from typing import Dict, Any

import structlog
from openpyxl.reader.excel import load_workbook

from vbv_lernwelt.core.models import User
from vbv_lernwelt.course.models import Course, CourseSession, CourseSessionUser
from vbv_lernwelt.importer.utils import try_parse_datetime, parse_circle_group_string
from vbv_lernwelt.learnpath.models import LearningContentAttendanceCourse, Circle

logger = structlog.get_logger(__name__)


def create_or_update_user(
    email: str, first_name: str = "", last_name: str = "", sso_id: str = None
):
    logger.debug(
        "create_or_update_user",
        email=email,
        first_name=first_name,
        last_name=last_name,
        sso_id=sso_id,
        label="import",
    )
    user = None
    if sso_id:
        user_qs = User.objects.filter(sso_id=sso_id)
        if user_qs.exists():
            user = user_qs.first()

    if not user:
        user_qs = User.objects.filter(email=email)
        if user_qs.exists():
            user = user_qs.first()

    if not user:
        # create user
        user = User(sso_id=sso_id, email=email, username=email)

    user.email = email
    user.sso_id = user.sso_id or sso_id
    user.username = email
    user.first_name = first_name
    user.last_name = last_name
    user.set_unusable_password()
    user.save()

    return user


def import_course_sessions_from_excel(course: Course, filename: str):
    workbook = load_workbook(filename=filename)
    sheet = workbook["Schulungen Durchführung"]

    header = [cell.value for cell in sheet[1]]

    for row in sheet.iter_rows(min_row=2, values_only=True):
        row_with_header = list(zip(header, row))
        cs = create_or_update_course_session(
            course, dict(row_with_header), circles=["Fahrzeug"]
        )


def create_or_update_course_session(course: Course, data: Dict[str, Any], circles=None):
    """
    :param data: the following keys are required to process the data: Generation, Region, Klasse
    :return:
    """

    logger.debug(
        "create_or_update_course_session",
        course=course.title,
        data=data,
        label="import",
    )

    if circles is None:
        circles = []

    # TODO: validation
    group = data["Klasse"].strip()
    import_id = data["ID"].strip()

    generation = str(data["Generation"]).strip()
    region = data["Region"].strip()

    title = f"{region} {generation} {group}"

    cs, _created = CourseSession.objects.get_or_create(
        import_id=import_id, group=group, course=course
    )

    cs.additional_json_data["import_data"] = data
    cs.save()

    cs.title = title
    cs.generation = generation
    cs.region = region
    cs.group = group
    cs.import_id = import_id

    cs.save()

    for circle in circles:
        attendance_course_lp_qs = LearningContentAttendanceCourse.objects.filter(
            slug=f"{course.slug}-lp-circle-{circle.lower()}-lc-präsenzkurs-{circle.lower()}"
        )
        if attendance_course_lp_qs.exists():
            cs.attendance_courses.append(
                {
                    "learningContentId": attendance_course_lp_qs.first().id,
                    "start": try_parse_datetime(data[f"{circle} Start"])[1].isoformat(),
                    "end": try_parse_datetime(data[f"{circle} Ende"])[1].isoformat(),
                    "location": data[f"{circle} Raum"],
                    "trainer": "",
                }
            )
            cs.save()

    return cs


def import_trainers_from_excel(course: Course, filename: str):
    workbook = load_workbook(filename=filename)
    sheet = workbook["Schulungen Trainer"]

    header = [cell.value for cell in sheet[1]]

    for row in sheet.iter_rows(min_row=2, values_only=True):
        row_with_header = list(zip(header, row))
        create_or_update_trainer(course, dict(row_with_header))


def create_or_update_trainer(course: Course, data: Dict[str, Any]):
    logger.debug(
        "create_or_update_trainer",
        course=course.title,
        data=data,
        label="import",
    )

    user = create_or_update_user(
        email=data["Email"],
        first_name=data["Vorname"],
        last_name=data["Name"],
    )

    # TODO: handle language

    import_id = data["Generation"].strip()
    groups = [g.strip() for g in data["Klasse"].strip().split(",")]

    # general expert handling
    for group in groups:
        course_session = CourseSession.objects.filter(
            import_id=import_id, group=group, course=course
        ).first()
        if course_session:
            csu, _created = CourseSessionUser.objects.get_or_create(
                course_session_id=course_session.id, user_id=user.id
            )
            csu.role = CourseSessionUser.Role.EXPERT
            csu.save()

    # circle expert handling
    circle_data = parse_circle_group_string(data["Circles"])
    for circle_string in circle_data:
        parts = circle_string.split("(", 1)
        circle_name = parts[0].strip()
        groups = [g.strip() for g in parts[1].rstrip(")").strip().split(",")]

        # print(circle_name, groups)
        for group in groups:
            course_session = CourseSession.objects.filter(
                import_id=import_id, group=group, course=course
            ).first()
            circle = Circle.objects.filter(
                slug=f"{course.slug}-lp-circle-{circle_name.lower()}"
            ).first()

            if course_session and circle:
                csu = CourseSessionUser.objects.filter(
                    course_session_id=course_session.id, user_id=user.id
                ).first()
                if csu:
                    csu.expert.add(circle)
                    csu.save()