from django.contrib.auth import get_user_model
from django.test import TestCase
from rest_framework.test import APIClient

from apps.accounts.models import Role, TeacherProfile
from apps.courses.models import Course, CourseStatus
from apps.payments.models import Gateway, Order, OrderStatus

User = get_user_model()


def _teacher(phone, name="T", approved=True):
    u = User.objects.create_user(phone_number=phone, full_name=name, role=Role.TEACHER)
    TeacherProfile.objects.create(user=u, is_approved=approved, bio=f"bio of {name}", headline=f"{name} headline")
    return u


def _student(phone="09120000099"):
    return User.objects.create_user(phone_number=phone, full_name="Student", role=Role.STUDENT)


def _course(instructor, title="C", published=True, price_toman=None):
    c = Course.objects.create(
        instructor=instructor, title=title, tagline="T", description="D",
        level="beginner", language="fa", price_toman=price_toman,
    )
    if published:
        c.publish()
    return c


class InstructorPublicEndpointsTests(TestCase):
    def setUp(self):
        self.client = APIClient()
        self.t1 = _teacher("09120000001", name="Arash")
        self.t2 = _teacher("09120000002", name="Neda")
        # t1: 2 courses, t2: 0 courses
        _course(self.t1, title="C1")
        _course(self.t1, title="C2")

    def test_list_instructors_returns_all_teachers_with_counts(self):
        r = self.client.get("/api/instructors/")
        self.assertEqual(r.status_code, 200)
        body = r.json()
        ids = {row["id"]: row for row in body}
        self.assertIn(self.t1.id, ids)
        self.assertIn(self.t2.id, ids)
        self.assertEqual(ids[self.t1.id]["courses_count"], 2)
        self.assertEqual(ids[self.t1.id]["students_count"], 0)
        self.assertEqual(ids[self.t2.id]["courses_count"], 0)

    def test_instructor_detail_returns_bio_courses_stats(self):
        r = self.client.get(f"/api/instructors/{self.t1.id}/")
        self.assertEqual(r.status_code, 200)
        body = r.json()
        self.assertEqual(body["id"], self.t1.id)
        self.assertEqual(body["full_name"], "Arash")
        self.assertEqual(body["headline"], "Arash headline")
        self.assertEqual(body["bio"], "bio of Arash")
        self.assertEqual(body["courses_count"], 2)
        self.assertEqual(len(body["courses"]), 2)

    def test_instructor_detail_404_for_non_teacher(self):
        s = _student()
        r = self.client.get(f"/api/instructors/{s.id}/")
        self.assertEqual(r.status_code, 404)

    def test_students_count_increments_with_paid_orders(self):
        course = _course(self.t1, title="Sold", price_toman=1000)
        s1 = _student("09120000091")
        s2 = _student("09120000092")
        Order.objects.create(student=s1, course=course, amount_toman=1000, gateway=Gateway.CONSOLE, status=OrderStatus.PAID)
        Order.objects.create(student=s2, course=course, amount_toman=1000, gateway=Gateway.CONSOLE, status=OrderStatus.PAID)
        # Same student buys again — should still count as 1 unique student
        Order.objects.create(student=s1, course=course, amount_toman=1000, gateway=Gateway.CONSOLE, status=OrderStatus.PAID)
        r = self.client.get(f"/api/instructors/{self.t1.id}/")
        self.assertEqual(r.json()["students_count"], 2)