# LeedPDF

> Privacy-friendly, ADHD-friendly PDF reader and annotator designed for absolute focus.

## Overview
LeedPDF is an exceptionally lightweight, open-source PDF viewing and annotation platform built for students, teachers, and professionals. It was specifically engineered to reduce visual noise and cognitive friction (making it ADHD-friendly), while ensuring absolute localization of all document rendering and processing pipelines. 

## Platforms & Tech Stack
- **Native Applications**: Delivered via Tauri for Windows and macOS.
- **Progressive Web App (PWA)**: Fully installable directly from the browser supporting offline fallback caching via Workbox and standalone display mode for a native app feel.
- **Architecture**: Powered by Svelte 5, Vite, and high-performance Web-based rendering architectures.

## Core Features
1. **Hybrid Annotation System**
   - **Freehand Canvas**: Low-latency, ultra-smooth freehand pencil drawing and erasing with custom SVG hotspot targeting (e.g. pencil `2,18` alignment).
   - **Vector Overlays**: Inject cleanly mathematical rectangles, circles, pointing arrows, and typed text.
   - **Natural Highlighting**: High-contrast, behind-the-text highlighter tracking to prevent visual conflicts with the underlying PDF document lines.

2. **Keyboard Optimization & Ergonomics**
   - A vast ecosystem of hotkeys designed for power users traversing large documents.
   - Arrow keys for pagination, `1-6` for tool swapping, `W/H` for auto fit-to-width/height calculation, `T` for sidebar thumbnails, `Ctrl+/-` for deep zooming, and `U` for instant file uploading. 
   - A fully responsive shortcuts overlay modal (via `?` or `F1`).

3. **Data Security & Privacy**
   - Strictly local execution. PDFs never leave the device.
   - No tracking telemetry, no backend account creation, no artificial web bottlenecks.

4. **PDF Engine Capabilities**
   - **Local Compression**: Shrink massive PDFs up to 80% dynamically within the browser without server round-trips.
   - **Page Reorganization**: Merge multiple PDFs, split documents, delete individual pages, or rotate orientations (`R` / `Shift+R`).
   - **Format Conversion**: Convert images instantly to PDF, or tear-down a PDF into PNG images and Word (.docx) formats.
   - **Presentation Mode**: True distraction-free fullscreen mode (`F11`) for live presentations and lecturing.

5. **Auto-Save Workflows**
   - Background saving system tethering local storage keys matching document signatures (FileName + FileSize). Reopening a long un-opened document will seamlessly restore the exact drawing vectors.
   - Full Export capabilities generating `_annotated.pdf` pipelines with high-resolution device pixel ratio merging between canvas annotations and raw PDF objects.
   
## Accessibility & Philosophy
- **ADHD Driven**: Eliminating the crowded "ribbon interfaces" notorious in ancient PDF applications. Reduced decision fatigue.
- Supports multi-input flawlessly handling physical cursors, tactile touch interactions, and deeply integrated stylus feedback.
- Custom topography detection relying on native OS fonts (Windows/Mac) ensuring professional aesthetics natively.

## Licensing & Resources
- **License**: Strictly Open Source (AGPL-3.0).
- **Website**: [leedpdf.com](https://leedpdf.com)
- **Source**: Find it via internal channels or the contact page.
- **Contact**: hello@leedpdf.com