package filename import (	"encoding/base64"	"sync" 	"github.com/klauspost/compress/huff0") // encodeURL is base64 url encoding values.const encodeURL = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_" // decodeMap will return x = decodeMap[encodeURL[byte(x)]] - 1 if x >= 0 and x < 64, otherwise -1 is returned.var decodeMap [256]byte // maxLength is the maximum length that will be attempted to be compressed.const maxLength = 256 var (	initOnce sync.Once // Used to control init of tables. 	encTables     [64]*huff0.Scratch // Encoders.	encTableLocks [64]sync.Mutex     // Temporary locks for encoders since they are stateful.	decTables     [64]*huff0.Decoder // Stateless decoders.) const (	tableUncompressed = 0 	tableSCSU      = 59	tableSCSUPlain = 60	tableRLE       = 61	tableCustom    = 62	tableReserved  = 63) // predefined tables as base64 URL encoded string.var tablesData = [64]string{	// Uncompressed	tableUncompressed: "",	// ncw home directory	1: "MRDIEtAAMAzDMAzDSjX_ybu0w97bb-L3b2mR-rUl5LXW3lZII43kIDMzM1NXu3okgQs=",	// ncw images	2: "IhDIAEAA______-Pou_4Sf5z-uS-39MVWjullFLKM7EBECs=",	// ncw Google Drive:	3: "JxDQAIIBMDMzMwOzbv7nJJCyd_m_9D2llCarnQX33nvvlFKEhUxAAQ==",	// Hex	4: "ExDoSTD___-tfXfhJ0hKSkryTxU=",	// Base64	5: "JRDIcQf_______8PgIiIiIgINkggARHlkQwSSCCBxHFYINHdfXI=",	// Hex plus a bit...	6: "E5CxwAHm9sYcAlmWZVvMHA4Y5jw=",	// Hex, upper case letters.	7: "FICxgAMMAGC3YwMthe3DWM_wDAAQ", 	// Special tables:	// SCSU and a fairly generic table:	tableSCSU: "UxAgZmEB-RYPU8hrnAk6uMgpTNQMB5MGRBx0D3T0JjyUyY-yOi5CoGgktbAktSh7d36HtPTFu7SXJ7FYw_AYmA74ZH2vWgc8O6Z5jLnWnsFqU_4B",	// SCSU with no table...	tableSCSUPlain: "",	// Compressed data has its own table.	tableCustom: "",	// Reserved for extension.	tableReserved: "",} func initCoders() {	initOnce.Do(func() {		// Init base 64 decoder.		for i, v := range encodeURL {			decodeMap[v] = byte(i) + 1		} 		// Initialize encoders and decoders.		for i, dataString := range tablesData {			if len(dataString) == 0 {				continue			}			data, err := base64.URLEncoding.DecodeString(dataString)			if err != nil {				panic(err)			}			s, _, err := huff0.ReadTable(data, nil)			if err != nil {				panic(err)			} 			// We want to save at least len(in) >> 5			s.WantLogLess = 5			s.Reuse = huff0.ReusePolicyMust			encTables[i] = s			decTables[i] = s.Decoder()		}		// Add custom table type.		var s huff0.Scratch		s.Reuse = huff0.ReusePolicyNone		encTables[tableCustom] = &s		decTables[tableCustom] = nil	})}