Zipc – ZIP archive and deflate codec for MoonBit

Zipc is an in-memory ZIP archive and deflate compression codec for MoonBit, ported from the original OCaml zipc library.

This library provides:

• Deflate compression/decompression with CRC-32 and Adler-32 checksums
• ZIP archive reading/writing with support for stored and deflate compression
• High-quality test suite ensuring correctness and compatibility

Features

• Pure MoonBit implementation with no external dependencies
• Support for deflate and stored (no compression) formats
• CRC-32 and Adler-32 checksum validation
• In-memory ZIP archive manipulation
• Comprehensive test coverage

Installation

Add this to your moon.pkg.json:

{
  "import": ["bobzhang/zipc"]
}

Quick Start

// Create a ZIP archive
let archive = @zipc.empty()

// Create file data (stored format - no compression)
match @zipc.stored_of_binary_string("Hello, World!") {
  @deflate.Ok(file_data) => {
    // Create a member
    match @zipc.member_make("hello.txt", @zipc.MemberKind::File(file_data)) {
      @deflate.Ok(member) => {
        // Add to archive
        let archive = @zipc.add(member, archive)
        
        // Encode to bytes
        match @zipc.to_binary_string(archive) {
          @deflate.Ok(zip_bytes) => println("ZIP archive created successfully!")
          @deflate.Err(error) => println("Error encoding archive: \{error}")
        }
      }
      @deflate.Err(error) => println("Error creating member: \{error}")
    }
  }
  @deflate.Err(error) => println("Error creating file data: \{error}")
}

Current Status

This is a work-in-progress port of the OCaml zipc library to MoonBit. Currently implemented:

✅ Working Features

• CRC-32 checksums - Full implementation with lookup table
• Adler-32 checksums - Complete implementation for zlib format
• ZIP archive structure - Types and basic operations
• Stored format files - Uncompressed file support
• Deflate compression/decompression - Uncompressed deflate blocks
• Full ZIP parsing - Read existing ZIP files with complete format support
• ZIP encoding - Write complete ZIP archives with proper headers
• Directory entries - Full directory support with proper attributes
• Archive operations - Add, remove, find members with comprehensive API
• Mixed compression - Stored and deflate files in same archive
• Comprehensive tests - Extensive test suite with 6 passing test modules

🚧 Advanced Features (Future)

• Fixed/Dynamic Huffman compression - Full deflate algorithm implementation
• Zlib format support - Deflate with zlib headers and checksums
• ZIP64 support - Large file and archive support
• Advanced ZIP features - Extended attributes, encryption support

📋 API Compatibility

The API closely follows the original OCaml zipc library structure:

• Result[T, E] type for error handling
• Functional programming style with immutable data structures
• Comprehensive type safety

License

ISC License - same as the original OCaml zipc library.