import datetime

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

from ...base.utils import paginate_models
from ...dependencies import db
from ...examination_schedule.models import ExaminationSchedule, Enrollment
from ...students.models import Group
from ...project_supervisor.models import ProjectSupervisor
from ..schemas import ExaminationScheduleSchema, ExaminationScheduleUpdateSchema, MessageSchema, \
    ExaminationSchedulesQuerySchema, ExaminationSchedulesPaginationSchema
from ..utils import generate_examination_schedule_pdf_file

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


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


@bp.post('/')
@bp.input(ExaminationScheduleSchema)
@bp.output(MessageSchema)
def create_examination_schedule(data: dict) -> dict:
    examination_schedule = ExaminationSchedule(**data)
    db.session.add(examination_schedule)
    db.session.commit()
    return {"message": "Examination schedule was created!"}


@bp.put('/<int:id>/')
@bp.input(ExaminationScheduleSchema)
@bp.output(MessageSchema)
def update_title_examination_schedule(id: int, data: dict) -> dict:
    examination_schedule_query = db.session.query(ExaminationSchedule).filter(ExaminationSchedule.id == 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:id>/')
@bp.output(MessageSchema)
def delete_examination_schedule(id: int) -> dict:
    examination_schedule = db.session.query(ExaminationSchedule).filter(ExaminationSchedule.id == 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:id>/date')
@bp.input(ExaminationScheduleUpdateSchema)
@bp.output(MessageSchema)
def set_date_of_examination_schedule(id: int, data: dict) -> dict:
    examination_schedule_query = db.session.query(ExaminationSchedule).filter(ExaminationSchedule.id == id)
    examination_schedule = examination_schedule_query.first()

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

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

    examination_schedule_query.update(data)
    db.session.commit()
    return {"message": "You set date of examination schedule!"}


@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(Enrollment.start_date)).distinct().all()
    # print(distinct_dates)
    nested_enrollments = []
    for d in distinct_dates:
        date_tmp = datetime.datetime.strptime(d[0], "%Y-%m-%d").date()
        enrollment = db.session.query(Enrollment).join(ExaminationSchedule, isouter=True).\
            join(Group, isouter=True).join(ProjectSupervisor, isouter=True). \
            filter(ExaminationSchedule.id == examination_schedule_id).filter(
            db.func.Date(Enrollment.start_date) == date_tmp).all()
        nested_enrollments.append(enrollment)

    # print(nested_enrollments)
    pdf = generate_examination_schedule_pdf_file(examination_schedule.title, nested_enrollments)
    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