from classifier import  get_pipe
from storage import db_session, MailThread

def predict_threads():
    """
    Predicts the language, topic and if a thread is anwered and writes that to the database. This function doesn't have a return value.
    """
    # Loading pipes for the prediction of each thread
    pipe1,le=get_pipe("pipe1",key=b"answered",filter=["db"])
    pipe2,le2=get_pipe("pipe2g", b"maintopic",["db"])
    pipe3,le3=get_pipe("pipe2b", b"lang",["db"])

    # Loading untrained MailThreads:
    q=db_session.query(MailThread).filter(MailThread.istrained.op("IS NOT")(True))
    mail_threads=q.all()
    
    if len(mail_threads) ==0:
        raise StandardError("no untrained threads found in database")
    
    answered=le.inverse_transform(pipe1.predict(mail_threads))
    maintopic=le2.inverse_transform(pipe2.predict(mail_threads))
    lang=le3.inverse_transform(pipe3.predict(mail_threads))

    for i, t in enumerate(mail_threads):
        t.answered, t.opened, t.maintopic, t.lang = ( bool(answered[i]),
                                                      bool(answered[i]),
                                                      str(maintopic[i]),
                                                      str(lang[i])
        )
        db_session.add(t)
        db_session.commit()