From e68e0d9a5130e8bc0b634572b7fd44b9bfc0f8ef Mon Sep 17 00:00:00 2001
From: crupest <crupest@outlook.com>
Date: Sat, 30 Oct 2021 21:08:43 +0800
Subject: ...

---
 src/common/StringUtil.cpp | 59 +++++------------------------------------------
 1 file changed, 6 insertions(+), 53 deletions(-)

(limited to 'src/common/StringUtil.cpp')

diff --git a/src/common/StringUtil.cpp b/src/common/StringUtil.cpp
index b1f1ed4b..7492bdfd 100644
--- a/src/common/StringUtil.cpp
+++ b/src/common/StringUtil.cpp
@@ -1,15 +1,10 @@
 #include "cru/common/StringUtil.hpp"
+#include <functional>
 #include "cru/common/Base.hpp"
 #include "cru/common/Exception.hpp"
 
 namespace cru {
-namespace {
-template <typename UInt, int number_of_bit, typename ReturnType>
-inline std::enable_if_t<std::is_unsigned_v<UInt>, ReturnType> ExtractBits(
-    UInt n) {
-  return static_cast<ReturnType>(n & ((1u << number_of_bit) - 1));
-}
-}  // namespace
+using details::ExtractBits;
 
 CodePoint Utf8NextCodePoint(std::string_view str, Index current,
                             Index* next_position) {
@@ -154,57 +149,15 @@ CodePoint Utf16PreviousCodePoint(std::u16string_view str, Index current,
 }
 
 void Utf8EncodeCodePointAppend(CodePoint code_point, std::string& str) {
-  auto write_continue_byte = [&str](std::uint8_t byte6) {
-    str.push_back((1u << 7) + (((1u << 6) - 1) & byte6));
-  };
-
-  if (code_point >= 0 && code_point <= 0x007F) {
-    str.push_back(static_cast<char>(code_point));
-  } else if (code_point >= 0x0080 && code_point <= 0x07FF) {
-    std::uint32_t unsigned_code_point = code_point;
-    str.push_back(static_cast<char>(ExtractBits<std::uint32_t, 5, std::uint8_t>(
-                                        (unsigned_code_point >> 6)) +
-                                    0b11000000));
-    write_continue_byte(
-        ExtractBits<std::uint32_t, 6, std::uint8_t>(unsigned_code_point));
-  } else if (code_point >= 0x0800 && code_point <= 0xFFFF) {
-    std::uint32_t unsigned_code_point = code_point;
-    str.push_back(static_cast<char>(ExtractBits<std::uint32_t, 4, std::uint8_t>(
-                                        (unsigned_code_point >> (6 * 2))) +
-                                    0b11100000));
-    write_continue_byte(
-        ExtractBits<std::uint32_t, 6, std::uint8_t>(unsigned_code_point >> 6));
-    write_continue_byte(
-        ExtractBits<std::uint32_t, 6, std::uint8_t>(unsigned_code_point));
-  } else if (code_point >= 0x10000 && code_point <= 0x10FFFF) {
-    std::uint32_t unsigned_code_point = code_point;
-    str.push_back(static_cast<char>(ExtractBits<std::uint32_t, 3, std::uint8_t>(
-                                        (unsigned_code_point >> (6 * 3))) +
-                                    0b11110000));
-    write_continue_byte(ExtractBits<std::uint32_t, 6, std::uint8_t>(
-        unsigned_code_point >> (6 * 2)));
-    write_continue_byte(
-        ExtractBits<std::uint32_t, 6, std::uint8_t>(unsigned_code_point >> 6));
-    write_continue_byte(
-        ExtractBits<std::uint32_t, 6, std::uint8_t>(unsigned_code_point));
-  } else {
+  if (!Utf8EncodeCodePointAppendWithFunc(code_point,
+                                         [&str](char c) { str.push_back(c); }))
     throw TextEncodeException(u"Code point out of range.");
-  }
 }
 
 void Utf16EncodeCodePointAppend(CodePoint code_point, std::u16string& str) {
-  if ((code_point >= 0 && code_point <= 0xD7FF) ||
-      (code_point >= 0xE000 && code_point <= 0xFFFF)) {
-    str.push_back(static_cast<char16_t>(code_point));
-  } else if (code_point >= 0x10000 && code_point <= 0x10FFFF) {
-    std::uint32_t u = code_point - 0x10000;
-    str.push_back(static_cast<char16_t>(
-        ExtractBits<std::uint32_t, 10, std::uint32_t>(u >> 10) + 0xD800u));
-    str.push_back(static_cast<char16_t>(
-        ExtractBits<std::uint32_t, 10, std::uint32_t>(u) + 0xDC00u));
-  } else {
+  if (!Utf16EncodeCodePointAppendWithFunc(
+          code_point, [&str](char16_t c) { str.push_back(c); }))
     throw TextEncodeException(u"Code point out of range.");
-  }
 }
 
 std::string ToUtf8(std::u16string_view s) {
-- 
cgit v1.2.3