fix error in gitignore

apps/pricing/__init__.py

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+# pricing app

apps/pricing/apps.py

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+from django.apps import AppConfig
+
+
+class PricingConfig(AppConfig):
+    default_auto_field = "django.db.models.BigAutoField"
+    name = "apps.pricing"

apps/pricing/engine.py

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+"""Backend-authoritative pricing engine.
+
+Produces a full, explainable breakdown and is always the source of truth —
+the frontend may display estimates but must never be trusted for financial
+values.
+"""
+from decimal import Decimal, ROUND_HALF_UP
+
+CHARGE_TYPES = {"fixed", "per_kg", "per_unit", "percentage", "tiered", "fee"}
+
+
+class PricingEngine:
+    def calculate(self, weight_kg, selected_steps, currency: str = "IRR") -> dict:
+        weight = Decimal(str(weight_kg))
+        lines = []
+        subtotal = Decimal("0")
+
+        # Pass 1 — charge rules.
+        for step in selected_steps:
+            for rule in step.pricing_rules.filter(active=True, rule_type__in=CHARGE_TYPES).order_by("priority"):
+                line = self._apply_charge_rule(rule, weight)
+                if line is None:
+                    continue
+                lines.append(line)
+                subtotal += Decimal(line["amount"])
+
+        # Pass 2 — discounts (fixed or percentage of subtotal).
+        discounts = Decimal("0")
+        for step in selected_steps:
+            for rule in step.pricing_rules.filter(active=True, rule_type="discount"):
+                amt = Decimal(str(rule.amount))
+                if (rule.config or {}).get("percentage"):
+                    amt = subtotal * amt / Decimal("100")
+                discounts += amt
+                lines.append(
+                    self._line(rule, weight, "discount", Decimal("0"), amt)
+                )
+
+        # Pass 3 — taxes on (subtotal - discounts).
+        taxes = Decimal("0")
+        taxable = subtotal - discounts
+        for step in selected_steps:
+            for rule in step.pricing_rules.filter(active=True, rule_type="tax"):
+                amt = taxable * Decimal(str(rule.amount)) / Decimal("100")
+                taxes += amt
+                lines.append(self._line(rule, weight, "tax", Decimal("0"), amt))
+
+        total = subtotal - discounts + taxes
+        if total < 0:
+            total = Decimal("0")
+
+        return {
+            "currency": currency,
+            "lines": lines,
+            "subtotal": str(self._q(subtotal)),
+            "discounts": str(self._q(discounts)),
+            "taxes": str(self._q(taxes)),
+            "total": str(self._q(total)),
+        }
+
+    def _q(self, v: Decimal) -> Decimal:
+        return v.quantize(Decimal("0.01"), rounding=ROUND_HALF_UP)
+
+    def _line(self, rule, weight, kind, unit_price, amount, quantity=None) -> dict:
+        return {
+            "step_key": rule.step.key,
+            "rule": rule.name,
+            "kind": kind,
+            "quantity": str(quantity if quantity is not None else weight),
+            "unit_price": str(self._q(unit_price)),
+            "amount": str(self._q(amount)),
+        }
+
+    def _apply_charge_rule(self, rule, weight):
+        kind = rule.rule_type
+        cfg = rule.config or {}
+        amount = Decimal(str(rule.amount))
+        unit_price = Decimal("0")
+        quantity = weight
+        if kind == "fixed":
+            unit_price = amount
+        elif kind == "per_kg":
+            unit_price = amount
+            amount = amount * weight
+        elif kind == "per_unit":
+            units = Decimal(str(cfg.get("units", 1)))
+            unit_price = amount
+            amount = amount * units
+            quantity = units
+        elif kind == "percentage":
+            base = Decimal(str(cfg.get("base", 0)))
+            unit_price = amount
+            amount = base * amount / Decimal("100")
+        elif kind == "tiered":
+            unit_price = self._tier_unit_price(cfg.get("tiers", []), weight)
+            amount = unit_price * weight
+        elif kind == "fee":
+            unit_price = Decimal("0")
+        else:
+            return None
+
+        min_c = cfg.get("min_charge")
+        max_c = cfg.get("max_charge")
+        if min_c is not None and amount < Decimal(str(min_c)):
+            amount = Decimal(str(min_c))
+        if max_c is not None and amount > Decimal(str(max_c)):
+            amount = Decimal(str(max_c))
+
+        return self._line(rule, weight, kind, unit_price, amount, quantity)
+
+    def _tier_unit_price(self, tiers, weight) -> Decimal:
+        best = Decimal("0")
+        for tier in tiers or []:
+            low = Decimal(str(tier.get("from", 0)))
+            if weight >= low:
+                best = Decimal(str(tier.get("price", 0)))
+        return best

apps/pricing/migrations/0001_initial.py

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+# Generated by Django 5.2.17 on 2026-09-15 09:29
+
+import django.db.models.deletion
+import uuid
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+        ('workflows', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='PricingRule',
+            fields=[
+                ('id', models.UUIDField(default=uuid.uuid4, editable=False, primary_key=True, serialize=False)),
+                ('created_at', models.DateTimeField(auto_now_add=True, db_index=True)),
+                ('updated_at', models.DateTimeField(auto_now=True)),
+                ('name', models.CharField(max_length=200)),
+                ('rule_type', models.CharField(choices=[('fixed', 'Fixed'), ('per_kg', 'Per kilogram'), ('per_unit', 'Per unit'), ('percentage', 'Percentage'), ('tiered', 'Tiered'), ('discount', 'Discount'), ('tax', 'Tax'), ('fee', 'Additional fee')], max_length=16)),
+                ('amount', models.DecimalField(decimal_places=2, default=0, max_digits=18)),
+                ('config', models.JSONField(blank=True, default=dict)),
+                ('active', models.BooleanField(default=True)),
+                ('priority', models.IntegerField(default=0)),
+                ('step', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='pricing_rules', to='workflows.workflowstep')),
+            ],
+            options={
+                'ordering': ['priority'],
+            },
+        ),
+    ]

apps/pricing/models.py

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+from django.db import models
+
+from apps.core.models import TimeStampedModel, UUIDModel
+
+
+class PricingRule(UUIDModel, TimeStampedModel):
+    class RuleType(models.TextChoices):
+        FIXED = "fixed", "Fixed"
+        PER_KG = "per_kg", "Per kilogram"
+        PER_UNIT = "per_unit", "Per unit"
+        PERCENTAGE = "percentage", "Percentage"
+        TIERED = "tiered", "Tiered"
+        DISCOUNT = "discount", "Discount"
+        TAX = "tax", "Tax"
+        FEE = "fee", "Additional fee"
+
+    step = models.ForeignKey(
+        "workflows.WorkflowStep", on_delete=models.CASCADE, related_name="pricing_rules"
+    )
+    name = models.CharField(max_length=200)
+    rule_type = models.CharField(max_length=16, choices=RuleType.choices)
+    # Base amount. Meaning depends on rule_type:
+    #   fixed/per_kg/per_unit -> money; percentage/discount/tax -> percent.
+    amount = models.DecimalField(max_digits=18, decimal_places=2, default=0)
+    config = models.JSONField(default=dict, blank=True)
+    active = models.BooleanField(default=True)
+    priority = models.IntegerField(default=0)
+
+    class Meta:
+        ordering = ["priority"]
+
+    def __str__(self) -> str:
+        return f"{self.name} ({self.rule_type})"

apps/pricing/tests.py

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+from decimal import Decimal
+
+from django.test import TestCase
+
+from apps.pricing.engine import PricingEngine
+from apps.pricing.models import PricingRule
+from apps.workflows.models import Workflow, WorkflowStep, WorkflowVersion
+
+
+class PricingEngineTests(TestCase):
+    def setUp(self):
+        wf = Workflow.objects.create(name="P", slug="p")
+        self.version = WorkflowVersion.objects.create(workflow=wf, version=1)
+        self.washing = WorkflowStep.objects.create(version=self.version, key="washing", name="Washing")
+        self.drying = WorkflowStep.objects.create(version=self.version, key="drying", name="Drying")
+
+    def test_per_kg(self):
+        PricingRule.objects.create(step=self.washing, name="Wash", rule_type="per_kg", amount=Decimal("5000"))
+        result = PricingEngine().calculate(850, [self.washing])
+        self.assertEqual(result["total"], "4250000.00")
+
+    def test_tiered(self):
+        PricingRule.objects.create(step=self.washing, name="Tiered", rule_type="tiered", config={
+            "tiers": [{"from": 0, "price": "5000"}, {"from": 100, "price": "4000"}, {"from": 500, "price": "3000"}],
+        })
+        result = PricingEngine().calculate(600, [self.washing])
+        self.assertEqual(result["total"], "1800000.00")
+
+    def test_discount_and_tax(self):
+        PricingRule.objects.create(step=self.washing, name="Wash", rule_type="per_kg", amount=Decimal("1000"))
+        PricingRule.objects.create(step=self.washing, name="Disc", rule_type="discount", amount=Decimal("10"), config={"percentage": True})
+        PricingRule.objects.create(step=self.washing, name="Tax", rule_type="tax", amount=Decimal("9"))
+        result = PricingEngine().calculate(100, [self.washing])
+        # subtotal 100000, discount 10% => 10000, taxable 90000, tax 9% => 8100, total 98100
+        self.assertEqual(result["total"], "98100.00")
+
+    def test_multiple_steps(self):
+        PricingRule.objects.create(step=self.washing, name="Wash", rule_type="per_kg", amount=Decimal("5000"))
+        PricingRule.objects.create(step=self.drying, name="Dry", rule_type="per_kg", amount=Decimal("8000"))
+        result = PricingEngine().calculate(100, [self.washing, self.drying])
+        self.assertEqual(result["total"], "1300000.00")