Add spellcheck and word suggestion to the prediction service

third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_writing_utils.cpp

Index: third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_writing_utils.cpp
diff --git a/third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_writing_utils.cpp b/third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_writing_utils.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..195bf2ac1550556fb09186ebaafccf310ebf0ad6
--- /dev/null
+++ b/third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_writing_utils.cpp
@@ -0,0 +1,132 @@
+/*
+ * 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 "third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_writing_utils.h"
+
+#include <cstddef>
+#include <cstdint>
+#include <cstdlib>
+
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/utils/buffer_with_extendable_buffer.h"
+
+namespace latinime {
+
+const size_t DynamicPtWritingUtils::MAX_PTNODE_ARRAY_SIZE_TO_USE_SMALL_SIZE_FIELD = 0x7F;
+const size_t DynamicPtWritingUtils::MAX_PTNODE_ARRAY_SIZE = 0x7FFF;
+const int DynamicPtWritingUtils::SMALL_PTNODE_ARRAY_SIZE_FIELD_SIZE = 1;
+const int DynamicPtWritingUtils::LARGE_PTNODE_ARRAY_SIZE_FIELD_SIZE = 2;
+const int DynamicPtWritingUtils::LARGE_PTNODE_ARRAY_SIZE_FIELD_SIZE_FLAG = 0x8000;
+const int DynamicPtWritingUtils::DICT_OFFSET_FIELD_SIZE = 3;
+const int DynamicPtWritingUtils::MAX_DICT_OFFSET_VALUE = 0x7FFFFF;
+const int DynamicPtWritingUtils::MIN_DICT_OFFSET_VALUE = -0x7FFFFF;
+const int DynamicPtWritingUtils::DICT_OFFSET_NEGATIVE_FLAG = 0x800000;
+const int DynamicPtWritingUtils::NODE_FLAG_FIELD_SIZE = 1;
+
+/* static */ bool DynamicPtWritingUtils::writeEmptyDictionary(
+        BufferWithExtendableBuffer *const buffer, const int rootPos) {
+    int writingPos = rootPos;
+    if (!writePtNodeArraySizeAndAdvancePosition(buffer, 0 /* arraySize */, &writingPos)) {
+        return false;
+    }
+    return writeForwardLinkPositionAndAdvancePosition(buffer, NOT_A_DICT_POS /* forwardLinkPos */,
+            &writingPos);
+}
+
+/* static */ bool DynamicPtWritingUtils::writeForwardLinkPositionAndAdvancePosition(
+        BufferWithExtendableBuffer *const buffer, const int forwardLinkPos,
+        int *const forwardLinkFieldPos) {
+    return writeDictOffset(buffer, forwardLinkPos, (*forwardLinkFieldPos), forwardLinkFieldPos);
+}
+
+/* static */ bool DynamicPtWritingUtils::writePtNodeArraySizeAndAdvancePosition(
+        BufferWithExtendableBuffer *const buffer, const size_t arraySize,
+        int *const arraySizeFieldPos) {
+    // Currently, all array size field to be created has LARGE_PTNODE_ARRAY_SIZE_FIELD_SIZE to
+    // simplify updating process.
+    // TODO: Use SMALL_PTNODE_ARRAY_SIZE_FIELD_SIZE for small arrays.
+    /*if (arraySize <= MAX_PTNODE_ARRAY_SIZE_TO_USE_SMALL_SIZE_FIELD) {
+        return buffer->writeUintAndAdvancePosition(arraySize, SMALL_PTNODE_ARRAY_SIZE_FIELD_SIZE,
+                arraySizeFieldPos);
+    } else */
+    if (arraySize <= MAX_PTNODE_ARRAY_SIZE) {
+        uint32_t data = arraySize | LARGE_PTNODE_ARRAY_SIZE_FIELD_SIZE_FLAG;
+        return buffer->writeUintAndAdvancePosition(data, LARGE_PTNODE_ARRAY_SIZE_FIELD_SIZE,
+                arraySizeFieldPos);
+    } else {
+        AKLOGI("PtNode array size cannot be written because arraySize is too large: %zd",
+                arraySize);
+        ASSERT(false);
+        return false;
+    }
+}
+
+/* static */ bool DynamicPtWritingUtils::writeFlagsAndAdvancePosition(
+        BufferWithExtendableBuffer *const buffer,
+        const DynamicPtReadingUtils::NodeFlags nodeFlags, int *const nodeFlagsFieldPos) {
+    return buffer->writeUintAndAdvancePosition(nodeFlags, NODE_FLAG_FIELD_SIZE, nodeFlagsFieldPos);
+}
+
+// Note that parentOffset is offset from node's head position.
+/* static */ bool DynamicPtWritingUtils::writeParentPosOffsetAndAdvancePosition(
+        BufferWithExtendableBuffer *const buffer, const int parentPos, const int basePos,
+        int *const parentPosFieldPos) {
+    return writeDictOffset(buffer, parentPos, basePos, parentPosFieldPos);
+}
+
+/* static */ bool DynamicPtWritingUtils::writeCodePointsAndAdvancePosition(
+        BufferWithExtendableBuffer *const buffer, const int *const codePoints,
+        const int codePointCount, int *const codePointFieldPos) {
+    if (codePointCount <= 0) {
+        AKLOGI("code points cannot be written because codePointCount is invalid: %d",
+                codePointCount);
+        ASSERT(false);
+        return false;
+    }
+    const bool hasMultipleCodePoints = codePointCount > 1;
+    return buffer->writeCodePointsAndAdvancePosition(codePoints, codePointCount,
+            hasMultipleCodePoints, codePointFieldPos);
+}
+
+/* static */ bool DynamicPtWritingUtils::writeChildrenPositionAndAdvancePosition(
+        BufferWithExtendableBuffer *const buffer, const int childrenPosition,
+        int *const childrenPositionFieldPos) {
+    return writeDictOffset(buffer, childrenPosition, (*childrenPositionFieldPos),
+            childrenPositionFieldPos);
+}
+
+/* static */ bool DynamicPtWritingUtils::writeDictOffset(BufferWithExtendableBuffer *const buffer,
+        const int targetPos, const int basePos, int *const offsetFieldPos) {
+    int offset = targetPos - basePos;
+    if (targetPos == NOT_A_DICT_POS) {
+        offset = DynamicPtReadingUtils::DICT_OFFSET_INVALID;
+    } else if (offset == 0) {
+        offset = DynamicPtReadingUtils::DICT_OFFSET_ZERO_OFFSET;
+    }
+    if (offset > MAX_DICT_OFFSET_VALUE || offset < MIN_DICT_OFFSET_VALUE) {
+        AKLOGI("offset cannot be written because the offset is too large or too small: %d",
+                offset);
+        ASSERT(false);
+        return false;
+    }
+    uint32_t data = 0;
+    if (offset >= 0) {
+        data = offset;
+    } else {
+        data = abs(offset) | DICT_OFFSET_NEGATIVE_FLAG;
+    }
+    return buffer->writeUintAndAdvancePosition(data, DICT_OFFSET_FIELD_SIZE, offsetFieldPos);
+}
+}