am e3338420: Merge "Introduce BinaryDictionaryHeader to access binary dictionary header."

* commit 'e3338420f6a0c0491d55af0536123f71959d9f80':
  Introduce BinaryDictionaryHeader to access binary dictionary header.

18 files changed, 424 insertions, 233 deletions

diff --git a/native/jni/Android.mk b/native/jni/Android.mk
index 7ca405752..9718cf5fb 100644
--- a/native/jni/Android.mk
+++ b/native/jni/Android.mk
@@ -55,7 +55,9 @@ LATIN_IME_CORE_SRC_FILES := \
         dic_nodes_cache.cpp) \
     $(addprefix suggest/core/dictionary/, \
         bigram_dictionary.cpp \
-        binary_dictionary_format.cpp \
+        binary_dictionary_format_utils.cpp \
+        binary_dictionary_header.cpp \
+        binary_dictionary_header_reading_utils.cpp \
         byte_array_utils.cpp \
         dictionary.cpp \
         digraph_utils.cpp) \
diff --git a/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp b/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
index f60793733..8490e32bc 100644
--- a/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
+++ b/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
@@ -27,7 +27,7 @@
 #include "jni.h"
 #include "jni_common.h"
 #include "obsolete/correction.h"
-#include "suggest/core/dictionary/binary_dictionary_format.h"
+#include "suggest/core/dictionary/binary_dictionary_format_utils.h"
 #include "suggest/core/dictionary/binary_dictionary_info.h"
 #include "suggest/core/dictionary/dictionary.h"
 #include "suggest/core/suggest_options.h"
diff --git a/native/jni/src/suggest/core/dictionary/binary_dictionary_format.cpp b/native/jni/src/suggest/core/dictionary/binary_dictionary_format_utils.cpp
index 50e0211d7..737df63c7 100644
--- a/native/jni/src/suggest/core/dictionary/binary_dictionary_format.cpp
+++ b/native/jni/src/suggest/core/dictionary/binary_dictionary_format_utils.cpp
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-#include "suggest/core/dictionary/binary_dictionary_format.h"
+#include "suggest/core/dictionary/binary_dictionary_format_utils.h"
 
 namespace latinime {
 
@@ -31,7 +31,6 @@ const int BinaryDictionaryFormat::DICTIONARY_MINIMUM_SIZE = 4;
 // then options that must be 0. Hence the first 32-bits of the format are always as follow
 // and it's okay to consider them a magic number as a whole.
 const uint32_t BinaryDictionaryFormat::FORMAT_VERSION_1_MAGIC_NUMBER = 0x78B10100;
-const int BinaryDictionaryFormat::FORMAT_VERSION_1_HEADER_SIZE = 5;
 
 // The versions of Latin IME that only handle format version 1 only test for the magic
 // number, so we had to change it so that version 2 files would be rejected by older
@@ -39,9 +38,6 @@ const int BinaryDictionaryFormat::FORMAT_VERSION_1_HEADER_SIZE = 5;
 const uint32_t BinaryDictionaryFormat::FORMAT_VERSION_2_MAGIC_NUMBER = 0x9BC13AFE;
 // Magic number (4 bytes), version (2 bytes), options (2 bytes), header size (4 bytes) = 12
 const int BinaryDictionaryFormat::FORMAT_VERSION_2_MINIMUM_SIZE = 12;
-const int BinaryDictionaryFormat::VERSION_2_MAGIC_NUMBER_SIZE = 4;
-const int BinaryDictionaryFormat::VERSION_2_DICTIONARY_VERSION_SIZE = 2;
-const int BinaryDictionaryFormat::VERSION_2_DICTIONARY_FLAG_SIZE = 2;
 
 /* static */ BinaryDictionaryFormat::FORMAT_VERSION BinaryDictionaryFormat::detectFormatVersion(
         const uint8_t *const dict, const int dictSize) {
diff --git a/native/jni/src/suggest/core/dictionary/binary_dictionary_format.h b/native/jni/src/suggest/core/dictionary/binary_dictionary_format_utils.h
index 3aa1662da..c0fd56111 100644
--- a/native/jni/src/suggest/core/dictionary/binary_dictionary_format.h
+++ b/native/jni/src/suggest/core/dictionary/binary_dictionary_format_utils.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef LATINIME_BINARY_DICTIONARY_FORMAT_H
-#define LATINIME_BINARY_DICTIONARY_FORMAT_H
+#ifndef LATINIME_BINARY_DICTIONARY_FORMAT_UTILS_H
+#define LATINIME_BINARY_DICTIONARY_FORMAT_UTILS_H
 
 #include <stdint.h>
 
@@ -42,30 +42,13 @@ class BinaryDictionaryFormat {
 
     static FORMAT_VERSION detectFormatVersion(const uint8_t *const dict, const int dictSize);
 
-    static AK_FORCE_INLINE int getHeaderSize(
-            const uint8_t *const dict, const FORMAT_VERSION format) {
-        switch (format) {
-        case VERSION_1:
-            return FORMAT_VERSION_1_HEADER_SIZE;
-        case VERSION_2:
-            // See the format of the header in the comment in detectFormat() above
-            return ByteArrayUtils::readUint32(dict, 8);
-        default:
-            return S_INT_MAX;
-        }
-    }
-
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(BinaryDictionaryFormat);
 
     static const int DICTIONARY_MINIMUM_SIZE;
     static const uint32_t FORMAT_VERSION_1_MAGIC_NUMBER;
-    static const int FORMAT_VERSION_1_HEADER_SIZE;
     static const uint32_t FORMAT_VERSION_2_MAGIC_NUMBER;
     static const int FORMAT_VERSION_2_MINIMUM_SIZE;
-    static const int VERSION_2_MAGIC_NUMBER_SIZE;
-    static const int VERSION_2_DICTIONARY_VERSION_SIZE ;
-    static const int VERSION_2_DICTIONARY_FLAG_SIZE;
 };
 } // namespace latinime
-#endif /* LATINIME_BINARY_DICTIONARY_FORMAT_H */
+#endif /* LATINIME_BINARY_DICTIONARY_FORMAT_UTILS_H */
diff --git a/native/jni/src/suggest/core/dictionary/binary_dictionary_header.cpp b/native/jni/src/suggest/core/dictionary/binary_dictionary_header.cpp
new file mode 100644
index 000000000..04bb81f71
--- /dev/null
+++ b/native/jni/src/suggest/core/dictionary/binary_dictionary_header.cpp
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2013, The Android Open Source Project
+ *
+ * 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.
+ */
+
+#include "suggest/core/dictionary/binary_dictionary_header.h"
+
+#include "defines.h"
+#include "suggest/core/dictionary/binary_dictionary_info.h"
+
+namespace latinime {
+
+const char *const BinaryDictionaryHeader::MULTIPLE_WORDS_DEMOTION_RATE_KEY =
+        "MULTIPLE_WORDS_DEMOTION_RATE";
+const float BinaryDictionaryHeader::DEFAULT_MULTI_WORD_COST_MULTIPLIER = 1.0f;
+const float BinaryDictionaryHeader::MULTI_WORD_COST_MULTIPLIER_SCALE = 100.0f;
+
+BinaryDictionaryHeader::BinaryDictionaryHeader(
+        const BinaryDictionaryInfo *const binaryDictionaryInfo)
+        : mBinaryDictionaryInfo(binaryDictionaryInfo),
+          mDictionaryFlags(BinaryDictionaryHeaderReader::getFlags(binaryDictionaryInfo)),
+          mSize(BinaryDictionaryHeaderReader::getHeaderSize(binaryDictionaryInfo)),
+          mMultiWordCostMultiplier(readMultiWordCostMultiplier()) {}
+
+float BinaryDictionaryHeader::readMultiWordCostMultiplier() const {
+    const int headerValue = BinaryDictionaryHeaderReader::readHeaderValueInt(
+            mBinaryDictionaryInfo, MULTIPLE_WORDS_DEMOTION_RATE_KEY);
+    if (headerValue == S_INT_MIN) {
+        // not found
+        return DEFAULT_MULTI_WORD_COST_MULTIPLIER;
+    }
+    if (headerValue <= 0) {
+        return static_cast<float>(MAX_VALUE_FOR_WEIGHTING);
+    }
+    return MULTI_WORD_COST_MULTIPLIER_SCALE / static_cast<float>(headerValue);
+}
+
+} // namespace latinime
diff --git a/native/jni/src/suggest/core/dictionary/binary_dictionary_header.h b/native/jni/src/suggest/core/dictionary/binary_dictionary_header.h
new file mode 100644
index 000000000..9db000362
--- /dev/null
+++ b/native/jni/src/suggest/core/dictionary/binary_dictionary_header.h
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2013, The Android Open Source Project
+ *
+ * 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.
+ */
+
+#ifndef LATINIME_BINARY_DICTIONARY_HEADER_H
+#define LATINIME_BINARY_DICTIONARY_HEADER_H
+
+#include "defines.h"
+#include "suggest/core/dictionary/binary_dictionary_header_reading_utils.h"
+
+namespace latinime {
+
+class BinaryDictionaryInfo;
+
+/**
+ * This class abstracts dictionary header structures and provide interface to access dictionary
+ * header information.
+ */
+class BinaryDictionaryHeader {
+ public:
+    explicit BinaryDictionaryHeader(const BinaryDictionaryInfo *const binaryDictionaryInfo);
+
+    AK_FORCE_INLINE int getSize() const {
+        return mSize;
+    }
+
+    AK_FORCE_INLINE bool supportsDynamicUpdate() const {
+        return BinaryDictionaryHeaderReader::supportsDynamicUpdate(mDictionaryFlags);
+    }
+
+    AK_FORCE_INLINE bool requiresGermanUmlautProcessing() const {
+        return BinaryDictionaryHeaderReader::requiresGermanUmlautProcessing(mDictionaryFlags);
+    }
+
+    AK_FORCE_INLINE bool requiresFrenchLigatureProcessing() const {
+        return BinaryDictionaryHeaderReader::requiresFrenchLigatureProcessing(mDictionaryFlags);
+    }
+
+    AK_FORCE_INLINE float getMultiWordCostMultiplier() const {
+        return mMultiWordCostMultiplier;
+    }
+
+ private:
+    DISALLOW_COPY_AND_ASSIGN(BinaryDictionaryHeader);
+
+    static const char *const MULTIPLE_WORDS_DEMOTION_RATE_KEY;
+    static const float DEFAULT_MULTI_WORD_COST_MULTIPLIER;
+    static const float MULTI_WORD_COST_MULTIPLIER_SCALE;
+
+    const BinaryDictionaryInfo *const mBinaryDictionaryInfo;
+    const BinaryDictionaryHeaderReader::DictionaryFlags mDictionaryFlags;
+    const int mSize;
+    const float mMultiWordCostMultiplier;
+
+    float readMultiWordCostMultiplier() const;
+};
+} // namespace latinime
+#endif // LATINIME_BINARY_DICTIONARY_HEADER_H
diff --git a/native/jni/src/suggest/core/dictionary/binary_dictionary_header_reading_utils.cpp b/native/jni/src/suggest/core/dictionary/binary_dictionary_header_reading_utils.cpp
new file mode 100644
index 000000000..c09a78f03
--- /dev/null
+++ b/native/jni/src/suggest/core/dictionary/binary_dictionary_header_reading_utils.cpp
@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2013, The Android Open Source Project
+ *
+ * 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.
+ */
+
+#include "suggest/core/dictionary/binary_dictionary_header_reading_utils.h"
+
+#include <cctype>
+#include <cstdlib>
+
+#include "defines.h"
+#include "suggest/core/dictionary/binary_dictionary_info.h"
+
+namespace latinime {
+
+const int BinaryDictionaryHeaderReader::MAX_OPTION_KEY_LENGTH = 256;
+
+const int BinaryDictionaryHeaderReader::FORMAT_VERSION_1_HEADER_SIZE = 5;
+
+const int BinaryDictionaryHeaderReader::VERSION_2_MAGIC_NUMBER_SIZE = 4;
+const int BinaryDictionaryHeaderReader::VERSION_2_DICTIONARY_VERSION_SIZE = 2;
+const int BinaryDictionaryHeaderReader::VERSION_2_DICTIONARY_FLAG_SIZE = 2;
+const int BinaryDictionaryHeaderReader::VERSION_2_DICTIONARY_HEADER_SIZE_SIZE = 4;
+
+const BinaryDictionaryHeaderReader::DictionaryFlags BinaryDictionaryHeaderReader::NO_FLAGS = 0;
+// Flags for special processing
+// Those *must* match the flags in makedict (BinaryDictInputOutput#*_PROCESSING_FLAG) or
+// something very bad (like, the apocalypse) will happen. Please update both at the same time.
+const BinaryDictionaryHeaderReader::DictionaryFlags
+        BinaryDictionaryHeaderReader::GERMAN_UMLAUT_PROCESSING_FLAG = 0x1;
+const BinaryDictionaryHeaderReader::DictionaryFlags
+        BinaryDictionaryHeaderReader::SUPPORTS_DYNAMIC_UPDATE_FLAG = 0x2;
+const BinaryDictionaryHeaderReader::DictionaryFlags
+        BinaryDictionaryHeaderReader::FRENCH_LIGATURE_PROCESSING_FLAG = 0x4;
+
+/* static */ int BinaryDictionaryHeaderReader::getHeaderSize(
+        const BinaryDictionaryInfo *const binaryDictionaryInfo) {
+    switch (binaryDictionaryInfo->getFormat()) {
+        case BinaryDictionaryFormat::VERSION_1:
+            return FORMAT_VERSION_1_HEADER_SIZE;
+        case BinaryDictionaryFormat::VERSION_2:
+            // See the format of the header in the comment in
+            // BinaryDictionaryFormatUtils::detectFormatVersion()
+            return ByteArrayUtils::readUint32(binaryDictionaryInfo->getDictBuf(),
+                    VERSION_2_MAGIC_NUMBER_SIZE + VERSION_2_DICTIONARY_VERSION_SIZE
+                            + VERSION_2_DICTIONARY_FLAG_SIZE);
+        default:
+            return S_INT_MAX;
+    }
+}
+
+/* static */ BinaryDictionaryHeaderReader::DictionaryFlags BinaryDictionaryHeaderReader::getFlags(
+        const BinaryDictionaryInfo *const binaryDictionaryInfo) {
+    switch (binaryDictionaryInfo->getFormat()) {
+        case BinaryDictionaryFormat::VERSION_1:
+            return NO_FLAGS;
+        case BinaryDictionaryFormat::VERSION_2:
+            return ByteArrayUtils::readUint16(binaryDictionaryInfo->getDictBuf(),
+                    VERSION_2_MAGIC_NUMBER_SIZE + VERSION_2_DICTIONARY_VERSION_SIZE);
+        default:
+            return NO_FLAGS;
+    }
+}
+
+// Returns if the key is found or not and reads the found value into outValue.
+/* static */ bool BinaryDictionaryHeaderReader::readHeaderValue(
+        const BinaryDictionaryInfo *const binaryDictionaryInfo,
+        const char *const key, int *outValue, const int outValueSize) {
+    if (outValueSize <= 0 || !hasHeaderAttributes(binaryDictionaryInfo->getFormat())) {
+        return false;
+    }
+    const int headerSize = getHeaderSize(binaryDictionaryInfo);
+    int pos = getHeaderOptionsPosition(binaryDictionaryInfo->getFormat());
+    while (pos < headerSize) {
+        if(ByteArrayUtils::compareStringInBufferWithCharArray(
+                binaryDictionaryInfo->getDictBuf(), key, headerSize - pos, &pos) == 0) {
+            // The key was found.
+            ByteArrayUtils::readStringAndAdvancePosition(
+                    binaryDictionaryInfo->getDictBuf(), outValueSize, outValue, &pos);
+            return true;
+        }
+        ByteArrayUtils::advancePositionToBehindString(
+                binaryDictionaryInfo->getDictBuf(), headerSize - pos, &pos);
+    }
+    // The key was not found.
+    return false;
+}
+
+/* static */ int BinaryDictionaryHeaderReader::readHeaderValueInt(
+        const BinaryDictionaryInfo *const binaryDictionaryInfo, const char *const key) {
+    const int bufferSize = LARGEST_INT_DIGIT_COUNT;
+    int intBuffer[bufferSize];
+    char charBuffer[bufferSize];
+    if (!readHeaderValue(binaryDictionaryInfo, key, intBuffer, bufferSize)) {
+        return S_INT_MIN;
+    }
+    for (int i = 0; i < bufferSize; ++i) {
+        charBuffer[i] = intBuffer[i];
+        if (charBuffer[i] == '0') {
+            break;
+        }
+        if (!isdigit(charBuffer[i])) {
+            // If not a number, return S_INT_MIN
+            return S_INT_MIN;
+        }
+    }
+    return atoi(charBuffer);
+}
+
+} // namespace latinime
diff --git a/native/jni/src/suggest/core/dictionary/binary_dictionary_header_reading_utils.h b/native/jni/src/suggest/core/dictionary/binary_dictionary_header_reading_utils.h
new file mode 100644
index 000000000..6e9dca73c
--- /dev/null
+++ b/native/jni/src/suggest/core/dictionary/binary_dictionary_header_reading_utils.h
@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) 2013, The Android Open Source Project
+ *
+ * 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.
+ */
+
+#ifndef LATINIME_DICTIONARY_HEADER_READING_UTILS_H
+#define LATINIME_DICTIONARY_HEADER_READING_UTILS_H
+
+#include <stdint.h>
+
+#include "defines.h"
+#include "suggest/core/dictionary/binary_dictionary_format_utils.h"
+
+namespace latinime {
+
+class BinaryDictionaryInfo;
+
+class BinaryDictionaryHeaderReader {
+ public:
+    typedef uint16_t DictionaryFlags;
+
+    static const int MAX_OPTION_KEY_LENGTH;
+
+    static int getHeaderSize(const BinaryDictionaryInfo *const binaryDictionaryInfo);
+
+    static DictionaryFlags getFlags(const BinaryDictionaryInfo *const binaryDictionaryInfo);
+
+    static AK_FORCE_INLINE bool supportsDynamicUpdate(const DictionaryFlags flags) {
+        return (flags & SUPPORTS_DYNAMIC_UPDATE_FLAG) != 0;
+    }
+
+    static AK_FORCE_INLINE bool requiresGermanUmlautProcessing(const DictionaryFlags flags) {
+        return (flags & GERMAN_UMLAUT_PROCESSING_FLAG) != 0;
+    }
+
+    static AK_FORCE_INLINE bool requiresFrenchLigatureProcessing(const DictionaryFlags flags) {
+        return (flags & FRENCH_LIGATURE_PROCESSING_FLAG) != 0;
+    }
+
+    static AK_FORCE_INLINE bool hasHeaderAttributes(
+            const BinaryDictionaryFormat::FORMAT_VERSION format) {
+        // Only format 2 and above have header attributes as {key,value} string pairs.
+        switch (format) {
+        case BinaryDictionaryFormat::VERSION_2:
+            return  true;
+            break;
+        default:
+            return false;
+        }
+    }
+
+    static AK_FORCE_INLINE int getHeaderOptionsPosition(
+            const BinaryDictionaryFormat::FORMAT_VERSION format) {
+        switch (format) {
+        case BinaryDictionaryFormat::VERSION_2:
+            return VERSION_2_MAGIC_NUMBER_SIZE + VERSION_2_DICTIONARY_VERSION_SIZE
+                    + VERSION_2_DICTIONARY_FLAG_SIZE + VERSION_2_DICTIONARY_HEADER_SIZE_SIZE;
+            break;
+        default:
+            return 0;
+        }
+    }
+
+    static bool readHeaderValue(
+            const BinaryDictionaryInfo *const binaryDictionaryInfo,
+            const char *const key, int *outValue, const int outValueSize);
+
+    static int readHeaderValueInt(
+            const BinaryDictionaryInfo *const binaryDictionaryInfo, const char *const key);
+
+ private:
+    DISALLOW_IMPLICIT_CONSTRUCTORS(BinaryDictionaryHeaderReader);
+
+    static const int FORMAT_VERSION_1_HEADER_SIZE;
+
+    static const int VERSION_2_MAGIC_NUMBER_SIZE;
+    static const int VERSION_2_DICTIONARY_VERSION_SIZE;
+    static const int VERSION_2_DICTIONARY_FLAG_SIZE;
+    static const int VERSION_2_DICTIONARY_HEADER_SIZE_SIZE;
+
+    static const DictionaryFlags NO_FLAGS;
+    // Flags for special processing
+    // Those *must* match the flags in makedict (FormatSpec#*_PROCESSING_FLAGS) or
+    // something very bad (like, the apocalypse) will happen. Please update both at the same time.
+    static const DictionaryFlags GERMAN_UMLAUT_PROCESSING_FLAG;
+    static const DictionaryFlags SUPPORTS_DYNAMIC_UPDATE_FLAG;
+    static const DictionaryFlags FRENCH_LIGATURE_PROCESSING_FLAG;
+    static const DictionaryFlags CONTAINS_BIGRAMS_FLAG;
+};
+}
+#endif /* LATINIME_DICTIONARY_HEADER_READING_UTILS_H */
diff --git a/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h b/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h
index 8508c6786..0b77e5ee9 100644
--- a/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h
+++ b/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h
@@ -20,16 +20,19 @@
 #include <stdint.h>
 
 #include "defines.h"
-#include "suggest/core/dictionary/binary_dictionary_format.h"
+#include "suggest/core/dictionary/binary_dictionary_format_utils.h"
+#include "suggest/core/dictionary/binary_dictionary_header.h"
 
 namespace latinime {
 
+class BinaryDictionaryHeader;
+
 class BinaryDictionaryInfo {
  public:
     BinaryDictionaryInfo(const uint8_t *const dictBuf, const int dictSize)
             : mDictBuf(dictBuf),
-              mFormat(BinaryDictionaryFormat::detectFormatVersion(mDictBuf, dictSize)),
-              mDictRoot(mDictBuf + BinaryDictionaryFormat::getHeaderSize(mDictBuf, mFormat)) {}
+              mDictionaryFormat(BinaryDictionaryFormat::detectFormatVersion(mDictBuf, dictSize)),
+              mDictionaryHeader(this), mDictRoot(mDictBuf + mDictionaryHeader.getSize()) {}
 
     AK_FORCE_INLINE const uint8_t *getDictBuf() const {
         return mDictBuf;
@@ -40,18 +43,23 @@ class BinaryDictionaryInfo {
     }
 
     AK_FORCE_INLINE BinaryDictionaryFormat::FORMAT_VERSION getFormat() const {
-        return mFormat;
+        return mDictionaryFormat;
     }
 
     AK_FORCE_INLINE int getRootPosition() const {
         return 0;
     }
 
+    AK_FORCE_INLINE const BinaryDictionaryHeader *getHeader() const {
+        return &mDictionaryHeader;
+    }
+
  private:
     DISALLOW_COPY_AND_ASSIGN(BinaryDictionaryInfo);
 
     const uint8_t *const mDictBuf;
-    const BinaryDictionaryFormat::FORMAT_VERSION mFormat;
+    const BinaryDictionaryFormat::FORMAT_VERSION mDictionaryFormat;
+    const BinaryDictionaryHeader mDictionaryHeader;
     const uint8_t *const mDictRoot;
 };
 }
diff --git a/native/jni/src/suggest/core/dictionary/binary_format.h b/native/jni/src/suggest/core/dictionary/binary_format.h
index c82065f97..f580bdad5 100644
--- a/native/jni/src/suggest/core/dictionary/binary_format.h
+++ b/native/jni/src/suggest/core/dictionary/binary_format.h
@@ -17,7 +17,6 @@
 #ifndef LATINIME_BINARY_FORMAT_H
 #define LATINIME_BINARY_FORMAT_H
 
-#include <cstdlib>
 #include <stdint.h>
 
 #include "suggest/core/dictionary/bloom_filter.h"
@@ -61,17 +60,9 @@ class BinaryFormat {
     // Mask and flags for attribute address type selection.
     static const int MASK_ATTRIBUTE_ADDRESS_TYPE = 0x30;
 
-    static const int UNKNOWN_FORMAT = -1;
     static const int SHORTCUT_LIST_SIZE_SIZE = 2;
 
-    static int detectFormat(const uint8_t *const dict, const int dictSize);
-    static int getHeaderSize(const uint8_t *const dict, const int dictSize);
-    static int getFlags(const uint8_t *const dict, const int dictSize);
     static bool hasBlacklistedOrNotAWordFlag(const int flags);
-    static void readHeaderValue(const uint8_t *const dict, const int dictSize,
-            const char *const key, int *outValue, const int outValueSize);
-    static int readHeaderValueInt(const uint8_t *const dict, const int dictSize,
-            const char *const key);
     static int getGroupCountAndForwardPointer(const uint8_t *const dict, int *pos);
     static uint8_t getFlagsAndForwardPointer(const uint8_t *const dict, int *pos);
     static int getCodePointAndForwardPointer(const uint8_t *const dict, int *pos);
@@ -93,20 +84,11 @@ class BinaryFormat {
             int *outWord, int *outUnigramProbability);
     static int getBigramProbabilityFromHashMap(const int position,
             const hash_map_compat<int, int> *bigramMap, const int unigramProbability);
-    static float getMultiWordCostMultiplier(const uint8_t *const dict, const int dictSize);
     static void fillBigramProbabilityToHashMap(const uint8_t *const root, int position,
             hash_map_compat<int, int> *bigramMap);
     static int getBigramProbability(const uint8_t *const root, int position,
             const int nextPosition, const int unigramProbability);
 
-    // Flags for special processing
-    // Those *must* match the flags in makedict (BinaryDictInputOutput#*_PROCESSING_FLAG) or
-    // something very bad (like, the apocalypse) will happen. Please update both at the same time.
-    enum {
-        REQUIRES_GERMAN_UMLAUT_PROCESSING = 0x1,
-        REQUIRES_FRENCH_LIGATURES_PROCESSING = 0x4
-    };
-
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(BinaryFormat);
     static int getBigramListPositionForWordPosition(const uint8_t *const root, int position);
@@ -119,20 +101,6 @@ class BinaryFormat {
     static const int FLAG_ATTRIBUTE_ADDRESS_TYPE_TWOBYTES = 0x20;
     static const int FLAG_ATTRIBUTE_ADDRESS_TYPE_THREEBYTES = 0x30;
 
-    // Any file smaller than this is not a dictionary.
-    static const int DICTIONARY_MINIMUM_SIZE = 4;
-    // Originally, format version 1 had a 16-bit magic number, then the version number `01'
-    // then options that must be 0. Hence the first 32-bits of the format are always as follow
-    // and it's okay to consider them a magic number as a whole.
-    static const int FORMAT_VERSION_1_MAGIC_NUMBER = 0x78B10100;
-    static const int FORMAT_VERSION_1_HEADER_SIZE = 5;
-    // The versions of Latin IME that only handle format version 1 only test for the magic
-    // number, so we had to change it so that version 2 files would be rejected by older
-    // implementations. On this occasion, we made the magic number 32 bits long.
-    static const int FORMAT_VERSION_2_MAGIC_NUMBER = -1681835266; // 0x9BC13AFE
-    // Magic number (4 bytes), version (2 bytes), options (2 bytes), header size (4 bytes) = 12
-    static const int FORMAT_VERSION_2_MINIMUM_SIZE = 12;
-
     static const int CHARACTER_ARRAY_TERMINATOR_SIZE = 1;
     static const int MINIMAL_ONE_BYTE_CHARACTER_VALUE = 0x20;
     static const int CHARACTER_ARRAY_TERMINATOR = 0x1F;
@@ -142,122 +110,10 @@ class BinaryFormat {
     static int skipBigrams(const uint8_t *const dict, const uint8_t flags, const int pos);
 };
 
-AK_FORCE_INLINE int BinaryFormat::detectFormat(const uint8_t *const dict, const int dictSize) {
-    // The magic number is stored big-endian.
-    // If the dictionary is less than 4 bytes, we can't even read the magic number, so we don't
-    // understand this format.
-    if (dictSize < DICTIONARY_MINIMUM_SIZE) return UNKNOWN_FORMAT;
-    const int magicNumber = (dict[0] << 24) + (dict[1] << 16) + (dict[2] << 8) + dict[3];
-    switch (magicNumber) {
-    case FORMAT_VERSION_1_MAGIC_NUMBER:
-        // Format 1 header is exactly 5 bytes long and looks like:
-        // Magic number (2 bytes) 0x78 0xB1
-        // Version number (1 byte) 0x01
-        // Options (2 bytes) must be 0x00 0x00
-        return 1;
-    case FORMAT_VERSION_2_MAGIC_NUMBER:
-        // Version 2 dictionaries are at least 12 bytes long (see below details for the header).
-        // If this dictionary has the version 2 magic number but is less than 12 bytes long, then
-        // it's an unknown format and we need to avoid confidently reading the next bytes.
-        if (dictSize < FORMAT_VERSION_2_MINIMUM_SIZE) return UNKNOWN_FORMAT;
-        // Format 2 header is as follows:
-        // Magic number (4 bytes) 0x9B 0xC1 0x3A 0xFE
-        // Version number (2 bytes) 0x00 0x02
-        // Options (2 bytes)
-        // Header size (4 bytes) : integer, big endian
-        return (dict[4] << 8) + dict[5];
-    default:
-        return UNKNOWN_FORMAT;
-    }
-}
-
-inline int BinaryFormat::getFlags(const uint8_t *const dict, const int dictSize) {
-    switch (detectFormat(dict, dictSize)) {
-    case 1:
-        return NO_FLAGS; // TODO: NO_FLAGS is unused anywhere else?
-    default:
-        return (dict[6] << 8) + dict[7];
-    }
-}
-
 inline bool BinaryFormat::hasBlacklistedOrNotAWordFlag(const int flags) {
     return (flags & (FLAG_IS_BLACKLISTED | FLAG_IS_NOT_A_WORD)) != 0;
 }
 
-inline int BinaryFormat::getHeaderSize(const uint8_t *const dict, const int dictSize) {
-    switch (detectFormat(dict, dictSize)) {
-    case 1:
-        return FORMAT_VERSION_1_HEADER_SIZE;
-    case 2:
-        // See the format of the header in the comment in detectFormat() above
-        return (dict[8] << 24) + (dict[9] << 16) + (dict[10] << 8) + dict[11];
-    default:
-        return S_INT_MAX;
-    }
-}
-
-inline void BinaryFormat::readHeaderValue(const uint8_t *const dict, const int dictSize,
-        const char *const key, int *outValue, const int outValueSize) {
-    int outValueIndex = 0;
-    // Only format 2 and above have header attributes as {key,value} string pairs. For prior
-    // formats, we just return an empty string, as if the key wasn't found.
-    if (2 <= detectFormat(dict, dictSize)) {
-        const int headerOptionsOffset = 4 /* magic number */
-                + 2 /* dictionary version */ + 2 /* flags */;
-        const int headerSize =
-                (dict[headerOptionsOffset] << 24) + (dict[headerOptionsOffset + 1] << 16)
-                + (dict[headerOptionsOffset + 2] << 8) + dict[headerOptionsOffset + 3];
-        const int headerEnd = headerOptionsOffset + 4 + headerSize;
-        int index = headerOptionsOffset + 4;
-        while (index < headerEnd) {
-            int keyIndex = 0;
-            int codePoint = getCodePointAndForwardPointer(dict, &index);
-            while (codePoint != NOT_A_CODE_POINT) {
-                if (codePoint != key[keyIndex++]) {
-                    break;
-                }
-                codePoint = getCodePointAndForwardPointer(dict, &index);
-            }
-            if (codePoint == NOT_A_CODE_POINT && key[keyIndex] == 0) {
-                // We found the key! Copy and return the value.
-                codePoint = getCodePointAndForwardPointer(dict, &index);
-                while (codePoint != NOT_A_CODE_POINT && outValueIndex < outValueSize) {
-                    outValue[outValueIndex++] = codePoint;
-                    codePoint = getCodePointAndForwardPointer(dict, &index);
-                }
-                // Finished copying. Break to go to the termination code.
-                break;
-            }
-            // We didn't find the key, skip the remainder of it and its value
-            while (codePoint != NOT_A_CODE_POINT) {
-                codePoint = getCodePointAndForwardPointer(dict, &index);
-            }
-            codePoint = getCodePointAndForwardPointer(dict, &index);
-            while (codePoint != NOT_A_CODE_POINT) {
-                codePoint = getCodePointAndForwardPointer(dict, &index);
-            }
-        }
-        // We couldn't find it - fall through and return an empty value.
-    }
-    // Put a terminator 0 if possible at all (always unless outValueSize is <= 0)
-    if (outValueIndex >= outValueSize) outValueIndex = outValueSize - 1;
-    if (outValueIndex >= 0) outValue[outValueIndex] = 0;
-}
-
-inline int BinaryFormat::readHeaderValueInt(const uint8_t *const dict, const int dictSize,
-        const char *const key) {
-    const int bufferSize = LARGEST_INT_DIGIT_COUNT;
-    int intBuffer[bufferSize];
-    char charBuffer[bufferSize];
-    BinaryFormat::readHeaderValue(dict, dictSize, key, intBuffer, bufferSize);
-    for (int i = 0; i < bufferSize; ++i) {
-        charBuffer[i] = intBuffer[i];
-    }
-    // If not a number, return S_INT_MIN
-    if (!isdigit(charBuffer[0])) return S_INT_MIN;
-    return atoi(charBuffer);
-}
-
 AK_FORCE_INLINE int BinaryFormat::getGroupCountAndForwardPointer(const uint8_t *const dict,
         int *pos) {
     const int msb = dict[(*pos)++];
@@ -265,18 +121,6 @@ AK_FORCE_INLINE int BinaryFormat::getGroupCountAndForwardPointer(const uint8_t *
     return ((msb & 0x7F) << 8) | dict[(*pos)++];
 }
 
-inline float BinaryFormat::getMultiWordCostMultiplier(const uint8_t *const dict,
-        const int dictSize) {
-    const int headerValue = readHeaderValueInt(dict, dictSize, "MULTIPLE_WORDS_DEMOTION_RATE");
-    if (headerValue == S_INT_MIN) {
-        return 1.0f;
-    }
-    if (headerValue <= 0) {
-        return static_cast<float>(MAX_VALUE_FOR_WEIGHTING);
-    }
-    return 100.0f / static_cast<float>(headerValue);
-}
-
 inline uint8_t BinaryFormat::getFlagsAndForwardPointer(const uint8_t *const dict, int *pos) {
     return dict[(*pos)++];
 }
diff --git a/native/jni/src/suggest/core/dictionary/byte_array_utils.h b/native/jni/src/suggest/core/dictionary/byte_array_utils.h
index 832b74725..d3321f624 100644
--- a/native/jni/src/suggest/core/dictionary/byte_array_utils.h
+++ b/native/jni/src/suggest/core/dictionary/byte_array_utils.h
@@ -116,8 +116,8 @@ class ByteArrayUtils {
      * Reads code points until the terminator is found.
      */
     // Returns the length of the string.
-    static int readStringAndAdvancePosition(const uint8_t *const buffer, int *const pos,
-            int *const outBuffer, const int maxLength) {
+    static int readStringAndAdvancePosition(const uint8_t *const buffer,
+            const int maxLength, int *const outBuffer, int *const pos) {
         int length = 0;
         int codePoint = readCodePointAndAdvancePosition(buffer, pos);
         while (NOT_A_CODE_POINT != codePoint && length < maxLength) {
@@ -129,7 +129,7 @@ class ByteArrayUtils {
 
     // Advances the position and returns the length of the string.
     static int advancePositionToBehindString(
-            const uint8_t *const buffer, int *const pos, const int maxLength) {
+            const uint8_t *const buffer, const int maxLength, int *const pos) {
         int length = 0;
         int codePoint = readCodePointAndAdvancePosition(buffer, pos);
         while (NOT_A_CODE_POINT != codePoint && length < maxLength) {
@@ -138,6 +138,39 @@ class ByteArrayUtils {
         return length;
     }
 
+    // Returns an integer less than, equal to, or greater than zero when string starting from pos
+    // in buffer is less than, match, or is greater than charArray.
+    static AK_FORCE_INLINE int compareStringInBufferWithCharArray(const uint8_t *const buffer,
+            const char *const charArray, const int maxLength, int *const pos) {
+        int index = 0;
+        int codePoint = readCodePointAndAdvancePosition(buffer, pos);
+        const uint8_t *const uint8CharArrayForComparison =
+                reinterpret_cast<const uint8_t *>(charArray);
+        while (NOT_A_CODE_POINT != codePoint
+                && '\0' != uint8CharArrayForComparison[index] && index < maxLength) {
+            if (codePoint != uint8CharArrayForComparison[index]) {
+                // Different character is found.
+                // Skip the rest of the string in the buffer.
+                advancePositionToBehindString(buffer, maxLength - index, pos);
+                return codePoint - uint8CharArrayForComparison[index];
+            }
+            // Advance
+            codePoint = readCodePointAndAdvancePosition(buffer, pos);
+            ++index;
+        }
+        if (NOT_A_CODE_POINT != codePoint && index < maxLength) {
+            // Skip the rest of the string in the buffer.
+            advancePositionToBehindString(buffer, maxLength - index, pos);
+        }
+        if (NOT_A_CODE_POINT == codePoint && '\0' == uint8CharArrayForComparison[index]) {
+            // When both of the last characters are terminals, we consider the string in the buffer
+            // matches the given char array
+            return 0;
+        } else {
+            return codePoint - uint8CharArrayForComparison[index];
+        }
+    }
+
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(ByteArrayUtils);
 
diff --git a/native/jni/src/suggest/core/dictionary/dictionary.cpp b/native/jni/src/suggest/core/dictionary/dictionary.cpp
index 2d4ad5df5..561e22d2d 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary.cpp
+++ b/native/jni/src/suggest/core/dictionary/dictionary.cpp
@@ -33,11 +33,10 @@
 namespace latinime {
 
 Dictionary::Dictionary(void *dict, int dictSize, int mmapFd, int dictBufAdjust)
-        : mBinaryDicitonaryInfo(static_cast<const uint8_t *>(dict), dictSize),
+        : mBinaryDictionaryInfo(static_cast<const uint8_t *>(dict), dictSize),
           mDictSize(dictSize),
-          mDictFlags(BinaryFormat::getFlags(mBinaryDicitonaryInfo.getDictBuf(), dictSize)),
           mMmapFd(mmapFd), mDictBufAdjust(dictBufAdjust),
-          mBigramDictionary(new BigramDictionary(&mBinaryDicitonaryInfo)),
+          mBigramDictionary(new BigramDictionary(&mBinaryDictionaryInfo)),
           mGestureSuggest(new Suggest(GestureSuggestPolicyFactory::getGestureSuggestPolicy())),
           mTypingSuggest(new Suggest(TypingSuggestPolicyFactory::getTypingSuggestPolicy())) {
 }
@@ -85,7 +84,7 @@ int Dictionary::getBigrams(const int *word, int length, int *inputCodePoints, in
 }
 
 int Dictionary::getProbability(const int *word, int length) const {
-    const uint8_t *const root = mBinaryDicitonaryInfo.getDictRoot();
+    const uint8_t *const root = mBinaryDictionaryInfo.getDictRoot();
     int pos = BinaryFormat::getTerminalPosition(root, word, length,
             false /* forceLowerCaseSearch */);
     if (NOT_VALID_WORD == pos) {
@@ -112,8 +111,4 @@ bool Dictionary::isValidBigram(const int *word1, int length1, const int *word2,
     return mBigramDictionary->isValidBigram(word1, length1, word2, length2);
 }
 
-int Dictionary::getDictFlags() const {
-    return mDictFlags;
-}
-
 } // namespace latinime
diff --git a/native/jni/src/suggest/core/dictionary/dictionary.h b/native/jni/src/suggest/core/dictionary/dictionary.h
index 1f25080b1..151f26183 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary.h
+++ b/native/jni/src/suggest/core/dictionary/dictionary.h
@@ -66,22 +66,20 @@ class Dictionary {
     int getProbability(const int *word, int length) const;
     bool isValidBigram(const int *word1, int length1, const int *word2, int length2) const;
     const BinaryDictionaryInfo *getBinaryDictionaryInfo() const {
-        return &mBinaryDicitonaryInfo;
+        return &mBinaryDictionaryInfo;
     }
     int getDictSize() const { return mDictSize; }
     int getMmapFd() const { return mMmapFd; }
     int getDictBufAdjust() const { return mDictBufAdjust; }
-    int getDictFlags() const;
     virtual ~Dictionary();
 
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(Dictionary);
 
-    const BinaryDictionaryInfo mBinaryDicitonaryInfo;
+    const BinaryDictionaryInfo mBinaryDictionaryInfo;
     // Used only for the mmap version of dictionary loading, but we use these as dummy variables
     // also for the malloc version.
     const int mDictSize;
-    const int mDictFlags;
     const int mMmapFd;
     const int mDictBufAdjust;
 
diff --git a/native/jni/src/suggest/core/dictionary/digraph_utils.cpp b/native/jni/src/suggest/core/dictionary/digraph_utils.cpp
index f53e56ef1..af378b1b7 100644
--- a/native/jni/src/suggest/core/dictionary/digraph_utils.cpp
+++ b/native/jni/src/suggest/core/dictionary/digraph_utils.cpp
@@ -16,8 +16,10 @@
 
 #include "suggest/core/dictionary/digraph_utils.h"
 
+#include <cstdlib>
+
 #include "defines.h"
-#include "suggest/core/dictionary/binary_format.h"
+#include "suggest/core/dictionary/binary_dictionary_header.h"
 #include "utils/char_utils.h"
 
 namespace latinime {
@@ -33,8 +35,8 @@ const DigraphUtils::DigraphType DigraphUtils::USED_DIGRAPH_TYPES[] =
         { DIGRAPH_TYPE_GERMAN_UMLAUT, DIGRAPH_TYPE_FRENCH_LIGATURES };
 
 /* static */ bool DigraphUtils::hasDigraphForCodePoint(
-        const int dictFlags, const int compositeGlyphCodePoint) {
-    const DigraphUtils::DigraphType digraphType = getDigraphTypeForDictionary(dictFlags);
+        const BinaryDictionaryHeader *const header, const int compositeGlyphCodePoint) {
+    const DigraphUtils::DigraphType digraphType = getDigraphTypeForDictionary(header);
     if (DigraphUtils::getDigraphForDigraphTypeAndCodePoint(digraphType, compositeGlyphCodePoint)) {
         return true;
     }
@@ -43,24 +45,16 @@ const DigraphUtils::DigraphType DigraphUtils::USED_DIGRAPH_TYPES[] =
 
 // Returns the digraph type associated with the given dictionary.
 /* static */ DigraphUtils::DigraphType DigraphUtils::getDigraphTypeForDictionary(
-        const int dictFlags) {
-    if (BinaryFormat::REQUIRES_GERMAN_UMLAUT_PROCESSING & dictFlags) {
+        const BinaryDictionaryHeader *const header) {
+    if (header->requiresGermanUmlautProcessing()) {
         return DIGRAPH_TYPE_GERMAN_UMLAUT;
     }
-    if (BinaryFormat::REQUIRES_FRENCH_LIGATURES_PROCESSING & dictFlags) {
+    if (header->requiresFrenchLigatureProcessing()) {
         return DIGRAPH_TYPE_FRENCH_LIGATURES;
     }
     return DIGRAPH_TYPE_NONE;
 }
 
-// Retrieves the set of all digraphs associated with the given dictionary flags.
-// Returns the size of the digraph array, or 0 if none exist.
-/* static */ int DigraphUtils::getAllDigraphsForDictionaryAndReturnSize(
-        const int dictFlags, const DigraphUtils::digraph_t **const digraphs) {
-    const DigraphUtils::DigraphType digraphType = getDigraphTypeForDictionary(dictFlags);
-    return getAllDigraphsForDigraphTypeAndReturnSize(digraphType, digraphs);
-}
-
 // Returns the digraph codepoint for the given composite glyph codepoint and digraph codepoint index
 // (which specifies the first or second codepoint in the digraph).
 /* static */ int DigraphUtils::getDigraphCodePointForIndex(const int compositeGlyphCodePoint,
@@ -124,7 +118,7 @@ const DigraphUtils::DigraphType DigraphUtils::USED_DIGRAPH_TYPES[] =
     const DigraphUtils::digraph_t *digraphs = 0;
     const int compositeGlyphLowerCodePoint = CharUtils::toLowerCase(compositeGlyphCodePoint);
     const int digraphsSize =
-            DigraphUtils::getAllDigraphsForDictionaryAndReturnSize(digraphType, &digraphs);
+            DigraphUtils::getAllDigraphsForDigraphTypeAndReturnSize(digraphType, &digraphs);
     for (int i = 0; i < digraphsSize; i++) {
         if (digraphs[i].compositeGlyph == compositeGlyphLowerCodePoint) {
             return &digraphs[i];
diff --git a/native/jni/src/suggest/core/dictionary/digraph_utils.h b/native/jni/src/suggest/core/dictionary/digraph_utils.h
index c1205940c..9d74fe3a6 100644
--- a/native/jni/src/suggest/core/dictionary/digraph_utils.h
+++ b/native/jni/src/suggest/core/dictionary/digraph_utils.h
@@ -21,6 +21,8 @@
 
 namespace latinime {
 
+class BinaryDictionaryHeader;
+
 class DigraphUtils {
  public:
     typedef enum {
@@ -37,17 +39,14 @@ class DigraphUtils {
 
     typedef struct { int first; int second; int compositeGlyph; } digraph_t;
 
-    static bool hasDigraphForCodePoint(const int dictFlags, const int compositeGlyphCodePoint);
-    static int getAllDigraphsForDictionaryAndReturnSize(
-            const int dictFlags, const digraph_t **const digraphs);
-    static int getDigraphCodePointForIndex(const int dictFlags, const int compositeGlyphCodePoint,
-            const DigraphCodePointIndex digraphCodePointIndex);
+    static bool hasDigraphForCodePoint(
+            const BinaryDictionaryHeader *const header, const int compositeGlyphCodePoint);
     static int getDigraphCodePointForIndex(const int compositeGlyphCodePoint,
             const DigraphCodePointIndex digraphCodePointIndex);
 
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(DigraphUtils);
-    static DigraphType getDigraphTypeForDictionary(const int dictFlags);
+    static DigraphType getDigraphTypeForDictionary(const BinaryDictionaryHeader *const header);
     static int getAllDigraphsForDigraphTypeAndReturnSize(
             const DigraphType digraphType, const digraph_t **const digraphs);
     static const digraph_t *getDigraphForCodePoint(const int compositeGlyphCodePoint);
diff --git a/native/jni/src/suggest/core/session/dic_traverse_session.cpp b/native/jni/src/suggest/core/session/dic_traverse_session.cpp
index c398caefa..774d6074e 100644
--- a/native/jni/src/suggest/core/session/dic_traverse_session.cpp
+++ b/native/jni/src/suggest/core/session/dic_traverse_session.cpp
@@ -19,6 +19,7 @@
 #include "defines.h"
 #include "jni.h"
 #include "suggest/core/dicnode/dic_node_utils.h"
+#include "suggest/core/dictionary/binary_dictionary_header.h"
 #include "suggest/core/dictionary/binary_dictionary_info.h"
 #include "suggest/core/dictionary/binary_format.h"
 #include "suggest/core/dictionary/dictionary.h"
@@ -28,9 +29,8 @@ namespace latinime {
 void DicTraverseSession::init(const Dictionary *const dictionary, const int *prevWord,
         int prevWordLength, const SuggestOptions *const suggestOptions) {
     mDictionary = dictionary;
-    mMultiWordCostMultiplier = BinaryFormat::getMultiWordCostMultiplier(
-            mDictionary->getBinaryDictionaryInfo()->getDictBuf(),
-            mDictionary->getDictSize());
+    mMultiWordCostMultiplier = mDictionary->getBinaryDictionaryInfo()
+            ->getHeader()->getMultiWordCostMultiplier();
     mSuggestOptions = suggestOptions;
     if (!prevWord) {
         mPrevWordPos = NOT_VALID_WORD;
@@ -63,10 +63,6 @@ const BinaryDictionaryInfo *DicTraverseSession::getBinaryDictionaryInfo() const
     return mDictionary->getBinaryDictionaryInfo();
 }
 
-int DicTraverseSession::getDictFlags() const {
-    return mDictionary->getDictFlags();
-}
-
 void DicTraverseSession::resetCache(const int nextActiveCacheSize, const int maxWords) {
     mDicNodesCache.reset(nextActiveCacheSize, maxWords);
     mMultiBigramMap.clear();
diff --git a/native/jni/src/suggest/core/session/dic_traverse_session.h b/native/jni/src/suggest/core/session/dic_traverse_session.h
index 630b3b59b..f95a0b23d 100644
--- a/native/jni/src/suggest/core/session/dic_traverse_session.h
+++ b/native/jni/src/suggest/core/session/dic_traverse_session.h
@@ -77,7 +77,6 @@ class DicTraverseSession {
 
     // TODO: Remove
     const BinaryDictionaryInfo *getBinaryDictionaryInfo() const;
-    int getDictFlags() const;
 
     //--------------------
     // getters and setters
diff --git a/native/jni/src/suggest/core/suggest.cpp b/native/jni/src/suggest/core/suggest.cpp
index 1f108e400..6c4a6c166 100644
--- a/native/jni/src/suggest/core/suggest.cpp
+++ b/native/jni/src/suggest/core/suggest.cpp
@@ -19,6 +19,7 @@
 #include "suggest/core/dicnode/dic_node.h"
 #include "suggest/core/dicnode/dic_node_priority_queue.h"
 #include "suggest/core/dicnode/dic_node_vector.h"
+#include "suggest/core/dictionary/binary_dictionary_info.h"
 #include "suggest/core/dictionary/dictionary.h"
 #include "suggest/core/dictionary/digraph_utils.h"
 #include "suggest/core/dictionary/shortcut_utils.h"
@@ -294,7 +295,8 @@ void Suggest::expandCurrentDicNodes(DicTraverseSession *traverseSession) const {
                     processDicNodeAsMatch(traverseSession, childDicNode);
                     continue;
                 }
-                if (DigraphUtils::hasDigraphForCodePoint(traverseSession->getDictFlags(),
+                if (DigraphUtils::hasDigraphForCodePoint(
+                        traverseSession->getBinaryDictionaryInfo()->getHeader(),
                         childDicNode->getNodeCodePoint())) {
                     correctionDicNode.initByCopy(childDicNode);
                     correctionDicNode.advanceDigraphIndex();