# -*- coding: utf-8 -*-

import os

from postman import config
from postman.models import Member, MailingList
from postman.storage import JsonStorage as Storage


class Postman():

    def __init__(self, configfile=None):
        if not configfile:
            # FIXME: This is not used right now, we are getting the stuff
            # from postman.config, but we will move configurations to a
            # external ini-style config file soon
            configfile = os.path.join(os.path.dirname(__file__),
                                      '../conf/postman.conf')
        self.configfile = configfile

        # lists were the currently managed mailing lists information is going
        # to be saved
        self.mailings = {}
        self.mailings_addresses = []
        
        # the files were internal information (like active mailing lists,
        # members, etc) is saved
        self.dbs = {'mailings': Storage(os.path.join(config.storage_path,
                                                     'mailings.json')),
                    'members': Storage(os.path.join(config.storage_path,
                                                    'members.json'))}

    def save(self):
        """
        Save all the current managed data to disk
        """
        if self.mailings:
            # Save the config file from where we can reload information about the
            # mailing lists managed by this postman instance
            self.dbs['mailings'].write(self.mailings_addresses)
            # Save each mailing list data into its separated persistence file
            for m in self.mailings.keys():            
                self.mailings[m].save()

    def load(self):
        """
        Load all data from the storage files
        """
        if self.dbs['mailings'].exists():
            # load the list of managed mailing lists
            # FIXME: This is quite naive, we do not perform any check here after
            # loading the data from the json file, which can be modified by
            # untrustred users.
            self.mailings_addresses = self.dbs['mailings'].read()

            # now load all the mailing objects:
            for address in self.mailings_addresses:
                mailing = MailingList(address, address)
                mailing.load()
                self.mailings[address] = mailing                
            

    def add_mailing_list(self, list_info={}):
        """
        Add a new mailing list to this postman instance. expects one parameter,
        list_info, which is a dictionary that should contain, at least, the
        following keys:

         - name: (string) the name we will give to the list
         - address: (string) the email address of the list
         - members: (list) a list of email adddress of the list members
         
        """
        if not isinstance(list_info, dict):
            raise TypeError(list_info, ' is not a valid dictionary')

        if 'name' not in list_info.keys() or \
           'address' not in list_info.keys() or \
           'members' not in list_info.keys():
            raise ValueError(list_info, ' does not seem to be a valid configuration')
        
        if list_info['address'] in self.mailings_addresses:
            raise IndexError(list_info['address'],
                             ' has been already added to postman')

        mailing = MailingList(list_info['name'], list_info['address'],
                              list_info['members'])        
        self.mailings[mailing.address] = mailing
        self.mailings_addresses.append(mailing.address)
        # After adding new mailings, save them to disk
        self.save()
        
    def add_mailing_member(self, member_addr=None, list_addr=None):
        """
        Add a new member for the mailing list represented by list_addr (a string
        containing the email address of any mailing list managed by this postman
        instance). member_addr is a string representing the email address of the
        new member
        """

        if not member_addr:
            raise ValueError(member_addr, 'missing member address')

        if not list_addr:
            raise ValueError(list_addr, 'missing list address')

        if list_addr not in self.mailings_addresses:
            # FIXME: Perhaps we should add it, perhaps not (mispelled address?)
            raise IndexError(list_addr, ' is not a valid mailing list')

        member = Member(member_addr)