pdf.cu3rd.ru (CU 3rd Party PDF Editor)

A client-side web application designed to parse, modify, and reverse-engineer official educational PDFs from Central University (CU). This tool allows users to safely convert official academic materials into a beautifully integrated Dark Mode layout natively, modifying the raw PDF drawing instructions directly in the browser.

Features

• Zero-Backend Processing: All PDF parsing, decompression (pako), and color mapping logic (pdf-lib) executes securely on the client side. No documents are uploaded to any server.
• Deep Stream Modification: The system recursively traverses and replaces colors across all CMYK, RGB, and Grayscale color spaces inside both regular /Contents streams and complex LaTeX /Form XObjects.
• Live Palette Editor: Upload any PDF to interactively remap color palettes. Live preview is provided by a localized pdf.js worker. Custom JSON palettes can be imported or exported for sharing.
• CU Dark Theme Aesthetics: The interface aligns with the official minimalistic CU 3rd-party design guidelines (#212121 backgrounds, #f2f2f4 accents, and the simplified geometric CU icon).

Tech Stack

• Framework: React 18, Vite
• PDF Parsing & Editing: pdf-lib (binary manipulation), pako (Zlib streams)
• PDF Rendering: pdf.js (for interactive previews)
• Styling: Vanilla CSS, configured to match the cu-roadmap dark theme variables.

Getting Started

Local Development

1. Install dependencies:

   npm install
   

2. Start the development server:

   npm run dev
   

   The application will be accessible at http://localhost:8790.

Docker Deployment

This repository includes a multi-stage Dockerfile and a docker-compose.yml for quick, production-ready deployment via an Nginx alpine container.

1. Build and run the container in detached mode:

   docker-compose up -d --build
   

2. The application will be immediately available on your host at port 8790.

Architecture Details

The core processing logic is located in src/lib/pdfDarkTheme.js. It performs raw bytes manipulation inside PDF content streams. It is deliberately written without heavy framework dependencies to ensure it can be easily ported into a Chrome Extension (e.g., via a content_script or background worker) in future updates.