from .data import randomise_list
from ..models import Entry
from ..tools.logs import write

from flask import request, session
from flask.helpers import abort, redirect, url_for
from sqlalchemy.exc import SQLAlchemyError

from functools import wraps

def parse_test_code(code):
    return code.replace('—', '').lower()

def generate_questions(dataset:list):
    output = []
    for block in randomise_list(dataset):
        if block['type'] == 'question':
            question = {
                'type': 'question',
                'q_no': block['q_no'],
                'question_header': '',
                'text': block['text']
            }
            if block['q_type'] == 'Multiple Choice': question['options'] = randomise_list([*enumerate(block['options'])])
            else: question['options'] = [*enumerate(block['options'])]
            output.append(question)
        elif block['type'] == 'block':
            for key, _question in enumerate(randomise_list(block['questions'])):
                question = {
                    'type': 'block',
                    'q_no': _question['q_no'],
                    'question_header': block['question_header'] if 'question_header' in block else '',
                    'block_length': len(block['questions']),
                    'block_q_no': key,
                    'text': _question['text']
                }
                if _question['q_type'] == 'Multiple Choice': question['options'] = randomise_list([*enumerate(_question['options'])])
                else: question['options'] = [*enumerate(_question['options'])]
                output.append(question)
    return output

def evaluate_answers(answers:dict, key:list):
    score = 0
    max = 0
    tags = {}
    for block in key:
        if block['type'] == 'question':
            max += 1
            q_no = block['q_no']
            if str(q_no) in answers:
                submitted_answer = int(answers[str(q_no)])
                if submitted_answer == block['correct']:
                    score += 1
                    for tag in block['tags']:
                        if tag not in tags:
                            tags[tag] = {
                                'scored': 1,
                                'max': 1
                            }
                        else:
                            tags[tag]['scored'] += 1
                            tags[tag]['max'] += 1
                else:
                    for tag in block['tags']:
                        if tag not in tags:
                            tags[tag] = {
                                'scored': 0,
                                'max': 1
                            }
                        else: tags[tag]['max'] += 1
            else:
                for tag in block['tags']:
                    if tag not in tags:
                        tags[tag] = {
                            'scored': 0,
                            'max': 1
                        }
                    else: tags[tag]['max'] += 1
        elif block['type'] == 'block':
            for question in block['questions']:
                max += 1
                q_no = question['q_no']
                if str(q_no) in answers:
                    submitted_answer = int(answers[str(q_no)])
                    if submitted_answer == question['correct']:
                        score += 1
                        for tag in question['tags']:
                            if tag not in tags:
                                tags[tag] = {
                                    'scored': 1,
                                    'max': 1
                                }
                            else:
                                tags[tag]['scored'] += 1
                                tags[tag]['max'] += 1
                    else:
                        for tag in question['tags']:
                            if tag not in tags:
                                tags[tag] = {
                                    'scored': 0,
                                    'max': 1
                                }
                            else: tags[tag]['max'] += 1
                else:
                    for tag in question['tags']:
                        if tag not in tags:
                            tags[tag] = {
                                'scored': 0,
                                'max': 1
                            }
                        else: tags[tag]['max'] += 1
    grade = 'merit' if score/max >= .85 else 'pass' if score/max >= .70 else 'fail'
    return {
        'grade': grade,
        'tags': tags,
        'score': score,
        'max': max
    }

def get_correct_answers(dataset:list):
    output = {}
    for block in dataset:
        if block['type'] == 'question':
            output[str(block['q_no'])] = block['correct']
        if block['type'] == 'block':
            for question in block['questions']:
                output[str(question['q_no'])] = question['correct']
    return output

def redirect_if_started(function):
    @wraps(function)
    def wrapper(*args, **kwargs):
        id = session.get('id')
        try:
            if request.method == 'GET' and id and Entry.query.filter_by(id=id).first(): return redirect(url_for('quiz._quiz'))
        except (SQLAlchemyError, ConnectionError) as exception:
            write('system.log', f'Database error when checking if test has been started: {exception}')
            return abort(500)
        return function(*args, **kwargs)
    return wrapper

def answer_options(dataset:list):
    output = []
    for block in dataset:
        if block['type'] == 'question':
            question = block['options'].copy()
            output.append(question)
        elif block['type'] == 'block':
            for _question in block['questions']:
                question = _question['options'].copy()
                output.append(question)
    return output