from django.conf import settings
from django.db import migrations, models

import base36
import random

def random_code():
    return base36.dumps(
        random.randint(pow(36, code_length - 2), pow(36, code_length - 1) - 1)
    )

# Migrate existing GroupedOrder `place` to the new `place` table
def link_existing_place(apps, schema_editor):
    GroupedOrder = apps.get_model('order', 'GroupedOrder')
    Place = apps.get_model('order', 'Place')
    for grouped_order in GroupedOrder.objects.all():
        if grouped_order.place:
            # Generate new random code for this existing place
            code = random_code()
            while Place.objects.all().filter(code=code):
                # Random code already exists, try a new random code
                code = random_code()

            place = Place.objects.create(
                name=grouped_order.place,
                code=code,
            )

            grouped_order.places.add(place)
            grouped_order.save()

class Migration(migrations.Migration):
    dependencies = [
        ("order", "0029_set_phone_mandatory_for_existing_orders"),
    ]

    operations = [
        migrations.CreateModel(
            name="Place",
            fields=[
                (
                    "id",
                    models.BigAutoField(
                        auto_created=True,
                        primary_key=True,
                        serialize=False,
                        verbose_name="ID",
                    ),
                ),
                ("name", models.CharField(max_length=100, verbose_name="Nom du lieu de distribution")),
                ("code", models.CharField(max_length=20, verbose_name="Identifiant unique du lieu (raccourci)", unique=True)),
                ("orga", models.ForeignKey(on_delete=models.deletion.CASCADE, to=settings.AUTH_USER_MODEL, verbose_name='Organisateur·ice')),
                ("description", models.TextField(blank=True, null=True, verbose_name="Description")),
            ],
        ),
        migrations.AddField(
            model_name="groupedorder",
            name="places",
            field=models.ManyToManyField(
                to="order.place",
                verbose_name="Lieux de distribution",
                related_name="orders",
            )
        ),
        migrations.RunPython(link_existing_place),
        migrations.RemoveField(
            model_name='groupedorder',
            name='place',
        ),
        migrations.AddField(
            model_name="order",
            name="place",
            field=models.ForeignKey(blank=True, null=True, on_delete=models.deletion.CASCADE, to='order.place'),
        ),
        migrations.AddIndex(
            model_name="groupedorder",
            index=models.Index(fields=["code"], name="order_group_code_50902d_idx"),
        ),
        migrations.AddIndex(
            model_name="place",
            index=models.Index(fields=["code"], name="order_place_code_4e2b27_idx"),
        ),
    ]