import io
import json
import pytest
import numpy as np
import cv2
from unittest.mock import AsyncMock

from app.core.exceptions import LLMParseError
from app.models.image_models import ImageExtractRequest


def _make_test_image_bytes(width=100, height=80) -> bytes:
    img = np.zeros((height, width, 3), dtype=np.uint8)
    img[10:50, 10:60] = (255, 0, 0)  # blue rectangle
    _, buf = cv2.imencode(".jpg", img)
    return buf.tobytes()


SAMPLE_QUADS_JSON = json.dumps([
    {
        "subject": "电缆接头",
        "predicate": "位于",
        "object": "配电箱左侧",
        "qualifier": "2024年检修",
        "bbox": {"x": 10, "y": 10, "w": 40, "h": 30},
    }
])


@pytest.fixture
def image_bytes():
    return _make_test_image_bytes()


@pytest.fixture
def req():
    return ImageExtractRequest(file_path="image/test.jpg", task_id=1)


@pytest.mark.asyncio
async def test_extract_quads_returns_items(mock_llm, mock_storage, image_bytes, req):
    mock_storage.download_bytes = AsyncMock(return_value=image_bytes)
    mock_llm.chat_vision = AsyncMock(return_value=SAMPLE_QUADS_JSON)
    mock_storage.upload_bytes = AsyncMock(return_value=None)

    from app.services.image_service import extract_quads
    result = await extract_quads(req, mock_llm, mock_storage)

    assert len(result.items) == 1
    item = result.items[0]
    assert item.subject == "电缆接头"
    assert item.predicate == "位于"
    assert item.bbox.x == 10
    assert item.bbox.y == 10
    assert item.cropped_image_path == "crops/1/0.jpg"


@pytest.mark.asyncio
async def test_crop_is_uploaded(mock_llm, mock_storage, image_bytes, req):
    mock_storage.download_bytes = AsyncMock(return_value=image_bytes)
    mock_llm.chat_vision = AsyncMock(return_value=SAMPLE_QUADS_JSON)
    mock_storage.upload_bytes = AsyncMock(return_value=None)

    from app.services.image_service import extract_quads
    await extract_quads(req, mock_llm, mock_storage)

    # upload_bytes called once for the crop
    mock_storage.upload_bytes.assert_called_once()
    call_args = mock_storage.upload_bytes.call_args
    assert call_args.args[1] == "crops/1/0.jpg"


@pytest.mark.asyncio
async def test_out_of_bounds_bbox_is_clamped(mock_llm, mock_storage, req):
    img = _make_test_image_bytes(width=50, height=40)
    mock_storage.download_bytes = AsyncMock(return_value=img)

    # bbox goes outside image boundary
    oob_json = json.dumps([{
        "subject": "test",
        "predicate": "rel",
        "object": "obj",
        "qualifier": None,
        "bbox": {"x": 30, "y": 20, "w": 100, "h": 100},  # extends beyond 50x40
    }])
    mock_llm.chat_vision = AsyncMock(return_value=oob_json)
    mock_storage.upload_bytes = AsyncMock(return_value=None)

    from app.services.image_service import extract_quads
    # Should not raise; bbox is clamped
    result = await extract_quads(req, mock_llm, mock_storage)
    assert len(result.items) == 1


@pytest.mark.asyncio
async def test_llm_parse_error_raised(mock_llm, mock_storage, image_bytes, req):
    mock_storage.download_bytes = AsyncMock(return_value=image_bytes)
    mock_llm.chat_vision = AsyncMock(return_value="bad json {{")

    from app.services.image_service import extract_quads
    with pytest.raises(LLMParseError):
        await extract_quads(req, mock_llm, mock_storage)