import os
import sys
import django

# Set up Django
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "config.settings")
django.setup()

from core.models import Voter, ScheduledCall
from django.db.models.signals import pre_save, post_save, post_delete
from django.dispatch import receiver

# New pre_save signal
def handle_voter_status_on_voted_pre_save(sender, instance, **kwargs):
    if instance.voted:
        instance.target_door_visit = False
        instance.call_queue_status = 'no_call_required'

# I will append this to the file instead of monkey patching if possible,
# but for now I'll just write the whole signal part.

# Let's read models.py and replace the signals with better ones.
with open('core/models.py', 'r') as f:
    content = f.read()

# 1. Add pre_save signal before the other signals
new_pre_save = """
@receiver(pre_save, sender=Voter)
def handle_voter_status_on_voted_pre_save(sender, instance, **kwargs):
    \"\"\"
    If a voter has voted, ensure they are not targets for door visits or calls.
    \"\"\"
    if instance.voted:
        instance.target_door_visit = False
        instance.call_queue_status = 'no_call_required'
"""

if '@receiver(pre_save, sender=Voter)' not in content:
    # Insert before the first post_save
    content = content.replace('@receiver(post_save, sender=Voter)', new_pre_save + '\n@receiver(post_save, sender=Voter)', 1)

# 2. Update update_voter_call_queue_status_on_voter_save
import re

old_call_signal = re.search(r'def update_voter_call_queue_status_on_voter_save\(sender, instance, \*\*kwargs\):.*?return', content, re.DOTALL)
# Actually, it's better to just replace the whole function content.

new_call_signal_body = """def update_voter_call_queue_status_on_voter_save(sender, instance, **kwargs):
    \"\"\"
    Sync call_queue_status when is_targeted, candidate_support or voted changes.
    \"\"\"
    if getattr(instance, '_skip_signals', False):
        return

    orig = getattr(instance, '_orig_obj', None)
    if orig and instance.call_queue_status != orig.call_queue_status:
        # If call_queue_status was manually changed, don't auto-override in this save
        return

    update_fields = kwargs.get('update_fields')
    if update_fields:
        relevant = {'is_targeted', 'candidate_support', 'voted'}
        if not relevant.intersection(update_fields):
            return

    # PRIORITY 1: If they voted, no call required and cancel pending calls
    if instance.voted:
        # Cancel any pending calls
        ScheduledCall.objects.filter(voter=instance, status='pending').update(status='cancelled')
        
        if instance.call_queue_status != 'no_call_required':
            Voter.objects.filter(pk=instance.pk).update(call_queue_status='no_call_required')
        return

    # PRIORITY 2: Check if in queue (pending scheduled call)
    if ScheduledCall.objects.filter(voter=instance, status='pending').exists():
        if instance.call_queue_status != 'in_call_queue':
            Voter.objects.filter(pk=instance.pk).update(call_queue_status='in_call_queue')
        return

    # PRIORITY 3: If support is 'supporting', then 'no_call_required'
    if instance.candidate_support == 'supporting':
        if instance.call_queue_status != 'no_call_required':
            Voter.objects.filter(pk=instance.pk).update(call_queue_status='no_call_required')
        return

    # PRIORITY 4: If un-targeted, set to no_call_required
    if not instance.is_targeted:
        if instance.call_queue_status != 'no_call_required':
            Voter.objects.filter(pk=instance.pk).update(call_queue_status='no_call_required')
    else:
        # If targeted, and currently no_call_required, set to to_be_called
        if instance.call_queue_status == 'no_call_required':
             Voter.objects.filter(pk=instance.pk).update(call_queue_status='to_be_called')"""

# Use regex to replace the function
content = re.sub(r'def update_voter_call_queue_status_on_voter_save\(sender, instance, \*\*kwargs\):.*?# PRIORITY 3: If targeted, and currently no_call_required, set to to_be_called.*?Voter.objects.filter\(pk=instance.pk\).update\(call_queue_status=\'to_be_called\'\)', new_call_signal_body, content, flags=re.DOTALL)

# 3. Update update_voter_call_queue_status_on_call_save to check voted
new_call_save_body = """def update_voter_call_queue_status_on_call_save(sender, instance, **kwargs):
    \"\"\"
    Sync Voter.call_queue_status when a ScheduledCall is saved.
    \"\"\"
    voter = instance.voter
    
    # PRIORITY 0: If they voted, always no_call_required
    if voter.voted:
        if voter.call_queue_status != 'no_call_required':
            voter.call_queue_status = 'no_call_required'
            voter.save(update_fields=['call_queue_status'])
        return"""

content = content.replace('def update_voter_call_queue_status_on_call_save(sender, instance, **kwargs):\n    \"\"\"\n    Sync Voter.call_queue_status when a ScheduledCall is saved.\n    \"\"\"\n    voter = instance.voter', new_call_save_body)

with open('core/models.py', 'w') as f:
    f.write(content)

print("Updated core/models.py with more robust signals.")