import logging
import os

import flask
import flask_login
import flask_restful
import flask_restful.fields
import flask_restful.reqparse
import itsdangerous
import sqlalchemy
import sqlalchemy.engine

from db import db, Member


app = flask.Flask(__name__)
app.logger.setLevel(logging.INFO)
app.config.update(
    ERROR_404_HELP=False,
    SQLALCHEMY_TRACK_MODIFICATIONS=False,
    SQLALCHEMY_DATABASE_URI=os.getenv('SQLALCHEMY_DATABASE_URI'),
    SECRET_KEY=os.getenv('SECRET_KEY'))

if app.config.get('SQLALCHEMY_DATABASE_URI', '').startswith('sqlite://'):
    @sqlalchemy.event.listens_for(sqlalchemy.engine.Engine, 'connect')
    def set_sqlite_pragma(dbapi_connection, connection_record):
        dbapi_connection.execute('PRAGMA journal_mode=WAL')
        dbapi_connection.execute('PRAGMA synchronous=NORMAL')

db.init_app(app)
db.create_all(app=app)

login_manager = flask_login.LoginManager()
login_manager.init_app(app)

api = flask_restful.Api(app)


member_fields = {
    'id': flask_restful.fields.String(),
    'nick': flask_restful.fields.String(),
    'x': flask_restful.fields.Float(),
    'y': flask_restful.fields.Float(),
    'created_at': flask_restful.fields.DateTime(dt_format='iso8601'),
    'updated_at': flask_restful.fields.DateTime(dt_format='iso8601'),
}
geometry_fields = {
    'type': flask_restful.fields.String(default='Point'),
    'coordinates': flask_restful.fields.List(flask_restful.fields.Float()),
}
properties_fields = {
    'id': flask_restful.fields.String(),
    'nick': flask_restful.fields.String(),
}
feature_fields = {
    'type': flask_restful.fields.String(default='Feature'),
    'geometry': flask_restful.fields.Nested(geometry_fields),
    'properties': flask_restful.fields.Nested(properties_fields),
}
features_fields = {
    'type': flask_restful.fields.String(default='FeatureCollection'),
    'features': flask_restful.fields.List(flask_restful.fields.Nested(feature_fields)),
}


member_parser = flask_restful.reqparse.RequestParser()
member_parser.add_argument('id', type=str, required=True)
member_parser.add_argument('nick', type=str, required=True)
member_parser.add_argument('x', type=float, required=True)
member_parser.add_argument('y', type=float, required=True)

filter_parser = flask_restful.reqparse.RequestParser()
filter_parser.add_argument('filter', type=str)
filter_parser.add_argument('sort_by', type=str)
filter_parser.add_argument('sort_order', type=str)
filter_parser.add_argument('page_number', type=int)
filter_parser.add_argument('page_size', type=int)

feature_parser = flask_restful.reqparse.RequestParser()
feature_parser.add_argument('type', type=str, required=True)
feature_parser.add_argument('geometry', type=dict, required=True)
feature_parser.add_argument('properties', type=dict, required=True)

geometry_parser = flask_restful.reqparse.RequestParser()
geometry_parser.add_argument('type', type=str, location=('geometry',), required=True)
geometry_parser.add_argument('coordinates', type=float, action='append',
                             location=('geometry',), required=True)

properties_parser = flask_restful.reqparse.RequestParser()
properties_parser.add_argument('id', type=str, location=('properties',), required=True)
properties_parser.add_argument('nick', type=str, location=('properties',), required=True)


@login_manager.request_loader
def load_user(request):
    key = request.headers.get('X-Members-API-Key')
    if not key:
        return None
    s = itsdangerous.TimedJSONWebSignatureSerializer(app.config['SECRET_KEY'])
    try:
        user = flask_login.UserMixin()
        user.id = s.loads(key)
        return user
    except (itsdangerous.SignatureExpired, itsdangerous.BadSignature):
        return None


def member2feature(member):
    return {
        'geometry': {
            'coordinates': [
                member.x,
                member.y,
            ],
        },
        'properties': {
            'id': member.id,
            'nick': member.nick,
        },
    }


def normalize(x, y):
    return x % 180 if x > 0 else x % -180, y


class MemberResource(flask_restful.Resource):
    @flask_restful.marshal_with(member_fields)
    def get(self, id):
        q = db.session.query(Member).filter(Member.id == id)
        member = q.first()
        if not member:
            flask_restful.abort(404, message='Member {0} does not exist'.format(id))
        return member, 200

    @flask_login.login_required
    @flask_restful.marshal_with(member_fields)
    def put(self, id):
        args = member_parser.parse_args()
        now = sqlalchemy.func.now()
        q = db.session.query(Member).filter(Member.id == id)
        member = q.first()
        if not member:
            member = Member(id=id, created_at=now)
        member.nick = args['nick']
        member.x, member.y = normalize(args['x'], args['y'])
        member.updated_at = now
        db.session.add(member)
        db.session.commit()
        return member, 200

    @flask_login.login_required
    def delete(self, id):
        q = db.session.query(Member).filter(Member.id == id)
        member = q.first()
        if not member:
            flask_restful.abort(404, message='Member {0} does not exist'.format(id))
        db.session.delete(member)
        db.session.commit()
        return None, 204


class MembersResource(flask_restful.Resource):
    @flask_restful.marshal_with(member_fields)
    def get(self):
        args = filter_parser.parse_args()
        q = db.session.query(Member)
        if args['filter']:
            q = q.filter(Member.nick.ilike('%{}%'.format(args['filter'])))
        count = q.count()
        if args['sort_order'] == 'random':
            q = q.order_by(sqlalchemy.func.random())
        elif args['sort_by']:
            col = getattr(Member, args['sort_by'], None)
            if col:
                if args['sort_order']:
                    order_by = getattr(col, args['sort_order'], None)
                    if order_by:
                        q = q.order_by(order_by())
                else:
                    q = q.order_by(col)
        if args['page_size']:
            q = q.limit(args['page_size'])
        if args['page_number'] and args['page_size']:
            q = q.offset(args['page_number'] * args['page_size'])
        members = q.all()
        return members, 200, {'X-Total-Count': count}

    @flask_login.login_required
    @flask_restful.marshal_with(member_fields)
    def post(self):
        args = member_parser.parse_args()
        if not args['id']:
            flask_restful.abort(400, message='Missing required parameter id')
        if not args['nick']:
            flask_restful.abort(400, message='Missing required parameter nick')
        if not args['x']:
            flask_restful.abort(400, message='Missing required parameter x')
        if not args['y']:
            flask_restful.abort(400, message='Missing required parameter y')
        now = sqlalchemy.func.now()
        q = db.session.query(Member).filter(Member.id == args['id'])
        member = q.first()
        if not member:
            member = Member(created_at=now)
        member.id = args['id']
        member.nick = args['nick']
        member.x, member.y = normalize(args['x'], args['y'])
        member.updated_at = now
        db.session.add(member)
        db.session.commit()
        url = api.url_for(MemberResource, id=member.id, _external=True, _scheme='https')
        return member, 201, {'Location': url}


class FeatureResource(flask_restful.Resource):
    @flask_restful.marshal_with(feature_fields)
    def get(self, id):
        q = db.session.query(Member).filter(Member.id == id)
        member = q.first()
        if not member:
            flask_restful.abort(404, message='Member {0} does not exist'.format(id))
        return member2feature(member), 200


class FeaturesResource(flask_restful.Resource):
    @flask_restful.marshal_with(features_fields)
    def get(self):
        q = db.session.query(Member)
        members = q.all()
        return {'features': [member2feature(m) for m in members]}, 200

    @flask_login.login_required
    @flask_restful.marshal_with(feature_fields)
    def post(self):
        feature_args = feature_parser.parse_args()
        geometry_args = geometry_parser.parse_args(req=feature_args)
        properties_args = properties_parser.parse_args(req=feature_args)
        if feature_args['type'] != 'Feature':
            flask_restful.abort(400, message='Unexpected feature type')
        if geometry_args['type'] != 'Point':
            flask_restful.abort(400, message='Unexpected geometry type')
        now = sqlalchemy.func.now()
        q = db.session.query(Member).filter(Member.id == properties_args['id'])
        member = q.first()
        if not member:
            member = Member(created_at=now)
        member.id = properties_args['id']
        member.nick = properties_args['nick']
        member.x, member.y = normalize(*geometry_args['coordinates'])
        member.updated_at = now
        db.session.add(member)
        db.session.commit()
        url = api.url_for(FeatureResource, id=member.id, _external=True, _scheme='https')
        return member2feature(member), 201, {'Location': url}


api.add_resource(MemberResource, '/members/<int:id>')
api.add_resource(MembersResource, '/members')
api.add_resource(FeatureResource, '/features/<int:id>')
api.add_resource(FeaturesResource, '/features')


if __name__ == '__main__':
    app.run(host='0.0.0.0', threaded=True, debug=False)