export namespace Base58 {
    // @ts-ignore: decorator
    @lazy
      const ALPHABET = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";
  
    // @ts-ignore: decorator
    @lazy
      const BASE = 58;
    
    // @ts-ignore: decorator
    @lazy
      const BASE_MAP = StaticArray.fromArray<u8>([255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,0,1,2,3,4,5,6,7,8,255,255,255,255,255,255,255,9,10,11,12,13,14,15,16,255,17,18,19,20,21,255,22,23,24,25,26,27,28,29,30,31,32,255,255,255,255,255,255,33,34,35,36,37,38,39,40,41,42,43,255,44,45,46,47,48,49,50,51,52,53,54,55,56,57,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255]);
  
    /**
      * Encode Uint8Array as a base58 string.
      * @param bytes Byte array of type Uint8Array.
      * @example
      * ```ts
      * const contractId = System.getContractId();
      * System.log("contractId: " + Base58.encode(contractId));
      * ```
      */
    export function encode(source: Uint8Array): string {
      // Code converted from:
      // https://github.com/cryptocoinjs/base-x/blob/master/index.js
      const iFACTOR = 2; // TODO: Calculate precise value to avoid overallocating
      
      const LEADER = ALPHABET.charAt(0);
  
      // Skip & count leading zeroes.
      let zeroes = 0;
      let length = 0;
      let pbegin = 0;
      let pend = source.length;
  
      while (pbegin != pend && source[pbegin] == 0) {
        pbegin++;
        zeroes++;
      }
  
      // Allocate enough space in big-endian base58 representation.
      let size = ((pend - pbegin) * iFACTOR + 1) >>> 0;
      let b58 = new Uint8Array(size);
  
      // Process the bytes.
      while (pbegin != pend) {
        let carry = i32(source[pbegin]);
  
        // Apply "b58 = b58 * 256 + ch".
        let i = 0;
        for (
          let it = size - 1;
          (carry != 0 || i < length) && it != -1;
          it--, i++
        ) {
          carry += (256 * b58[it]) >>> 0;
          b58[it] = carry % BASE >>> 0;
          carry = (carry / BASE) >>> 0;
        }
  
        assert(carry == 0, "Non-zero carry");
        length = i;
        pbegin++;
      }
  
      // Skip leading zeroes in base58 result.
      let it = size - length;
      while (it != size && b58[it] == 0) {
        it++;
      }
  
      // Translate the result into a string.
      let str = LEADER.repeat(zeroes);
      for (; it < size; ++it) str += ALPHABET.charAt(b58[it]);
  
      return str;
    }
  
    /**
      * Decode a base58 string into aUint8Array
      * @param string base58 encoded string
      * @example
      * ```ts
      * const from = Base58.decode("1DQzuCcTKacbs9GGScRTU1Hc8BsyARTPqe");
      * ```
      */
    export function decode(string: string): Uint8Array {
      const buffer = decodeUnsafe(string);
      if (buffer) {
        return buffer;
      }
      throw new Error("Non-base58 character");
    }
  
    function decodeUnsafe(source: string): Uint8Array {
      if (source.length == 0) {
        return new Uint8Array(0);
      }
      const LEADER = ALPHABET.charAt(0);
      const FACTOR = 1; // no floating point operations allowed so round up
    
      let psz = 0;
      // Skip leading spaces.
      while (source.charAt(psz) == " ") {
        psz++;
      }
    
      // Skip and count leading '1's.
      let length = 0;
    
      while (source.charAt(psz) == LEADER) {
        psz++;
      }
    
      // Allocate enough space in big-endian base256 representation.
      let size = i32((source.length - psz) * FACTOR + 1) >>> 0; // log(58) / log(256), rounded up.
      let b256 = new Uint8Array(size - 1);
    
      // Process the characters.
      while (source.charAt(psz)) {
        // Decode character
        let bmIdx = source.charCodeAt(psz);
    
        if (bmIdx < 0) break;
        let carry = i32(BASE_MAP[bmIdx]);
    
        // Invalid character
        if (carry == 255) {
          break;
        }
        let i = 0;
        for (
          let it = size - 2;
          (carry != 0 || i < length) && it != -1;
          it--, i++
        ) {
          carry += (BASE * b256[it]) >>> 0;
          b256[it] = carry % 256 >>> 0;
          carry = (carry / 256) >>> 0;
        }
        if (carry != 0) {
          throw new Error("Non-zero carry");
        }
        length = i;
        psz++;
      }
      // Skip trailing spaces.
      while (source.charAt(psz) == " ") {
        psz++;
      }
    
      // Skip leading zeroes in b256.
      let i = 0;
      while (b256[i] == 0) {
        i++;
      }
      i--; // keep the leading zero since that marked ed25519 (won't work with secp256k1)
    
      return <Uint8Array>b256.slice(i);
    }
  }