EPUBReaderSwiftUI

A SwiftUI‑first component for rendering EPUB books.

📦 Overview

EPUBReaderSwiftUI enables you to display .epub files within a SwiftUI view or container.
It supports the essential EPUB workflow: file selection, unpacking, and rendering of chapters/HTML content, while using a SwiftUI‑friendly interface.

✅ Features

• SwiftUI view (EPUBReaderSwiftUI) that can be integrated into your view hierarchy.
• Supports loading local EPUB files via URL.
• Renders content via WKWebView (or equivalent) inside SwiftUI.
• Navigation across chapters, table of contents support.
• Customisation points: theming, font size, paging/navigation.
• Bookmark / reading‑progress support (if implemented).
• Compatibility with modern Swift / SwiftUI toolchain.

🧭 Getting Started

Installation

Add EPUBReaderSwiftUI as a Swift Package in Xcode:

File → Add Packages… → `https://github.com/jtCodes/EPUBReaderSwiftUI.git`

Alternatively, integrate manually by copying the Sources/EPUBReaderSwiftUI folder.

Usage

import SwiftUI
import EPUBReaderSwiftUI
import ReadiumShared

struct ContentView: View {
    @State private var showReader = false
    @State private var savedLocator: Locator?
    @State private var savedPreferences = ReadingPreferences()
    @State private var epubURL: URL?
    @State private var isDownloading = false
    @State private var errorMessage: String?

    var body: some View {
        VStack {
            if isDownloading {
                ProgressView("Downloading EPUB...")
            } else {
                Button("Open EPUB") {
                    Task {
                        isDownloading = true
                        errorMessage = nil
                        
                        do {
                            // Option 1: Download from URL
                            epubURL = try await EPUBDownloader.downloadEPUB(from: "https://www.gutenberg.org/ebooks/9662.epub3.images")
                            
                            // Option 2: Or use local file
                            // epubURL = Bundle.main.url(forResource: "republic", withExtension: "epub")
                            
                            showReader = true
                        } catch {
                            errorMessage = "Failed to load EPUB: \(error.localizedDescription)"
                        }
                        
                        isDownloading = false
                    }
                }
                
                if let errorMessage = errorMessage {
                    Text(errorMessage)
                        .foregroundColor(.red)
                        .padding()
                }
            }
        }
        .fullScreenCover(isPresented: $showReader) {
            if let url = epubURL {
                EPUBReaderView(
                    url: url,
                    initialLocator: savedLocator,
                    initialPreferences: savedPreferences
                ) { locator, preferences in
                    savedLocator = locator
                    savedPreferences = preferences
                    showReader = false
                }
            }
        }
    }
}

Customisation

You can configure reader options (font size, theme) via EPUBReaderViewConfiguration (if provided).
You can also observe reading progress or chapter changes via published properties / delegate callbacks.

🔧 How it works (at a high level)

1. The EPUB file is unzipped into a temporary directory.
2. The OPF file (manifest/spine) is parsed to discover chapters, metadata and Table of Contents.
3. A WKWebView inside SwiftUI is used to display the HTML content of each chapter.
4. Navigation controls allow moving between chapters or pages.
5. State management handles current chapter, progress, bookmarks.

📚 Supported EPUB Features

• Standard EPUB 2/EPUB 3 packages (ZIP‑based).
• Basic HTML + CSS rendering via WebKit.
• Table of Contents.
• Local images/fonts inside the EPUB.

⚠️ Limitations & Known Issues

• Does not support advanced EPUB features such as media overlays (audio syncing), fixed‑layout books, or interactive content (unless explicitly added).
• Performance may degrade for very large books or very high font sizes — advisable to test on real devices.
• UI for bookmarks, highlights, annotations may not be included out‑of‑the‑box (you may need to extend).
• SwiftUI integration means there may be some bridging to UIKit/WebKit under the hood.

📖 License

MIT (or whichever license specified in the repository).
See LICENSE for details.

🤝 Contributing

Contributions, bug reports and feature requests are welcome!
Please open an issue or PR describing the improvement, and follow the code style (SwiftLint, SwiftFormat) as used in the project.

👤 Author

Created by jtCodes — thank you for sharing your work.

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Enjoy reading!