Add parts of zxing library to generate qr codes

1 files changed, 322 insertions, 0 deletions

diff --git a/OpenPGP-Keychain/src/com/google/zxing/qrcode/decoder/DecodedBitStreamParser.java b/OpenPGP-Keychain/src/com/google/zxing/qrcode/decoder/DecodedBitStreamParser.java
new file mode 100644
index 000000000..ff374ac50
--- /dev/null
+++ b/OpenPGP-Keychain/src/com/google/zxing/qrcode/decoder/DecodedBitStreamParser.java
@@ -0,0 +1,322 @@
+/*
+ * Copyright 2007 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.qrcode.decoder;
+
+import com.google.zxing.FormatException;
+import com.google.zxing.common.BitSource;
+import com.google.zxing.common.CharacterSetECI;
+import com.google.zxing.common.DecoderResult;
+import com.google.zxing.common.StringUtils;
+
+import java.io.UnsupportedEncodingException;
+import java.util.Hashtable;
+import java.util.Vector;
+
+/**
+ * <p>QR Codes can encode text as bits in one of several modes, and can use multiple modes
+ * in one QR Code. This class decodes the bits back into text.</p>
+ *
+ * <p>See ISO 18004:2006, 6.4.3 - 6.4.7</p>
+ *
+ * @author Sean Owen
+ */
+final class DecodedBitStreamParser {
+
+  /**
+   * See ISO 18004:2006, 6.4.4 Table 5
+   */
+  private static final char[] ALPHANUMERIC_CHARS = {
+      '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B',
+      'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N',
+      'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
+      ' ', '$', '%', '*', '+', '-', '.', '/', ':'
+  };
+  private static final int GB2312_SUBSET = 1;
+
+  private DecodedBitStreamParser() {
+  }
+
+  static DecoderResult decode(byte[] bytes, Version version, ErrorCorrectionLevel ecLevel, Hashtable hints)
+      throws FormatException {
+    BitSource bits = new BitSource(bytes);
+    StringBuffer result = new StringBuffer(50);
+    CharacterSetECI currentCharacterSetECI = null;
+    boolean fc1InEffect = false;
+    Vector byteSegments = new Vector(1);
+    Mode mode;
+    do {
+      // While still another segment to read...
+      if (bits.available() < 4) {
+        // OK, assume we're done. Really, a TERMINATOR mode should have been recorded here
+        mode = Mode.TERMINATOR;
+      } else {
+        try {
+          mode = Mode.forBits(bits.readBits(4)); // mode is encoded by 4 bits
+        } catch (IllegalArgumentException iae) {
+          throw FormatException.getFormatInstance();
+        }
+      }
+      if (!mode.equals(Mode.TERMINATOR)) {
+        if (mode.equals(Mode.FNC1_FIRST_POSITION) || mode.equals(Mode.FNC1_SECOND_POSITION)) {
+          // We do little with FNC1 except alter the parsed result a bit according to the spec
+          fc1InEffect = true;
+        } else if (mode.equals(Mode.STRUCTURED_APPEND)) {
+          // not really supported; all we do is ignore it
+          // Read next 8 bits (symbol sequence #) and 8 bits (parity data), then continue
+          bits.readBits(16);
+        } else if (mode.equals(Mode.ECI)) {
+          // Count doesn't apply to ECI
+          int value = parseECIValue(bits);
+          currentCharacterSetECI = CharacterSetECI.getCharacterSetECIByValue(value);
+          if (currentCharacterSetECI == null) {
+            throw FormatException.getFormatInstance();
+          }
+        } else {
+          // First handle Hanzi mode which does not start with character count
+          if (mode.equals(Mode.HANZI)) {
+        		//chinese mode contains a sub set indicator right after mode indicator
+        		int subset = bits.readBits(4);
+        		int countHanzi = bits.readBits(mode.getCharacterCountBits(version));
+        		if (subset == GB2312_SUBSET) {
+        			decodeHanziSegment(bits, result, countHanzi);
+            }
+          } else {
+            // "Normal" QR code modes:
+            // How many characters will follow, encoded in this mode?
+            int count = bits.readBits(mode.getCharacterCountBits(version));
+            if (mode.equals(Mode.NUMERIC)) {
+              decodeNumericSegment(bits, result, count);
+            } else if (mode.equals(Mode.ALPHANUMERIC)) {
+              decodeAlphanumericSegment(bits, result, count, fc1InEffect);
+            } else if (mode.equals(Mode.BYTE)) {
+              decodeByteSegment(bits, result, count, currentCharacterSetECI, byteSegments, hints);
+            } else if (mode.equals(Mode.KANJI)) {
+              decodeKanjiSegment(bits, result, count);
+            } else {
+              throw FormatException.getFormatInstance();
+            }
+          }
+        }
+      }
+    } while (!mode.equals(Mode.TERMINATOR));
+
+    return new DecoderResult(bytes,
+                             result.toString(),
+                             byteSegments.isEmpty() ? null : byteSegments,
+                             ecLevel == null ? null : ecLevel.toString());
+  }
+
+  /**
+   * See specification GBT 18284-2000
+   */
+  private static void decodeHanziSegment(BitSource bits,
+                                         StringBuffer result,
+                                         int count) throws FormatException {
+    // Don't crash trying to read more bits than we have available.
+    if (count * 13 > bits.available()) {
+      throw FormatException.getFormatInstance();
+    }
+
+    // Each character will require 2 bytes. Read the characters as 2-byte pairs
+    // and decode as GB2312 afterwards
+    byte[] buffer = new byte[2 * count];
+    int offset = 0;
+    while (count > 0) {
+      // Each 13 bits encodes a 2-byte character
+      int twoBytes = bits.readBits(13);
+      int assembledTwoBytes = ((twoBytes / 0x060) << 8) | (twoBytes % 0x060);
+      if (assembledTwoBytes < 0x003BF) {
+        // In the 0xA1A1 to 0xAAFE range
+        assembledTwoBytes += 0x0A1A1;
+      } else {
+        // In the 0xB0A1 to 0xFAFE range
+        assembledTwoBytes += 0x0A6A1;
+      }
+      buffer[offset] = (byte) ((assembledTwoBytes >> 8) & 0xFF);
+      buffer[offset + 1] = (byte) (assembledTwoBytes & 0xFF);
+      offset += 2;
+      count--;
+    }
+
+    try {
+      result.append(new String(buffer, StringUtils.GB2312));
+    } catch (UnsupportedEncodingException uee) {
+      throw FormatException.getFormatInstance();
+    }
+  }
+
+  private static void decodeKanjiSegment(BitSource bits,
+                                         StringBuffer result,
+                                         int count) throws FormatException {
+    // Don't crash trying to read more bits than we have available.
+    if (count * 13 > bits.available()) {
+      throw FormatException.getFormatInstance();
+    }
+
+    // Each character will require 2 bytes. Read the characters as 2-byte pairs
+    // and decode as Shift_JIS afterwards
+    byte[] buffer = new byte[2 * count];
+    int offset = 0;
+    while (count > 0) {
+      // Each 13 bits encodes a 2-byte character
+      int twoBytes = bits.readBits(13);
+      int assembledTwoBytes = ((twoBytes / 0x0C0) << 8) | (twoBytes % 0x0C0);
+      if (assembledTwoBytes < 0x01F00) {
+        // In the 0x8140 to 0x9FFC range
+        assembledTwoBytes += 0x08140;
+      } else {
+        // In the 0xE040 to 0xEBBF range
+        assembledTwoBytes += 0x0C140;
+      }
+      buffer[offset] = (byte) (assembledTwoBytes >> 8);
+      buffer[offset + 1] = (byte) assembledTwoBytes;
+      offset += 2;
+      count--;
+    }
+    // Shift_JIS may not be supported in some environments:
+    try {
+      result.append(new String(buffer, StringUtils.SHIFT_JIS));
+    } catch (UnsupportedEncodingException uee) {
+      throw FormatException.getFormatInstance();
+    }
+  }
+
+  private static void decodeByteSegment(BitSource bits,
+                                        StringBuffer result,
+                                        int count,
+                                        CharacterSetECI currentCharacterSetECI,
+                                        Vector byteSegments,
+                                        Hashtable hints) throws FormatException {
+    // Don't crash trying to read more bits than we have available.
+    if (count << 3 > bits.available()) {
+      throw FormatException.getFormatInstance();
+    }
+
+    byte[] readBytes = new byte[count];
+    for (int i = 0; i < count; i++) {
+      readBytes[i] = (byte) bits.readBits(8);
+    }
+    String encoding;
+    if (currentCharacterSetECI == null) {
+    // The spec isn't clear on this mode; see
+    // section 6.4.5: t does not say which encoding to assuming
+    // upon decoding. I have seen ISO-8859-1 used as well as
+    // Shift_JIS -- without anything like an ECI designator to
+    // give a hint.
+      encoding = StringUtils.guessEncoding(readBytes, hints);
+    } else {
+      encoding = currentCharacterSetECI.getEncodingName();
+    }
+    try {
+      result.append(new String(readBytes, encoding));
+    } catch (UnsupportedEncodingException uce) {
+      throw FormatException.getFormatInstance();
+    }
+    byteSegments.addElement(readBytes);
+  }
+
+  private static char toAlphaNumericChar(int value) throws FormatException {
+    if (value >= ALPHANUMERIC_CHARS.length) {
+      throw FormatException.getFormatInstance();
+    }
+    return ALPHANUMERIC_CHARS[value];
+  }
+
+  private static void decodeAlphanumericSegment(BitSource bits,
+                                                StringBuffer result,
+                                                int count,
+                                                boolean fc1InEffect) throws FormatException {
+    // Read two characters at a time
+    int start = result.length();
+    while (count > 1) {
+      int nextTwoCharsBits = bits.readBits(11);
+      result.append(toAlphaNumericChar(nextTwoCharsBits / 45));
+      result.append(toAlphaNumericChar(nextTwoCharsBits % 45));
+      count -= 2;
+    }
+    if (count == 1) {
+      // special case: one character left
+      result.append(toAlphaNumericChar(bits.readBits(6)));
+    }
+    // See section 6.4.8.1, 6.4.8.2
+    if (fc1InEffect) {
+      // We need to massage the result a bit if in an FNC1 mode:
+      for (int i = start; i < result.length(); i++) {
+        if (result.charAt(i) == '%') {
+          if (i < result.length() - 1 && result.charAt(i + 1) == '%') {
+            // %% is rendered as %
+            result.deleteCharAt(i + 1);
+          } else {
+            // In alpha mode, % should be converted to FNC1 separator 0x1D
+            result.setCharAt(i, (char) 0x1D);
+          }
+        }
+      }
+    }
+  }
+
+  private static void decodeNumericSegment(BitSource bits,
+                                           StringBuffer result,
+                                           int count) throws FormatException {
+    // Read three digits at a time
+    while (count >= 3) {
+      // Each 10 bits encodes three digits
+      int threeDigitsBits = bits.readBits(10);
+      if (threeDigitsBits >= 1000) {
+        throw FormatException.getFormatInstance();
+      }
+      result.append(toAlphaNumericChar(threeDigitsBits / 100));
+      result.append(toAlphaNumericChar((threeDigitsBits / 10) % 10));
+      result.append(toAlphaNumericChar(threeDigitsBits % 10));
+      count -= 3;
+    }
+    if (count == 2) {
+      // Two digits left over to read, encoded in 7 bits
+      int twoDigitsBits = bits.readBits(7);
+      if (twoDigitsBits >= 100) {
+        throw FormatException.getFormatInstance();
+      }
+      result.append(toAlphaNumericChar(twoDigitsBits / 10));
+      result.append(toAlphaNumericChar(twoDigitsBits % 10));
+    } else if (count == 1) {
+      // One digit left over to read
+      int digitBits = bits.readBits(4);
+      if (digitBits >= 10) {
+        throw FormatException.getFormatInstance();
+      }
+      result.append(toAlphaNumericChar(digitBits));
+    }
+  }
+
+  private static int parseECIValue(BitSource bits) {
+    int firstByte = bits.readBits(8);
+    if ((firstByte & 0x80) == 0) {
+      // just one byte
+      return firstByte & 0x7F;
+    } else if ((firstByte & 0xC0) == 0x80) {
+      // two bytes
+      int secondByte = bits.readBits(8);
+      return ((firstByte & 0x3F) << 8) | secondByte;
+    } else if ((firstByte & 0xE0) == 0xC0) {
+      // three bytes
+      int secondThirdBytes = bits.readBits(16);
+      return ((firstByte & 0x1F) << 16) | secondThirdBytes;
+    }
+    throw new IllegalArgumentException("Bad ECI bits starting with byte " + firstByte);
+  }
+
+}