from canvasapi import Canvas
import itertools
import random

API_URL = "https://canvas.instructure.com"
API_KEY = <your api key here>

canvas = Canvas(API_URL, API_KEY)

# create a calculated_question
# example of a potential divider
#
#  U2 = U0 * R2 / ( R1 + R2 )
#

E3  = [1, 2, 5]
E6  = [1.0, 1.5, 2.2, 3.3, 4.7, 6.8]
E12 = [1.0, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9, 4.7, 5.6, 6.8, 8.2]

coursename = 'test'
quizname   = 'test'

# define the input variable names
#   each variable has its own range, format and scale
#   
variables = \
    [
      {
        'name':   'U0',
        'unit':   'V',
        'format': '{:.1f}',
        'scale':  '1',
        'range':  [1.2, 1.5, 4.5, 9, 12, 24, 48, 110, 220]
      },
      {
        'name':   'R1',
        'unit':   'ohm',
        'format': '{:.1f}',
        'scale':  '1',
        'range':  [ i*j for i, j in itertools.product([10, 100, 1000], E12)]
      },
      {
        'name':   'R2',
        'unit':   'ohm',
        'format': '{:.1f}',
        'scale':  '1',
        'range':  [ i*j for i, j in itertools.product([10, 100, 1000], E12)]
      },
    ]

# how many sets of answers
rows = 30

# create an empty list of lists (array) for the values
values = [ [ i for i in range(len(variables))] for _ in range(rows)]

# create an empty list for the calculated results
results = [i for i in range(rows)]

# fill the array of input values with random choices from the given ranges
for i in range(rows):
    for j in range(len(variables)):
        values[i][j] = random.choice(variables[j].get('range'))

    # and calculate the result value    
    results[i] = values[i][0] * values[i][2] / (values[i][1]+values[i][2])

# format the text field for the question
#   an HTML table is created which presents the variables and their values
question_text = '<p><table border="1"><tr><th></th><th>value</th><th>unit</th></tr>';
for j in range(len(variables)):
    question_text += '<tr>'
    question_text += '<td style="text-align:center;">' + variables[j].get('name') + '</td>'
    question_text += '<td style="text-align:right;">[' + variables[j].get('name') + ']</td>'
    question_text += '<td style="text-align:center;">' + variables[j].get('unit') + '</td>'
    question_text += '</tr>'
question_text += '</table></p>'

# format the central block of values and results
answers = []
for i in range(rows):
    answers.append(\
        {
          'weight': '100',
          'variables':
          [
            {
              'name': variables[j].get('name'),
              'value': variables[j].get('format').format(values[i][j])
            } for j in range(len(variables))
          ],
          'answer_text': '{:.5g}'.format(results[i])
        })

# format the block of variables,
#   'min' and 'max' do not matter since the values are created inside the script
#   'scale' determines the decimal places during output  
variables_block = []
for j in range(len(variables)):
    variables_block.append(\
        {
          'name':  variables[j].get('name'),
          'min':   '1.0',
          'max':   '10.0',
          'scale': variables[j].get('scale')
        })

# put together the structure of the question
new_question = \
    {
      'question_name':           'Question 6',
      'question_type':           'calculated_question',
      'question_text':           question_text,
      'points_possible':         '1.0',
      'correct_comments':        '',
      'incorrect_comments':      '',
      'neutral_comments':        '',
      'correct_comments_html':   '',
      'incorrect_comments_html': '',
      'neutral_comments_html':   '',
      'answers':                 answers,
      'variables':               variables_block,
      'formulas':                ['automated by python'],
      'answer_tolerance':        '5%',
      'formula_decimal_places':  '1',
      'matches':                 None,
      'matching_answer_incorrect_matches': None,
    }
                                  

courses  = canvas.get_courses()
for course in courses:
    if course.name.lower() == coursename.lower():
        print('found course')
        quizzes = course.get_quizzes()
        for quiz in quizzes:
            if quiz.title.lower() == quizname.lower():
                print('found quiz')

                question = quiz.create_question(question = new_question)