import django.db.models.deletion
from django.db import migrations, models


def create_materials_for_existing_fertilizers(apps, schema_editor):
    Fertilizer = apps.get_model('fertilizer', 'Fertilizer')
    Material = apps.get_model('materials', 'Material')
    FertilizerProfile = apps.get_model('materials', 'FertilizerProfile')

    for fertilizer in Fertilizer.objects.all():
        material = Material.objects.create(
            name=fertilizer.name,
            material_type='fertilizer',
            maker=fertilizer.maker or '',
            stock_unit='bag',
            is_active=True,
            notes=fertilizer.notes or '',
        )
        FertilizerProfile.objects.create(
            material=material,
            capacity_kg=fertilizer.capacity_kg,
            nitrogen_pct=fertilizer.nitrogen_pct,
            phosphorus_pct=fertilizer.phosphorus_pct,
            potassium_pct=fertilizer.potassium_pct,
        )
        fertilizer.material = material
        fertilizer.save(update_fields=['material'])


def reverse_migration(apps, schema_editor):
    Fertilizer = apps.get_model('fertilizer', 'Fertilizer')
    Fertilizer.objects.all().update(material=None)


class Migration(migrations.Migration):

    dependencies = [
        ('fertilizer', '0004_fertilizationplan_calc_settings'),
        ('materials', '0001_initial'),
    ]

    operations = [
        migrations.AddField(
            model_name='fertilizer',
            name='material',
            field=models.OneToOneField(
                blank=True,
                null=True,
                on_delete=django.db.models.deletion.SET_NULL,
                related_name='legacy_fertilizer',
                to='materials.material',
                verbose_name='資材マスタ',
            ),
        ),
        migrations.RunPython(create_materials_for_existing_fertilizers, reverse_migration),
    ]