AI-powered PDF reader that lets you select text or screenshot regions and ask questions about them. Built with Next.js, Gemini, and react-pdf.

• Text & area selection -- highlight text or screenshot any region of a PDF, then ask AI about it
• Streaming chat -- responses stream in real-time with full Markdown and LaTeX math rendering
• Multi-turn conversations -- follow-up questions with full context preserved
• Multiple selections per chat -- attach several selections to a single conversation
• Tabs -- open multiple PDFs side by side, drag to reorder, state persists per tab
• Drag & drop -- drop PDF files directly into the app, or paste a URL
• Dark mode -- toggle between light and dark themes
• Zoom -- 50%--200% with 10% increments

• Node.js 20+
• A Google AI Studio API key

git clone <repo-url>
cd pdfnotes
npm install

Create a .env file:

GEMINI_API_KEY=your-api-key-here

npm run dev

Open http://localhost:3000.

1. Upload a PDF (file picker, drag & drop, or URL)
2. Select text or use the screenshot tool to capture a region
3. Click New Chat to start a conversation about your selection
4. Ask follow-up questions or add more selections to the same chat

Chats appear in a sidebar anchored to the location of the selection on the page. Each chat is minimizable and persists across tab switches.

app/
├── api/
│   ├── ask/route.ts              # Streaming chat endpoint
│   └── generate-title/route.ts   # Auto-generates chat titles
├── components/
│   ├── AIPopover.tsx             # Chat UI (messages, input, streaming)
│   ├── AreaSelector.tsx          # Screenshot selection tool
│   ├── ChatPicker.tsx            # "New Chat" picker on selection
│   └── SelectionLayer.tsx        # Text selection overlay
├── hooks/
│   └── useSelection.ts          # Selection & chat history state
├── lib/
│   └── gemini.ts                # Gemini client & model config
├── PDFViewer.tsx                 # Main viewer (tabs, pages, sidebar)
├── page.tsx                      # App entry point
├── layout.tsx                    # Root layout
└── globals.css                   # Global styles

MIT