import BitArray from '../common/BitArray' ; import DecodeHintType from '../DecodeHintType' ; import Result from '../Result' ; import OneDReader from './OneDReader' ; import NotFoundException from '../NotFoundException' ; import FormatException from '../FormatException' ; import { int } from '../../customTypings' ; author dswitkin google author Sean Owen
 *  author alasdair google export default abstract class AbstractUPCEANReader extends OneDReader { private static MAX_AVG_VARIANCE = 0.48 ; private static MAX_INDIVIDUAL_VARIANCE = 0.7 ; /**
     * Start/end guard pattern.
     */ public static START_END_PATTERN : Int32Array = Int32Array . from ( [ 1 , 1 , 1 ] ) ; /**
     * Pattern marking the middle of a UPC/EAN pattern, separating the two halves.
     */ public static MIDDLE_PATTERN : Int32Array = Int32Array . from ( [ 1 , 1 , 1 , 1 , 1 ] ) ; /**
     * end guard pattern.
     */ public static END_PATTERN : Int32Array = Int32Array . from ( [ 1 , 1 , 1 , 1 , 1 , 1 ] ) ; /**
     * "Odd", or "L" patterns used to encode UPC/EAN digits.
     */ public static L_PATTERNS : Int32Array [ ] = [ Int32Array . from ( [ 3 , 2 , 1 , 1 ] ) , Int32Array . from ( [ 2 , 2 , 2 , 1 ] ) , Int32Array . from ( [ 2 , 1 , 2 , 2 ] ) , Int32Array . from ( [ 1 , 4 , 1 , 1 ] ) , Int32Array . from ( [ 1 , 1 , 3 , 2 ] ) , Int32Array . from ( [ 1 , 2 , 3 , 1 ] ) , Int32Array . from ( [ 1 , 1 , 1 , 4 ] ) , Int32Array . from ( [ 1 , 3 , 1 , 2 ] ) , Int32Array . from ( [ 1 , 2 , 1 , 3 ] ) , Int32Array . from ( [ 3 , 1 , 1 , 2 ] ) , ] ; /**
     * As above but also including the "even", or "G" patterns used to encode UPC/EAN digits.
     */ public static L_AND_G_PATTERNS : Int32Array [ ] ; protected decodeRowStringBuffer = '' ; static findStartGuardPattern ( row ) { let foundStart = false ; let startRange ; let nextStart = 0 ; let counters = Int32Array . from ( [ 0 , 0 , 0 ] ) ; while ( ! foundStart ) { counters = Int32Array . from ( [ 0 , 0 , 0 ] ) ; startRange = AbstractUPCEANReader . findGuardPattern ( row , nextStart , false , this . START_END_PATTERN , counters ) ; let start = startRange [ 0 ] ; nextStart = startRange [ 1 ] ; let quietStart = start - ( nextStart - start ) ; if ( quietStart >= 0 ) { foundStart = row . isRange ( quietStart , start , false ) ; } } return startRange ; } public abstract decodeRow ( rowNumber , row , hints ? ) ; static checkChecksum ( s ) { return AbstractUPCEANReader . checkStandardUPCEANChecksum ( s ) ; } static checkStandardUPCEANChecksum ( s ) { let length = s . length ; if ( length === 0 ) return false ; let check = parseInt ( s . charAt ( length - 1 ) , 10 ) ; return AbstractUPCEANReader . getStandardUPCEANChecksum ( s . substring ( 0 , length - 1 ) ) === check ; } static getStandardUPCEANChecksum ( s ) { let length = s . length ; let sum = 0 ; for ( let i = length - 1 ; i >= 0 ; i -= 2 ) { let digit = s . charAt ( i ) . charCodeAt ( 0 ) - '0' . charCodeAt ( 0 ) ; if ( digit < 0 || digit > 9 ) { throw new FormatException ( ) ; } sum += digit ; } sum *= 3 ; for ( let i = length - 2 ; i >= 0 ; i -= 2 ) { let digit = s . charAt ( i ) . charCodeAt ( 0 ) - '0' . charCodeAt ( 0 ) ; if ( digit < 0 || digit > 9 ) { throw new FormatException ( ) ; } sum += digit ; } return ( 1000 - sum ) % 10 ; } static decodeEnd ( row , endStart ) { return AbstractUPCEANReader . findGuardPattern ( row , endStart , false , AbstractUPCEANReader . START_END_PATTERN , new Int32Array ( AbstractUPCEANReader . START_END_PATTERN . length ) . fill ( 0 ) ) ; } throws static findGuardPatternWithoutCounters ( row , rowOffset , whiteFirst , pattern ) { return this . findGuardPattern ( row , rowOffset , whiteFirst , pattern , new Int32Array ( pattern . length ) ) ; } param row param rowOffset param whiteFirst param pattern param counters return throws static findGuardPattern ( row , rowOffset , whiteFirst , pattern , counters ) { let width = row . getSize ( ) ; rowOffset = whiteFirst ? row . getNextUnset ( rowOffset ) : row . getNextSet ( rowOffset ) ; let counterPosition = 0 ; let patternStart = rowOffset ; let patternLength = pattern . length ; let isWhite = whiteFirst ; for ( let x = rowOffset ; x < width ; x ++ ) { if ( row . get ( x ) !== isWhite ) { counters [ counterPosition ] ++ ; } else { if ( counterPosition === patternLength - 1 ) { if ( OneDReader . patternMatchVariance ( counters , pattern , AbstractUPCEANReader . MAX_INDIVIDUAL_VARIANCE ) < AbstractUPCEANReader . MAX_AVG_VARIANCE ) { return Int32Array . from ( [ patternStart , x ] ) ; } patternStart += counters [ 0 ] + counters [ 1 ] ; let slice = counters . slice ( 2 , counters . length - 1 ) ; for ( let i = 0 ; i < counterPosition - 1 ; i ++ ) { counters [ i ] = slice [ i ] ; } counters [ counterPosition - 1 ] = 0 ; counters [ counterPosition ] = 0 ; counterPosition -- ; } else { counterPosition ++ ; } counters [ counterPosition ] = 1 ; isWhite = ! isWhite ; } } throw new NotFoundException ( ) ; } static decodeDigit ( row , counters , rowOffset , patterns ) { this . recordPattern ( row , rowOffset , counters ) ; let bestVariance = this . MAX_AVG_VARIANCE ; let bestMatch = - 1 ; let max = patterns . length ; for ( let i = 0 ; i < max ; i ++ ) { let pattern = patterns [ i ] ; let variance = OneDReader . patternMatchVariance ( counters , pattern , AbstractUPCEANReader . MAX_INDIVIDUAL_VARIANCE ) ; if ( variance < bestVariance ) { bestVariance = variance ; bestMatch = i ; } } if ( bestMatch >= 0 ) { return bestMatch ; } else { throw new NotFoundException ( ) ; } } return public abstract getBarcodeFormat ( ) ; param row param startRange param resultString StringBuilder to append decoded chars to
     *  return throws public abstract decodeMiddle ( row , startRange , resultString ) ; }