From e3daf7ef1fdb6b9d31a4eeaf343630ccbeb4a4b0 Mon Sep 17 00:00:00 2001
From: Lynix <lynix680@gmail.com>
Date: Sat, 3 Dec 2016 00:34:55 +0100
Subject: [PATCH] Core/String: Add GetCharacterPosition method

---
 include/Nazara/Core/String.hpp |  1 +
 src/Nazara/Core/String.cpp     | 39 +++++++++++++++++++++++++++++++++-
 2 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/include/Nazara/Core/String.hpp b/include/Nazara/Core/String.hpp
index 765ef8b85..ba7f34ff7 100644
--- a/include/Nazara/Core/String.hpp
+++ b/include/Nazara/Core/String.hpp
@@ -82,6 +82,7 @@ namespace Nz
 
 			char* GetBuffer();
 			std::size_t GetCapacity() const;
+			std::size_t GetCharacterPosition(std::size_t characterIndex) const;
 			const char* GetConstBuffer() const;
 			std::size_t GetLength() const;
 			std::size_t GetSize() const;
diff --git a/src/Nazara/Core/String.cpp b/src/Nazara/Core/String.cpp
index 5019f0885..ac01bf92c 100644
--- a/src/Nazara/Core/String.cpp
+++ b/src/Nazara/Core/String.cpp
@@ -2094,6 +2094,43 @@ namespace Nz
 		return m_sharedString->capacity;
 	}
 
+	/*!
+	* \brief Gets the index where a character begin
+	*
+	* Iterate through the string to find the starting position of a specific character index
+	* This is useful because non-ASCII characters may be encoded using multiple bytes.
+	*
+	* \param characterIndex Index of the character to search for
+	*
+	* \return Starting index
+	*/
+	std::size_t String::GetCharacterPosition(std::size_t characterIndex) const
+	{
+		const char* ptr = m_sharedString->string.get();
+		const char* end = &m_sharedString->string[m_sharedString->size];
+
+		try
+		{
+			utf8::advance(ptr, characterIndex, end);
+
+			return ptr - m_sharedString->string.get();
+		}
+		catch (utf8::not_enough_room& e)
+		{
+			// Returns npos
+		}
+		catch (utf8::exception& e)
+		{
+			NazaraError("UTF-8 error: " + String(e.what()));
+		}
+		catch (std::exception& e)
+		{
+			NazaraError(e.what());
+		}
+
+		return npos;
+	}
+
 	/*!
 	* \brief Gets the raw buffer
 	* \return Raw buffer
@@ -5948,7 +5985,7 @@ namespace std
 
 		char c;
 
-		for (;;) 
+		for (;;)
 		{
 			is.get(c);
 			if (c != delim && c != '\0')