from ..models import Dataset, Entry, User
from ..tools.data import validate_json
from ..tools.logs import write
from ..tools.test import evaluate_answers, generate_questions

from flask import Blueprint, jsonify, request
from flask.helpers import abort, flash, url_for
from flask_login import login_required
from sqlalchemy.exc import SQLAlchemyError

from datetime import datetime, timedelta
from json import loads

api = Blueprint(
    name='api',
    import_name=__name__
)

@api.route('/questions/', methods=['POST'])
def _fetch_questions():
    id = request.get_json()['id']
    try: entry = Entry.query.filter_by(id=id).first()
    except (SQLAlchemyError, ConnectionError) as exception:
        write('system.log', f'Database error when processing request \'{request.url}\': {exception}')
        return abort(500)
    if not entry: return jsonify({'error': 'Invalid entry ID.'}), 400
    test = entry.test
    user_code = entry.user_code
    time_limit = test.time_limit
    time_adjustment = 0
    if time_limit:
        _time_limit = int(time_limit)
        if user_code:
            time_adjustment = test.adjustments[user_code]
            _time_limit += time_adjustment
        end_delta = timedelta(minutes=_time_limit)
        end_time = datetime.now() + end_delta
    else:
        end_time = None
    entry.start()
    dataset = test.dataset
    success, message = dataset.check_file()
    if not success: return jsonify({'error': message}), 500
    data_path = dataset.get_file()
    with open(data_path, 'r') as data_file:
        data = loads(data_file.read())
    questions = generate_questions(data)
    return jsonify({
        'time_limit': end_time,
        'questions': questions,
        'start_time': entry.start_time,
        'time_adjustment': time_adjustment
    }), 200

@api.route('/submit/', methods=['POST'])
def _submit_quiz():
    id = request.get_json()['id']
    answers = request.get_json()['answers']
    try: entry = Entry.query.filter_by(id=id).first()
    except (SQLAlchemyError, ConnectionError) as exception:
        write('system.log', f'Database error when processing request \'{request.url}\': {exception}')
        return abort(500)
    if not entry: return jsonify({'error': 'Unrecognised Entry.'}), 400
    test = entry.test
    dataset = test.dataset
    success, message = dataset.check_file()
    if not success: return jsonify({'error': message}), 500
    data_path = dataset.get_file()
    with open(data_path, 'r') as data_file:
        data = loads(data_file.read())
    result = evaluate_answers(answers=answers, key=data)
    entry.complete(answers=answers, result=result)
    return jsonify({
        'success': 'Your submission has been processed. Redirecting you to receive your results.',
        'id': id
    }), 200

@api.route('/editor/', methods=['POST'])
@login_required
def _editor(id:str=None):
    request_data = request.get_json()
    id = request_data['id']
    try:
        dataset = Dataset.query.filter_by(id=id).first()
        user = User.query.filter_by(id=creator).first()
    except SQLAlchemyError as exception:
        write('system.log', f'Database error when processing request \'{request.url}\': {exception}')
        return abort(500)
    if not dataset: return jsonify({'error': 'Invalid request. Dataset not found.'}), 404
    data_path = dataset.get_file()
    if request_data['action'] == 'fetch':
        with open(data_path, 'r') as data_file:
            data = loads(data_file.read())
        return jsonify({'success': 'Successfully downloaded dataset', 'data': data}), 200
    default = request_data['default']
    creator = request_data['creator']
    name = request_data['name']
    data = request_data['data']
    if not validate_json(data): return jsonify({'error': 'The data you submitted was invalid.'}), 400
    dataset.set_name(name)
    dataset.creator = user
    success, message = dataset.update(data=data, default=default)
    if not success: return jsonify({'error': message}), 400
    return jsonify({'success': message}), 200

@api.route('/editor/new/', methods=['POST'])
@login_required
def _editor_new():
    new_dataset = Dataset()
    new_dataset.set_name('New Dataset')
    success, message = new_dataset.create(data=[], default=False)
    if not success: return jsonify({'error':message}), 400
    flash(message, 'success')
    return jsonify({'success': message, 'redirect_to': url_for('editor._editor_console', id=new_dataset.id)}), 200