feat(modals): GET /overlays/<id>/files/edit route

Server-renders the file editor as a real page. With HX-Modal:1 returns
a layoutless fragment for modal embedding; without it returns the full
standalone page. Mirrors overlay_file_content's path/editability checks.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

l4d2web/l4d2web/routes/files_routes.py

@@ -234,6 +234,47 @@ def overlay_file_content(overlay_id: int):
     return jsonify({"path": sub_path, "content": content})
 
 
+@bp.get("/overlays/<int:overlay_id>/files/edit")
+@require_login
+def overlay_file_edit_page(overlay_id: int):
+    """Server-rendered editor page. Renders full-page by default or as a
+    layoutless modal fragment when the HX-Modal header is set (see the
+    inject_base_layout context processor in app.py)."""
+    user = current_user()
+    assert user is not None
+    sub_path = request.args.get("path", "")
+
+    result = _load_files_overlay(overlay_id, user)
+    if isinstance(result, Response):
+        return result
+    overlay = result
+
+    try:
+        target = safe_resolve_for_listing(overlay.path, sub_path)
+    except ValueError:
+        return Response("invalid path", status=400)
+
+    if not target.exists() or not target.is_file():
+        return Response(status=404)
+    if not is_editable(target):
+        return Response("not editable", status=415)
+
+    try:
+        content = target.read_text(encoding="utf-8")
+    except OSError:
+        return Response("read failed", status=500)
+    except UnicodeDecodeError:
+        return Response("not editable", status=415)
+
+    return render_template(
+        "overlay_file_editor.html",
+        overlay=overlay,
+        rel_path=sub_path,
+        content=content,
+        byte_count=len(content.encode("utf-8")),
+    )
+
+
 def _validate_save_content(content: str) -> Response | None:
     if len(content.encode("utf-8")) > _SAVE_MAX_BYTES:
         return Response("content exceeds 1 MiB", status=413)

l4d2web/tests/test_url_addressable_modals.py

@@ -1,6 +1,11 @@
+from datetime import UTC, datetime
+
 from flask import render_template_string
 
 from l4d2web.app import create_app
+from l4d2web.auth import hash_password
+from l4d2web.db import init_db, session_scope
+from l4d2web.models import Overlay, User
 
 
 def _make_app(tmp_path, monkeypatch, db_name: str):
@@ -27,3 +32,107 @@ def test_base_layout_does_not_react_to_plain_hx_request_header(tmp_path, monkeyp
     app = _make_app(tmp_path, monkeypatch, "layout-hxreq.db")
     with app.test_request_context("/", headers={"HX-Request": "true"}):
         assert render_template_string("{{ base_layout }}") == "base.html"
+
+
+def _auth_client_with_files_overlay(tmp_path, monkeypatch, db_name: str):
+    db_url = f"sqlite:///{tmp_path/db_name}"
+    monkeypatch.setenv("DATABASE_URL", db_url)
+    monkeypatch.setenv("LEFT4ME_ROOT", str(tmp_path))
+    app = create_app({"TESTING": True, "DATABASE_URL": db_url, "SECRET_KEY": "test"})
+    init_db()
+
+    with session_scope() as session:
+        user = User(username="alice", password_digest=hash_password("secret"), admin=False)
+        session.add(user)
+        session.flush()
+        overlay = Overlay(name="cfgs", path="", type="files", user_id=user.id)
+        session.add(overlay)
+        session.flush()
+        overlay.path = str(overlay.id)
+        overlay_root = tmp_path / "overlays" / str(overlay.id)
+        overlay_root.mkdir(parents=True)
+        (overlay_root / "server.cfg").write_text("hostname \"left4me\"\nrcon_password \"hunter2\"\n", encoding="utf-8")
+        user_id = user.id
+        overlay_id = overlay.id
+
+    client = app.test_client()
+    with client.session_transaction() as sess:
+        sess["user_id"] = user_id
+        sess["pw_changed_at"] = datetime.now(UTC).isoformat()
+    return client, overlay_id
+
+
+def test_edit_route_renders_full_page_without_modal_header(tmp_path, monkeypatch):
+    client, overlay_id = _auth_client_with_files_overlay(tmp_path, monkeypatch, "edit-full.db")
+    response = client.get(f"/overlays/{overlay_id}/files/edit?path=server.cfg")
+    text = response.get_data(as_text=True)
+
+    assert response.status_code == 200
+    assert "<!doctype html>" in text.lower()  # full base.html rendered
+    assert 'href="/dashboard"' in text  # nav present
+    assert 'class="files-editor-content"' in text
+    assert 'rcon_password' in text  # content pre-filled
+
+
+def test_edit_route_renders_fragment_with_modal_header(tmp_path, monkeypatch):
+    client, overlay_id = _auth_client_with_files_overlay(tmp_path, monkeypatch, "edit-fragment.db")
+    response = client.get(
+        f"/overlays/{overlay_id}/files/edit?path=server.cfg",
+        headers={"HX-Modal": "1"},
+    )
+    text = response.get_data(as_text=True)
+
+    assert response.status_code == 200
+    assert "<html" not in text  # layoutless
+    assert 'class="primary-nav"' not in text
+    assert 'class="files-editor-content"' in text
+    assert "hostname" in text  # content pre-filled
+
+
+def test_edit_route_404s_for_missing_file(tmp_path, monkeypatch):
+    client, overlay_id = _auth_client_with_files_overlay(tmp_path, monkeypatch, "edit-404.db")
+    response = client.get(f"/overlays/{overlay_id}/files/edit?path=nonexistent.cfg")
+    assert response.status_code == 404
+
+
+def test_edit_route_415s_for_non_editable_file(tmp_path, monkeypatch):
+    client, overlay_id = _auth_client_with_files_overlay(tmp_path, monkeypatch, "edit-415.db")
+    # Forge a non-editable file by writing binary garbage.
+    from pathlib import Path
+    overlay_root = tmp_path / "overlays" / str(overlay_id)
+    Path(overlay_root).joinpath("blob.bin").write_bytes(b"\x00\x01\x02\x03" * 1024)
+
+    response = client.get(f"/overlays/{overlay_id}/files/edit?path=blob.bin")
+    assert response.status_code == 415
+
+
+def test_edit_route_400s_for_path_traversal(tmp_path, monkeypatch):
+    client, overlay_id = _auth_client_with_files_overlay(tmp_path, monkeypatch, "edit-400.db")
+    response = client.get(f"/overlays/{overlay_id}/files/edit?path=../../etc/passwd")
+    assert response.status_code == 400
+
+
+def test_edit_route_404s_for_non_files_overlay(tmp_path, monkeypatch):
+    db_url = f"sqlite:///{tmp_path/'edit-script-overlay.db'}"
+    monkeypatch.setenv("DATABASE_URL", db_url)
+    monkeypatch.setenv("LEFT4ME_ROOT", str(tmp_path))
+    app = create_app({"TESTING": True, "DATABASE_URL": db_url, "SECRET_KEY": "test"})
+    init_db()
+    with session_scope() as s:
+        user = User(username="alice", password_digest=hash_password("secret"), admin=False)
+        s.add(user)
+        s.flush()
+        overlay = Overlay(name="scripted", path="", type="script", user_id=user.id)
+        s.add(overlay)
+        s.flush()
+        overlay.path = str(overlay.id)
+        (tmp_path / "overlays" / str(overlay.id)).mkdir(parents=True)
+        user_id = user.id
+        overlay_id = overlay.id
+    client = app.test_client()
+    with client.session_transaction() as sess:
+        sess["user_id"] = user_id
+        sess["pw_changed_at"] = datetime.now(UTC).isoformat()
+
+    response = client.get(f"/overlays/{overlay_id}/files/edit?path=anything.cfg")
+    assert response.status_code == 404