"""
Verification script for Bug #66: CrashLoopBackOff fix.

Root cause: Two uncommitted changes caused Django migration drift in the
Docker container:
1. MODEL_CHOICES labels changed from 'Seedance 2.0' to 'AirDrama' in models.py
   but migration 0004 (which records this change) was untracked by git.
2. Index name='generation__user_id_371350_idx' was added to models.py but not
   committed — the migration already had this name.

Without migration 0004 in the Docker image, Django detected model-migration
mismatch at startup, causing the pod to enter CrashLoopBackOff.

Fix: Commit both models.py (with explicit index name) and migration 0004.
"""
import os
import sys
import subprocess

# Ensure we're in the backend directory
BACKEND_DIR = os.path.dirname(os.path.abspath(__file__))
if os.path.basename(BACKEND_DIR) != 'backend':
    BACKEND_DIR = os.path.join(BACKEND_DIR, 'backend')

os.chdir(BACKEND_DIR)
sys.path.insert(0, BACKEND_DIR)
os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'config.settings')


def test_django_check():
    """Verify Django system check passes with no issues."""
    result = subprocess.run(
        [sys.executable, 'manage.py', 'check'],
        capture_output=True, text=True, cwd=BACKEND_DIR,
    )
    assert result.returncode == 0, f"Django check failed:\n{result.stderr}"
    print("PASS: Django system check — no issues found")


def test_no_pending_migrations():
    """Verify there are no pending migrations (the root cause of Bug #66)."""
    result = subprocess.run(
        [sys.executable, 'manage.py', 'makemigrations', '--check', '--dry-run'],
        capture_output=True, text=True, cwd=BACKEND_DIR,
    )
    assert result.returncode == 0, (
        f"Pending migrations detected (this was the Bug #66 root cause):\n"
        f"{result.stdout}\n{result.stderr}"
    )
    print("PASS: No pending migrations detected")


def test_index_name_matches_migration():
    """Verify the model index name matches what's in the migration file."""
    import django
    django.setup()

    from apps.generation.models import GenerationRecord

    meta_indexes = GenerationRecord._meta.indexes
    assert len(meta_indexes) >= 1, "GenerationRecord should have at least 1 index"

    user_created_index = meta_indexes[0]
    assert user_created_index.name == 'generation__user_id_371350_idx', (
        f"Index name mismatch: got '{user_created_index.name}', "
        f"expected 'generation__user_id_371350_idx'"
    )
    print("PASS: Index name matches migration file")


def test_migration_0004_exists():
    """Verify migration 0004 for model choice label change exists."""
    migration_path = os.path.join(
        BACKEND_DIR, 'apps', 'generation', 'migrations',
        '0004_alter_generationrecord_model.py'
    )
    assert os.path.exists(migration_path), (
        f"Migration 0004 not found at {migration_path}"
    )
    print("PASS: Migration 0004 exists")


def test_model_choices_match_migration():
    """Verify MODEL_CHOICES values match what migration 0004 expects."""
    import django
    django.setup()

    from apps.generation.models import GenerationRecord

    choices_dict = dict(GenerationRecord.MODEL_CHOICES)
    assert choices_dict.get('seedance_2.0') == 'AirDrama', (
        f"Expected 'AirDrama', got {choices_dict.get('seedance_2.0')!r}"
    )
    assert choices_dict.get('seedance_2.0_fast') == 'AirDrama Fast', (
        f"Expected 'AirDrama Fast', got {choices_dict.get('seedance_2.0_fast')!r}"
    )
    print("PASS: MODEL_CHOICES labels match migration 0004")


def test_wsgi_loads():
    """Verify WSGI application loads (gunicorn entrypoint)."""
    import django
    django.setup()

    from config.wsgi import application
    assert application is not None, "WSGI application failed to load"
    print("PASS: WSGI application loads successfully")


if __name__ == '__main__':
    tests = [
        test_django_check,
        test_no_pending_migrations,
        test_index_name_matches_migration,
        test_migration_0004_exists,
        test_model_choices_match_migration,
        test_wsgi_loads,
    ]
    passed = failed = 0
    for test in tests:
        try:
            test()
            passed += 1
        except Exception as e:
            print(f"FAIL: {test.__name__}: {e}")
            failed += 1

    print(f"\nResults: {passed} passed, {failed} failed")
    sys.exit(1 if failed else 0)