from __future__ import print_function

import json
import re
import sys

from pprint import pformat
from traceback import print_exc
from wsgiref.simple_server import make_server


class PersonModel(object):
    __people__ = [
        {
            'name': {
                'first': 'Hammy',
                'last': 'Spammy',
            },
            'age': 42,
            'id': 1,
        },
        {
            'name': {
                'first': 'Sampers',
                'last': 'Dancer',
            },
            'age': 38,
            'id': 2
        },
    ]

    def __init__(self):
        self._index()

    def _index(self):
        self.__people_by_id__ = dict(((p['id'], p) for p in self.__people__))

    def getall(self):
        return self.__people__

    def get(self, person_id):
        return self.__people_by_id__[person_id]

    def add(self, person):
        person['id'] = len(self.__people__) + 1
        self.__people__.append(person)
        self._index()
        return person['id']


class PersonApp(object):
    __routes__ = [
        (_m, _k, re.compile('^{}$'.format(_k)), _v) for _m, _k, _v in (
            ('GET', '/people.json', 'all'),
            ('POST', '/people.json', 'new'),
            ('GET', '/people/(.*)\.json', 'get'),
            ('GET', '/', 'echo')
        )
    ]

    def __init__(self):
        self.people = PersonModel()
        print('Routes = {}'.format(pformat(self.__routes__)))

    def __call__(self, environ, start_response):
        path = '/' + environ.get('PATH_INFO', '').lstrip('/')
        request_method = environ.get('REQUEST_METHOD', 'GET')

        environ.update({
            'app.path': path,
            'app.request_method': request_method,
        })

        method_name = 'not_found'
        for route_req_method, route, route_re, route_method in self.__routes__:
            if route_req_method == request_method:
                match = route_re.match(path)
                if match:
                    print('Found match: {!r}'.format(match.re.pattern))
                    environ['app.route_match'] = match
                    method_name = route_method
                    break

        try:
            return getattr(self, method_name)(environ, start_response)
        except AttributeError, exc:
            print_exc()
            return self.not_found(environ, start_response)

    def not_found(self, environ, start_response):
        print('Nothing matched: {} {!r}'.format(
            environ['app.request_method'], environ['app.path']
        ))
        return self._return_json(
            start_response, {'error': 'Not Found'},
            status='404 Not Found'
        )

    def bad_request(self, environ, start_response):
        return self._return_json(
            start_response, {'error': 'Bad Request'},
            status='400 Bad Request'
        )

    def get(self, environ, start_response):
        person_id = environ['app.route_match'].group(1)
        if not person_id.isdigit():
            return self.bad_request(environ, start_response)

        person = self.people.get(int(person_id))
        return self._return_json(start_response, {'person': person})

    def all(self, environ, start_response):
        return self._return_json(start_response, self.people.getall())

    def new(self, environ, start_response):
        person = json.loads(
            environ['wsgi.input'].read(int(environ['CONTENT_LENGTH']))
        )
        person_id = self.people.add(person)
        return self._return_json(
            start_response, {}, status='201 Created',
            extra_headers=[
                ('location', '/people/{}.json'.format(person_id))
            ]
        )

    def echo(self, environ, start_response):
        return self._return_json(start_response, {'here?': 'yup'})

    def _return_json(self, start_response, json_dict, status='200 OK',
                     extra_headers=()):
        body = json.dumps(json_dict)
        start_response(status, [
            ('content-type', 'application/x-json'),
            ('content-length', str(len(body)))
        ] + list(extra_headers))
        return [body]


def main():
    server = make_server('0.0.0.0', 9282, PersonApp())
    try:
        print('Serving on 0.0.0.0:9282')
        server.serve_forever()
        return 1
    except KeyboardInterrupt:
        return 0


if __name__ == '__main__':
    sys.exit(main())