import falcon
import simplejson as json
import mysql.connector
import config
from core.useractivity import user_logger, access_control


class TimezoneCollection:
    @staticmethod
    def __init__():
        """"Initializes TimezoneCollection"""
        pass

    @staticmethod
    def on_options(req, resp):
        resp.status = falcon.HTTP_200

    @staticmethod
    def on_get(req, resp):
        cnx = mysql.connector.connect(**config.myems_system_db)
        cursor = cnx.cursor()

        query = (" SELECT id, name, description, utc_offset "
                 " FROM tbl_timezones ")
        cursor.execute(query)
        rows = cursor.fetchall()
        cursor.close()
        cnx.disconnect()

        result = list()
        if rows is not None and len(rows) > 0:
            for row in rows:
                meta_result = {"id": row[0], "name": row[1], "description": row[2], "utc_offset": row[3]}
                result.append(meta_result)

        resp.text = json.dumps(result)


class TimezoneItem:
    @staticmethod
    def __init__():
        """"Initializes TimezoneItem"""
        pass

    @staticmethod
    def on_options(req, resp, id_):
        resp.status = falcon.HTTP_200

    @staticmethod
    def on_get(req, resp, id_):
        if not id_.isdigit() or int(id_) <= 0:
            raise falcon.HTTPError(falcon.HTTP_400, title='API.BAD_REQUEST',
                                   description='API.INVALID_TIMEZONE_ID')

        cnx = mysql.connector.connect(**config.myems_system_db)
        cursor = cnx.cursor()

        query = (" SELECT id, name, description, utc_offset "
                 " FROM tbl_timezones "
                 " WHERE id = %s ")
        cursor.execute(query, (id_,))
        row = cursor.fetchone()
        if row is None:
            cursor.close()
            cnx.disconnect()
            raise falcon.HTTPError(falcon.HTTP_404, title='API.NOT_FOUND',
                                   description='API.TIMEZONE_NOT_FOUND')

        result = {"id": row[0], "name": row[1], "description": row[2], "utc_offset": row[3]}

        cursor.close()
        cnx.disconnect()

        resp.text = json.dumps(result)

    @staticmethod
    @user_logger
    def on_put(req, resp, id_):
        """Handles PUT requests"""
        access_control(req)
        try:
            raw_json = req.stream.read().decode('utf-8')
        except Exception as ex:
            raise falcon.HTTPError(falcon.HTTP_400, 'API.ERROR', ex)

        if not id_.isdigit() or int(id_) <= 0:
            raise falcon.HTTPError(falcon.HTTP_400, title='API.BAD_REQUEST',
                                   description='API.INVALID_TIMEZONE_ID')

        new_values = json.loads(raw_json)

        cnx = mysql.connector.connect(**config.myems_system_db)
        cursor = cnx.cursor()

        cursor.execute(" SELECT name "
                       " FROM tbl_timezones "
                       " WHERE id = %s ", (id_,))
        if cursor.fetchone() is None:
            cursor.close()
            cnx.disconnect()
            raise falcon.HTTPError(falcon.HTTP_404, title='API.NOT_FOUND',
                                   description='API.TIMEZONE_NOT_FOUND')

        update_row = (" UPDATE tbl_timezones "
                      " SET name = %s, description = %s, utc_offset = %s "
                      " WHERE id = %s ")
        cursor.execute(update_row, (new_values['data']['name'],
                                    new_values['data']['description'],
                                    new_values['data']['utc_offset'],
                                    id_,))
        cnx.commit()

        cursor.close()
        cnx.disconnect()

        resp.status = falcon.HTTP_200