refactor: finish Windows encoding namespace.

- finish Windows encoding namespace. - add std::expected polyfill for help.
2025-07-14 15:06:33 +08:00
parent fa52d7416f
commit 3605151caf
8 changed files with 425 additions and 56 deletions
--- a/src/yycc/encoding/windows.hpp
+++ b/src/yycc/encoding/windows.hpp
@ -0,0 +1,80 @@
+#pragma once
+#include "../macro/os_detector.hpp"
+#include "../string.hpp"
+#include "../patch/expected.hpp"
+#include <cstdint>
+
+#define NS_YYCC_STRING ::yycc::string
+#define NS_YYCC_PATCH_EXPECTED ::yycc::patch::expected
+
+namespace yycc::encoding::windows {
+
+#if YYCC_OS == YYCC_OS_WINDOWS
+
+    using CodePage = uint32_t;
+
+    /// @private
+    enum class ConvError {
+        TooLargeLength, ///< The length of given string is too large exceeding the maximum capacity of Win32 function.
+        NoDesiredSize, ///< Can not compute the desired size of result string.
+        BadWrittenSize, ///< The size of written data is not matched with expected size.
+    };
+
+    /// @private
+    template<typename T>
+    using ConvResult = NS_YYCC_PATCH_EXPECTED::Expected<T, ConvError>;
+
+    // WChar -> Char
+    ConvResult<std::string> priv_to_char(const std::wstring_view& src, CodePage code_page);
+    bool to_char(const std::wstring_view& src, std::string& dst, CodePage code_page);
+    std::string to_char(const std::wstring_view& src, CodePage code_page);
+
+    // Char -> WChar
+    ConvResult<std::wstring> priv_to_wchar(const std::string_view& src, CodePage code_page);
+    bool to_wchar(const std::string_view& src, std::wstring& dst, CodePage code_page);
+    std::wstring to_wchar(const std::string_view& src, CodePage code_page);
+
+    // YYC MARK:
+    // Following functions are basically the alias of above functions.
+
+    // Char -> Char
+    ConvResult<std::string> priv_to_char(const std::string_view& src,
+                                         CodePage src_code_page,
+                                         CodePage dst_code_page);
+    bool to_char(const std::string_view& src,
+                 std::string& dst,
+                 CodePage src_code_page,
+                 CodePage dst_code_page);
+    std::string to_char(const std::string_view& src, CodePage src_code_page, CodePage dst_code_page);
+
+    // YYC MARK:
+    // Following functions are basically the specialized UTF8 functions.
+
+    // WChar -> UTF8
+    ConvResult<NS_YYCC_STRING::u8string> priv_to_utf8(const std::wstring_view& src);
+    bool to_utf8(const std::wstring_view& src, NS_YYCC_STRING::u8string& dst);
+    NS_YYCC_STRING::u8string to_utf8(const std::wstring_view& src);
+
+    // UTF8 -> WChar
+    ConvResult<std::wstring> priv_to_wchar(const NS_YYCC_STRING::u8string_view& src);
+    bool to_wchar(const NS_YYCC_STRING::u8string_view& src, std::wstring& dst);
+    std::wstring to_wchar(const NS_YYCC_STRING::u8string_view& src);
+
+    // Char -> UTF8
+    ConvResult<NS_YYCC_STRING::u8string> priv_to_utf8(const std::string_view& src,
+                                                      CodePage code_page);
+    bool to_utf8(const std::string_view& src, NS_YYCC_STRING::u8string& dst, CodePage code_page);
+    NS_YYCC_STRING::u8string to_utf8(const std::string_view& src, CodePage code_page);
+
+    // UTF8 -> Char
+    ConvResult<std::string> priv_to_char(const NS_YYCC_STRING::u8string_view& src,
+                                         CodePage code_page);
+    bool to_char(const NS_YYCC_STRING::u8string_view& src, std::string& dst, CodePage code_page);
+    std::string to_char(const NS_YYCC_STRING::u8string_view& src, CodePage code_page);
+
+#endif
+
+} // namespace yycc::encoding::windows
+
+#undef NS_YYCC_PATCH_EXPECTED
+#undef NS_YYCC_STRING