Add spellcheck and word suggestion to the prediction service

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

Index: third_party/prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_writing_utils.cpp
diff --git a/third_party/prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_writing_utils.cpp b/third_party/prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_writing_utils.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..b6f5e300f9795c2e1b7f67d13450ae7ab72c5472
--- /dev/null
+++ b/third_party/prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_writing_utils.cpp
@@ -0,0 +1,159 @@
+/*
+ * 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/prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_writing_utils.h"
+
+#include <cstddef>
+#include <cstdint>
+#include <cstdlib>
+
+#include "third_party/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);
+}
+}