import datetime

from apiflask import APIBlueprint
from flask import abort, current_app
from sqlalchemy import or_, and_
from flask_sqlalchemy import get_debug_queries

from ..schemas import MessageSchema, TermOfDefenceSchema, TermOfDefenceListSchema, \
    TemporaryAvailabilityListSchema, AssignedGroupToTermOfDefenceListSchema, GroupIdSchema
from ...examination_schedule.models import TermOfDefence, TemporaryAvailability, committee
from ...students.models import YearGroup
from ...project_supervisor.models import ProjectSupervisor
from ...dependencies import db
from ..utils import generate_range_dates
from ..query.enrollments import get_term_of_defence_by_id_and_examination_schedule_id, set_new_group_to_term_of_defence, \
    get_examination_schedule_by_id

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


@bp.post('/<int:examination_schedule_id>/generate')
@bp.output(MessageSchema)
def generate_term_of_defence_for_this_examination_schedule(examination_schedule_id: int) -> dict:
    ex = get_examination_schedule_by_id(examination_schedule_id)
    limit = current_app.config.get('LIMIT_MEMBERS_PER_COMMITTEE', 3)

    term_of_defences = TermOfDefence.query. \
        filter(TermOfDefence.examination_schedule_id == examination_schedule_id).first()
    if term_of_defences is not None:
        abort(400,
              "First you have to delete all term of defences for this examination schedule to generate them again!")

    temporary_availabilities = TemporaryAvailability.query. \
        filter(TemporaryAvailability.examination_schedule_id == examination_schedule_id). \
        join(TemporaryAvailability.project_supervisor). \
        all()
    if len(temporary_availabilities) == 0:
        abort(404, "Not found temporary availabilities for project supervisors")

    dates = generate_range_dates(ex.start_date, ex.end_date, ex.duration_time)

    term_of_defences = []
    for d in dates:
        e = d + datetime.timedelta(minutes=ex.duration_time)
        t = list(filter(lambda ta: ta.start_date <= d and ta.end_date >= e, temporary_availabilities))
        if len(t) >= limit:
            projects_supervisors = [t[i].project_supervisor for i in range(limit)]
            term_of_defence = TermOfDefence(start_date=d, end_date=e, examination_schedule_id=examination_schedule_id)
            term_of_defence.members_of_committee = projects_supervisors
            term_of_defences.append(term_of_defence)
    db.session.add_all(term_of_defences)
    db.session.commit()
    return {"message": "Term of defences was generated!"}


@bp.post('/<int:examination_schedule_id>/clear-term-of-defences/')
@bp.output(MessageSchema)
def clear_generated_term_of_defences(examination_schedule_id: int) -> dict:
    get_examination_schedule_by_id(examination_schedule_id)

    # count_defences = db.func.count(ProjectSupervisor.id)
    # td = db.session.query(TermOfDefence, count_defences). \
    #     join(ProjectSupervisor, isouter=True). \
    #     filter(TermOfDefence.examination_schedule_id == examination_schedule_id). \
    #     group_by(TermOfDefence.id).having(count_defences > 0).first()
    # print(td)
    # if td is not None:
    #     abort(400, "First you remove group assigned to term of defence to clear term of defences!")

    td = TermOfDefence.query. \
        filter(TermOfDefence.examination_schedule_id == examination_schedule_id).all()
    while True:
        for t in td[0:10]:
            db.session.delete(t)
        db.session.commit()
        if len(td) == 0:
            break
        td[0:10] = []
    # print(len(get_debug_queries()))
    return {"message": "Term of defences was deleted!"}


@bp.post('/<int:examination_schedule_id>/add')
@bp.input(TermOfDefenceSchema)
@bp.output(MessageSchema)
def create_term_of_defence(examination_schedule_id: int, data: dict) -> dict:
    if not data:
        abort(400, "You have passed empty data!")

    ex = get_examination_schedule_by_id(examination_schedule_id)

    yg_id = ex.year_group_id
    project_supervisors_ids = data.pop('project_supervisors')
    project_supervisors = ProjectSupervisor.query.filter(
        or_(*[ProjectSupervisor.id == i for i in project_supervisors_ids])).filter(YearGroup.id == yg_id).all()

    if len(project_supervisors) != len(project_supervisors_ids):
        abort(404, "Project Supervisors didn't exist!")

    start_date = data['start_date']
    end_date = data['end_date']

    if not (ex.start_date.timestamp() <= start_date.timestamp() and ex.end_date.timestamp() >= end_date.timestamp()):
        abort(400, "Invalid date range!")

    if end_date <= start_date:
        abort(400, "End date must be greater than start date!")

    delta_time = end_date - start_date
    delta_time_in_minutes = delta_time.total_seconds() / 60
    if delta_time_in_minutes != ex.duration_time:
        abort(400, "Invalid duration time!")

    td = TermOfDefence.query.filter(TermOfDefence.examination_schedule_id == examination_schedule_id). \
        filter(
        or_(and_(TermOfDefence.start_date >= start_date,
                 TermOfDefence.start_date < end_date,
                 TermOfDefence.end_date >= end_date),
            and_(TermOfDefence.start_date <= start_date,
                 TermOfDefence.end_date > start_date,
                 TermOfDefence.end_date <= end_date))).first()

    if td is not None:
        abort(400, "This term of defence is taken! You choose other date!")

    td = TermOfDefence(**data, examination_schedule_id=examination_schedule_id)
    db.session.add(td)
    db.session.commit()
    for p in project_supervisors:
        td.members_of_committee.append(p)
    db.session.commit()
    return {"message": "Term of defence was created!"}


@bp.put('/<int:examination_schedule_id>/update/<int:term_of_defence_id>/')
@bp.input(TermOfDefenceSchema)
@bp.output(MessageSchema)
def update_term_of_defence(examination_schedule_id: int, term_of_defence_id: int, data: dict) -> dict:
    if not data:
        abort(400, "You have passed empty data!")

    td_query = TermOfDefence.query.filter(TermOfDefence.id == term_of_defence_id,
                                          TermOfDefence.examination_schedule_id == examination_schedule_id)
    td = td_query.first()
    if td is None:
        abort(404, "Not found term of defence!")

    ex = td.examination_schedule
    yg_id = ex.year_group_id
    project_supervisors_ids = data.pop('project_supervisors')
    project_supervisors = ProjectSupervisor.query.filter(
        or_(*[ProjectSupervisor.id == i for i in project_supervisors_ids])).filter(YearGroup.id == yg_id).all()

    if len(project_supervisors) != len(project_supervisors_ids):
        abort(404, "Project Supervisors didn't exist!")

    start_date = data['start_date']
    end_date = data['end_date']
    if not (ex.start_date.timestamp() <= start_date.timestamp() and ex.end_date.timestamp() >= end_date.timestamp()):
        abort(400, "Invalid date range!")

    if end_date <= start_date:
        abort(400, "End date must be greater than start date!")

    delta_time = end_date - start_date
    delta_time_in_minutes = delta_time.total_seconds() / 60
    if delta_time_in_minutes != ex.duration_time:
        abort(400, "Invalid duration time!")

    term_of_defence = TermOfDefence.query.filter(TermOfDefence.id != term_of_defence_id,
                                                 TermOfDefence.examination_schedule_id == examination_schedule_id). \
        filter(
        or_(and_(TermOfDefence.start_date >= start_date,
                 TermOfDefence.start_date < end_date,
                 TermOfDefence.end_date >= end_date),
            and_(TermOfDefence.start_date <= start_date,
                 TermOfDefence.end_date > start_date,
                 TermOfDefence.end_date <= end_date))).first()

    if term_of_defence is not None:
        abort(400, "This term of defence is taken! You choose other date!")

    td_query.update(data)
    td.members_of_committee = []
    db.session.commit()
    for p in project_supervisors:
        td.members_of_committee.append(p)
    db.session.commit()

    return {"message": "Term of defence was updated!"}


@bp.delete('/<int:examination_schedule_id>/delete/<int:term_of_defence_id>/')
@bp.output(MessageSchema)
def delete_term_of_defence(examination_schedule_id: int, term_of_defence_id: int) -> dict:
    td = get_term_of_defence_by_id_and_examination_schedule_id(examination_schedule_id, term_of_defence_id)
    db.session.delete(td)
    db.session.commit()
    return {"message": "Term of defence was deleted!"}


@bp.get('/<int:examination_schedule_id>/term-of-defences/')
@bp.output(TermOfDefenceListSchema)
def list_of_term_of_defences(examination_schedule_id: int) -> dict:
    get_examination_schedule_by_id(examination_schedule_id)

    td = TermOfDefence.query. \
        filter(TermOfDefence.examination_schedule_id == examination_schedule_id). \
        join(TermOfDefence.members_of_committee, isouter=True). \
        all()
    return {"term_of_defences": td}


@bp.get('/<int:examination_schedule_id>/temporary-availabilities/')
@bp.output(TemporaryAvailabilityListSchema)
def list_of_temporary_availability(examination_schedule_id: int) -> dict:
    get_examination_schedule_by_id(examination_schedule_id)

    td = TemporaryAvailability.query. \
        filter(TemporaryAvailability.examination_schedule_id == examination_schedule_id). \
        join(TemporaryAvailability.project_supervisor). \
        all()
    return {"temporary_availabilities": td}


@bp.get('/<int:examination_schedule_id>/assigned-group-to-term-of-defences/')
@bp.output(AssignedGroupToTermOfDefenceListSchema)
def list_of_assigned_group_to_term_of_defences(examination_schedule_id: int) -> dict:
    get_examination_schedule_by_id(examination_schedule_id)

    td = TermOfDefence.query. \
        join(TermOfDefence.members_of_committee, isouter=True). \
        join(TermOfDefence.group). \
        filter(TermOfDefence.examination_schedule_id == examination_schedule_id). \
        filter(TermOfDefence.group_id.isnot(None)). \
        all()
    return {"term_of_defences": td}


@bp.post('/<int:examination_schedule_id>/term-of-defence/<int:term_of_defence_id>/group/')
@bp.input(GroupIdSchema)
@bp.output(MessageSchema)
def add_group_to_term_of_defence(examination_schedule_id: int, term_of_defence_id: int, data: dict) -> dict:
    set_new_group_to_term_of_defence(examination_schedule_id, term_of_defence_id, data.get("group_id"))
    db.session.commit()
    return {"message": "Group was added to term of defences!"}


@bp.delete('/<int:examination_schedule_id>/term-of-defence/<int:term_of_defence_id>/group/')
@bp.output(MessageSchema)
def delete_group_to_term_of_defence(examination_schedule_id: int, term_of_defence_id: int) -> dict:
    td = get_term_of_defence_by_id_and_examination_schedule_id(examination_schedule_id, term_of_defence_id)
    td.group_id = None
    db.session.commit()
    return {"message": "Group was deleted from term of defences!"}


@bp.put('/<int:examination_schedule_id>/term-of-defence/<int:term_of_defence_id>/group/')
@bp.input(GroupIdSchema)
@bp.output(MessageSchema)
def update_group_for_term_of_defence(examination_schedule_id: int, term_of_defence_id: int, data: dict) -> dict:
    set_new_group_to_term_of_defence(examination_schedule_id, term_of_defence_id, data.get("group_id"))
    db.session.commit()
    return {"message": "Group for term of defence was updated!"}