fix(example-images): reuse migrated folders during downloads

tests/services/test_example_images_download_manager_async.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import asyncio
+import json
 from types import SimpleNamespace
 
 import pytest
@@ -226,3 +227,152 @@ async def test_pause_resume_blocks_processing(monkeypatch: pytest.MonkeyPatch, t
         if manager._download_task is not None:
             await asyncio.wait_for(manager._download_task, timeout=1)
         monkeypatch.setattr(download_module.asyncio, "sleep", original_sleep)
+
+
+@pytest.mark.usefixtures("tmp_path")
+async def test_legacy_folder_migrated_and_skipped(monkeypatch: pytest.MonkeyPatch, tmp_path):
+    ws_manager = RecordingWebSocketManager()
+    manager = download_module.DownloadManager(ws_manager=ws_manager)
+
+    monkeypatch.setitem(settings.settings, "example_images_path", str(tmp_path))
+    monkeypatch.setitem(settings.settings, "libraries", {"default": {}, "extra": {}})
+    monkeypatch.setitem(settings.settings, "active_library", "extra")
+
+    model_hash = "d" * 64
+    model_path = tmp_path / "model.safetensors"
+    model_path.write_text("data", encoding="utf-8")
+
+    model = {
+        "sha256": model_hash,
+        "model_name": "Migrated Model",
+        "file_path": str(model_path),
+        "file_name": "model.safetensors",
+        "civitai": {"images": [{"url": "https://example.com/image.png"}]},
+    }
+
+    _patch_scanner(monkeypatch, StubScanner([model]))
+
+    legacy_folder = tmp_path / model_hash
+    legacy_folder.mkdir()
+    (legacy_folder / "image_0.png").write_text("data", encoding="utf-8")
+
+    process_called = False
+    download_called = False
+
+    async def fake_process_local_examples(*_args, **_kwargs):
+        nonlocal process_called
+        process_called = True
+        return False
+
+    async def fake_download_model_images(*_args, **_kwargs):
+        nonlocal download_called
+        download_called = True
+        return True, False
+
+    async def fake_get_downloader():
+        class _Downloader:
+            async def download_to_memory(self, *_a, **_kw):
+                return True, b"", {}
+
+        return _Downloader()
+
+    monkeypatch.setattr(
+        download_module.ExampleImagesProcessor,
+        "process_local_examples",
+        staticmethod(fake_process_local_examples),
+    )
+    monkeypatch.setattr(
+        download_module.ExampleImagesProcessor,
+        "download_model_images",
+        staticmethod(fake_download_model_images),
+    )
+    monkeypatch.setattr(download_module, "get_downloader", fake_get_downloader)
+
+    try:
+        result = await manager.start_download({"model_types": ["lora"], "delay": 0})
+        assert result["success"] is True
+
+        if manager._download_task is not None:
+            await asyncio.wait_for(manager._download_task, timeout=1)
+    finally:
+        if manager._download_task is not None and not manager._download_task.done():
+            await asyncio.wait_for(manager._download_task, timeout=1)
+
+    library_root = tmp_path / "extra"
+    migrated_folder = library_root / model_hash
+
+    assert migrated_folder.exists()
+    assert not legacy_folder.exists()
+    assert not process_called
+    assert not download_called
+    assert model_hash in manager._progress["processed_models"]
+
+
+@pytest.mark.usefixtures("tmp_path")
+async def test_legacy_progress_file_migrates(monkeypatch: pytest.MonkeyPatch, tmp_path):
+    ws_manager = RecordingWebSocketManager()
+    manager = download_module.DownloadManager(ws_manager=ws_manager)
+
+    monkeypatch.setitem(settings.settings, "example_images_path", str(tmp_path))
+    monkeypatch.setitem(settings.settings, "libraries", {"default": {}, "extra": {}})
+    monkeypatch.setitem(settings.settings, "active_library", "extra")
+
+    model_hash = "e" * 64
+    model_path = tmp_path / "model-two.safetensors"
+    model_path.write_text("data", encoding="utf-8")
+
+    legacy_progress = tmp_path / ".download_progress.json"
+    legacy_progress.write_text(json.dumps({"processed_models": [model_hash], "failed_models": []}), encoding="utf-8")
+
+    legacy_folder = tmp_path / model_hash
+    legacy_folder.mkdir()
+    (legacy_folder / "existing.png").write_text("data", encoding="utf-8")
+
+    model = {
+        "sha256": model_hash,
+        "model_name": "Legacy Progress Model",
+        "file_path": str(model_path),
+        "file_name": "model-two.safetensors",
+        "civitai": {"images": [{"url": "https://example.com/image.png"}]},
+    }
+
+    _patch_scanner(monkeypatch, StubScanner([model]))
+
+    async def fake_process_local_examples(*_args, **_kwargs):
+        return False
+
+    async def fake_download_model_images(*_args, **_kwargs):
+        raise AssertionError("Remote download should not be attempted when progress is migrated")
+
+    async def fake_get_downloader():
+        class _Downloader:
+            async def download_to_memory(self, *_a, **_kw):
+                return True, b"", {}
+
+        return _Downloader()
+
+    monkeypatch.setattr(
+        download_module.ExampleImagesProcessor,
+        "process_local_examples",
+        staticmethod(fake_process_local_examples),
+    )
+    monkeypatch.setattr(
+        download_module.ExampleImagesProcessor,
+        "download_model_images",
+        staticmethod(fake_download_model_images),
+    )
+    monkeypatch.setattr(download_module, "get_downloader", fake_get_downloader)
+
+    result = await manager.start_download({"model_types": ["lora"], "delay": 0})
+    assert result["success"] is True
+
+    if manager._download_task is not None:
+        await asyncio.wait_for(manager._download_task, timeout=1)
+
+    new_progress = (tmp_path / "extra") / ".download_progress.json"
+
+    assert model_hash in manager._progress["processed_models"]
+    assert not legacy_progress.exists()
+    assert new_progress.exists()
+    contents = json.loads(new_progress.read_text(encoding="utf-8"))
+    assert model_hash in contents.get("processed_models", [])