import datetime

from apiflask import APIBlueprint
from flask import Response, abort, current_app, make_response

from ...base.mode import EnrollmentsMode
from ...base.schemas import MessageSchema
from ...base.utils import paginate_models
from ...dependencies import db
from ...examination_schedule.models import ExaminationSchedule, TermOfDefence
from ...project_supervisor.models import ProjectSupervisor
from ...students.models import Group, YearGroup
from ..query.enrollments import set_enrollments_mode
from ..schemas.examination_schedule import (
    ExaminationScheduleSchema,
    ExaminationSchedulesPaginationSchema,
    ExaminationSchedulesQuerySchema,
)
from ..utils import generate_examination_schedule_pdf_file, get_duration_time

bp = APIBlueprint("examination_schedule", __name__, url_prefix="/examination_schedule")


@bp.get("/<int:year_group_id>/")
@bp.input(ExaminationSchedulesQuerySchema, location="query")
@bp.output(ExaminationSchedulesPaginationSchema)
def list_examination_schedule(year_group_id: int, query: dict) -> dict:
    page = query.get("page")
    per_page = query.get("per_page")
    es_query = ExaminationSchedule.query.filter(
        ExaminationSchedule.year_group_id == year_group_id
    )
    data = paginate_models(page, es_query, per_page)
    return {"examination_schedules": data["items"], "max_pages": data["max_pages"]}


@bp.post("/<int:year_group_id>/")
@bp.input(ExaminationScheduleSchema)
@bp.output(MessageSchema, status_code=201)
def create_examination_schedule(year_group_id: int, data: dict) -> dict:
    yg = YearGroup.query.filter(YearGroup.id == year_group_id).first()
    if yg is None:
        abort(404, "Year group doesn't exist!")

    if data.get("start_date") > data.get("end_date"):
        abort(400, "Invalid data! End date must be greater than start date!")

    duration_time = get_duration_time(yg.mode)
    if duration_time is None:
        abort(400, "Invalid duration time!")

    examination_schedule = ExaminationSchedule(
        **data, year_group_id=year_group_id, duration_time=duration_time
    )
    db.session.add(examination_schedule)
    db.session.commit()
    return {"message": "Examination schedule was created!"}


@bp.put("/<int:examination_schedule_id>/")
@bp.input(ExaminationScheduleSchema)
@bp.output(MessageSchema)
def update_examination_schedule(examination_schedule_id: int, data: dict) -> dict:
    examination_schedule_query = db.session.query(ExaminationSchedule).filter(
        ExaminationSchedule.id == examination_schedule_id
    )
    examination_schedule = examination_schedule_query.first()

    if examination_schedule is None:
        abort(404, "Examination schedule doesn't exist!")
    examination_schedule_query.update(data)
    db.session.commit()
    return {"message": "Examination schedule was updated!"}


@bp.delete("/<int:examination_schedule_id>/")
@bp.output(MessageSchema)
def delete_examination_schedule(examination_schedule_id: int) -> dict:
    examination_schedule = (
        db.session.query(ExaminationSchedule)
        .filter(ExaminationSchedule.id == examination_schedule_id)
        .first()
    )
    if examination_schedule is None:
        abort(404, "Examination schedule doesn't exist!")
    db.session.delete(examination_schedule)
    db.session.commit()
    return {"message": "Examination schedule was deleted!"}


@bp.put("/<int:examination_schedule_id>/open-enrollments/")
@bp.output(MessageSchema)
def open_enrollments(examination_schedule_id: int) -> dict:
    return set_enrollments_mode(examination_schedule_id, EnrollmentsMode.OPEN, "open")


@bp.put("/<int:examination_schedule_id>/close-enrollments/")
@bp.output(MessageSchema)
def close_enrollments(examination_schedule_id: int) -> dict:
    return set_enrollments_mode(examination_schedule_id, EnrollmentsMode.CLOSE, "close")


@bp.post("/<int:examination_schedule_id>/download/")
def download_examination_schedule(examination_schedule_id: int) -> Response:
    examination_schedule = (
        db.session.query(ExaminationSchedule)
        .filter(ExaminationSchedule.id == examination_schedule_id)
        .first()
    )

    if examination_schedule is None:
        abort(404, "Examination schedule doesn't exist!")

    distinct_dates = (
        db.session.query(db.func.Date(TermOfDefence.start_date)).distinct().all()
    )

    nested_term_of_defences = []
    for d in distinct_dates:
        date_tmp = datetime.datetime.strptime(d[0], "%Y-%m-%d").date()
        term_of_defences = (
            db.session.query(TermOfDefence)
            .join(Group, isouter=True)
            .join(ProjectSupervisor, isouter=True)
            .filter(TermOfDefence.examination_schedule_id == examination_schedule_id)
            .filter(TermOfDefence.group_id.isnot(None))
            .filter(db.func.Date(TermOfDefence.start_date) == date_tmp)
            .all()
        )
        if len(term_of_defences) > 0:
            nested_term_of_defences.append(term_of_defences)
    # print(nested_term_of_defences)
    base_dir = current_app.config.get("BASE_DIR")
    pdf = generate_examination_schedule_pdf_file(
        examination_schedule.title, nested_term_of_defences, base_dir
    )
    title = examination_schedule.title.replace("-", "_").split()
    filename = "_".join(title)

    response = make_response(pdf)
    response.headers["Content-Type"] = "application/pdf"
    response.headers["Content-Disposition"] = "attachment; filename=%s.pdf" % filename
    return response