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/*
* Copyright 2010 ZXing authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.zxing.oned;
import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.common.BitMatrix;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Map;
/**
* This object renders a CODE128 code as a {@link BitMatrix}.
*
* @author [email protected] (Erik Barbara)
*/
public final class Code128Writer extends OneDimensionalCodeWriter {
private static final int CODE_START_A = 103;
private static final int CODE_START_B = 104;
private static final int CODE_START_C = 105;
private static final int CODE_CODE_A = 101;
private static final int CODE_CODE_B = 100;
private static final int CODE_CODE_C = 99;
private static final int CODE_STOP = 106;
// Dummy characters used to specify control characters in input
private static final char ESCAPE_FNC_1 = '\u00f1';
private static final char ESCAPE_FNC_2 = '\u00f2';
private static final char ESCAPE_FNC_3 = '\u00f3';
private static final char ESCAPE_FNC_4 = '\u00f4';
private static final int CODE_FNC_1 = 102; // Code A, Code B, Code C
private static final int CODE_FNC_2 = 97; // Code A, Code B
private static final int CODE_FNC_3 = 96; // Code A, Code B
private static final int CODE_FNC_4_A = 101; // Code A
private static final int CODE_FNC_4_B = 100; // Code B
// Results of minimal lookahead for code C
private enum CType {
UNCODABLE,
ONE_DIGIT,
TWO_DIGITS,
FNC_1
}
@Override
protected Collection getSupportedWriteFormats() {
return Collections.singleton(BarcodeFormat.CODE_128);
}
@Override
public boolean[] encode(String contents) {
return encode(contents, null);
}
@Override
public boolean[] encode(String contents, Map hints) {
int forcedCodeSet = check(contents, hints);
boolean hasCompactionHint = hints != null && hints.containsKey(EncodeHintType.CODE128_COMPACT) &&
Boolean.parseBoolean(hints.get(EncodeHintType.CODE128_COMPACT).toString());
return hasCompactionHint ? new MinimalEncoder().encode(contents) : encodeFast(contents, forcedCodeSet);
}
private static int check(String contents, Map hints) {
// Check for forced code set hint.
int forcedCodeSet = -1;
if (hints != null && hints.containsKey(EncodeHintType.FORCE_CODE_SET)) {
String codeSetHint = hints.get(EncodeHintType.FORCE_CODE_SET).toString();
switch (codeSetHint) {
case "A":
forcedCodeSet = CODE_CODE_A;
break;
case "B":
forcedCodeSet = CODE_CODE_B;
break;
case "C":
forcedCodeSet = CODE_CODE_C;
break;
default:
throw new IllegalArgumentException("Unsupported code set hint: " + codeSetHint);
}
}
// Check content
int length = contents.length();
for (int i = 0; i < length; i++) {
char c = contents.charAt(i);
// check for non ascii characters that are not special GS1 characters
switch (c) {
// special function characters
case ESCAPE_FNC_1:
case ESCAPE_FNC_2:
case ESCAPE_FNC_3:
case ESCAPE_FNC_4:
break;
// non ascii characters
default:
if (c > 127) {
// no full Latin-1 character set available at the moment
// shift and manual code change are not supported
throw new IllegalArgumentException("Bad character in input: ASCII value=" + (int) c);
}
}
// check characters for compatibility with forced code set
switch (forcedCodeSet) {
case CODE_CODE_A:
// allows no ascii above 95 (no lower caps, no special symbols)
if (c > 95 && c <= 127) {
throw new IllegalArgumentException("Bad character in input for forced code set A: ASCII value=" + (int) c);
}
break;
case CODE_CODE_B:
// allows no ascii below 32 (terminal symbols)
if (c < 32) {
throw new IllegalArgumentException("Bad character in input for forced code set B: ASCII value=" + (int) c);
}
break;
case CODE_CODE_C:
// allows only numbers and no FNC 2/3/4
if (c < 48 || (c > 57 && c <= 127) || c == ESCAPE_FNC_2 || c == ESCAPE_FNC_3 || c == ESCAPE_FNC_4) {
throw new IllegalArgumentException("Bad character in input for forced code set C: ASCII value=" + (int) c);
}
break;
}
}
return forcedCodeSet;
}
private static boolean[] encodeFast(String contents, int forcedCodeSet) {
int length = contents.length();
Collection patterns = new ArrayList<>(); // temporary storage for patterns
int checkSum = 0;
int checkWeight = 1;
int codeSet = 0; // selected code (CODE_CODE_B or CODE_CODE_C)
int position = 0; // position in contents
while (position < length) {
//Select code to use
int newCodeSet;
if (forcedCodeSet == -1) {
newCodeSet = chooseCode(contents, position, codeSet);
} else {
newCodeSet = forcedCodeSet;
}
//Get the pattern index
int patternIndex;
if (newCodeSet == codeSet) {
// Encode the current character
// First handle escapes
switch (contents.charAt(position)) {
case ESCAPE_FNC_1:
patternIndex = CODE_FNC_1;
break;
case ESCAPE_FNC_2:
patternIndex = CODE_FNC_2;
break;
case ESCAPE_FNC_3:
patternIndex = CODE_FNC_3;
break;
case ESCAPE_FNC_4:
if (codeSet == CODE_CODE_A) {
patternIndex = CODE_FNC_4_A;
} else {
patternIndex = CODE_FNC_4_B;
}
break;
default:
// Then handle normal characters otherwise
switch (codeSet) {
case CODE_CODE_A:
patternIndex = contents.charAt(position) - ' ';
if (patternIndex < 0) {
// everything below a space character comes behind the underscore in the code patterns table
patternIndex += '`';
}
break;
case CODE_CODE_B:
patternIndex = contents.charAt(position) - ' ';
break;
default:
// CODE_CODE_C
if (position + 1 == length) {
// this is the last character, but the encoding is C, which always encodes two characers
throw new IllegalArgumentException("Bad number of characters for digit only encoding.");
}
patternIndex = Integer.parseInt(contents.substring(position, position + 2));
position++; // Also incremented below
break;
}
}
position++;
} else {
// Should we change the current code?
// Do we have a code set?
if (codeSet == 0) {
// No, we don't have a code set
switch (newCodeSet) {
case CODE_CODE_A:
patternIndex = CODE_START_A;
break;
case CODE_CODE_B:
patternIndex = CODE_START_B;
break;
default:
patternIndex = CODE_START_C;
break;
}
} else {
// Yes, we have a code set
patternIndex = newCodeSet;
}
codeSet = newCodeSet;
}
// Get the pattern
patterns.add(Code128Reader.CODE_PATTERNS[patternIndex]);
// Compute checksum
checkSum += patternIndex * checkWeight;
if (position != 0) {
checkWeight++;
}
}
return produceResult(patterns, checkSum);
}
static boolean[] produceResult(Collection patterns, int checkSum) {
// Compute and append checksum
checkSum %= 103;
if (checkSum < 0) {
throw new IllegalArgumentException("Unable to compute a valid input checksum");
}
patterns.add(Code128Reader.CODE_PATTERNS[checkSum]);
// Append stop code
patterns.add(Code128Reader.CODE_PATTERNS[CODE_STOP]);
// Compute code width
int codeWidth = 0;
for (int[] pattern : patterns) {
for (int width : pattern) {
codeWidth += width;
}
}
// Compute result
boolean[] result = new boolean[codeWidth];
int pos = 0;
for (int[] pattern : patterns) {
pos += appendPattern(result, pos, pattern, true);
}
return result;
}
private static CType findCType(CharSequence value, int start) {
int last = value.length();
if (start >= last) {
return CType.UNCODABLE;
}
char c = value.charAt(start);
if (c == ESCAPE_FNC_1) {
return CType.FNC_1;
}
if (c < '0' || c > '9') {
return CType.UNCODABLE;
}
if (start + 1 >= last) {
return CType.ONE_DIGIT;
}
c = value.charAt(start + 1);
if (c < '0' || c > '9') {
return CType.ONE_DIGIT;
}
return CType.TWO_DIGITS;
}
private static int chooseCode(CharSequence value, int start, int oldCode) {
CType lookahead = findCType(value, start);
if (lookahead == CType.ONE_DIGIT) {
if (oldCode == CODE_CODE_A) {
return CODE_CODE_A;
}
return CODE_CODE_B;
}
if (lookahead == CType.UNCODABLE) {
if (start < value.length()) {
char c = value.charAt(start);
if (c < ' ' || (oldCode == CODE_CODE_A && (c < '`' || (c >= ESCAPE_FNC_1 && c <= ESCAPE_FNC_4)))) {
// can continue in code A, encodes ASCII 0 to 95 or FNC1 to FNC4
return CODE_CODE_A;
}
}
return CODE_CODE_B; // no choice
}
if (oldCode == CODE_CODE_A && lookahead == CType.FNC_1) {
return CODE_CODE_A;
}
if (oldCode == CODE_CODE_C) { // can continue in code C
return CODE_CODE_C;
}
if (oldCode == CODE_CODE_B) {
if (lookahead == CType.FNC_1) {
return CODE_CODE_B; // can continue in code B
}
// Seen two consecutive digits, see what follows
lookahead = findCType(value, start + 2);
if (lookahead == CType.UNCODABLE || lookahead == CType.ONE_DIGIT) {
return CODE_CODE_B; // not worth switching now
}
if (lookahead == CType.FNC_1) { // two digits, then FNC_1...
lookahead = findCType(value, start + 3);
if (lookahead == CType.TWO_DIGITS) { // then two more digits, switch
return CODE_CODE_C;
} else {
return CODE_CODE_B; // otherwise not worth switching
}
}
// At this point, there are at least 4 consecutive digits.
// Look ahead to choose whether to switch now or on the next round.
int index = start + 4;
while ((lookahead = findCType(value, index)) == CType.TWO_DIGITS) {
index += 2;
}
if (lookahead == CType.ONE_DIGIT) { // odd number of digits, switch later
return CODE_CODE_B;
}
return CODE_CODE_C; // even number of digits, switch now
}
// Here oldCode == 0, which means we are choosing the initial code
if (lookahead == CType.FNC_1) { // ignore FNC_1
lookahead = findCType(value, start + 1);
}
if (lookahead == CType.TWO_DIGITS) { // at least two digits, start in code C
return CODE_CODE_C;
}
return CODE_CODE_B;
}
/**
* Encodes minimally using Divide-And-Conquer with Memoization
**/
private static final class MinimalEncoder {
private enum Charset { A, B, C, NONE }
private enum Latch { A, B, C, SHIFT, NONE }
static final String A = " !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_\u0000\u0001\u0002" +
"\u0003\u0004\u0005\u0006\u0007\u0008\u0009\n\u000B\u000C\r\u000E\u000F\u0010\u0011" +
"\u0012\u0013\u0014\u0015\u0016\u0017\u0018\u0019\u001A\u001B\u001C\u001D\u001E\u001F" +
"\u00FF";
static final String B = " !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqr" +
"stuvwxyz{|}~\u007F\u00FF";
private static final int CODE_SHIFT = 98;
private int[][] memoizedCost;
private Latch[][] minPath;
private boolean[] encode(String contents) {
memoizedCost = new int[4][contents.length()];
minPath = new Latch[4][contents.length()];
encode(contents, Charset.NONE, 0);
Collection patterns = new ArrayList<>();
int[] checkSum = new int[] {0};
int[] checkWeight = new int[] {1};
int length = contents.length();
Charset charset = Charset.NONE;
for (int i = 0; i < length; i++) {
Latch latch = minPath[charset.ordinal()][i];
switch (latch) {
case A:
charset = Charset.A;
addPattern(patterns, i == 0 ? CODE_START_A : CODE_CODE_A, checkSum, checkWeight, i);
break;
case B:
charset = Charset.B;
addPattern(patterns, i == 0 ? CODE_START_B : CODE_CODE_B, checkSum, checkWeight, i);
break;
case C:
charset = Charset.C;
addPattern(patterns, i == 0 ? CODE_START_C : CODE_CODE_C, checkSum, checkWeight, i);
break;
case SHIFT:
addPattern(patterns, CODE_SHIFT, checkSum, checkWeight, i);
break;
}
if (charset == Charset.C) {
if (contents.charAt(i) == ESCAPE_FNC_1) {
addPattern(patterns, CODE_FNC_1, checkSum, checkWeight, i);
} else {
addPattern(patterns, Integer.parseInt(contents.substring(i, i + 2)), checkSum, checkWeight, i);
assert i + 1 < length; //the algorithm never leads to a single trailing digit in character set C
if (i + 1 < length) {
i++;
}
}
} else { // charset A or B
int patternIndex;
switch (contents.charAt(i)) {
case ESCAPE_FNC_1:
patternIndex = CODE_FNC_1;
break;
case ESCAPE_FNC_2:
patternIndex = CODE_FNC_2;
break;
case ESCAPE_FNC_3:
patternIndex = CODE_FNC_3;
break;
case ESCAPE_FNC_4:
if (charset == Charset.A && latch != Latch.SHIFT ||
charset == Charset.B && latch == Latch.SHIFT) {
patternIndex = CODE_FNC_4_A;
} else {
patternIndex = CODE_FNC_4_B;
}
break;
default:
patternIndex = contents.charAt(i) - ' ';
}
if ((charset == Charset.A && latch != Latch.SHIFT ||
charset == Charset.B && latch == Latch.SHIFT) &&
patternIndex < 0) {
patternIndex += '`';
}
addPattern(patterns, patternIndex, checkSum, checkWeight, i);
}
}
memoizedCost = null;
minPath = null;
return produceResult(patterns, checkSum[0]);
}
private static void addPattern(Collection patterns,
int patternIndex,
int[] checkSum,
int[] checkWeight,
int position) {
patterns.add(Code128Reader.CODE_PATTERNS[patternIndex]);
if (position != 0) {
checkWeight[0]++;
}
checkSum[0] += patternIndex * checkWeight[0];
}
private static boolean isDigit(char c) {
return c >= '0' && c <= '9';
}
private boolean canEncode(CharSequence contents, Charset charset,int position) {
char c = contents.charAt(position);
switch (charset) {
case A: return c == ESCAPE_FNC_1 ||
c == ESCAPE_FNC_2 ||
c == ESCAPE_FNC_3 ||
c == ESCAPE_FNC_4 ||
A.indexOf(c) >= 0;
case B: return c == ESCAPE_FNC_1 ||
c == ESCAPE_FNC_2 ||
c == ESCAPE_FNC_3 ||
c == ESCAPE_FNC_4 ||
B.indexOf(c) >= 0;
case C: return c == ESCAPE_FNC_1 ||
(position + 1 < contents.length() &&
isDigit(c) &&
isDigit(contents.charAt(position + 1)));
default: return false;
}
}
/**
* Encode the string starting at position position starting with the character set charset
**/
private int encode(CharSequence contents, Charset charset, int position) {
assert position < contents.length();
int mCost = memoizedCost[charset.ordinal()][position];
if (mCost > 0) {
return mCost;
}
int minCost = Integer.MAX_VALUE;
Latch minLatch = Latch.NONE;
boolean atEnd = position + 1 >= contents.length();
Charset[] sets = new Charset[] { Charset.A, Charset.B };
for (int i = 0; i <= 1; i++) {
if (canEncode(contents, sets[i], position)) {
int cost = 1;
Latch latch = Latch.NONE;
if (charset != sets[i]) {
cost++;
latch = Latch.valueOf(sets[i].toString());
}
if (!atEnd) {
cost += encode(contents, sets[i], position + 1);
}
if (cost < minCost) {
minCost = cost;
minLatch = latch;
}
cost = 1;
if (charset == sets[(i + 1) % 2]) {
cost++;
latch = Latch.SHIFT;
if (!atEnd) {
cost += encode(contents, charset, position + 1);
}
if (cost < minCost) {
minCost = cost;
minLatch = latch;
}
}
}
}
if (canEncode(contents, Charset.C, position)) {
int cost = 1;
Latch latch = Latch.NONE;
if (charset != Charset.C) {
cost++;
latch = Latch.C;
}
int advance = contents.charAt(position) == ESCAPE_FNC_1 ? 1 : 2;
if (position + advance < contents.length()) {
cost += encode(contents, Charset.C, position + advance);
}
if (cost < minCost) {
minCost = cost;
minLatch = latch;
}
}
if (minCost == Integer.MAX_VALUE) {
throw new IllegalArgumentException("Bad character in input: ASCII value=" + (int) contents.charAt(position));
}
memoizedCost[charset.ordinal()][position] = minCost;
minPath[charset.ordinal()][position] = minLatch;
return minCost;
}
}
}
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