import datetime

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

from ...base.utils import paginate_models
from ...base.mode import ModeGroups
from ...dependencies import db
from ...examination_schedule.models import ExaminationSchedule, TermOfDefence
from ...students.models import Group, YearGroup
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('/<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['start_date'] > data['end_date']:
        abort(400, "Invalid data! End date must be greater than start date!")

    duration_time = None
    if yg.mode == ModeGroups.NON_STATIONARY.value:
        duration_time = 20
    elif yg.mode in [ModeGroups.STATIONARY.value, ModeGroups.ENGLISH_SPEAKING_STATIONARY.value]:
        duration_time = 30

    if duration_time is None:
        abort(400, "Invalid mode of year group!")

    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:id>/')
@bp.input(ExaminationScheduleSchema)
@bp.output(MessageSchema)
def update_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_for_enrollment_students'] > data['end_date_for_enrollment_students']:
        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(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