from django.db.models.signals import post_save

from django.dispatch import receiver



from jobs.models import JobApplication

from seekers.models import SeekerProfile



from .models import ApplicationEvent

from .services import log_event, process_application_scoring, reprocess_applications_for_user



_SCORING_ONLY_FIELDS = frozenset({

    'match_score', 'cv_parsed_text', 'cv_extracted_skills', 'cv_parsed_at', 'updated_at',

})

_SKIP_RESCORE_FIELDS = _SCORING_ONLY_FIELDS | {'status', 'rating'}

_PROFILE_CONTENT_FIELDS = frozenset({

    'skills', 'bio', 'education', 'experience_summary', 'qualification', 'headline', 'cv_file',

})





@receiver(post_save, sender=JobApplication)

def on_application_saved(sender, instance, created, **kwargs):

    update_fields = kwargs.get('update_fields')

    if update_fields and set(update_fields).issubset(_SKIP_RESCORE_FIELDS):

        if created:

            log_event(

                instance,

                instance.applicant,

                ApplicationEvent.EventType.CREATED,

                message='Application submitted',

            )

        return



    process_application_scoring(instance, parse_content=True)



    if created:

        message = 'Application submitted'

        if instance.cv_parsed_text:

            skill_count = len(instance.cv_skill_list)

            message = f'Application submitted - profile/CV analyzed ({skill_count} skill(s) detected)'

        log_event(

            instance,

            instance.applicant,

            ApplicationEvent.EventType.CREATED,

            message=message,

        )





@receiver(post_save, sender=SeekerProfile)

def on_seeker_profile_updated(sender, instance, **kwargs):

    if not instance.user_id:

        return



    update_fields = kwargs.get('update_fields')

    if update_fields and not set(update_fields) & _PROFILE_CONTENT_FIELDS:

        return



    reprocess_applications_for_user(instance.user)