#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import os
import sys
import yaml
import logging
try:
    from yaml import CLoader as Loader, CDumper as Dumper
except ImportError:
    from yaml import Loader, Dumper

import click

from adapters import *

logger = logging.getLogger(f'wp_cal.{__name__}')

class BaseConfig(dict):

    def __init__(self, file, defaults, *args, **kwargs):
        self._ex = None
        self.file = file
        self.defaults = defaults
        super().__init__(*args, **kwargs)
        try:
            self._load()
        except FileNotFoundError as ex:
            self._ex = ex

    def __repr__(self):
        return super().__repr__()

    def __str__(self):
        return super().__str__()

    def _load(self):
        try:
            if self.file == '-':
                config = yaml.load(sys.stdin, Loader=Loader)
            else:
                with open(self.file) as fp:
                    config = yaml.load(fp, Loader=Loader)
            if config is None:
                config = {}
            for k, v in config.items():
                self[k] = v
        finally:
            for keylist, value  in self.defaults:
                d = self
                for i, key in enumerate(keylist):
                    repl = value if (i == len(keylist) - 1) else {}
                    d[key] = d.get(key, repl)
                    d = d[key]

    def _save(self):
        with open(self.file, 'w') as fp:
            yaml.dump(self, fp, Dumper=Dumper)

    def exception(self):
        return self._ex

    def load(self):
        return self._load()

    def save(self):
        return self._save()

class Config(BaseConfig):
    """
    The default configuration.


    Keys:
    .google.calendar_id: the id of the calendar to sync
    .google.credentials: the json of the obtained credentials file
    .google.token_file: where to save the login token
    .wordpress.url: the base wordpress url
    .wordpress.calendar.id: the id of the (wp-booking-system) calendar
    .wordpress.calendar.name: the name of the calendar
    .wordpress.calendar.translations: a dictionary of language <-> translation pairs (example: {"en": "Reservations"})
    .wordpress.credentials.user: the user as which to log into wordpress
    .wordpress.credentials.password: the users password
    .logging.level: one or more log levels of the form <module.submodule>:<level> seperated by a `,` (comma)
    """

    def __init__(self, file, defaults, *args, **kwargs):
        defaults += [
            ('google.calendar_id', '#TODO insert google calendar id'),
            ('google.credentials', {}),
            ('google.token_file', os.path.join(os.environ['HOME'], '.wp-cal-google-token')),
            ('wordpress.url', '#TODO insert url to wordpress site'),
            ('wordpress.calendar.id', '#TODO insert wp-booking-system calendar id'),
            ('wordpress.calendar.name', '#TODO insert calendar name'),
            ('wordpress.calendar.translations', {'en': '#TODO insert english translation'}),
            ('wordpress.credentials.user', '#TODO insert wordpress username'),
            ('wordpress.credentials.password', '#TODO insert wordpress password'),
        ]
        defaults = [(x[0].split('.'), x[1]) for x in defaults]
        super().__init__(file, defaults, *args, **kwargs)

def init_logging(level: str):
    allowed_values = {'NOTSET', 'DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'}

    log_levels = [x.split(':') for x in level.split(',')]
    for module, level in log_levels:
        module = module.strip() if module else None
        level = level.strip().upper()
        if level not in allowed_values:
            raise ValueError(f'invalid log level, allowed values: {repr(allowed_values)}')
        level = getattr(logging, level)
        logging.getLogger(module).setLevel(level)

@click.command()
@click.option('--level', '-l', envvar='WP_CAL_LEVEL', default=':WARNING,wp_cal:INFO', help='The log level for the application')
@click.option('--config', '-c', envvar='WP_CAL_CONFIG', default='-', help='The configuration file')
def main(level, config):
    logging.basicConfig()
    init_logging(level)

    config = Config(config, [('logging.level', ':WARNING,wp_cal:INFO')])
    if config.exception():
        logger.info('config not found, trying to generate template')
        try:
            config.save()
        except Exception:
            logger.exception('failed to generate template')
        else:
            logger.info('generated config at "%s"', config.file)
        return

    init_logging(config['logging']['level'])

    g = Google(
        config['google']['calendar_id'],
        credentials=config['google']['credentials'],
        token_file=config['google']['token_file'],
    )
    w = Wordpress(
        config['wordpress']['url'],
        calendar_metadata=CalendarMetadata(
            id=config['wordpress']['calendar']['id'],
            name=config['wordpress']['calendar']['name'],
            translations=config['wordpress']['calendar']['translations'],
        ),
        credentials=config['wordpress']['credentials'],
    )
    g.login()
    events = g.get_events()
    logger.info("syncing %d events", len(events))
    w.login()
    w.post_events(events)
    logger.info("done")

if __name__ == '__main__':
    main()