spica

import { min } from './alias'; const ASCII = [...Array(1 << 8)].reduce<string>((acc, _, i) => acc + String.fromCharCode(i), ''); const HUFFMAN_CODES = new Uint32Array([ 0x1ff8, 0x7fffd8, 0xfffffe2, 0xfffffe3, 0xfffffe4, 0xfffffe5, 0xfffffe6, 0xfffffe7, 0xfffffe8, 0xffffea, 0x3ffffffc, 0xfffffe9, 0xfffffea, 0x3ffffffd, 0xfffffeb, 0xfffffec, 0xfffffed, 0xfffffee, 0xfffffef, 0xffffff0, 0xffffff1, 0xffffff2, 0x3ffffffe, 0xffffff3, 0xffffff4, 0xffffff5, 0xffffff6, 0xffffff7, 0xffffff8, 0xffffff9, 0xffffffa, 0xffffffb, 0x14, 0x3f8, 0x3f9, 0xffa, 0x1ff9, 0x15, 0xf8, 0x7fa, 0x3fa, 0x3fb, 0xf9, 0x7fb, 0xfa, 0x16, 0x17, 0x18, 0x0, 0x1, 0x2, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x5c, 0xfb, 0x7ffc, 0x20, 0xffb, 0x3fc, 0x1ffa, 0x21, 0x5d, 0x5e, 0x5f, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0xfc, 0x73, 0xfd, 0x1ffb, 0x7fff0, 0x1ffc, 0x3ffc, 0x22, 0x7ffd, 0x3, 0x23, 0x4, 0x24, 0x5, 0x25, 0x26, 0x27, 0x6, 0x74, 0x75, 0x28, 0x29, 0x2a, 0x7, 0x2b, 0x76, 0x2c, 0x8, 0x9, 0x2d, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7ffe, 0x7fc, 0x3ffd, 0x1ffd, 0xffffffc, 0xfffe6, 0x3fffd2, 0xfffe7, 0xfffe8, 0x3fffd3, 0x3fffd4, 0x3fffd5, 0x7fffd9, 0x3fffd6, 0x7fffda, 0x7fffdb, 0x7fffdc, 0x7fffdd, 0x7fffde, 0xffffeb, 0x7fffdf, 0xffffec, 0xffffed, 0x3fffd7, 0x7fffe0, 0xffffee, 0x7fffe1, 0x7fffe2, 0x7fffe3, 0x7fffe4, 0x1fffdc, 0x3fffd8, 0x7fffe5, 0x3fffd9, 0x7fffe6, 0x7fffe7, 0xffffef, 0x3fffda, 0x1fffdd, 0xfffe9, 0x3fffdb, 0x3fffdc, 0x7fffe8, 0x7fffe9, 0x1fffde, 0x7fffea, 0x3fffdd, 0x3fffde, 0xfffff0, 0x1fffdf, 0x3fffdf, 0x7fffeb, 0x7fffec, 0x1fffe0, 0x1fffe1, 0x3fffe0, 0x1fffe2, 0x7fffed, 0x3fffe1, 0x7fffee, 0x7fffef, 0xfffea, 0x3fffe2, 0x3fffe3, 0x3fffe4, 0x7ffff0, 0x3fffe5, 0x3fffe6, 0x7ffff1, 0x3ffffe0, 0x3ffffe1, 0xfffeb, 0x7fff1, 0x3fffe7, 0x7ffff2, 0x3fffe8, 0x1ffffec, 0x3ffffe2, 0x3ffffe3, 0x3ffffe4, 0x7ffffde, 0x7ffffdf, 0x3ffffe5, 0xfffff1, 0x1ffffed, 0x7fff2, 0x1fffe3, 0x3ffffe6, 0x7ffffe0, 0x7ffffe1, 0x3ffffe7, 0x7ffffe2, 0xfffff2, 0x1fffe4, 0x1fffe5, 0x3ffffe8, 0x3ffffe9, 0xffffffd, 0x7ffffe3, 0x7ffffe4, 0x7ffffe5, 0xfffec, 0xfffff3, 0xfffed, 0x1fffe6, 0x3fffe9, 0x1fffe7, 0x1fffe8, 0x7ffff3, 0x3fffea, 0x3fffeb, 0x1ffffee, 0x1ffffef, 0xfffff4, 0xfffff5, 0x3ffffea, 0x7ffff4, 0x3ffffeb, 0x7ffffe6, 0x3ffffec, 0x3ffffed, 0x7ffffe7, 0x7ffffe8, 0x7ffffe9, 0x7ffffea, 0x7ffffeb, 0xffffffe, 0x7ffffec, 0x7ffffed, 0x7ffffee, 0x7ffffef, 0x7fffff0, 0x3ffffee, 0x3fffffff // EOS ]); const HUFFMAN_CODE_LENGTHS = new Uint8Array([ 13, 23, 28, 28, 28, 28, 28, 28, 28, 24, 30, 28, 28, 30, 28, 28, 28, 28, 28, 28, 28, 28, 30, 28, 28, 28, 28, 28, 28, 28, 28, 28, 6, 10, 10, 12, 13, 6, 8, 11, 10, 10, 8, 11, 8, 6, 6, 6, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 7, 8, 15, 6, 12, 10, 13, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 7, 8, 13, 19, 13, 14, 6, 15, 5, 6, 5, 6, 5, 6, 6, 6, 5, 7, 7, 6, 6, 6, 5, 6, 7, 6, 5, 5, 6, 7, 7, 7, 7, 7, 15, 11, 14, 13, 28, 20, 22, 20, 20, 22, 22, 22, 23, 22, 23, 23, 23, 23, 23, 24, 23, 24, 24, 22, 23, 24, 23, 23, 23, 23, 21, 22, 23, 22, 23, 23, 24, 22, 21, 20, 22, 22, 23, 23, 21, 23, 22, 22, 24, 21, 22, 23, 23, 21, 21, 22, 21, 23, 22, 23, 23, 20, 22, 22, 22, 23, 22, 22, 23, 26, 26, 20, 19, 22, 23, 22, 25, 26, 26, 26, 27, 27, 26, 24, 25, 19, 21, 26, 27, 27, 26, 27, 24, 21, 21, 26, 26, 28, 27, 27, 27, 20, 24, 20, 21, 22, 21, 21, 23, 22, 22, 25, 25, 24, 24, 26, 23, 26, 27, 26, 26, 27, 27, 27, 27, 27, 28, 27, 27, 27, 27, 27, 26, 30 // EOS ]); //[HUFFMAN_CODES[50], HUFFMAN_CODES[114]] = [HUFFMAN_CODES[114], HUFFMAN_CODES[50]]; //[HUFFMAN_CODE_LENGTHS[50], HUFFMAN_CODE_LENGTHS[114]] = [HUFFMAN_CODE_LENGTHS[114], HUFFMAN_CODE_LENGTHS[50]]; //[HUFFMAN_CODES[49], HUFFMAN_CODES[110]] = [HUFFMAN_CODES[110], HUFFMAN_CODES[49]]; //[HUFFMAN_CODE_LENGTHS[49], HUFFMAN_CODE_LENGTHS[110]] = [HUFFMAN_CODE_LENGTHS[110], HUFFMAN_CODE_LENGTHS[49]]; //[HUFFMAN_CODES[48], HUFFMAN_CODES[108]] = [HUFFMAN_CODES[108], HUFFMAN_CODES[48]]; //[HUFFMAN_CODE_LENGTHS[48], HUFFMAN_CODE_LENGTHS[108]] = [HUFFMAN_CODE_LENGTHS[108], HUFFMAN_CODE_LENGTHS[48]]; assert(HUFFMAN_CODES.length === HUFFMAN_CODE_LENGTHS.length); const EOS = ''; const MIN = 5; type Tree = [(string | Tree)?, (string | Tree)?]; const HUFFMAN_TABLE: (string | Tree)[] = []; HUFFMAN_CODES.forEach((_, i) => { const code = HUFFMAN_CODES[i]; let count = HUFFMAN_CODE_LENGTHS[i] - MIN; assert(count >= 0); if (count === 0) { HUFFMAN_TABLE[code] = ASCII[i]; return; } let node = (HUFFMAN_TABLE[code >> count] as Tree) ??= []; assert(typeof node === 'object'); for (; count !== 0; --count) { const b = code & 1 << count - 1 && 1; if (count === 1) { assert(node[b] === undefined); node[b] = ASCII[i] ?? ''; } else { node = (node[b] as Tree) ??= []; assert(typeof node === 'object'); } } }); export function encode(input: string, stats?: { length: number; }): string { stats && (stats.length = 0); let output = ''; let buffer = 0; let count = 0; for (let i = 0; i < input.length; ++i) { const code = input.charCodeAt(i); const hcode = HUFFMAN_CODES[code]; let hlen = HUFFMAN_CODE_LENGTHS[code]; while (hlen !== 0) { assert(count < 8); const cnt = min(hlen, 8 - count); assert(cnt > 0); buffer |= (hcode >>> hlen - cnt & (1 << cnt) - 1) << 8 - count - cnt; assert(buffer >>> 8 === 0); count += cnt; assert(count <= 8); hlen -= cnt; assert(hlen >= 0); if (count !== 8) continue; output += ASCII[buffer]; stats && (stats.length += count); buffer = 0; count = 0; } } if (count !== 0) { assert(count < 8); output += ASCII[buffer | 0xff >>> count]; stats && (stats.length += count); } return output; } export function decode(input: string): string { let output = ''; let buffer = 0; let count = 0; let node: Tree[0]; for (let i = 0; i < input.length; ++i) { buffer <<= 8; buffer |= input.charCodeAt(i); count += 8; assert(count <= 32); while (count !== 0) { if (node === undefined) { if (count < MIN) break; node = HUFFMAN_TABLE[buffer >> count - MIN & (1 << MIN) - 1]; if (typeof node === 'string') { output += node; node = undefined; } count -= MIN; } else { assert(node = node as Tree); const b = buffer & 1 << count - 1 && 1; node = node[b]; if (node === EOS) return output; if (typeof node === 'string') { output += node; node = undefined; } --count; } } } return output; }