feat(assistant): file kinds and dropped URLs

Files.js decides what the card offers for a staged file; the daemon decides what chat accepts, so the text and image lists match its own. Dropped URLs become paths only for file:// ones.

Co-Authored-By: Claude Haiku 5.5 <noreply@anthropic.com>

2 files changed, 95 insertions, 0 deletions

diff --git a/desktop/assistant/Files.js b/desktop/assistant/Files.js
new file mode 100644
index 0000000..b7f8c2b
--- /dev/null
+++ b/desktop/assistant/Files.js
@@ -0,0 +1,55 @@
+// Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 2 as
+// published by the Free Software Foundation.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+.pragma library
+
+// What a staged file is, for its chip and the actions offered on it. The
+// text and image lists match desktop-assistant's, which decides what chat
+// accepts; this only decides what the card offers.
+// ponytail: the daemon also takes any text/* mime type; a file of such a
+// type with a suffix not listed here reads as "other" and is not offered
+// chat. Add the suffix when one shows up.
+const TEXT = [".py", ".c", ".h", ".cpp", ".hpp", ".rs", ".go", ".js", ".ts", ".jsx",
+              ".tsx", ".sh", ".bash", ".zsh", ".lua", ".rb", ".pl", ".php", ".java",
+              ".kt", ".swift", ".sql", ".toml", ".yaml", ".yml", ".json", ".ini",
+              ".cfg", ".conf", ".md", ".rst", ".txt", ".csv", ".xml", ".html", ".css",
+              ".diff", ".patch", ".slackbuild", ".info", ".desktop", ".service", ".qml"];
+const IMAGE = [".png", ".jpg", ".jpeg", ".gif", ".webp"];
+const VIDEO = [".mp4", ".mkv", ".webm", ".mov", ".avi", ".m4v"];
+const ARCHIVE = [".zip", ".tar", ".gz", ".tgz", ".xz", ".txz", ".bz2", ".zst", ".7z", ".rar"];
+
+// Kinds chat takes; the rest only get local actions.
+const CHAT = ["text", "image", "pdf"];
+
+function name(path) { return path.slice(path.lastIndexOf("/") + 1); }
+
+function kind(path) {
+    const n = name(path).toLowerCase();
+    const dot = n.lastIndexOf(".");
+    const ext = dot > 0 ? n.slice(dot) : "";
+    if (ext === ".pdf") return "pdf";
+    if (IMAGE.includes(ext)) return "image";
+    if (VIDEO.includes(ext)) return "video";
+    if (ARCHIVE.includes(ext)) return "archive";
+    if (TEXT.includes(ext)) return "text";
+    return "other";
+}
+
+function chats(k) { return CHAT.includes(k); }
+
+// A dropped URL to a local path, or "" for anything that is not a file.
+function fromUrl(url) {
+    const s = String(url);
+    if (!s.startsWith("file://")) return "";
+    try { return decodeURIComponent(s.slice(7)); } catch (e) { return ""; }
+}
+
+function file(path) { return { path: path, name: name(path), kind: kind(path) }; }
diff --git a/desktop/assistant/test_files.js b/desktop/assistant/test_files.js
new file mode 100644
index 0000000..a15495b
--- /dev/null
+++ b/desktop/assistant/test_files.js
@@ -0,0 +1,40 @@
+// Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 2 as
+// published by the Free Software Foundation.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// Run: node desktop/assistant/test_files.js
+// Files.js is a QML library, so its .pragma line is stripped before node
+// evaluates it.
+
+const fs = require("fs");
+const assert = require("assert");
+
+const src = fs.readFileSync(__dirname + "/Files.js", "utf8")
+    .replace(/^\.pragma library$/m, "");
+const F = new Function(src + "\nreturn { kind, chats, fromUrl, file, name };")();
+
+const cases = {
+    "/a/report.pdf": "pdf", "/a/Report.PDF": "pdf", "/a/x.png": "image", "/a/x.JPEG": "image",
+    "/a/clip.mp4": "video", "/a/c.MKV": "video", "/a/src.tar.gz": "archive", "/a/b.7z": "archive",
+    "/a/main.py": "text", "/a/notes.md": "text", "/a/pkg.SlackBuild": "text",
+    "/a/Makefile": "other", "/a/.bashrc": "other", "/a/x.bin": "other", "/a/dir.d/noext": "other",
+};
+for (const [p, k] of Object.entries(cases)) assert.strictEqual(F.kind(p), k, p);
+
+assert.ok(F.chats("pdf") && F.chats("image") && F.chats("text"));
+assert.ok(!F.chats("video") && !F.chats("archive") && !F.chats("other"));
+
+assert.strictEqual(F.fromUrl("file:///home/you/My%20Docs/caf%C3%A9.pdf"), "/home/you/My Docs/café.pdf");
+assert.strictEqual(F.fromUrl("file:///tmp/a.txt"), "/tmp/a.txt");
+assert.strictEqual(F.fromUrl("https://example.org/a.pdf"), "");
+assert.strictEqual(F.fromUrl("file:///bad%E0%A4%A"), "");   // malformed escape
+assert.deepStrictEqual(F.file("/x/y/a b.pdf"), { path: "/x/y/a b.pdf", name: "a b.pdf", kind: "pdf" });
+
+console.log("ok");