# Copyright 2010 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2

import codecs
import logging
import re

try:
	from configparser import SafeConfigParser, ParsingError
except ImportError:
	from ConfigParser import SafeConfigParser, ParsingError
from portage import os
from portage.const import USER_CONFIG_PATH, GLOBAL_CONFIG_PATH, REPO_NAME_LOC
from portage.env.loaders import KeyValuePairFileLoader
from portage.util import normalize_path, writemsg, writemsg_level, shlex_split
from portage.localization import _
from portage import _unicode_encode
from portage import _encodings

_repo_name_sub_re = re.compile(r'[^\w-]')

def _gen_valid_repo(name):
	"""
	Substitute hyphen in place of characters that don't conform to PMS 3.1.5,
	and strip hyphen from left side if necessary. This returns None if the
	given name contains no valid characters.
	"""
	name = _repo_name_sub_re.sub(' ', name.strip())
	name = '-'.join(name.split())
	name = name.lstrip('-')
	if not name:
		name = None
	return name

class RepoConfig(object):
	"""Stores config of one repository"""

	__slots__ = ['aliases', 'eclass_overrides', 'eclass_locations', 'location', 'user_location', 'masters', 'main_repo',
		'missing_repo_name', 'name', 'priority', 'sync', 'format']

	def __init__(self, name, repo_opts):
		"""Build a RepoConfig with options in repo_opts
		   Try to read repo_name in repository location, but if
		   it is not found use variable name as repository name"""
		aliases = repo_opts.get('aliases')
		if aliases is not None:
			aliases = tuple(aliases.split())
		self.aliases = aliases

		eclass_overrides = repo_opts.get('eclass-overrides')
		if eclass_overrides is not None:
			eclass_overrides = tuple(eclass_overrides.split())
		self.eclass_overrides = eclass_overrides
		#Locations are computed later.
		self.eclass_locations = None

		#Masters are only read from layout.conf.
		self.masters = None

		#The main-repo key makes only sense for the 'DEFAULT' section.
		self.main_repo = repo_opts.get('main-repo')

		priority = repo_opts.get('priority')
		if priority is not None:
			try:
				priority = int(priority)
			except ValueError:
				priority = None
		self.priority = priority

		sync = repo_opts.get('sync')
		if sync is not None:
			sync = sync.strip()
		self.sync = sync

		format = repo_opts.get('format')
		if format is not None:
			format = format.strip()
		self.format = format

		location = repo_opts.get('location')
		self.user_location = location
		if location is not None:
			if os.path.isdir(location):
				location = os.path.realpath(location)
		self.location = location

		missing = True
		if self.location is not None:
			name, missing = self._read_repo_name(self.location)
			# We must ensure that the name conforms to PMS 3.1.5
			# in order to avoid InvalidAtom exceptions when we
			# use it to generate atoms.
			name = _gen_valid_repo(name)
			if not name:
				# name only contains invalid characters
				name = "x-" + os.path.basename(self.location)
				name = _gen_valid_repo(name)
				# If basename only contains whitespace then the
				# end result is name = 'x-'.

		elif name == "DEFAULT": 
			missing = False
		self.name = name
		self.missing_repo_name = missing

	def update(self, new_repo):
		"""Update repository with options in another RepoConfig"""
		if new_repo.aliases is not None:
			self.aliases = new_repo.aliases
		if new_repo.eclass_overrides is not None:
			self.eclass_overrides = new_repo.eclass_overrides
		if new_repo.masters is not None:
			self.masters = new_repo.masters
		if new_repo.name is not None:
			self.name = new_repo.name
		if new_repo.user_location is not None:
			self.user_location = new_repo.user_location
		if new_repo.location is not None:
			self.location = new_repo.location
		if new_repo.priority is not None:
			self.priority = new_repo.priority
		if new_repo.sync is not None:
			self.sync = new_repo.sync

	def _read_repo_name(self, repo_path):
		"""
		Read repo_name from repo_path.
		Returns repo_name, missing.
		"""
		repo_name_path = os.path.join(repo_path, REPO_NAME_LOC)
		try:
			return codecs.open(
				_unicode_encode(repo_name_path,
				encoding=_encodings['fs'], errors='strict'),
				mode='r', encoding=_encodings['repo.content'],
				errors='replace').readline().strip(), False
		except EnvironmentError:
			return "x-" + os.path.basename(repo_path), True

	def info_string(self):
		"""
		Returns a formatted string containing informations about the repository.
		Used by emerge --info.
		"""
		indent = " " * 4
		repo_msg = []
		repo_msg.append(self.name)
		if self.format:
			repo_msg.append(indent + "format: " + self.format)
		if self.user_location:
			repo_msg.append(indent + "location: " + self.user_location)
		if self.sync:
			repo_msg.append(indent + "sync: " + self.sync)
		if self.masters:
			repo_msg.append(indent + "masters: " + " ".join(master.name for master in self.masters))
		if self.priority:
			repo_msg.append(indent + "priority: " + str(self.priority))
		if self.aliases:
			repo_msg.append(indent + "aliases: " + self.aliases)
		if self.eclass_overrides:
			repo_msg.append(indent + "eclass_overrides: " + self.eclass_overrides)
		repo_msg.append("")
		return "\n".join(repo_msg) + "\n"

class RepoConfigLoader(object):
	"""Loads and store config of several repositories, loaded from PORTDIR_OVERLAY or repos.conf"""
	def __init__(self, paths, settings):
		"""Load config from files in paths"""
		def parse(paths, prepos, ignored_map, ignored_location_map):
			"""Parse files in paths to load config"""
			parser = SafeConfigParser()
			try:
				parser.read(paths)
			except ParsingError as e:
				writemsg(_("!!! Error while reading repo config file: %s\n") % e, noiselevel=-1)
			prepos['DEFAULT'] = RepoConfig("DEFAULT", parser.defaults())
			for sname in parser.sections():
				optdict = {}
				for oname in parser.options(sname):
					optdict[oname] = parser.get(sname, oname)

				repo = RepoConfig(sname, optdict)
				if repo.location and not os.path.exists(repo.location):
					writemsg(_("!!! Invalid repos.conf entry '%s'"
						" (not a dir): '%s'\n") % (sname, repo.location), noiselevel=-1)
					continue

				if repo.name in prepos:
					old_location = prepos[repo.name].location
					if old_location is not None and repo.location is not None and old_location != repo.location:
						ignored_map.setdefault(repo.name, []).append(old_location)
						ignored_location_map[old_location] = repo.name
					prepos[repo.name].update(repo)
				else:
					prepos[repo.name] = repo

		def add_overlays(portdir, portdir_overlay, prepos, ignored_map, ignored_location_map):
			"""Add overlays in PORTDIR_OVERLAY as repositories"""
			overlays = []
			if portdir:
				portdir = normalize_path(portdir)
				overlays.append(portdir)
			port_ov = [normalize_path(i) for i in shlex_split(portdir_overlay)]
			overlays.extend(port_ov)
			default_repo_opts = {}
			if prepos['DEFAULT'].aliases is not None:
				default_repo_opts['aliases'] = \
					' '.join(prepos['DEFAULT'].aliases)
			if prepos['DEFAULT'].eclass_overrides is not None:
				default_repo_opts['eclass-overrides'] = \
					' '.join(prepos['DEFAULT'].eclass_overrides)
			if prepos['DEFAULT'].masters is not None:
				default_repo_opts['masters'] = \
					' '.join(prepos['DEFAULT'].masters)
			if overlays:
				#overlay priority is negative because we want them to be looked before any other repo
				base_priority = -1
				for ov in overlays:
					if os.path.isdir(ov):
						repo_opts = default_repo_opts.copy()
						repo_opts['location'] = ov
						repo = RepoConfig(None, repo_opts)
						repo_conf_opts = prepos.get(repo.name)
						if repo_conf_opts is not None:
							if repo_conf_opts.aliases is not None:
								repo_opts['aliases'] = \
									' '.join(repo_conf_opts.aliases)
							if repo_conf_opts.eclass_overrides is not None:
								repo_opts['eclass-overrides'] = \
									' '.join(repo_conf_opts.eclass_overrides)
							if repo_conf_opts.masters is not None:
								repo_opts['masters'] = \
									' '.join(repo_conf_opts.masters)
						repo = RepoConfig(repo.name, repo_opts)
						if repo.name in prepos:
							old_location = prepos[repo.name].location
							if old_location is not None and old_location != repo.location:
								ignored_map.setdefault(repo.name, []).append(old_location)
								ignored_location_map[old_location] = repo.name
							prepos[repo.name].update(repo)
						else:
							if ov == portdir and portdir not in port_ov:
								repo.priority = 1000
							else:
								repo.priority = base_priority
								base_priority -= 1
							prepos[repo.name] = repo
					else:
						writemsg(_("!!! Invalid PORTDIR_OVERLAY"
							" (not a dir): '%s'\n") % ov, noiselevel=-1)
		def repo_priority(r):
			"""
			Key funtion for comparing repositories by priority.
			None is equal priority zero.
			"""
			x = prepos[r].priority
			if x is None:
				return 0
			return x

		prepos = {}
		location_map = {}
		treemap = {}
		ignored_map = {}
		ignored_location_map = {}

		portdir = os.path.realpath(settings.get('PORTDIR', ''))
		portdir_overlay = settings.get('PORTDIR_OVERLAY', '')
		parse(paths, prepos, ignored_map, ignored_location_map)
		add_overlays(portdir, portdir_overlay, prepos, ignored_map, ignored_location_map)
		ignored_repos = tuple((repo_name, tuple(paths)) \
			for repo_name, paths in ignored_map.items())

		self.missing_repo_names = frozenset(repo.location for repo in prepos.values() if repo.missing_repo_name)

		#Parse layout.conf and read masters key.
		for repo in prepos.values():
			if not repo.location:
				continue
			layout_filename = os.path.join(repo.location, "metadata", "layout.conf")
			layout_file = KeyValuePairFileLoader(layout_filename, None, None)
			layout_data, layout_errors = layout_file.load()

			masters = layout_data.get('masters')
			if masters and masters.strip():
				masters = masters.split()
			else:
				masters = None
			repo.masters = masters

		#Take aliases into account.
		new_prepos = {}
		for repo_name, repo in prepos.items():
			names = set()
			names.add(repo_name)
			if repo.aliases:
				names.update(repo.aliases)

			for name in names:
				if name in new_prepos:
					writemsg_level(_("!!! Repository name or alias '%s', " + \
						"defined for repository '%s', overrides " + \
						"existing alias or repository.\n") % (name, repo_name), level=logging.WARNING, noiselevel=-1)
				new_prepos[name] = repo
		prepos = new_prepos

		for (name, r) in prepos.items():
			if r.location is not None:
				location_map[r.location] = name
				treemap[name] = r.location

		prepos_order = [repo.name for repo in prepos.values() if repo.location is not None]
		prepos_order.sort(key=repo_priority, reverse=True)

		if portdir in location_map:
			portdir_repo = prepos[location_map[portdir]]
			portdir_sync = settings.get('SYNC', '')
			#if SYNC variable is set and not overwritten by repos.conf
			if portdir_sync and not portdir_repo.sync:
				portdir_repo.sync = portdir_sync

		if prepos['DEFAULT'].main_repo is None or \
			prepos['DEFAULT'].main_repo not in prepos:
			#setting main_repo if it was not set in repos.conf
			if portdir in location_map:
				prepos['DEFAULT'].main_repo = location_map[portdir]
			elif portdir in ignored_location_map:
				prepos['DEFAULT'].main_repo = ignored_location_map[portdir]
			else:
				prepos['DEFAULT'].main_repo = None
				writemsg(_("!!! main-repo not set in DEFAULT and PORTDIR is empty. \n"), noiselevel=-1)

		self.prepos = prepos
		self.prepos_order = prepos_order
		self.ignored_repos = ignored_repos
		self.location_map = location_map
		self.treemap = treemap
		self._prepos_changed = True
		self._repo_location_list = []

		#The 'masters' key currently contains repo names. Replace them with the matching RepoConfig.
		for repo_name, repo in prepos.items():
			if repo_name == "DEFAULT":
				continue
			if repo.masters is None:
				if self.mainRepo() and repo_name != self.mainRepo().name:
					repo.masters = self.mainRepo(),
				else:
					repo.masters = ()
			else:
				if repo.masters and isinstance(repo.masters[0], RepoConfig):
					# This one has already been processed
					# because it has an alias.
					continue
				master_repos = []
				for master_name in repo.masters:
					if master_name not in prepos:
						writemsg_level(_("Unavailable repository '%s' " \
							"referenced by masters entry in '%s'\n") % \
							(master_name, layout_filename),
							level=logging.ERROR, noiselevel=-1)
					else:
						master_repos.append(prepos[master_name])
				repo.masters = tuple(master_repos)

		#The 'eclass_overrides' key currently contains repo names. Replace them with the matching repo paths.
		for repo_name, repo in prepos.items():
			if repo_name == "DEFAULT":
				continue

			eclass_locations = []
			eclass_locations.extend(master_repo.location for master_repo in repo.masters)
			eclass_locations.append(repo.location)

			if repo.eclass_overrides:
				for other_repo_name in repo.eclass_overrides:
					if other_repo_name in self.treemap:
						eclass_locations.append(self.get_location_for_name(other_repo_name))
					else:
						writemsg_level(_("Unavailable repository '%s' " \
							"referenced by eclass-overrides entry for " \
							"'%s'\n") % (other_repo_name, repo_name), \
							level=logging.ERROR, noiselevel=-1)
			repo.eclass_locations = tuple(eclass_locations)

		self._prepos_changed = True
		self._repo_location_list = []

		self._check_locations()

	def repoLocationList(self):
		"""Get a list of repositories location. Replaces PORTDIR_OVERLAY"""
		if self._prepos_changed:
			_repo_location_list = []
			for repo in self.prepos_order:
				if self.prepos[repo].location is not None:
					_repo_location_list.append(self.prepos[repo].location)
			self._repo_location_list = tuple(_repo_location_list)

			self._prepos_changed = False
		return self._repo_location_list

	def repoUserLocationList(self):
		"""Get a list of repositories location. Replaces PORTDIR_OVERLAY"""
		user_location_list = []
		for repo in self.prepos_order:
			if self.prepos[repo].location is not None:
				user_location_list.append(self.prepos[repo].user_location)
		return tuple(user_location_list)

	def mainRepoLocation(self):
		"""Returns the location of main repo"""
		main_repo = self.prepos['DEFAULT'].main_repo
		if main_repo is not None and main_repo in self.prepos:
			return self.prepos[main_repo].location
		else:
			return ''

	def mainRepo(self):
		"""Returns the main repo"""
		maid_repo = self.prepos['DEFAULT'].main_repo
		if maid_repo is None:
			return None
		return self.prepos[maid_repo]

	def _check_locations(self):
		"""Check if repositories location are correct and show a warning message if not"""
		for (name, r) in self.prepos.items():
			if name != 'DEFAULT':
				if r.location is None:
					writemsg(_("!!! Location not set for repository %s\n") % name, noiselevel=-1)
				else:
					if not os.path.isdir(r.location):
						self.prepos_order.remove(name)
						writemsg(_("!!! Invalid Repository Location"
							" (not a dir): '%s'\n") % r.location, noiselevel=-1)

	def repos_with_profiles(self):
		for repo_name in self.prepos_order:
			repo = self.prepos[repo_name]
			if repo.format != "unavailable":
				yield repo

	def get_name_for_location(self, location):
		return self.location_map[location]

	def get_location_for_name(self, repo_name):
		if repo_name is None:
			# This simplifies code in places where
			# we want to be able to pass in Atom.repo
			# even if it is None.
			return None
		return self.treemap[repo_name]

	def __iter__(self):
		for repo_name in self.prepos_order:
			yield self.prepos[repo_name]

def load_repository_config(settings):
	#~ repoconfigpaths = [os.path.join(settings.global_config_path, "repos.conf")]
	repoconfigpaths = []
	if settings.local_config:
		repoconfigpaths.append(os.path.join(settings["PORTAGE_CONFIGROOT"],
			USER_CONFIG_PATH, "repos.conf"))
	return RepoConfigLoader(repoconfigpaths, settings)