"""
Ownership change request message processing logic
=================================================

"""

from codecs import utf_8_decode
from datetime import datetime

from ytownership import config
from ytownership.connectors import mysql
from ytownership.connectors.sentry import sentry_client
from ytownership.logic import patch_ownership
from ytownership.models.apilog import YouTubeApiLog
from ytownership.validation.ownership import validate_sqs_message


class MessageProcessingResult:
    """Represents result of message processing

    Depending on response code of YouTube API we should create different
    message processing results. We could have both recoverable errors (e.g.
    YouTube API server error 500), and non-recoverable errors (e.g. 404).
    For recoverable errors, the processing of the message should be retried.
    """

    SUCCESS_STATUSES = [200]
    ERROR_STATUSES = [500, 401]
    FAILURE_STATUSES = [400, 403, 404]

    SUCCESS = 'success'
    FAILURE = 'failure'
    ERROR = 'error'

    @classmethod
    def get_processing_status(cls, status_code):
        """Maps status code, received from YouTube to MessageProcessingStatus

        Args:
            status_code (int): HTTP status code, received from YouTube

        Returns:
            str: SUCCESS, FAILURE or ERROR status
        """

        if status_code in cls.ERROR_STATUSES:
            return cls.ERROR
        elif status_code in cls.FAILURE_STATUSES:
            return cls.FAILURE
        elif status_code in cls.SUCCESS_STATUSES:
            return cls.SUCCESS
        return cls.FAILURE


def process_message(message):
    """Process ownership change request

    The processing consists of the following steps:
        1) Validate the message payload against schema
        2) Send a request to YouTube Content ID API
        3) Save results of YouTube API call
        4) return message processing result

    Args:
        message (JSONMessageExt): ownership change request message
    Returns:
        MessageProcessingResult
    """

    if not validate_sqs_message(message):
        return MessageProcessingResult.FAILURE
    response = patch_ownership.patch_ownership(message)
    save_result(message, response)
    result = MessageProcessingResult.get_processing_status(response.status)
    return result


def save_result(message, response):
    """Persists YouTube API call results to database

    Args:
        message (JSONMessageExt): ownership change request message
        response (Response): API call response
    """

    if response.status in MessageProcessingResult.SUCCESS_STATUSES\
            and not config.TRACK_SUCCESSFUL_API_CALLS:
        return True

    payload = message.get_body()
    try:
        with mysql.session_scope() as db_session:
            log = YouTubeApiLog()
            log.status = 'success' if response.status == 200 else 'error'
            log.territories = ','.join(payload['territories'])
            log.code = response.status
            log.content_owner_id = payload['content_owner_id']
            log.correlation_id = message.correlation_id
            log.created_date_utc = datetime.utcnow()
            log.isrc = payload['isrc']
            message = response.message
            if response.errors and type(response.errors) is bytes:
                message += ' errors: {0}' + utf_8_decode(response.errors)[0]
            log.message = message
            db_session.add(log)
    except Exception:
        if sentry_client:
            sentry_client.captureException()
        return False
    return True