from io import BytesIO
from itertools import groupby
from operator import attrgetter
from typing import Union

import structlog
from django.http import HttpResponse
from openpyxl import Workbook

from vbv_lernwelt.core.models import User
from vbv_lernwelt.course.models import CourseCompletionStatus, CourseSession
from vbv_lernwelt.course.services import mark_course_completion
from vbv_lernwelt.course_session.services.export import (
    make_export_filename,
    sanitize_sheet_name,
)
from vbv_lernwelt.feedback.models import FeedbackResponse
from vbv_lernwelt.learnpath.models import (
    LearningContentFeedbackUK,
    LearningContentFeedbackVV,
)

logger = structlog.get_logger(__name__)

VV_FEEDBACK_QUESTIONS = [
    ("satisfaction", "Zufriedenheit insgesamt"),
    ("goal_attainment", "Zielerreichung insgesamt"),
    (
        "proficiency",
        "Wie beurteilst du deine Sicherheit bezüglichen den Themen nach dem Circle?",
    ),
    ("preparation_task_clarity", "Waren die Praxisaufträge klar und verständlich?"),
    ("would_recommend", "Würdest du den Circle weiterempfehlen?"),
    ("course_positive_feedback", "Was hat dir besonders gut gefallen?"),
    ("course_negative_feedback", "Wo siehst du Verbesserungspotential?"),
]

UK_FEEDBACK_QUESTIONS = [
    ("satisfaction", "Zufriedenheit insgesamt"),
    ("goal_attainment", "Zielerreichung insgesamt"),
    (
        "proficiency",
        "Wie beurteilst du deine Sicherheit bezüglichen den Themen nach dem Kurs?",
    ),
    (
        "preparation_task_clarity",
        "Waren die Vorbereitungsaufträge klar und verständlich?",
    ),
    (
        "instructor_competence",
        "Wie beurteilst du die Themensicherheit und Fachkompetenz des Kursleiters/der Kursleiterin?",
    ),
    (
        "instructor_respect",
        "Wurden Fragen und Anregungen der Kursteilnehmenden ernst genommen und aufgegriffen?",
    ),
    (
        "instructor_open_feedback",
        "Was möchtest du dem Kursleiter/der Kursleiterin sonst noch sagen?",
    ),
    ("would_recommend", "Würdest du den Kurs weiterempfehlen?"),
    ("course_positive_feedback", "Was hat dir besonders gut gefallen?"),
    ("course_negative_feedback", "Wo siehst du Verbesserungspotential?"),
]


def update_feedback_response(
    feedback_user: User,
    course_session: CourseSession,
    learning_content_feedback_page: Union[
        LearningContentFeedbackUK, LearningContentFeedbackVV
    ],
    submitted: bool,
    validated_data: dict,
):
    circle = learning_content_feedback_page.get_circle()

    feedback_response, _ = FeedbackResponse.objects.get_or_create(
        feedback_user_id=feedback_user.id,
        circle_id=circle.id,
        course_session=course_session,
    )

    original_data = feedback_response.data
    updated_data = validated_data
    initial_data = initial_data_for_feedback_page(learning_content_feedback_page)

    merged_data = initial_data | {
        key: (
            updated_data[key]
            if updated_data.get(key, "") != ""
            else original_data.get(key)
        )
        for key in initial_data.keys()
    }

    feedback_response.data = merged_data

    # save the response before completion mark,
    # because who knows what could happen in between...
    if submitted:
        feedback_response.submitted = submitted
    feedback_response.save()

    if submitted:
        mark_course_completion(
            user=feedback_user,
            page=learning_content_feedback_page,
            course_session=course_session,
            completion_status=CourseCompletionStatus.SUCCESS.value,
        )

    logger.info(
        "feedback successfully created",
        label="feedback",
        feedback_user_id=feedback_user.id,
        circle_title=circle.title,
        course_session_id=course_session.id,
    )

    return feedback_response


def initial_data_for_feedback_page(
    learning_content_feedback_page: Union[
        LearningContentFeedbackUK, LearningContentFeedbackVV
    ]
):
    if hasattr(learning_content_feedback_page, "learningcontentfeedbackuk"):
        return {
            "satisfaction": None,
            "goal_attainment": None,
            "proficiency": None,
            "preparation_task_clarity": None,
            "instructor_competence": None,
            "instructor_respect": None,
            "instructor_open_feedback": "",
            "would_recommend": None,
            "course_negative_feedback": "",
            "course_positive_feedback": "",
            "feedback_type": "uk",
        }
    if hasattr(learning_content_feedback_page, "learningcontentfeedbackvv"):
        return {
            "satisfaction": None,
            "goal_attainment": None,
            "proficiency": None,
            "preparation_task_clarity": None,
            "would_recommend": None,
            "course_negative_feedback": "",
            "course_positive_feedback": "",
            "feedback_type": "vv",
        }
    return {}


def export_feedback(course_session_ids: list[str], save_as_file: bool, circles=None):
    wb = Workbook()

    # remove the first sheet is just easier than keeping track of the active sheet
    wb.remove(wb.active)

    if circles:
        feedback_unordered = FeedbackResponse.objects.filter(
            course_session_id__in=course_session_ids,
            circle__in=circles,
            submitted=True,
        )
    else:
        feedback_unordered = FeedbackResponse.objects.filter(
            course_session_id__in=course_session_ids,
            submitted=True,
        )

    feedbacks = feedback_unordered.order_by("circle", "course_session", "updated_at")
    grouped_feedbacks = groupby(feedbacks, key=attrgetter("circle"))

    for circle, group_feedbacks in grouped_feedbacks:
        group_feedbacks = list(group_feedbacks)
        logger.debug(
            "export_feedback_for_circle",
            data={
                "circle": circle.id,
                "course_session_ids": course_session_ids,
                "count": len(group_feedbacks),
            },
            label="feedback_export",
        )
        _create_sheet(wb, circle.title, group_feedbacks)

    if save_as_file:
        wb.save(make_export_filename(name="feedback_export"))
    else:
        output = BytesIO()
        wb.save(output)

        output.seek(0)
        return output.getvalue()


def _create_sheet(wb: Workbook, title: str, data: list[FeedbackResponse]):
    sheet = wb.create_sheet(title=sanitize_sheet_name(title))

    if len(data) == 0:
        return sheet

    # we instruct the users not to mix exports of different courses, so we can assume the questions are the same and of the first type
    question_data = (
        UK_FEEDBACK_QUESTIONS
        if data[0].data["feedback_type"] == "uk"
        else VV_FEEDBACK_QUESTIONS
    )

    # add header
    sheet.cell(row=1, column=1, value="Durchführung")
    sheet.cell(row=1, column=2, value="Datum")
    questions = [q[1] for q in question_data]
    for col_idx, title in enumerate(questions, start=3):
        sheet.cell(row=1, column=col_idx, value=title)

    _add_rows(sheet, data, question_data)
    return sheet


def _add_rows(sheet, data, question_data):
    for row_idx, feedback in enumerate(data, start=2):
        sheet.cell(row=row_idx, column=1, value=feedback.course_session.title)
        sheet.cell(
            row=row_idx, column=2, value=feedback.updated_at.date().strftime("%d.%m.%Y")
        )
        for col_idx, question in enumerate(question_data, start=3):
            response = feedback.data.get(question[0], "")
            sheet.cell(row=row_idx, column=col_idx, value=response)


# used as admin action, that's why it's not in the views.py
def get_feedbacks_for_course_sessions(_modeladmin, _request, queryset):
    file_name = "feedback_export_durchfuehrungen"
    return _handle_feedback_export_action(queryset, file_name)


def get_feedbacks_for_courses(_modeladmin, _request, queryset):
    course_sessions = CourseSession.objects.filter(course__in=queryset)
    file_name = "feedback_export_lehrgaenge"
    return _handle_feedback_export_action(course_sessions, file_name)


def _handle_feedback_export_action(course_seesions, file_name):
    excel_bytes = export_feedback(course_seesions, False)

    response = HttpResponse(
        content_type="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"
    )
    response[
        "Content-Disposition"
    ] = f"attachment; filename={make_export_filename(file_name)}"
    response.write(excel_bytes)

    return response