# Copyright (C) 2012 Yahoo! Inc.

#

# Author: Joshua Harlow <harlowja@yahoo-inc.com>

#

# This file is part of cloud-init. See LICENSE file for license information.

from six import StringIO

from cloudinit.distros.parsers import chop_comment

# See: man hosts

# or https://linux.die.net/man/5/hosts

# or https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/configtuning-configfiles.html # noqa

class HostsConf(object):

    def __init__(self, text):

        self._text = text

        self._contents = None

    def parse(self):

        if self._contents is None:

            self._contents = self._parse(self._text)

    def get_entry(self, ip):

        self.parse()

        options = []

        for (line_type, components) in self._contents:

            if line_type == 'option':

                (pieces, _tail) = components

                if len(pieces) and pieces[0] == ip:

                    options.append(pieces[1:])

        return options

    def del_entries(self, ip):

        self.parse()

        n_entries = []

        for (line_type, components) in self._contents:

            if line_type != 'option':

                n_entries.append((line_type, components))

                continue

            else:

                (pieces, _tail) = components

                if len(pieces) and pieces[0] == ip:

                    pass

                elif len(pieces):

                    n_entries.append((line_type, list(components)))

        self._contents = n_entries

    def add_entry(self, ip, canonical_hostname, *aliases):

        self.parse()

        self._contents.append(('option',

                              ([ip, canonical_hostname] + list(aliases), '')))

    def _parse(self, contents):

        entries = []

        for line in contents.splitlines():

            if not len(line.strip()):

                entries.append(('blank', [line]))

                continue

            (head, tail) = chop_comment(line.strip(), '#')

            if not len(head):

                entries.append(('all_comment', [line]))

                continue

            entries.append(('option', [head.split(None), tail]))

        return entries

    def __str__(self):

        self.parse()

        contents = StringIO()

        for (line_type, components) in self._contents:

            if line_type == 'blank':

                contents.write("%s\n" % (components[0]))

            elif line_type == 'all_comment':

                contents.write("%s\n" % (components[0]))

            elif line_type == 'option':

                (pieces, tail) = components

                pieces = [str(p) for p in pieces]

                pieces = "\t".join(pieces)

                contents.write("%s%s\n" % (pieces, tail))

        return contents.getvalue()

# vi: ts=4 expandtab