# -*- coding: utf-8 -*-
#
# Copyright (C) 2013-2014 Maarten de Vries <maarten@de-vri.es>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# 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.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

#
# Autosort automatically keeps your buffers sorted and grouped by server.
# You can define your own sorting rules. See /help autosort for more details.
#
# http://github.com/de-vri.es/weechat-autosort
#

#
# Changelog:
# 2.7:
#   * Fix sorting of buffers with spaces in their name.
# 2.6:
#   * Ignore case in rules when doing case insensitive sorting.
# 2.5:
#   * Fix handling unicode buffer names.
#   * Add hint to set irc.look.server_buffer to independent and buffers.look.indenting to on.
# 2.4:
#   * Make script python3 compatible.
# 2.3:
#   * Fix sorting items without score last (regressed in 2.2).
# 2.2:
#   * Add configuration option for signals that trigger a sort.
#   * Add command to manually trigger a sort (/autosort sort).
#   * Add replacement patterns to apply before sorting.
# 2.1:
#   * Fix some minor style issues.
# 2.0:
#   * Allow for custom sort rules.
#


import weechat
import re
import json

SCRIPT_NAME     = 'autosort'
SCRIPT_AUTHOR   = 'Maarten de Vries <maarten@de-vri.es>'
SCRIPT_VERSION  = '2.7'
SCRIPT_LICENSE  = 'GPL3'
SCRIPT_DESC     = 'Automatically or manually keep your buffers sorted and grouped by server.'


config = None
hooks  = []

class HumanReadableError(Exception):
	pass


def parse_int(arg, arg_name = 'argument'):
	''' Parse an integer and provide a more human readable error. '''
	arg = arg.strip()
	try:
		return int(arg)
	except ValueError:
		raise HumanReadableError('Invalid {0}: expected integer, got "{1}".'.format(arg_name, arg))


class Pattern:
	''' A simple glob-like pattern for matching buffer names. '''

	def __init__(self, pattern, case_sensitive):
		''' Construct a pattern from a string. '''
		escaped    = False
		char_class = 0
		chars      = ''
		regex      = ''
		for c in pattern:
			if escaped and char_class:
				escaped = False
				chars += re.escape(c)
			elif escaped:
				escaped = False
				regex += re.escape(c)
			elif c == '\\':
				escaped = True
			elif c == '*' and not char_class:
				regex += '[^.]*'
			elif c == '?' and not char_class:
				regex += '[^.]'
			elif c == '[' and not char_class:
				char_class = 1
				chars    = ''
			elif c == '^' and char_class and not chars:
				chars += '^'
			elif c == ']' and char_class and chars not in ('', '^'):
				char_class = False
				regex += '[' + chars + ']'
			elif c == '-' and char_class:
				chars += '-'
			elif char_class:
				chars += re.escape(c)
			else:
				regex += re.escape(c)

		if char_class:
			raise ValueError("unmatched opening '['")
		if escaped:
			raise ValueError("unexpected trailing '\\'")

		if case_sensitive:
			self.regex   = re.compile('^' + regex + '$')
		else:
			self.regex   = re.compile('^' + regex + '$', flags = re.IGNORECASE)
		self.pattern = pattern

	def match(self, input):
		''' Match the pattern against a string. '''
		return self.regex.match(input)


class FriendlyList(object):
	''' A list with human readable errors. '''

	def __init__(self):
		self.__data = []

	def raw(self):
		return self.__data

	def append(self, value):
		''' Add a rule to the list. '''
		self.__data.append(value)

	def insert(self, index, value):
		''' Add a rule to the list. '''
		if not 0 <= index <= len(self): raise HumanReadableError('Index out of range: expected an integer in the range [0, {0}], got {1}.'.format(len(self), index))
		self.__data.insert(index, value)

	def pop(self, index):
		''' Remove a rule from the list and return it. '''
		if not 0 <= index < len(self): raise HumanReadableError('Index out of range: expected an integer in the range [0, {0}), got {1}.'.format(len(self), index))
		return self.__data.pop(index)

	def move(self, index_a, index_b):
		''' Move a rule to a new position in the list. '''
		self.insert(index_b, self.pop(index_a))

	def swap(self, index_a, index_b):
		''' Swap two elements in the list. '''
		self[index_a], self[index_b] = self[index_b], self[index_a]

	def __len__(self):
		return len(self.__data)

	def __getitem__(self, index):
		if not 0 <= index < len(self): raise HumanReadableError('Index out of range: expected an integer in the range [0, {0}), got {1}.'.format(len(self), index))
		return self.__data[index]

	def __setitem__(self, index, value):
		if not 0 <= index < len(self): raise HumanReadableError('Index out of range: expected an integer in the range [0, {0}), got {1}.'.format(len(self), index))
		self.__data[index] = value

	def __iter__(self):
		return iter(self.__data)


class RuleList(FriendlyList):
	''' A list of rules to test buffer names against. '''
	rule_regex = re.compile(r'^(.*)=\s*([+-]?[^=]*)$')

	def __init__(self, rules):
		''' Construct a RuleList from a list of rules. '''
		super(RuleList, self).__init__()
		for rule in rules: self.append(rule)

	def get_score(self, name):
		''' Get the sort score of a partial name according to a rule list. '''
		for rule in self:
			if rule[0].match(name): return rule[1]
		return 999999999

	def encode(self):
		''' Encode the rules for storage. '''
		return json.dumps(list(map(lambda x: (x[0].pattern, x[1]), self)))

	@staticmethod
	def decode(blob, case_sensitive):
		''' Parse rules from a string blob. '''
		result = []

		try:
			decoded = json.loads(blob)
		except ValueError:
			log('Invalid rules: expected JSON encoded list of pairs, got "{0}".'.format(blob))
			return [], 0

		for rule in decoded:
			# Rules must be a pattern,score pair.
			if len(rule) != 2:
				log('Invalid rule: expected (pattern, score), got "{0}". Rule ignored.'.format(rule))
				continue

			# Rules must have a valid pattern.
			try:
				pattern = Pattern(rule[0], case_sensitive)
			except ValueError as e:
				log('Invalid pattern: {0} in "{1}". Rule ignored.'.format(e, rule[0]))
				continue

			# Rules must have a valid score.
			try:
				score = int(rule[1])
			except ValueError as e:
				log('Invalid score: expected an integer, got "{0}". Rule ignored.'.format(score))
				continue

			result.append((pattern, score))

		return RuleList(result)

	@staticmethod
	def parse_rule(arg, case_sensitive):
		''' Parse a rule argument. '''
		arg = arg.strip()
		match = RuleList.rule_regex.match(arg)
		if not match:
			raise HumanReadableError('Invalid rule: expected "<pattern> = <score>", got "{0}".'.format(arg))

		pattern = match.group(1).strip()
		try:
			pattern = Pattern(pattern, case_sensitive)
		except ValueError as e:
			raise HumanReadableError('Invalid pattern: {0} in "{1}".'.format(e, pattern))

		score   = parse_int(match.group(2), 'score')
		return (pattern, score)


def decode_replacements(blob):
	''' Decode a replacement list encoded as JSON. '''
	result = FriendlyList()
	try:
		decoded = json.loads(blob)
	except ValueError:
		log('Invalid replacement list: expected JSON encoded list of pairs, got "{0}".'.format(blob))
		return [], 0

	for replacement in decoded:
		# Replacements must be a (string, string) pair.
		if len(replacement) != 2:
			log('Invalid replacement pattern: expected (pattern, replacement), got "{0}". Replacement ignored.'.format(rule))
			continue
		result.append(replacement)

	return result


def encode_replacements(replacements):
	''' Encode a list of replacement patterns as JSON. '''
	return json.dumps(replacements.raw())


class Config:
	''' The autosort configuration. '''

	default_rules = json.dumps([
		('core', 0),
		('irc',  2),
		('*',    1),

		('irc.irc_raw', 0),
		('irc.server',  1),
	])

	default_replacements = '[]'
	default_signals      = 'buffer_opened buffer_merged buffer_unmerged buffer_renamed'

	def __init__(self, filename):
		''' Initialize the configuration. '''

		self.filename         = filename
		self.config_file      = weechat.config_new(self.filename, '', '')
		self.sorting_section  = None

		self.case_sensitive   = False
		self.group_irc        = True
		self.rules            = []
		self.replacements     = []
		self.signals          = []
		self.sort_on_config   = True

		self.__case_sensitive = None
		self.__group_irc      = None
		self.__rules          = None
		self.__replacements   = None
		self.__signals        = None
		self.__sort_on_config = None

		if not self.config_file:
			log('Failed to initialize configuration file "{0}".'.format(self.filename))
			return

		self.sorting_section = weechat.config_new_section(self.config_file, 'sorting', False, False, '', '', '', '', '', '', '', '', '', '')

		if not self.sorting_section:
			log('Failed to initialize section "sorting" of configuration file.')
			weechat.config_free(self.config_file)
			return

		self.__case_sensitive = weechat.config_new_option(
			self.config_file, self.sorting_section,
			'case_sensitive', 'boolean',
			'If this option is on, sorting is case sensitive.',
			'', 0, 0, 'off', 'off', 0,
			'', '', '', '', '', ''
		)

		self.__group_irc = weechat.config_new_option(
			self.config_file, self.sorting_section,
			'group_irc', 'boolean',
			'If this option is on, the script pretends that IRC channel/private buffers are renamed to "irc.server.{network}.{channel}" rather than "irc.{network}.{channel}".' +
			'This ensures that these buffers are grouped with their respective server buffer.',
			'', 0, 0, 'on', 'on', 0,
			'', '', '', '', '', ''
		)

		self.__rules = weechat.config_new_option(
			self.config_file, self.sorting_section,
			'rules', 'string',
			'An ordered list of sorting rules encoded as JSON. See /help autosort for commands to manipulate these rules.',
			'', 0, 0, Config.default_rules, Config.default_rules, 0,
			'', '', '', '', '', ''
		)

		self.__replacements = weechat.config_new_option(
			self.config_file, self.sorting_section,
			'replacements', 'string',
			'An ordered list of replacement patterns to use on buffer name components, encoded as JSON. See /help autosort for commands to manipulate these replacements.',
			'', 0, 0, Config.default_replacements, Config.default_replacements, 0,
			'', '', '', '', '', ''
		)

		self.__signals = weechat.config_new_option(
			self.config_file, self.sorting_section,
			'signals', 'string',
			'The signals that will cause autosort to resort your buffer list. Seperate signals with spaces.',
			'', 0, 0, Config.default_signals, Config.default_signals, 0,
			'', '', '', '', '', ''
		)

		self.__sort_on_config = weechat.config_new_option(
			self.config_file, self.sorting_section,
			'sort_on_config_change', 'boolean',
			'Decides if the buffer list should be sorted when autosort configuration changes.',
			'', 0, 0, 'on', 'on', 0,
			'', '', '', '', '', ''
		)

		if weechat.config_read(self.config_file) != weechat.WEECHAT_RC_OK:
			log('Failed to load configuration file.')

		if weechat.config_write(self.config_file) != weechat.WEECHAT_RC_OK:
			log('Failed to write configuration file.')

		self.reload()

	def reload(self):
		''' Load configuration variables. '''

		self.case_sensitive = weechat.config_boolean(self.__case_sensitive)
		self.group_irc      = weechat.config_boolean(self.__group_irc)

		rules_blob          = weechat.config_string(self.__rules)
		replacements_blob   = weechat.config_string(self.__replacements)
		signals_blob        = weechat.config_string(self.__signals)

		self.rules          = RuleList.decode(rules_blob, self.case_sensitive)
		self.replacements   = decode_replacements(replacements_blob)
		self.signals        = signals_blob.split()
		self.sort_on_config = weechat.config_boolean(self.__sort_on_config)

	def save_rules(self, run_callback = True):
		''' Save the current rules to the configuration. '''
		weechat.config_option_set(self.__rules, RuleList.encode(self.rules), run_callback)

	def save_replacements(self, run_callback = True):
		''' Save the current replacement patterns to the configuration. '''
		weechat.config_option_set(self.__replacements, encode_replacements(self.replacements), run_callback)


def pad(sequence, length, padding = None):
	''' Pad a list until is has a certain length. '''
	return sequence + [padding] * max(0, (length - len(sequence)))


def log(message, buffer = 'NULL'):
	weechat.prnt(buffer, 'autosort: {0}'.format(message))


def get_buffers():
	''' Get a list of all the buffers in weechat. '''
	buffers = []

	buffer_list = weechat.infolist_get('buffer', '', '')

	while weechat.infolist_next(buffer_list):
		name   = weechat.infolist_string (buffer_list, 'full_name')
		number = weechat.infolist_integer(buffer_list, 'number')

		# Buffer is merged with one we already have in the list, skip it.
		if number <= len(buffers):
			continue
		buffers.append((name, number - 1))

	weechat.infolist_free(buffer_list)
	return buffers


def preprocess(buffer, config):
	'''
	Preprocess a buffers names.
	'''
	if not config.case_sensitive:
		buffer = buffer.lower()

	for replacement in config.replacements:
		buffer = buffer.replace(replacement[0], replacement[1])

	buffer = buffer.split('.')
	if config.group_irc and len(buffer) >= 2 and buffer[0] == 'irc' and buffer[1] not in ('server', 'irc_raw'):
		buffer.insert(1, 'server')

	return buffer


def buffer_sort_key(rules):
	''' Create a sort key function for a buffer list from a rule list. '''
	def key(buffer):
		result  = []
		name    = ''
		for word in preprocess(buffer[0].decode('utf-8'), config):
			name += ('.' if name else '') + word
			result.append((rules.get_score(name), word))
		return result

	return key


def apply_buffer_order(order):
	''' Sort the buffers in weechat according to the given order. '''
	indices = list(order)
	reverse = [0] * len(indices)
	for i, index in enumerate(indices):
		reverse[index] = i

	for i in range(len(indices)):
		wanted = indices[i]
		if wanted == i: continue
		# Weechat buffers are 1-indexed, but our indices aren't.
		weechat.command('', '/buffer swap {0} {1}'.format(i + 1, wanted + 1))
		indices[reverse[i]] = wanted
		reverse[wanted]     = reverse[i]


def split_args(args, expected, optional = 0):
	''' Split an argument string in the desired number of arguments. '''
	split = args.split(' ', expected - 1)
	if (len(split) < expected):
		raise HumanReadableError('Expected at least {0} arguments, got {1}.'.format(expected, len(split)))
	return split[:-1] + pad(split[-1].split(' ', optional), optional + 1, '')


def command_sort(buffer, command, args):
	''' Sort the buffers and print a confirmation. '''
	on_buffers_changed()
	log("Finished sorting buffers.", buffer)
	return weechat.WEECHAT_RC_OK


def command_rule_list(buffer, command, args):
	''' Show the list of sorting rules. '''
	output = 'Sorting rules:\n'
	for i, rule in enumerate(config.rules):
		output += '    {0}: {1} = {2}\n'.format(i, rule[0].pattern, rule[1])
	if not len(config.rules):
		output += '    No sorting rules configured.\n'
	log(output, buffer)

	return weechat.WEECHAT_RC_OK


def command_rule_add(buffer, command, args):
	''' Add a rule to the rule list. '''
	rule = RuleList.parse_rule(args, config.case_sensitive)

	config.rules.append(rule)
	config.save_rules()
	command_rule_list(buffer, command, '')

	return weechat.WEECHAT_RC_OK


def command_rule_insert(buffer, command, args):
	''' Insert a rule at the desired position in the rule list. '''
	index, rule = split_args(args, 2)
	index = parse_int(index, 'index')
	rule  = RuleList.parse_rule(rule, config.case_sensitive)

	config.rules.insert(index, rule)
	config.save_rules()
	command_rule_list(buffer, command, '')
	return weechat.WEECHAT_RC_OK


def command_rule_update(buffer, command, args):
	''' Update a rule in the rule list. '''
	index, rule = split_args(args, 2)
	index = parse_int(index, 'index')
	rule  = RuleList.parse_rule(rule, config.case_sensitive)

	config.rules[index] = rule
	config.save_rules()
	command_rule_list(buffer, command, '')
	return weechat.WEECHAT_RC_OK


def command_rule_delete(buffer, command, args):
	''' Delete a rule from the rule list. '''
	index = args.strip()
	index = parse_int(index, 'index')

	config.rules.pop(index)
	config.save_rules()
	command_rule_list(buffer, command, '')
	return weechat.WEECHAT_RC_OK


def command_rule_move(buffer, command, args):
	''' Move a rule to a new position. '''
	index_a, index_b = split_args(args, 2)
	index_a = parse_int(index_a, 'index')
	index_b = parse_int(index_b, 'index')

	config.rules.move(index_a, index_b)
	config.save_rules()
	command_rule_list(buffer, command, '')
	return weechat.WEECHAT_RC_OK


def command_rule_swap(buffer, command, args):
	''' Swap two rules. '''
	index_a, index_b = split_args(args, 2)
	index_a = parse_int(index_a, 'index')
	index_b = parse_int(index_b, 'index')

	config.rules.swap(index_a, index_b)
	config.save_rules()
	command_rule_list(buffer, command, '')
	return weechat.WEECHAT_RC_OK


def command_replacement_list(buffer, command, args):
	''' Show the list of sorting rules. '''
	output = 'Replacement patterns:\n'
	for i, pattern in enumerate(config.replacements):
		output += '    {0}: {1} -> {2}\n'.format(i, pattern[0], pattern[1])
	if not len(config.replacements):
		output += '    No replacement patterns configured.'
	log(output, buffer)

	return weechat.WEECHAT_RC_OK


def command_replacement_add(buffer, command, args):
	''' Add a rule to the rule list. '''
	pattern, replacement = split_args(args, 1, 1)

	config.replacements.append((pattern, replacement))
	config.save_replacements()
	command_replacement_list(buffer, command, '')

	return weechat.WEECHAT_RC_OK


def command_replacement_insert(buffer, command, args):
	''' Insert a rule at the desired position in the rule list. '''
	index, pattern, replacement = split_args(args, 2, 1)
	index = parse_int(index, 'index')

	config.replacements.insert(index, (pattern, replacement))
	config.save_replacements()
	command_replacement_list(buffer, command, '')
	return weechat.WEECHAT_RC_OK


def command_replacement_update(buffer, command, args):
	''' Update a rule in the rule list. '''
	index, pattern, replacement = split_args(args, 2, 1)
	index = parse_int(index, 'index')

	config.replacements[index] = (pattern, replacement)
	config.save_replacements()
	command_replacement_list(buffer, command, '')
	return weechat.WEECHAT_RC_OK


def command_replacement_delete(buffer, command, args):
	''' Delete a rule from the rule list. '''
	index = args.strip()
	index = parse_int(index, 'index')

	config.replacements.pop(index)
	config.save_replacements()
	command_replacement_list(buffer, command, '')
	return weechat.WEECHAT_RC_OK


def command_replacement_move(buffer, command, args):
	''' Move a rule to a new position. '''
	index_a, index_b = split_args(args, 2)
	index_a = parse_int(index_a, 'index')
	index_b = parse_int(index_b, 'index')

	config.replacements.move(index_a, index_b)
	config.save_replacements()
	command_replacement_list(buffer, command, '')
	return weechat.WEECHAT_RC_OK


def command_replacement_swap(buffer, command, args):
	''' Swap two rules. '''
	index_a, index_b = split_args(args, 2)
	index_a = parse_int(index_a, 'index')
	index_b = parse_int(index_b, 'index')

	config.replacements.swap(index_a, index_b)
	config.save_replacements()
	command_replacement_list(buffer, command, '')
	return weechat.WEECHAT_RC_OK




def call_command(buffer, command, args, subcommands):
	''' Call a subccommand from a dictionary. '''
	subcommand, tail = pad(args.split(' ', 1), 2, '')
	subcommand = subcommand.strip()
	if (subcommand == ''):
		child   = subcommands.get(' ')
	else:
		command = command + [subcommand]
		child   = subcommands.get(subcommand)

	if isinstance(child, dict):
		return call_command(buffer, command, tail, child)
	elif callable(child):
		return child(buffer, command, tail)

	log('{0}: command not found'.format(' '.join(command)))
	return weechat.WEECHAT_RC_ERROR


def on_buffers_changed(*args, **kwargs):
	''' Called whenever the buffer list changes. '''
	buffers = get_buffers()
	buffers.sort(key=buffer_sort_key(config.rules))
	apply_buffer_order([i for _, i in buffers])
	return weechat.WEECHAT_RC_OK


def on_config_changed(*args, **kwargs):
	''' Called whenever the configuration changes. '''
	config.reload()

	# Unhook all signals and hook the new ones.
	for hook in hooks:
		weechat.unhook(hook)
	for signal in config.signals:
		hooks.append(weechat.hook_signal(signal, 'on_buffers_changed', ''))

	if config.sort_on_config:
		on_buffers_changed()

	return weechat.WEECHAT_RC_OK


def on_autosort_command(data, buffer, args):
	''' Called when the autosort command is invoked. '''
	try:
		return call_command(buffer, ['/autosort'], args, {
			' ':      command_sort,
			'sort':   command_sort,

			'rules': {
				' ':         command_rule_list,
				'list':      command_rule_list,
				'add':       command_rule_add,
				'insert':    command_rule_insert,
				'update':    command_rule_update,
				'delete':    command_rule_delete,
				'move':      command_rule_move,
				'swap':      command_rule_swap,
			},
			'replacements': {
				' ':      command_replacement_list,
				'list':   command_replacement_list,
				'add':    command_replacement_add,
				'insert': command_replacement_insert,
				'update': command_replacement_update,
				'delete': command_replacement_delete,
				'move':   command_replacement_move,
				'swap':   command_replacement_swap,
			},
			'sort':   on_buffers_changed,
		})
	except HumanReadableError as e:
		log(e, buffer)
		return weechat.WEECHAT_RC_ERROR


command_description = r'''
NOTE: For the best effect, you may want to consider setting the option irc.look.server_buffer to independent and buffers.look.indenting to on.

# Commands

## Miscellaneous
/autosort sort
Manually trigger the buffer sorting.


## Sorting rules

/autosort rules list
Print the list of sort rules.

/autosort rules add <pattern> = <score>
Add a new rule at the end of the list.

/autosort rules insert <index> <pattern> = <score>
Insert a new rule at the given index in the list.

/autosort rules update <index> <pattern> = <score>
Update a rule in the list with a new pattern and score.

/autosort rules delete <index>
Delete a rule from the list.

/autosort rules move <index_from> <index_to>
Move a rule from one position in the list to another.

/autosort rules swap <index_a> <index_b>
Swap two rules in the list


## Replacement patterns

/autosort replacements list
Print the list of replacement patterns.

/autosort replacements add <pattern> <replacement>
Add a new replacement pattern at the end of the list.

/autosort replacements insert <index> <pattern> <replacement>
Insert a new replacement pattern at the given index in the list.

/autosort replacements update <index> <pattern> <replacement>
Update a replacement pattern in the list.

/autosort replacements delete <index>
Delete a replacement pattern from the list.

/autosort replacements move <index_from> <index_to>
Move a replacement pattern from one position in the list to another.

/autosort replacements swap <index_a> <index_b>
Swap two replacement pattern in the list


# Introduction
Autosort is a weechat script to automatically keep your buffers sorted.
The sort order can be customized by defining your own sort rules,
but the default should be sane enough for most people.
It can also group IRC channel/private buffers under their server buffer if you like.

Autosort first turns buffer names into a list of their components by splitting on them on the period character.
For example, the buffer name "irc.server.freenode" is turned into ['irc', 'server', 'freenode'].
The list of buffers is then lexicographically sorted.

To facilitate custom sort orders, it is possible to assign a score to each component individually before the sorting is done.
Any name component that did not get a score assigned will be sorted after those that did receive a score.
Components are always sorted on their score first and on their name second.
Lower scores are sorted first.

## Automatic or manual sorting
By default, autosort will automatically sort your buffer list whenever a buffer is opened, merged, unmerged or renamed.
This should keep your buffers sorted in almost all situations.
However, you may wish to change the list of signals that cause your buffer list to be sorted.
Simply edit the "autosort.sorting.signals" option to add or remove any signal you like.
If you remove all signals you can still sort your buffers manually with the "/autosort sort" command.
To prevent all automatic sorting, "autosort.sorting.sort_on_config_change" should also be set to off.

## Grouping IRC buffers
In weechat, IRC channel/private buffers are named "irc.<network>.<#channel>",
and IRC server buffers are named "irc.server.<network>".
This does not work very well with lexicographical sorting if you want all buffers for one network grouped together.
That is why autosort comes with the "autosort.sorting.group_irc" option,
which secretly pretends IRC channel/private buffers are called "irc.server.<network>.<#channel>".
The buffers are not actually renamed, autosort simply pretends they are for sorting purposes.

## Replacement patterns
Sometimes you may want to ignore some characters for sorting purposes.
On Freenode for example, you may wish to ignore the difference between channels starting with a double or a single hash sign.
To do so, simply add a replacement pattern that replaces ## with # with the following command:
/autosort replacements add ## #

Replacement patterns do not support wildcards or special characters at the moment.

## Sort rules
You can assign scores to name components by defining sort rules.
The first rule that matches a component decides the score.
Further rules are not examined.
Sort rules use the following syntax:
<glob-pattern> = <score>

You can use the "/autosort rules" command to show and manipulate the list of sort rules.


Allowed special characters in the glob patterns are:

Pattern | Meaning
--------|--------
*       | Matches a sequence of any characters except for periods.
?       | Matches a single character, but not a period.
[a-z]   | Matches a single character in the given regex-like character class.
[^ab]   | A negated regex-like character class.
\*      | A backslash escapes the next characters and removes its special meaning.
\\      | A literal backslash.


## Example
As an example, consider the following rule list:
0: core            = 0
1: irc             = 2
2: *               = 1

3: irc.server.*.#* = 1
4: irc.server.*.*  = 0

Rule 0 ensures the core buffer is always sorted first.
Rule 1 sorts IRC buffers last and rule 2 puts all remaining buffers in between the two.

Rule 3 and 4 would make no sense with the group_irc option off.
With the option on though, these rules will sort private buffers before regular channel buffers.
Rule 3 matches channel buffers and assigns them a higher score,
while rule 4 matches the buffers that remain and assigns them a lower score.
The same effect could also be achieved with a single rule:
irc.server.*.[^#]* = 0
'''

command_completion = 'sort||rules list|add|insert|update|delete|move|swap||replacements list|add|insert|update|delete|move|swap'


if weechat.register(SCRIPT_NAME, SCRIPT_AUTHOR, SCRIPT_VERSION, SCRIPT_LICENSE, SCRIPT_DESC, "", ""):
	config = Config('autosort')

	weechat.hook_config('autosort.*',      'on_config_changed',  '')
	weechat.hook_command('autosort', command_description, '', '', command_completion, 'on_autosort_command', 'NULL')
	on_config_changed()