#MoonBencode (Bencode Library for MoonBit)

#Features

• Robust Decoding: Safely parses i...e, <len>:<string>, l...e, and d...e into a MoonBit AST.
• Accurate Encoding: Encodes MoonBit AST back to strict Bencode Bytes with byte-for-byte fidelity.
• High Performance: Highly optimized array and byte sequence operations with zero dependencies.
• JSON Interoperability: Supports lossy/lossless conversion of Bencode AST to standard JSON, and parsing JSON back to a canonical, key-sorted Bencode AST.
• Path Lookup: Easily retrieves nested list/dictionary values by path.
• Torrent Info Hash: Built-in pure MoonBit SHA-1 algorithm to calculate the info_hash fingerprint of a torrent file.

#Installation & Dependency Setup

#1. Add Dependency to Project

moon add 2515050243qyf/moon_bencode

import {
  "2515050243qyf/moon_bencode" = "0.1.2"
}

#2. Import Package in Module

{
  "deps": {
    "2515050243qyf/moon_bencode/src/bencode": ""
  }
}

#Quick Start

///|
pub fn main raise {
  // Decode a Bencode string
  let val = @bencode.decode(b"d3:bar4:spam3:fooi42ee")
  println("Decoded: \{val}")
  // Output: BDict([(b"bar", BStr(b"spam")), (b"foo", BInt(42))])

  // Encode it back to Bytes
  let bytes = @bencode.encode(val)
  println("Encoded: \{bytes}")
  // Output: b"d3:bar4:spam3:fooi42ee"
}

#Advanced Features

#1. JSON Interoperability

///|
pub fn example_json(val : @bencode.BValue) raise {
  // Convert to Json
  let json_obj = val.to_json()
  println(json_obj.stringify())

  // Parse back to BValue
  let b_val = @bencode.BValue::from_json(json_obj)
}

#2. Path Lookup

///|
pub fn example_path(torrent : @bencode.BValue) {
  // Retrieve the nested 'name' field inside 'info'
  match torrent.get_path(["info", "name"]) {
    Some(BStr(name)) => println("Name: \{name}")
    _ => println("Not found")
  }
}

#3. Torrent Info Hash Calculation

///|
pub fn example_hash(torrent : @bencode.BValue) {
  match torrent.info_hash() {
    Some(hash_bytes) => println("Info Hash: \{hash_bytes}")
    None => println("Invalid torrent")
  }
}

#Data Types

• BInt(Int64): Bencode integers.
• BStr(Bytes): Bencode byte strings.
• BList(Array[BValue]): Bencode lists.
• BDict(Array[(Bytes, BValue)]): Bencode dictionaries (keys sorted lexicographically).

#CLI Commands

• Run syntax check: moon check --deny-warn
• Build project: moon build
• Run tests: moon test --deny-warn
• Verify code formatting: moon fmt --check

#License