import { BinaryStream } from "../../save-file/binary" ; type HuffmanEncoding = string | [ HuffmanEncoding , HuffmanEncoding ] | [ ] ; const HUFFMAN = [ [ [ [ [ "w" , "u" ] , [ [ "8" , [ "y" , [ "5" , [ "j" , [ ] ] ] ] ] , "h" ] ] , [ "s" , [ [ "2" , "n" ] , "x" ] ] ] , [ [ [ "c" , [ "k" , "f" ] ] , "b" ] , [ [ "t" , "m" ] , [ "9" , "7" ] ] ] ] , [ " " , [ [ [ [ "e" , "d" ] , "p" ] , [ "g" , [ [ [ "z" , "q" ] , "3" ] , [ "v" , "6" ] ] ] ] , [ [ "r" , "l" ] , [ "a" , [ [ "1" , [ "4" , "0" ] ] , [ "i" , "o" ] ] ] ] ] ] ] ; const WRITE_LOOKUP = new Map < string , string > ( ) ; function populateLookups ( encoding , path = "" ) { if ( ! encoding ) return ; if ( Array . isArray ( encoding ) ) { populateLookups ( encoding [ 0 ] , path + "0" ) ; populateLookups ( encoding [ 1 ] , path + "1" ) ; } else { WRITE_LOOKUP . set ( encoding , path ) ; } } populateLookups ( HUFFMAN ) ; export function decodeHuffman ( stream , nbChars ) { let result = "" ; for ( let i = 0 ; i < nbChars ; i ++ ) { let char = HUFFMAN ; while ( Array . isArray ( char ) ) { const next = Number ( stream . read ( 1 ) ) ; char = char [ next ] ; } result += char ; } return result ; } export function encodeHuffman ( value ) { return value . split ( "" ) . map ( ( char ) => { const encoded = WRITE_LOOKUP . get ( char ) ; if ( typeof encoded === "undefined" ) { throw new Error ( `Failed to huffman encode ${ value }.` ) ; } return encoded ; } ) . join ( "" ) ; }