from typing import Type

from vbv_lernwelt.assignment.models import (
    Assignment,
    AssignmentCompletion,
    AssignmentCompletionStatus,
)
from vbv_lernwelt.core.models import User
from vbv_lernwelt.core.utils import find_first
from vbv_lernwelt.course.models import CourseSession


def update_assignment_completion(
    user: User,
    assignment: Assignment,
    course_session: CourseSession,
    completion_data=None,
    completion_status: Type[AssignmentCompletionStatus] = "in_progress",
    copy_task_data: bool = False,
) -> AssignmentCompletion:
    """
    :param completion_data: should have the following structure:
       {
         "<user_text_input:uuid>": {"user_data": {"text": "some text from user"}},
         "<user_confirmation:uuid>": {"user_data": {"confirmation": true}},
       }
       every input field has the data stored in sub dict of the question uuid

       it can also contain "trainer_input" when the trainer has entered grading data
       {
         "<user_text_input:uuid>": {
           "trainer_data": {"points": 4, "text": "Gute Antwort"}
         },
       }
    :param copy_task_data: if true, the task data will be copied to the completion data
      used for "submitted" and "graded" status, so that we don't lose the question
      context
    :return: AssignmentCompletion
    """
    if completion_data is None:
        completion_data = {}

    ac, created = AssignmentCompletion.objects.get_or_create(
        user_id=user.id,
        assignment_id=assignment.id,
        course_session_id=course_session.id,
    )

    ac.completion_status = completion_status

    # TODO: make more validation of the provided input -> maybe with graphql
    completion_data = _remove_unknown_entries(assignment, completion_data)
    for key, value in completion_data.items():
        # retain already stored data
        stored_entry = ac.completion_data.get(key, {})
        stored_entry.update(value)
        ac.completion_data[key] = stored_entry

    if copy_task_data:
        # copy over the question data, so that we don't lose the context
        substasks = assignment.filter_user_subtasks()
        for key, value in ac.completion_data.items():
            task_data = find_first(substasks, pred=lambda x: x["id"] == key)
            ac.completion_data[key].update(task_data)

    ac.save()

    return ac


def _remove_unknown_entries(assignment, completion_data):
    """
    Removes all entries from completion_data which are not known to the assignment
    """
    possible_subtask_uuids = [
        subtask["id"] for subtask in assignment.filter_user_subtasks()
    ]
    filtered_completion_data = {
        key: value
        for key, value in completion_data.items()
        if key in possible_subtask_uuids
    }
    return filtered_completion_data