📖 EBook-RS: Multi-Format Rust EBook Parser and Reader Engine (v0.12.0)

ebook-rs is a high-performance, 100% pure Rust parser and reader engine for EPUB 2, EPUB 3, MOBI, AZW3 (KF8), FB2 (FictionBook 2), KEPUB (Kobo EPUB), LIT (Microsoft Reader), CBZ (Comic Book ZIP), PDF, ODT, TXT, and MD formats, designed for full feature parity with epub.js and foliate-js, equipped with native AI/RAG document chunking, C FFI multi-language bindings, and Web Component support.

⚡ Feature Parity Matrix

📂 Format Support

Feature	🚀 `ebook-rs` (v0.12.0)	📦 `epub.js`	📖 `foliate-js`	🦀 `rbook`
EPUB 2 & 3 Support	✅ Full OPF + NCX/NAV	✅ Yes	✅ Yes	✅ Yes
EPUB 3 Fixed-Layout (FXL)	✅ 2-page spread renderer	✅ Yes	✅ Yes	❌ No
MOBI & AZW3 (KF8) Support	✅ Native PalmDOC LZ77	❌ No	✅ Yes	❌ No
FB2 (FictionBook 2) Support	✅ Native XML + xlink:href	❌ No	✅ Yes	❌ No
KEPUB (Kobo EPUB) Support	✅ Native	❌ No	✅ Yes	❌ No
LIT (Microsoft Reader) Support	✅ Native	❌ No	✅ Yes	❌ No
CBZ (Comic Book ZIP) Support	✅ Native ZIP Images	❌ No	✅ Yes	❌ No
PDF Support	✅ `pdf_oxide` parser	❌ No	❌ No	❌ No
ODT (OpenDocument Text)	✅ `office_oxide`	❌ No	❌ No	❌ No
TXT / Markdown Support	✅ Auto-reflow sections	❌ No	❌ No	❌ No
Auto Format Detection	✅ Magic-byte detection	❌ No	❌ No	❌ No

🧭 Navigation & Rendering

Feature	🚀 `ebook-rs` (v0.12.0)	📦 `epub.js`	📖 `foliate-js`	🦀 `rbook`
IDPF CFI Engine	✅ Parse / format / compare / range	✅ Yes	✅ Yes	✅ Yes
CFI DOM Resolver	✅ `cfi.resolve_dom_path(html)`	✅ Yes	✅ Yes	❌ No
Readium CFI Unified Locator	✅ Full model	✅ Yes	✅ Yes	❌ No
Location / Reading Progress	✅ `locations_from_sections()`	✅ Yes	✅ Yes	✅ Yes
SMIL Media Overlays (Sync)	✅ NPT clock parser	✅ Yes	✅ Yes	❌ No
EPUB NCX / NAV TOC Parsing	✅ Deep recursive nav tree	✅ Yes	✅ Yes	✅ Yes
RTL & CJK Vertical Writing	✅ `direction: rtl` + `vertical-rl`	✅ Yes	✅ Yes	❌ No
Viewport Meta Parsing	✅ Zero-alloc slice parse	✅ Yes	✅ Yes	❌ No
Reflow Paginator	✅ `ReflowPaginator::paginate_section`	✅ Yes	✅ Yes	❌ No
Custom Font Injection	✅ `@font-face` CSS injection	✅ Yes	✅ Yes	❌ No

🔍 Search, Analytics & AI RAG

Feature	🚀 `ebook-rs` (v0.12.0)	📦 `epub.js`	📖 `foliate-js`	🦀 `rbook`
AI & RAG Chunking Engine	✅ `to_rag_chunks()` + CFI citations	❌ No	❌ No	❌ No
Full-Text Search	✅ SIMD-accelerated	❌ No	✅ Basic	❌ No
Regex Search	✅ `regex_search`	❌ No	❌ No	❌ No
Search Context Snippets	✅ `<mark>` highlights + XSS guard	❌ No	✅ Yes	❌ No
Readium Search JSON Export	✅ Readium-compliant JSON	❌ No	✅ Yes	❌ No
NLP Reading Analytics	✅ Word count / reading time / complexity	❌ No	❌ No	❌ No
Auto Language Detection	✅ `detect_language` (`whatlang`)	❌ No	❌ No	❌ No

🌐 Interoperability & Web Component

Feature	🚀 `ebook-rs` (v0.12.0)	📦 `epub.js`	📖 `foliate-js`	🦀 `rbook`
C / Python / Node FFI Bindings	✅ `ebook_rs::ffi` C ABI	❌ No	❌ No	❌ No
Web Component Generator	✅ `<ebook-reader>` HTMLElement	❌ No	❌ No	❌ No
WASM Client SDK	✅ `WasmBook` WASM bindings	✅ Yes	✅ Yes	❌ No
W3C Web Annotation (JSON-LD)	✅ Full CRUD + `to_w3c_json`	❌ No	✅ Yes	❌ No
Readium WebPub Manifest Export	✅ `book.to_webpub_manifest()`	❌ No	✅ Yes	❌ No
OPDS 1.2 / 2.0 Catalog	✅ Atom XML + JSON parser	❌ No	❌ No	❌ No

🆕 What's New in v0.12.0

Native AI & RAG Document Chunking Engine (src/rag.rs):
- book.to_rag_chunks(&config) splits eBooks into AI-ready semantic chunks with Markdown heading hierarchy, token estimations, and exact epubcfi citation anchors for Vector DBs and LLM prompt ingestion.
C / Multi-Language FFI Bindings (src/ffi.rs):
- C-compatible ABI (#[unsafe(no_mangle)] extern "C") functions for zero-copy integration across Python (ctypes/pyo3), Node.js (ffi-napi), C/C++, Swift (iOS), Kotlin (Android), and Go.
Zero-Dependency <ebook-reader> Web Component (src/wasm.rs):
- WasmBook::get_custom_element_js() generates a standalone <ebook-reader> custom element for plug-and-play web reader integration in React, Vue, Svelte, and Next.js.
CJK Vertical Text & RTL Reading Modes (src/layout.rs):
- Added WritingMode enum (HorizontalLtr, HorizontalRtl, VerticalRl, VerticalLr) with dynamic CSS overrides for Arabic, Hebrew, Japanese, Chinese, and Korean vertical reading layout.
CLI Converter & RAG Commands (src/main.rs):
- ebook-rs convert <input> <output.epub> converts any supported format into valid EPUB 3 using UniversalEpub3Exporter.
- ebook-rs rag <input.epub> [max_tokens] generates JSON AI RAG chunks directly from the terminal.

🚀 Quick Start Examples

1. Basic Parsing & RAG Chunking (Rust)

use ebook_rs::{Book, RagChunkConfig};

fn main() -> Result<(), String> {
    let book = Book::from_file("book.epub")?;

    println!("Title: {}", book.metadata().title);
    println!("Language: {:?}", book.detect_language());

    // Generate AI / RAG document chunks with CFI citation anchors
    let config = RagChunkConfig {
        max_tokens: 512,
        overlap_tokens: 64,
        preserve_headings: true,
        ..Default::default()
    };
    let chunks = book.to_rag_chunks(&config);

    for chunk in chunks {
        println!("ID: {}", chunk.id);
        println!("CFI Anchor: {}", chunk.cfi);
        println!("Markdown: \n{}", chunk.markdown);
    }

    Ok(())
}

2. Multi-Format CLI Conversion & RAG Export

# Convert MOBI, PDF, FB2, or TXT into a valid EPUB 3 file
ebook-rs convert sample.mobi output.epub

# Export AI RAG chunks directly to JSON
ebook-rs convert book.epub chunks.json

# Stream JSON RAG chunks to stdout
ebook-rs rag book.epub 512

3. C / Python FFI API Integration

#include "ebook_rs.h"

int main() {
    uint8_t* buffer = load_file("book.epub", &len);
    CBookHandle book = ebook_rs_book_from_bytes(buffer, len);

    char* json_meta = ebook_rs_get_metadata_json(book);
    printf("Metadata: %s\n", json_meta);
    ebook_rs_string_free(json_meta);

    char* json_rag = ebook_rs_to_rag_chunks_json(book, 512);
    printf("RAG Chunks: %s\n", json_rag);
    ebook_rs_string_free(json_rag);

    ebook_rs_book_free(book);
    return 0;
}

📖 Documentation & Wiki

Detailed API documentation and integration guides are available in docs/API.md, API.md, and WIKI.md.

ebook-rs 0.12.1