x in aliases]))
        else:
            ret.append("no aliases")
        # Author info
        ret.append("added by %s on %s" % (factoid.author[:factoid.author.find('!')], factoid.added[:factoid.added.rfind('.')]))
        if factoid.editor:
            ret.append("last edited by %s on %s" % (factoid.editor[:factoid.editor.find('!')], factoid.edited[:factoid.edited.rfind('.')]))
        # Popularity info
        ret.append("requested %d times" % factoid.popularity)
        return ' - '.join(ret)

    def get_aliases(self, channel, factoid):
        db = self.get_db(channel)
        cur = db.cursor()
        cur.execute("SELECT name, value FROM facts WHERE value LIKE ?", ('%%<alias>_%s' % factoid.name,))
        data = cur.fetchall()
        return data

    def check_aliases(self, channel, factoid, oldvalue, etype):
        now = time.time()
        for e in list(self.edits.keys()):
            if self.edits[e] < now - 10:
                self.edits.pop(e)
        # Was the old value an alias?
        if etype == 'edit' and oldvalue.startswith('<alias>') \
                and not factoid.value.startswith('<alias>'):
            if factoid.name not in self.edits:
                self.edits[factoid.name] = now
                return "You are editing an alias.  Please repeat the edit command within the next 10 seconds to confirm"
        # Do some alias resolving
        if factoid.value.startswith('<alias>') and etype != 'delete':
            alias_name = factoid.value[7:].strip()
            alias = self.get_single_factoid(channel, alias_name)
            if not alias:
                return "Factoid '%s' does not exist" % alias_name
            alias = self.resolve_alias(channel, factoid)
            if not isinstance(alias, Factoid):
                return alias

    def inFilter(self, irc, msg):
        if not (msg.prefix and msg.args):
            return msg
        if not ircutils.isUserHostmask(msg.prefix):
            return msg
        if not defaultIgnored(msg.prefix):
            return msg
        if checkIgnored(msg.prefix, msg.channel):
            return msg
        if msg.command == "PRIVMSG":
            self.doPrivmsg(irc, msg)
        return msg

    def doPrivmsg(self, irc, msg):
        queue_msg = True # Queue message or send directly
        def noqueue(irc, target, msg):
            irc.reply(msg, to=target, private=True)
        def myqueue(irc, target, msg):
            (queue if queue_msg else noqueue)(irc, target, msg)

        # Filter CTCP
        if chr(1) in msg.args[1]:
            return

        if sys.version_info < (3,0):
            text = msg.args[1].decode('utf-8').strip()
        else:
            text = msg.args[1].strip()
        if not text:
            return
        target = msg.args[0]
        channel = msg.channel

        if checkAddressed(text, channel):
            return
        if not self.registryValue('enabled', channel):
            return

        if not channel:
            cmd = text.split()[0].lower()
            for c in irc.callbacks:
                if c.isCommandMethod(cmd):
                    return

        prefixchar = self.registryValue('prefixchar', channel)
        if text[0] == prefixchar:
            text = text[1:].strip()
        elif re.match(r'^%s[\W\s]\s*%s' % (re.escape(irc.nick), re.escape(prefixchar)), text, re.I):
            text = re.sub(r'^%s[\W\s]\s*%s\s*' % (re.escape(irc.nick), re.escape(prefixchar)), '', text, flags=re.I)
        elif channel:
            return
        if not text:
            return
        if text.split()[0].lower() in self.registryValue('ignores', channel):
            return

        display = None # Set display type
        edit = None
        if not channel:
            target = msg.nick

        # Get display type
        while text and text[0] in '-+':
            if text[0] == '-':
                display = 'info'
            elif text[0] == '+':
                display = 'raw'
            text = text[1:].strip()
        if not text:
            return

        irc = callbacks.ReplyIrcProxy(irc, msg)
        ret, retmsg = '', ''

        # Now switch between actions
        if display:
            ret = self.factoid_lookup(text, channel, msg.nick, display)
        else:
            term = self.get_target(irc, msg.nick, text, target)
            lower_term = term[0].lower()

            if lower_term == "search": # Usage info for the !search command
                ret = "Search factoids for term: !search <term>"
                target = term[1]
                retmsg = term[2]
            elif re.match(r"^seen\b", lower_term): # Some people expect a '!seen <nick>' command
                ret = "I have no seen command"
                retmsg = "%s: " % msg.nick if term[2] else '' # Redirect back at the caller, rather than the target
            elif lower_term.startswith("google "): # Some people expect a '!google <term...>' command
                ret = "I have no google command, use https://www.google.com/"
                retmsg = "%s: " % msg.nick if term[2] else '' # Redirect back at the caller, rather than the target
            elif re.match(r"^what'?s?\b", lower_term): # Try and catch people saying "ubottu: what is ...?"
                ret = "I am only a bot, please don't think I'm intelligent :)"
                retmsg = "%s: " % msg.nick if channel else ''

            # Lookup, search or edit?
            elif lower_term.startswith('search '):
                ret = self.search_factoid(text[7:].strip(), channel)
            elif lower_term.startswith('delete '):
                edit = 'delete'
            elif re.match(r'^no[\s,]+[^|\s]+[^|]*?\s+is(\s+|\b)\S+', text, re.I) \
                    or re.match(r'^[^|\s]+[^|]*?\s*(\s+is\s*<sed>|=~|~=)\s*\S+', text, re.I) \
                    or lower_term.startswith(('forget ', 'unforget ')):
                edit = 'edit'
            elif re.match(r'^[^|\s]+[^|]*?\s+is(\s+|\b)\S+', text, re.I):
                edit = 'add'
            else:
                text, target, retmsg = term
                ret = self.factoid_lookup(text, channel, msg.nick, display)

        if edit:
            check = getattr(self, 'factoid_%s_check' % edit)(text, channel, msg.nick)
            if not isinstance(check, tuple):
                ret = check
            elif not (capab(msg.prefix, 'editfactoids') \
                    or (channel in self.registryValue('editchannel') \
                    and capab(msg.prefix, 'restricted-editor'))):
                if len(check[1].name.split()) > 4:
                    ret = "I am only a bot, please don't think I'm intelligent :)"
                    retmsg = "%s: " % msg.nick if channel else ''
                else:
                    relaychan = self.registryValue('relaychannel', channel)
                    if channel and channel == relaychan:
                        irc.reply("%s: Your edit request will be attended to as soon as possible.  "  % msg.nick
                                  + "Thank you for your attention to detail", to=channel)
                    else:
                        irc.reply("Your edit request has been forwarded to %s.  " % relaychan
                                  + "Thank you for your attention to detail", private=True)
                        irc.reply("In %s, %s said: %s" % (msg.args[0], msg.nick, msg.args[1]), to=relaychan)
                    self.log_request(check[0], check[1], channel, msg.prefix)
                    return
            else:
                queue_msg = False
                getattr(self, 'factoid_%s' % edit)(check[1], channel, msg.prefix)
                ret = check[2]

        if not ret:
            if len(text.split()) > 4:
                ret = "I am only a bot, please don't think I'm intelligent :)"
                retmsg = "%s: " % msg.nick if channel else ''
            else:
                ret = self.registryValue('notfoundmsg')
                if ret.count('%') == ret.count('%s') == 1:
                    if sys.version_info < (3,0):
                        ret = ret % repr(text).lstrip('u')
                    else:
                        ret = ret % repr(text)
                if not channel or self.registryValue('privateNotFound', channel):
                    myqueue(irc, msg.nick, ret)
                else:
                    myqueue(irc, channel, ret)
                return

        if not isinstance(ret, list):
            myqueue(irc, target, retmsg + ret)
        else:
            if self.alert:
                if channel and not channel.endswith('bots'):
                    irc.reply('%s called the ops in %s (%s)' % (msg.nick, msg.args[0], retmsg),
                              to=self.registryValue('relayChannel', channel))
                self.alert = False
                if retmsg and checkUrl(retmsg):
                    # !ops factoid called with a URL, most likely spam
                    return
            if channel and not irc.isChannel(target) \
                    and target in irc.state.channels[channel].users:
                myqueue(irc, channel, "%s: Please see my private message" % target)
            myqueue(irc, target, retmsg + ret[0])
            for r in ret[1:]:
                myqueue(irc, target, r)

    def doPart(self, irc, msg):
        if len(msg.args) < 2 or not msg.args[1].startswith('requested by'):
            return
        channel, reason = msg.args
        reason = reason[reason.find('(')+1:-1] # get the text between ()
        self._forcedFactoid(irc, channel, msg.nick, reason)

    def doKick(self, irc, msg):
        channel, nick, reason = msg.args
        self._forcedFactoid(irc, channel, nick, reason)

    def _forcedFactoid(self, irc, channel, nick, reason):
        if not self.registryValue('forcedFactoid', channel):
            return
        factoidRe = re.compile(r'%s\w+\b' % re.escape(self.registryValue('prefixchar', channel)))
        factoids = factoidRe.findall(reason)
        if not factoids:
            return
        L = []
        for fact in factoids:
            L.extend(self.factoid_lookup(fact[1:], channel, nick))
        for s in L:
            irc.reply(s, to=nick, private=True)

    def factoid_delete(self, factoid, channel, editor):
        edited = str(datetime.datetime.utcnow())
        self.log_edit('delete', factoid, channel, editor, edited)
        db = self.get_db(channel)
        cs = db.cursor()
        cs.execute("DELETE FROM facts WHERE name = ?", (factoid.name,))
        db.commit()

    def factoid_delete_check(self, text, channel, editor):
        if not text.lower().startswith('delete '):
            return
        name = text[7:].strip()
        factoid = self.get_single_factoid(channel, name, deleted=True)
        if not factoid:
            return "I know nothing about '%s' yet, %s" % (name, editor)
        aliases = self.get_aliases(channel, factoid)
        if aliases:
            return "Factoid '%s' has aliases still, %s" % (name, editor)
        retmsg = "I'll delete that, %s" % editor
        ret = self.check_aliases(channel, factoid, None, 'delete')
        if ret:
            return ret
        return 'delete', factoid, retmsg

    def factoid_edit(self, factoid, channel, editor):
        edited = str(datetime.datetime.utcnow())
        self.log_edit('edit', factoid, channel, editor, edited)
        db = self.get_db(channel)
        cs = db.cursor()
        cs.execute("UPDATE facts SET value = ?, editor = ?, edited = ? WHERE name = ?",
                   (factoid.value, editor, edited, factoid.name))
        db.commit()

    def factoid_edit_check(self, text, channel, editor):
        factoid = value = oldvalue = retmsg = None
        etype = 'edit'
        if text.lower()[:3] in ('no ', 'no,'):
            match = re.match(r'^no[\s,]+(?P<name>\S+.*?)\s+is(?:\s+|\b)(?P<value>.*?\S+)$', text, re.I)
            if not match:
                return
            name = match.group('name')
            value = match.group('value')
            factoid = self.get_single_factoid(channel, name)
            if not factoid:
                return "I know nothing about '%s' yet, %s" % (name, editor)
            if value == factoid.value:
                return "Nothing changed there"
            oldvalue = factoid.value
            factoid.value = value
            retmsg = "I'll remember that, %s" % editor

        elif text.lower().startswith('forget '):
            etype = 'forget'
            name = text[7:].strip()
            factoid = self.get_single_factoid(channel, name)
            if not factoid:
                return "I know nothing about '%s' yet, %s" % (name, editor)
            aliases = self.get_aliases(channel, factoid)
            if aliases:
                return "Factoid '%s' has aliases still, %s" % (name, editor)
            oldvalue = factoid.value
            factoid.value = '<deleted>%s' % factoid.value
            retmsg = "I'll forget that, %s" % editor

        elif text.lower().startswith('unforget '):
            etype = 'unforget'
            name = text[9:].strip()
            factoid = self.get_single_factoid(channel, name, deleted=True)
            if not factoid:
                return "I know nothing about '%s' at all, %s" % (name, editor)
            if not factoid.value.startswith('<deleted>'):
                return "Factoid '%s' is not deleted yet, %s" % (factoid.name, editor)
            oldvalue = factoid.value
            factoid.value = factoid.value[9:]
            retmsg = "I suddenly remember '%s' again, %s" % (factoid.name, editor)

        else:
            match = re.match(r'^(?P<name>\S+.*?)\s*(?:\s+is\s*<sed>|=~|~=)\s*(?P<regex>.*?\S+)$', text, re.I)
            if not match:
                return
            # Split into name and regex
            name = match.group('name')
            regex = match.group('regex')
            # Edit factoid
            factoid = self.get_single_factoid(channel, name)
            if not factoid:
                return "I know nothing about '%s' yet, %s" % (name, editor)
            # Grab the regex
            if regex.startswith('s'):
                regex = regex[1:]
            if regex[-1] != regex[0]:
                return "Missing end delimiter"
            if regex.count(regex[0]) > 3:
                return "Too many delimiters"
            if regex.count(regex[0]) < 3:
                return "Not enough delimiters"
            regex, replace = regex[1:-1].split(regex[0])
            try:
                regex = re.compile(regex)
            except:
                return "Malformed regex"
            value = regex.sub(replace, factoid.value, 1)
            if value == factoid.value:
                return "Nothing changed there"
            oldvalue = factoid.value
            factoid.value = value
            retmsg = "I'll remember that, %s" % editor

        ret = self.check_aliases(channel, factoid, oldvalue, etype)
        if ret:
            return ret
        return 'edit', factoid, retmsg

    def factoid_add(self, factoid, channel, editor):
        edited = str(datetime.datetime.utcnow())
        self.log_edit('add', factoid, channel, editor, edited)
        db = self.get_db(channel)
        cs = db.cursor()
        cs.execute("INSERT INTO facts (name, value, author, added) VALUES (?, ?, ?, ?)",
                   (factoid.name, factoid.value, editor, edited))
        db.commit()

    def factoid_add_check(self, text, channel, editor):
        match = re.match(r'^(?P<name>\S+.*?)\s+is(?:\s+|\b)(?P<value>.*?\S+)$', text, re.I)
        if not match:
            return
        name = match.group('name').lower()
        if re.match(r'.*<(reply|alias|sed)>.*', name):
            return "You likely don't want this, %s" % editor
        value = match.group('value')
        if value.startswith(('also ', 'also:')):
            name += '-also'
            value = value[5:].strip()
            if not value:
                return
        if self.get_single_factoid(channel, name, deleted=True):
            return "But '%s' already means something else!" % name
        factoid = Factoid(name, value)
        retmsg = "I'll remember that, %s" % editor
        ret = self.check_aliases(channel, factoid, None, 'add')
        if ret:
            return ret
        return 'add', factoid, retmsg

    def factoid_lookup(self, text, channel, nick, display=None):
        def expand(value):
            for k in sorted(list(expandos.keys()), reverse=True):
                value = value.replace(k, expandos[k])
            return value

        expandos = {
            '$who': nick, '$nick': self.defaultIrc.nick, '$chan': channel or self.defaultIrc.nick,
            '$curStable': self.registryValue('curStable'), '$curStableLower': self.registryValue('curStable').lower(),
            '$curStableLong': self.registryValue('curStableLong'), '$curStableNum': self.registryValue('curStableNum'),
            '$curLTS': self.registryValue('curLTS'), '$curLTSLower': self.registryValue('curLTS').lower(),
            '$curLTSLong': self.registryValue('curLTSLong'), '$curLTSNum': self.registryValue('curLTSNum'),
            '$curDevel': self.registryValue('curDevel'), '$curDevelLower': self.registryValue('curDevel').lower(),
            '$curDevelLong': self.registryValue('curDevelLong'), '$curDevelNum': self.registryValue('curDevelNum')
        }

        factoids = self.get_factoids(text, channel, display=display)
        ret = []
        for order in ('primary', 'secondary'):
            for loc in ('channel', 'global'):
                key = '%s_%s' % (loc, order)
                if getattr(factoids, key):
                    factoid = getattr(factoids, key)
                    if not isinstance(factoid, Factoid):
                        ret.append(factoid)
                    elif display == 'raw':
                        ret.append(factoid.value)
                    elif factoid.value.startswith('<reply>'):
                        ret.append(expand(factoid.value[7:].strip()))
                    elif order == 'secondary':
                        ret.append(expand(factoid.value))
                    else:
                        name = factoid.name
                        if '-#' in name:
                            name = name[:name.rfind('-#')]
                        ret.append('%s is %s' % (name, expand(factoid.value)))
                    if not display == 'info':
                        break
        return ret

    def log_edit(self, etype, factoid, channel, editor, edited):
        db = self.get_db(channel)
        cs = db.cursor()
        cs.execute("INSERT INTO log (type, name, value, author, added) VALUES (?, ?, ?, ?, ?)",
                   (etype, factoid.name, factoid.value, editor, edited))
        db.commit()

    def log_request(self, rtype, factoid, channel, requester):
        db = self.get_db(channel)
        cur = db.cursor()
        cur.execute("SELECT type, value FROM requests WHERE name = ?", (factoid.name,))
        items = cur.fetchall()
        for i in items:
            if i[0] == rtype and i[1] == factoid.value:
                return
        cur.execute("INSERT INTO requests (type, name, value, requester, requested) VALUES (?, ?, ?, ?, ?)",
                    (rtype, factoid.name, factoid.value, requester, str(datetime.datetime.utcnow())))
        db.commit()

    def search_factoid(self, text, channel):
        keys = text.split()[:5]
        db = self.get_db(channel)
        cur = db.cursor()
        qterms, values, ret = '', [], []
        for k in keys:
            if qterms:
                qterms += ' AND '
            qterms += '(name LIKE ? OR value LIKE ? OR value LIKE ?)'
            values.extend(['%%%s%%' % k.lower(), '%%%s%%' % k, '%%%s%%' % k.lower()])
        cur.execute("SELECT name, value FROM facts WHERE %s ORDER BY popularity DESC" % qterms, values)
        res = cur.fetchall()
        for r in res:
            ret.append(get_factoid_label(r[0], r[1]))
        if not ret:
            return "None found"
        return 'Found: %s' % ', '.join(ret)

    def sync(self, irc, msg, args, channel):
        """[<channel>]

        Downloads a copy of the database from the remote server.
        Set the server with the channel variable supybot.plugins.Encyclopedia.remotedb.
        If <channel> is not set, it will default to the channel
        the command is given in or the global value.
        """
        if not capab(msg.prefix, "owner"):
            irc.errorNoCapability("owner")
            return
        remotedb = self.registryValue('remotedb', channel)
        if not remotedb:
            return

        def download_database(location, dpath):
            """Download the database located at location to path dpath"""
            tmp_db = "%s%stmp" % (dpath, os.extsep)
            data = utils.web.getUrl(location)
            fd = open(tmp_db, 'w')
            fd.write(data) # Download to a temporary file
            fd.close()
            # Do some checking to make sure we have an SQLite database
            fd = open(tmp_db, 'rb')
            check = fd.read(15)
            if check == 'SQLite format 3': # OK, rename to dpath
                os.rename(tmp_db, dpath)
                try:
                    self.databases[channel].db.close()
                except:
                    pass
                try:
                    self.databases.pop(channel)
                except:
                    pass
            else: # Remove the temporary file and raise an error
                os.remove(tmp_db)
                raise RuntimeError("Downloaded file was not an SQLite 3 database")

        db = self.registryValue('database', channel)
        if not db:
            if channel:
                irc.error("I don't have a database set for %s" % channel)
                return
            irc.error("There is no global database set, use 'config supybot.plugins.Encyclopedia.database <database>' to set it")
            return
        if not remotedb:
            if channel:
                irc.error("I don't have a remote database set for %s" % channel)
                return
            irc.error("There is no global remote database set, use 'config supybot.plugins.Encyclopedia.remotedb <url>' to set it")
            return
        dbpath = os.path.join(self.registryValue('datadir'), '%s.db' % db)
        # We're moving files and downloading, lots can go wrong so use lots of try blocks
        try:
            os.rename(dbpath, "%s.bak" % dbpath)
        except OSError:
            # File doesn't exist yet, so nothing to back up
            pass
        except Exception as e:
            self.log.error("Encyclopedia: Could not rename %s to %s.bak" % (dbpath, dbpath))
            self.log.error('Encyclopedia: %s' % utils.exnToString(e))
            irc.error("Internal error, see log")
            return

        try:
            # Downloading can take some time, let the user know we're doing something
            irc.reply("Attemting to download database")
            download_database(remotedb, dbpath)
            irc.replySuccess()
        except Exception as e:
            self.log.error("Encyclopedia: Could not download %s to %s" % (remotedb, dbpath))
            self.log.error('Encyclopedia: %s' % utils.exnToString(e))
            irc.error("Internal error, see log")
            os.rename("%s.bak" % dbpath, dbpath)
            return
    sync = wrap(sync, [optional("channel")])

    def lookup(self, irc, msg, args, author, channel):
        """[<author>] [<channel>]

        Looks up factoids created or edited by <author>,
        <author> defaults to you.
        """
        if not capab(msg.prefix, "editfactoids"):
            irc.errorNoCapability("editfactoids")
            return
        if not author:
            author = msg.prefix
        if '!' in author:
            author = author[:author.find('!')]
        db = self.get_db(channel)
        cur = db.cursor()
        auth_ret, edit_ret = [], []
        cur.execute("SELECT name, value FROM facts WHERE author LIKE ? ORDER BY popularity DESC", ('%s%%' % author,))
        auth_res = cur.fetchall()
        cur.execute("SELECT name, value FROM facts WHERE editor LIKE ? AND author NOT LIKE ? ORDER BY popularity DESC", ('%s%%' % author, '%s%%' % author))
        edit_res = cur.fetchall()

        for r in auth_res:
            auth_ret.append(get_factoid_label(r[0], r[1]))

        for r in edit_res:
            edit_ret.append(get_factoid_label(r[0], r[1]))

        if not auth_ret:
            auth_rmsg = "Authored: None found"
        else:
            auth_rmsg = 'Authored: %s' % ', '.join(auth_ret)
        if not edit_ret:
            edit_rmsg = "Edited: None found"
        else:
            edit_rmsg = 'Edited: %s' % ', '.join(edit_ret)
        irc.reply(auth_rmsg)
        irc.reply(edit_rmsg)
    lookup = wrap(lookup, [optional("otherUser"), optional("channel")])

    class ignore(callbacks.Commands):
        def add(self, irc, msg, args, banmask, expires, channel):
            """<hostmask|nick> [<expires>] [<channel>]

            Ignores commands/requests from <hostmask> or <nick>. If <expires> is
            given, the ignore will expire after that ammount of seconds.
            If <channel> is given, the ignore will only apply in that channel.
            """
            if not capab(msg.prefix, "editfactoids"):
                irc.errorNoCapability("editfactoids")
                return
            if channel:
                c = ircdb.channels.getChannel(channel)
                c.addIgnore(banmask, expires)
                ircdb.channels.setChannel(channel, c)
                irc.replySuccess()
            else:
                ircdb.ignores.add(banmask, expires)
                irc.replySuccess()
        add = wrap(add, ['hostmask', optional("expiry", 0), optional("channel")])

        def remove(self, irc, msg, args, banmask, channel):
            """<hostmask|nick> [<channel>]

            Removes an ignore previously set by @ignore. If <channel> was
            given in the original @ignore command, it must be given here.
            """
            if not capab(msg.prefix, "editfactoids"):
                irc.errorNoCapability("editfactoids")
                return
            if channel:
                c = ircdb.channels.getChannel(channel)
                try:
                    c.removeIgnore(banmask)
                    ircdb.channels.setChannel(channel, c)
                    irc.replySuccess()
                except KeyError:
                    irc.error("That hostmask is not ignored in %s" % channel)
            else:
                try:
                    ircdb.ignores.remove(banmask)
                    irc.replySuccess()
                except KeyError:
                    irc.error("That hostmask is not globally ignored")
        remove = wrap(remove, ['hostmask', optional("channel")])

    def ignores(self, irc, msg, args, channel):
        """[<channel>]

        Lists all ignores set by @ignore. If <channel> is given,
        this will only list ignores set in that channel.
        """
        if not capab(msg.prefix, "editfactoids"):
            irc.errorNoCapability("editfactoids")
            return
        if channel:
            c = ircdb.channels.getChannel(channel)
            if not c.ignores:
                irc.reply("I'm not currently ignoring anyone in %s" % channel)
            else:
                L = sorted(c.ignores)
                irc.reply(utils.str.commaAndify(list(map(repr, L))))
        else:
            if ircdb.ignores.hostmasks:
                irc.reply(format('%L', (list(map(repr, ircdb.ignores.hostmasks)))))
            else:
                irc.reply("I'm not currently globally ignoring anyone")
    ignores = wrap(ignores, [optional("channel")])

Class = Encyclopedia