"""
Contract test for POST /subscriptions endpoint.
This test MUST fail before implementation.
"""

import pytest
from django.test import TestCase
from django.urls import reverse
from rest_framework.test import APIClient
from rest_framework import status
import json


class SubscriptionsPostContractTest(TestCase):
    def setUp(self):
        self.client = APIClient()
        self.subscriptions_url = '/api/v1/subscriptions/'

        # Admin authentication header
        self.admin_auth = {'HTTP_AUTHORIZATION': 'Bearer admin_token'}

        # Tenant admin authentication header
        self.tenant_admin_auth = {'HTTP_AUTHORIZATION': 'Bearer tenant_admin_token'}

        # Valid subscription data
        self.subscription_data = {
            'tenant_id': 'test-tenant-id',
            'plan': 'GROWTH',
            'pricing_model': 'SUBSCRIPTION',
            'billing_cycle': 'MONTHLY',
            'payment_method': {
                'type': 'CARD',
                'card_last4': '4242',
                'expiry_month': 12,
                'expiry_year': 2025,
                'brand': 'visa'
            },
            'modules': ['retail', 'inventory'],
            'trial_days': 14,
            'notes': 'Subscription for retail business'
        }

    def test_create_subscription_success_admin(self):
        """Test successful subscription creation by admin."""
        response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(self.subscription_data),
            content_type='application/json',
            **self.admin_auth
        )

        # This should fail before implementation
        assert response.status_code == status.HTTP_201_CREATED

        data = response.json()
        assert 'id' in data
        assert data['tenant_id'] == self.subscription_data['tenant_id']
        assert data['plan'] == self.subscription_data['plan']
        assert data['pricing_model'] == self.subscription_data['pricing_model']
        assert data['billing_cycle'] == self.subscription_data['billing_cycle']
        assert data['status'] == 'TRIAL'  # Default status with trial_days

        # Should have timestamps
        assert 'created_at' in data
        assert 'updated_at' in data

        # Should have billing period information
        assert 'current_period_start' in data
        assert 'current_period_end' in data
        assert 'trial_end' in data

        # Should include modules
        assert 'modules' in data
        assert data['modules'] == self.subscription_data['modules']

    def test_create_subscription_success_tenant_admin(self):
        """Test successful subscription creation by tenant admin."""
        # Tenant admin creates subscription for their own tenant
        tenant_subscription_data = self.subscription_data.copy()
        del tenant_subscription_data['tenant_id']  # Should be inferred from context

        response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(tenant_subscription_data),
            content_type='application/json',
            **self.tenant_admin_auth
        )

        # This should fail before implementation
        assert response.status_code == status.HTTP_201_CREATED

        data = response.json()
        assert 'id' in data
        assert data['plan'] == tenant_subscription_data['plan']
        assert data['tenant_id']  # Should be auto-populated

    def test_create_subscription_unauthorized(self):
        """Test subscription creation without authentication."""
        response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(self.subscription_data),
            content_type='application/json'
        )

        assert response.status_code == status.HTTP_401_UNAUTHORIZED

    def test_create_subscription_forbidden(self):
        """Test subscription creation by regular user (no permissions)."""
        user_auth = {'HTTP_AUTHORIZATION': 'Bearer user_token'}

        response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(self.subscription_data),
            content_type='application/json',
            **user_auth
        )

        assert response.status_code == status.HTTP_403_FORBIDDEN

    def test_create_subscription_missing_required_fields(self):
        """Test subscription creation with missing required fields."""
        incomplete_data = self.subscription_data.copy()
        del incomplete_data['plan']

        response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(incomplete_data),
            content_type='application/json',
            **self.admin_auth
        )

        assert response.status_code == status.HTTP_400_BAD_REQUEST

        data = response.json()
        assert 'plan' in data.get('errors', {})

    def test_create_subscription_invalid_plan(self):
        """Test subscription creation with invalid plan."""
        invalid_data = self.subscription_data.copy()
        invalid_data['plan'] = 'INVALID_PLAN'

        response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(invalid_data),
            content_type='application/json',
            **self.admin_auth
        )

        assert response.status_code == status.HTTP_400_BAD_REQUEST

    def test_create_subscription_invalid_billing_cycle(self):
        """Test subscription creation with invalid billing cycle."""
        invalid_data = self.subscription_data.copy()
        invalid_data['billing_cycle'] = 'INVALID_CYCLE'

        response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(incomplete_data),
            content_type='application/json',
            **self.admin_auth
        )

        assert response.status_code == status.HTTP_400_BAD_REQUEST

    def test_create_subscription_duplicate_tenant(self):
        """Test subscription creation with duplicate tenant."""
        # First request should succeed (if implemented)
        first_response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(self.subscription_data),
            content_type='application/json',
            **self.admin_auth
        )

        if first_response.status_code == status.HTTP_201_CREATED:
            # Second request with same tenant should fail
            second_response = self.client.post(
                self.subscriptions_url,
                data=json.dumps(self.subscription_data),
                content_type='application/json',
                **self.admin_auth
            )
            assert second_response.status_code == status.HTTP_400_BAD_REQUEST

    def test_create_subscription_without_trial(self):
        """Test subscription creation without trial period."""
        no_trial_data = self.subscription_data.copy()
        del no_trial_data['trial_days']

        response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(no_trial_data),
            content_type='application/json',
            **self.admin_auth
        )

        if response.status_code == status.HTTP_201_CREATED:
            data = response.json()
            # Should be active immediately without trial
            assert data['status'] == 'ACTIVE'
            assert 'trial_end' not in data or data['trial_end'] is None

    def test_create_subscription_with_invalid_modules(self):
        """Test subscription creation with invalid modules."""
        invalid_data = self.subscription_data.copy()
        invalid_data['modules'] = ['invalid_module']

        response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(invalid_data),
            content_type='application/json',
            **self.admin_auth
        )

        assert response.status_code == status.HTTP_400_BAD_REQUEST

    def test_create_subscription_tenant_admin_cross_tenant(self):
        """Test that tenant admin cannot create subscription for other tenant."""
        # Tenant admin trying to create subscription for different tenant
        response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(self.subscription_data),
            content_type='application/json',
            **self.tenant_admin_auth
        )

        # Should fail because tenant_id doesn't match their tenant
        assert response.status_code == status.HTTP_403_FORBIDDEN

    def test_create_subscription_payment_method_validation(self):
        """Test subscription creation with invalid payment method."""
        invalid_data = self.subscription_data.copy()
        invalid_data['payment_method'] = {
            'type': 'CARD',
            'card_last4': '4242',
            # Missing required expiry fields
        }

        response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(invalid_data),
            content_type='application/json',
            **self.admin_auth
        )

        assert response.status_code == status.HTTP_400_BAD_REQUEST

    def test_create_subscription_with_promo_code(self):
        """Test subscription creation with promo code."""
        promo_data = self.subscription_data.copy()
        promo_data['promo_code'] = 'WELCOME20'

        response = self.client.post(
            self.subscriptions_url,
            data=json.dumps(promo_data),
            content_type='application/json',
            **self.admin_auth
        )

        if response.status_code == status.HTTP_201_CREATED:
            data = response.json()
            # Should include discount information
            assert 'discount' in data
            assert data['promo_code'] == 'WELCOME20'