Implement additional proximity characters in the native code
Bug: 4343280

Change-Id: I9bbc5cab2fef1ee80c1fe32017df811ef8af10bc
diff --git a/native/src/additional_proximity_chars.h b/native/src/additional_proximity_chars.h
new file mode 100644
index 0000000..b76726c
--- /dev/null
+++ b/native/src/additional_proximity_chars.h
@@ -0,0 +1,92 @@
+/*
+ * Copyright (C) 2012 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_ADDITIONAL_PROXIMITY_CHARS_H
+#define LATINIME_ADDITIONAL_PROXIMITY_CHARS_H
+
+#include <stdint.h>
+#include <string>
+
+namespace latinime {
+
+class AdditionalProximityChars {
+ private:
+    static const std::string LOCALE_EN_US;
+    static const int EN_US_ADDITIONAL_A_SIZE = 4;
+    static const uint16_t EN_US_ADDITIONAL_A[];
+    static const int EN_US_ADDITIONAL_E_SIZE = 4;
+    static const uint16_t EN_US_ADDITIONAL_E[];
+    static const int EN_US_ADDITIONAL_I_SIZE = 4;
+    static const uint16_t EN_US_ADDITIONAL_I[];
+    static const int EN_US_ADDITIONAL_O_SIZE = 4;
+    static const uint16_t EN_US_ADDITIONAL_O[];
+    static const int EN_US_ADDITIONAL_U_SIZE = 4;
+    static const uint16_t EN_US_ADDITIONAL_U[];
+
+    static bool isEnLocale(std::string* locale_str) {
+        return locale_str && locale_str->size() >= LOCALE_EN_US.size()
+                && locale_str->compare(0, LOCALE_EN_US.size(), LOCALE_EN_US);
+    }
+
+ public:
+    static int getAdditionalCharsSize(std::string* locale_str, uint16_t c) {
+        if (!isEnLocale(locale_str)) {
+            return 0;
+        }
+        switch(c) {
+        case 'a':
+            return EN_US_ADDITIONAL_A_SIZE;
+        case 'e':
+            return EN_US_ADDITIONAL_E_SIZE;
+        case 'i':
+            return EN_US_ADDITIONAL_I_SIZE;
+        case 'o':
+            return EN_US_ADDITIONAL_O_SIZE;
+        case 'u':
+            return EN_US_ADDITIONAL_U_SIZE;
+        default:
+            return 0;
+        }
+    }
+
+    static const uint16_t* getAdditionalChars(std::string* locale_str, uint16_t c) {
+        if (!isEnLocale(locale_str)) {
+            return 0;
+        }
+        switch(c) {
+        case 'a':
+            return EN_US_ADDITIONAL_A;
+        case 'e':
+            return EN_US_ADDITIONAL_E;
+        case 'i':
+            return EN_US_ADDITIONAL_I;
+        case 'o':
+            return EN_US_ADDITIONAL_O;
+        case 'u':
+            return EN_US_ADDITIONAL_U;
+        default:
+            return 0;
+        }
+    }
+
+    static bool hasAdditionalChars(std::string* locale_str, uint16_t c) {
+        return getAdditionalCharsSize(locale_str, c) > 0;
+    }
+};
+
+}
+
+#endif // LATINIME_ADDITIONAL_PROXIMITY_CHARS_H