@@ -0,0 +1,230 @@
+import re
+from datetime import datetime
+from decimal import Decimal, InvalidOperation
+from pathlib import Path
+from typing import Any, NamedTuple
+
+from django.core.management.base import BaseCommand, CommandError
+from django.db.migrations.loader import MigrationLoader
+
+from ml_model.models import NeuronModel
+from payments.models import PaymentPlanFeature
+
+MEASUREMENT_UNITS = {choice.value for choice in PaymentPlanFeature.MeasurementUnitChoices}
+PAYMENTS_APP_LABEL = 'payments'
+
+
+def _sanitize_slug(slug: str) -> str:
+    return re.sub(r'[^a-zA-Z0-9_]', '_', slug)
+
+
+class PaymentsMigrationSlot(NamedTuple):
+    """dependency — лист графа для dependencies; next_number — префикс нового файла."""
+
+    dependency: str
+    next_number: int
+
+
+def _resolve_payments_migration_slot() -> PaymentsMigrationSlot:
+    """Один проход MigrationLoader: хвост ветки и номер следующей миграции."""
+    loader = MigrationLoader(None, ignore_no_migrations=True)
+
+    leaves = sorted(name for app, name in loader.graph.leaf_nodes() if app == PAYMENTS_APP_LABEL)
+    if not leaves:
+        raise CommandError(f'В приложении {PAYMENTS_APP_LABEL} нет миграций.')
+    if len(leaves) > 1:
+        raise CommandError(
+            f'У {PAYMENTS_APP_LABEL} несколько концов веток: {", ".join(leaves)}. '
+            f'Сначала смержите: python manage.py makemigrations {PAYMENTS_APP_LABEL} --merge'
+        )
+
+    dependency = leaves[0]
+    prefix = dependency.split('_', 1)[0]
+    if not prefix.isdigit():
+        raise CommandError(f'Не удалось вычислить номер следующей миграции из листа "{dependency}".')
+    return PaymentsMigrationSlot(dependency=dependency, next_number=int(prefix) + 1)
+
+
+def _migration_basename(model_slug: str, next_number: int) -> str:
+    safe_slug = _sanitize_slug(model_slug)
+    return f'{next_number:04d}_add_{safe_slug}_payment_features'
+
+
+def _build_migration_source(
+    *,
+    func_name: str,
+    model_slug: str,
+    price: Decimal,
+    measurement_unit: str,
+    price_threshold: int,
+    latest_migration: str,
+) -> str:
+    return f"""# Generated by makemigration_payment_features on {datetime.now():%Y-%m-%d %H:%M}
+
+import math
+from decimal import Decimal
+
+from django.db import migrations
+from django.db.models import Max
+
+
+def {func_name}(apps, schema_editor):
+    PaymentPlan = apps.get_model('payments', 'PaymentPlan')
+    PaymentPlanFeature = apps.get_model('payments', 'PaymentPlanFeature')
+    NeuronModel = apps.get_model('ml_model', 'NeuronModel')
+
+    price = Decimal('{price}')
+    measurement_unit = '{measurement_unit}'
+    price_threshold = {price_threshold}
+    model = NeuronModel.objects.get(slug='{model_slug}')
+    category = model.category
+
+    max_order_by_plan_id = {{
+        row['plan_id']: row['max_order']
+        for row in PaymentPlanFeature.objects.filter(model__category=category)
+        .values('plan_id')
+        .annotate(max_order=Max('order'))
+    }}
+
+    features = []
+    for plan in PaymentPlan.objects.filter(price__gt=price_threshold):
+        quantity = math.floor(plan.tokens_per_plan / price)
+        next_order = (max_order_by_plan_id.get(plan.pk) or -1) + 1
+        max_order_by_plan_id[plan.pk] = next_order
+        features.append(
+            PaymentPlanFeature(
+                plan=plan,
+                model=model,
+                quantity=quantity,
+                measurement_unit=measurement_unit,
+                order=next_order,
+            )
+        )
+    PaymentPlanFeature.objects.bulk_create(
+        features,
+        update_conflicts=True,
+        update_fields=['quantity', 'measurement_unit'],
+        unique_fields=['plan', 'model'],
+    )
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('payments', '{latest_migration}'),
+    ]
+
+    operations = [
+        migrations.RunPython({func_name}, migrations.RunPython.noop),
+    ]
+"""
+
+
+class Command(BaseCommand):
+    help = (
+        'Создаёт data-миграцию payments с PaymentPlanFeature для указанной модели. '
+        'Применение: python manage.py migrate payments'
+    )
+
+    def add_arguments(self, parser):
+        parser.add_argument('modelname', type=str, help='Slug модели (NeuronModel)')
+        parser.add_argument('--price', type=str, help='Цена за единицу измерения (токены)')
+        parser.add_argument(
+            '--measurement-unit',
+            type=str,
+            choices=sorted(MEASUREMENT_UNITS),
+            help='Единица измерения: text_page, file, time',
+        )
+        parser.add_argument(
+            '--price-threshold',
+            type=int,
+            help='Создавать фичи только для планов с price строго больше этого значения',
+        )
+
+    def handle(self, *args: Any, **options: Any) -> None:
+        model_slug = options['modelname'].strip()
+        self._validate_model_name(model_slug)
+        price = self._read_price(options.get('price'))
+        measurement_unit = self._read_measurement_unit(options.get('measurement_unit'))
+        price_threshold = self._read_price_threshold(options.get('price_threshold'))
+
+        self.stdout.write(
+            f'Миграция для model={model_slug}, price={price}, '
+            f'measurement_unit={measurement_unit}, price_threshold={price_threshold}'
+        )
+        self.stdout.write('Расчёт quantity выполнится на стейдже/проде при migrate по планам в БД.')
+
+        slot = _resolve_payments_migration_slot()
+        migration_name = _migration_basename(model_slug, slot.next_number)
+        func_name = f'add_{_sanitize_slug(model_slug)}_payment_features'
+        source = _build_migration_source(
+            func_name=func_name,
+            model_slug=model_slug,
+            price=price,
+            measurement_unit=measurement_unit,
+            price_threshold=price_threshold,
+            latest_migration=slot.dependency,
+        )
+
+        migration_path = (
+            Path(__file__).resolve().parent.parent.parent / 'migrations' / f'{migration_name}.py'
+        )
+        if migration_path.exists():
+            raise CommandError(f'Файл миграции уже существует: {migration_path}')
+
+        migration_path.write_text(source, encoding='utf-8')
+        self.stdout.write(self.style.SUCCESS(f'Создана миграция: {migration_path}'))
+        self.stdout.write('Примените: python manage.py migrate payments')
+
+    def _read_price(self, value: str | None) -> Decimal:
+        if value is not None:
+            try:
+                price = Decimal(value)
+            except InvalidOperation as exc:
+                raise CommandError(f'Некорректная цена: {value}') from exc
+            if price <= 0:
+                raise CommandError('Цена должна быть больше 0.')
+            return price
+
+        while True:
+            raw = input('Введите прайс за единицу измерения (токены): ').strip()
+            try:
+                price = Decimal(raw)
+            except InvalidOperation:
+                self.stderr.write('Введите число.')
+                continue
+            if price <= 0:
+                self.stderr.write('Цена должна быть больше 0.')
+                continue
+            return price
+
+    def _read_measurement_unit(self, value: str | None) -> str:
+        units = ', '.join(sorted(MEASUREMENT_UNITS))
+
+        if value is not None:
+            if value not in MEASUREMENT_UNITS:
+                raise CommandError(f'Недопустимая ед. измерения: {value}. Допустимые: {units}')
+            return value
+
+        while True:
+            raw = input(f'Введите ед. измерения ({units}): ').strip()
+            if raw in MEASUREMENT_UNITS:
+                return raw
+            self.stderr.write(f'Допустимые значения: {units}')
+
+    def _read_price_threshold(self, value: int | None) -> int:
+        if value is not None:
+            return value
+
+        while True:
+            raw = input('Введите планы выше какого price будут учитываться: ').strip()
+            try:
+                return int(raw)
+            except ValueError:
+                self.stderr.write('Введите целое число.')
+
+    def _validate_model_name(self, model_slug: str) -> None:
+        if NeuronModel.objects.filter(slug=model_slug).exists():
+            return
+
+        raise CommandError(f'NeuronModel со slug "{model_slug}" не найдена.')