⚡ Text Quick Viewer

Syntax-highlighted instant previews for text and source files inside Nuclr Commander.

No tab switching. No app hopping. Just hit Ctrl+Q and get the file in front of you, fast. 😎

🚀 What It Does

• 🔥 Syntax highlighting for 50+ languages and formats via RSyntaxTextArea
• 🧭 Line numbers for quick scanning and reference
• 🪄 Code folding where the language supports it
• 🌑 Dark styling that fits Commander without looking bolted on
• 🛡️ Large-file guard that stops previews over 10 MB from freezing the UI
• 🧪 Binary-file detection that quietly skips files that should not be rendered as text
• 📦 NIO.2 support, including files inside ZIP and JAR archives
• ⛔ Cancellation-aware loading so switching files does not leave stale content behind

🎯 Supported File Types

Files that match none of the above are still previewed when they look like text: the first 8 KB is decoded as UTF-8 and accepted only if it has no NUL bytes, matches no known binary signature, is at least 85 % printable, and is no more than 60 % whitespace. A #! shebang also qualifies a file, which is how extensionless scripts preview correctly.

🖼️ Thumbnail

The head of the file (16 KB) as a page of monospaced text; binary content has no thumbnail. At icon sizes the lines are drawn as grey bars, the way a document preview looks.

It implements the platform SDK 6.0.0 thumbnail methods, so plugins that want a picture of a file - attachment chips in AI Projects, for one - get it through Commander.

📥 Installation

Copy the signed plugin archive and detached signature into the Nuclr Commander plugins/ directory:

quick-view-text-<version>.zip
quick-view-text-<version>.zip.sig

Nuclr Commander verifies the RSA-SHA256 signature against nuclr-cert.pem on load. The plugin becomes available immediately without a restart.

🧠 How It Works

TextQuickViewProvider  → decides whether a file looks like supported text
TextFileSupport        → extension/filename tables, binary + UTF-8 heuristics, syntax mapping
TextQuickViewPanel     → loads content and renders it in RSyntaxTextArea

Loading flow

1. supports(resource) matches the filename or extension; anything unknown falls through to the 8 KB text heuristic in TextFileSupport.
2. openResource(resource, cancelled) delegates to TextQuickViewPanel.load(...) on a virtual thread.
3. Loading performs:
   • file-size guard (10 MB limit)
   • binary scan of the first 8 KB
   • content read via Path or InputStream
   • EDT handoff for final UI update
4. setText(...) selects the syntax style (by extension, or by filename for things like Dockerfile) and swaps in a fresh document.

Threading model

• EDT: Swing updates, document swaps, repainting
• Virtual thread: file I/O and binary detection
• AtomicBoolean cancelled: prevents stale UI updates when the user changes selection mid-load

🗂️ Source Layout

src/main/java/dev/nuclr/plugin/core/quick/viewer/text/
├── TextQuickViewProvider.java   plugin entry point
├── TextFileSupport.java         format detection, binary/text heuristics, syntax mapping
└── TextQuickViewPanel.java      Swing panel, loading, syntax highlighting

Unit tests for the detection heuristics live in src/test/java/.../TextFileSupportTest.java.

📚 Dependencies

📄 License

Apache 2.0. See LICENSE.