"""
T026 — valid JPEG upload → 201, record in DB, object in MinIO
T027 — same image uploaded twice → 200, duplicate: true, no second MinIO object
T028 — invalid MIME type → 422 invalid_mime_type (error envelope with code field)
T029 — file > MAX_UPLOAD_BYTES → 422 file_too_large
T079 — GET /api/v1/images/{id} 404 → error envelope shape
"""
import io
from unittest.mock import patch

import pytest
from PIL import Image as PILImage


def _real_jpeg(color: tuple = (100, 150, 200), size: tuple = (200, 150)) -> bytes:
    buf = io.BytesIO()
    PILImage.new("RGB", size, color=color).save(buf, format="JPEG")
    return buf.getvalue()


def _minimal_jpeg() -> bytes:
    # Minimal valid JPEG bytes (SOI + APP0 + EOI)
    return (
        b"\xff\xd8\xff\xe0\x00\x10JFIF\x00\x01\x01\x00\x00\x01\x00\x01\x00\x00"
        b"\xff\xd9"
    )


@pytest.mark.asyncio
async def test_upload_new_image_returns_201(client):
    data = _minimal_jpeg()
    response = await client.post(
        "/api/v1/images",
        files={"file": ("test.jpg", io.BytesIO(data), "image/jpeg")},
    )
    assert response.status_code == 201
    body = response.json()
    assert body["duplicate"] is False
    assert body["filename"] == "test.jpg"
    assert body["mime_type"] == "image/jpeg"
    assert "id" in body
    assert "hash" in body
    assert len(body["hash"]) == 64


@pytest.mark.asyncio
async def test_upload_duplicate_returns_200_with_flag(client):
    data = _minimal_jpeg()
    # First upload
    r1 = await client.post(
        "/api/v1/images",
        files={"file": ("test.jpg", io.BytesIO(data), "image/jpeg")},
    )
    assert r1.status_code in (200, 201)

    # Second upload of same bytes
    r2 = await client.post(
        "/api/v1/images",
        files={"file": ("test.jpg", io.BytesIO(data), "image/jpeg")},
    )
    assert r2.status_code == 200
    body = r2.json()
    assert body["duplicate"] is True
    assert body["id"] == r1.json()["id"]


@pytest.mark.asyncio
async def test_upload_invalid_mime_type_returns_422(client):
    response = await client.post(
        "/api/v1/images",
        files={"file": ("doc.pdf", io.BytesIO(b"%PDF-1.4"), "application/pdf")},
    )
    assert response.status_code == 422
    body = response.json()
    assert body["code"] == "invalid_mime_type"
    assert "detail" in body


@pytest.mark.asyncio
async def test_upload_oversized_file_returns_422(client):
    import os
    from app.config import get_settings

    os.environ["MAX_UPLOAD_BYTES"] = "10"
    get_settings.cache_clear()

    try:
        response = await client.post(
            "/api/v1/images",
            files={"file": ("big.jpg", io.BytesIO(b"x" * 11), "image/jpeg")},
        )
        assert response.status_code == 422
        body = response.json()
        assert body["code"] == "file_too_large"
    finally:
        del os.environ["MAX_UPLOAD_BYTES"]
        get_settings.cache_clear()


@pytest.mark.asyncio
async def test_get_unknown_image_returns_404_with_envelope(client):
    import uuid
    response = await client.get(f"/api/v1/images/{uuid.uuid4()}")
    assert response.status_code == 404
    body = response.json()
    assert body["code"] == "image_not_found"
    assert "detail" in body


@pytest.mark.asyncio
async def test_upload_returns_thumbnail_key(client):
    data = _real_jpeg(color=(100, 150, 200))
    response = await client.post(
        "/api/v1/images",
        files={"file": ("thumb_test.jpg", io.BytesIO(data), "image/jpeg")},
    )
    assert response.status_code == 201
    body = response.json()
    assert "thumbnail_key" in body
    assert body["thumbnail_key"] is not None
    assert body["thumbnail_key"].endswith("-thumb")


@pytest.mark.asyncio
async def test_duplicate_upload_reuses_thumbnail_key(client):
    data = _real_jpeg(color=(200, 100, 50))
    r1 = await client.post(
        "/api/v1/images",
        files={"file": ("dup.jpg", io.BytesIO(data), "image/jpeg")},
    )
    assert r1.status_code in (200, 201)

    r2 = await client.post(
        "/api/v1/images",
        files={"file": ("dup.jpg", io.BytesIO(data), "image/jpeg")},
    )
    assert r2.status_code == 200

    tk1 = r1.json()["thumbnail_key"]
    tk2 = r2.json()["thumbnail_key"]
    assert tk1 is not None
    assert tk1 == tk2


@pytest.mark.asyncio
async def test_upload_succeeds_when_thumbnail_fails(client):
    data = _real_jpeg(color=(50, 200, 150))
    with patch("app.routers.images.generate_thumbnail", side_effect=RuntimeError("simulated")):
        response = await client.post(
            "/api/v1/images",
            files={"file": ("no_thumb.jpg", io.BytesIO(data), "image/jpeg")},
        )
    assert response.status_code in (200, 201)
    body = response.json()
    assert body["thumbnail_key"] is None