from typing import List

import json
from datetime import datetime
from urllib.error import HTTPError
import traceback

import bottle
from isodate import Duration

from icalendar_timeseries_server.config import get_config
from icalendar_timeseries_server.event import Event
from icalendar_timeseries_server.cal import scrape_calendar
from icalendar_timeseries_server.query import MetricQuery


@bottle.route('/api/v1/query')
@bottle.route('/api/v1/query_range')
def prometheus_api():
    tz = get_config().tz
    now: datetime = datetime.now(tz)
    start_delta: Duration = get_config().start_delta
    end_delta: Duration = get_config().end_delta
    start: datetime = now + start_delta
    end: datetime = now + end_delta
    events: List[Event] = []

    try:
        q = MetricQuery(bottle.request.query['query'])
    except ValueError as e:
        response = {
            'status': 'error',
            'errorType': 'bad_data',
            'error': str(e)
        }
        bottle.response.status = 400
        traceback.print_exc()
        bottle.response.add_header('Content-Type', 'application/json')
        return json.dumps(response)

    try:
        for name, caldef in get_config().calendars.items():
            events.extend(scrape_calendar(name, caldef, start, end))
        events = list(filter(q, events))
        events.sort(key=lambda e: e.start)
        response = {
            'status': 'success',
            'data': {
                'resultType': 'vector',
                'result': [e.serialize() for e in events]
            }
        }
    except HTTPError as e:
        response = {
            'status': 'error',
            'errorType': 'internal',
            'error': str(e)
        }
        bottle.response.status = 500
        traceback.print_exc()
    except BaseException:
        response = {
            'status': 'error',
            'errorType': 'internal',
            'error': 'An internal error occurred.'
        }
        bottle.response.status = 500
        traceback.print_exc()

    bottle.response.add_header('Content-Type', 'application/json')
    return json.dumps(response)