from sqlalchemy import func
from scores.model.score_model import Score
from students.model.students_model import Students
from class_management.model.class_management_model import ClassInfo

def get_top_students_dao(db):
    top_sids = (db.query(Score.sid)
        .filter(Score.is_deleted == 0)
        .group_by(Score.sid, Score.num)
        .having(func.min(Score.score) >= 80)
        .subquery() )

    results = (db.query(Students.id,
            Students.name,
            Score.num,
            Score.t_subject,
            Score.score,)
        .join(Score, Students.id == Score.sid)
        .filter( Score.sid.in_(top_sids),
            Score.is_deleted == 0,)
        .order_by(Students.id, Score.num)
        .all())

    return [{"sid": r.sid,
            "name": r.name,
            "score": r.score,}
        for r in results]


def get_failing_students_dao(db):
    failing_sids = (db.query(Score.sid)
        .filter(Score.score < 60,
            Score.is_deleted == 0,)
        .group_by(Score.sid)
        .having(func.count() >= 2)
        .subquery())

    results = (db.query(
            Students.id,
            Students.name,
            ClassInfo.name.label("class_name"),
            Score.num,
            Score.t_subject,
            Score.score,)
        .join(Score, Students.id == Score.sid)
        .join(ClassInfo, Score.cid == ClassInfo.id)
        .filter(Score.sid.in_(failing_sids),
            Score.score < 60,
            Score.is_deleted == 0,)
        .order_by(ClassInfo.id, Score.num)
        .all())

    return [{"sid": r.sid,
            "name": r.name,
            "class_name": r.class_name,
            "num": r.num,
            "t_subject": r.tsub,
            "score": r.score,}
        for r in results]



def get_class_avg_dao(db):
    results = (db.query(Score.num,
            Score.cid,
            ClassInfo.name.label("class_name"),
            func.avg(Score.score).label("avg_score"))
        .join(ClassInfo, Score.cid == ClassInfo.id)
        .filter(Score.is_deleted == 0)
        .group_by(Score.num, Score.cid, ClassInfo.name)
        .order_by(func.avg(Score.score).desc())
        .all())

    return [ {"num": r.num,
            "cid": r.cid,
            "class_name": r.class_name,
            "avg_score": round(float(r.avg_score), 2),}
        for r in results]