"""Offline validation regressions; no camera, server or credentials are contacted."""
import base64
from datetime import datetime, timezone
import importlib.util
import json
from pathlib import Path
import struct
import tempfile
import time
import unittest
from unittest.mock import patch
import zlib

spec = importlib.util.spec_from_file_location('camera_capture', Path(__file__).with_name('camera-capture.py'))
camera = importlib.util.module_from_spec(spec)
spec.loader.exec_module(camera)


def chunk(kind, data):
    return struct.pack('>I', len(data)) + kind + data + struct.pack('>I', zlib.crc32(kind + data) & 0xffffffff)


PNG = b'\x89PNG\r\n\x1a\n' + chunk(b'IHDR', struct.pack('>IIBBBBB', 1, 1, 8, 2, 0, 0, 0)) + chunk(b'IDAT', zlib.compress(b'\0\0\0\0')) + chunk(b'IEND', b'')
TOKEN = 'private-test-token-' * 3
CAPTURE_ID = '11111111-1111-4111-8111-111111111111'
POSE = dict(x=0, y=100, z=0, yaw=0, pitch=30, dimension='minecraft:overworld', fov=80, width=1280, height=720)


class CameraCaptureTest(unittest.TestCase):
    def reply(self):
        return dict(status='completed', captureId=CAPTURE_ID, mimeType='image/png', dimension=POSE['dimension'],
                    capturedAt=datetime.now(timezone.utc).isoformat(), width=1, height=1, imageBase64=base64.b64encode(PNG).decode())

    def test_invalid_request_fails_before_config_or_transport(self):
        for change in ({'x': float('nan')}, {'pitch': 91}, {'yaw': -361}, {'y': 2049}, {'fov': 29}, {'width': True}, {'dimension': 'https://example.com'}, {'x': '0'}):
            with self.subTest(change=change), patch.object(camera.checks, 'request_json') as request:
                with self.assertRaises(camera.checks.TestFailure):
                    camera.capture('/does/not/exist', POSE | change, '/unused')
                request.assert_not_called()

    def test_raw_image_is_unchanged_and_metadata_allowlisted(self):
        result = self.reply() | {'arbitrary': {'secret': TOKEN}}
        raw, receipt = camera.validated_image(result, CAPTURE_ID, POSE, TOKEN, time.time())
        self.assertEqual(raw, PNG)
        metadata = json.loads(receipt)
        self.assertTrue(metadata['operator_direct_worker'])
        self.assertEqual(metadata['imageBytes'], len(PNG))
        self.assertNotIn('arbitrary', metadata)
        self.assertNotIn('imageBase64', metadata)

    def test_wrong_identity_dimension_timestamp_and_size_rejected(self):
        for change in ({'captureId': '22222222-2222-4222-8222-222222222222'}, {'dimension': 'minecraft:the_nether'}, {'width': 2}, {'mimeType': 'image/jpeg'}, {'capturedAt': '2020-01-01T00:00:00Z'}):
            with self.subTest(change=change), self.assertRaises(camera.checks.TestFailure):
                camera.validated_image(self.reply() | change, CAPTURE_ID, POSE, TOKEN, time.time())

    def test_bad_png_and_private_metadata_rejected(self):
        corrupt = bytearray(PNG);corrupt[30] ^= 1
        for change in ({'imageBase64': 'bad!'}, {'imageBase64': base64.b64encode(corrupt).decode()}, {'readiness': TOKEN}, {'readiness': {}}, {'eyeY': float('nan')}):
            with self.subTest(change=change), self.assertRaises(camera.checks.TestFailure):
                camera.validated_image(self.reply() | change, CAPTURE_ID, POSE, TOKEN, time.time())

    def test_polled_capture_cannot_switch_identity(self):
        with tempfile.TemporaryDirectory() as temp:
            root = Path(temp);config = root / 'config.yml';output = root / 'frame.png'
            config.write_text(f'camera-token: {TOKEN}\ncamera-port: 8766\n')
            responses = [dict(status='pending', captureId=CAPTURE_ID), self.reply() | {'captureId': '22222222-2222-4222-8222-222222222222'}]
            with patch.object(camera.checks, 'request_json', side_effect=responses), patch.object(camera.time, 'sleep'):
                with self.assertRaises(camera.checks.TestFailure):camera.capture(config, POSE, output)
            self.assertFalse(output.exists())

    def test_oversized_and_nonobject_http_response_rejected(self):
        class Response:
            def __init__(self, raw):self.raw=raw
            def __enter__(self):return self
            def __exit__(self, *args):pass
            def read(self, limit):return self.raw[:limit]
        class Opener:
            def __init__(self, raw):self.raw=raw
            def open(self, *args, **kwargs):return Response(self.raw)
        for raw in (b'[]', b'x' * (camera.checks.MAX_RESPONSE + 1)):
            with self.assertRaises(camera.checks.TestFailure):
                camera.checks.request_json(Opener(raw), 'http://127.0.0.1:8766/health', TOKEN)


if __name__ == '__main__':unittest.main()