/*
 *  Copyright (c) 2014, Oculus VR, Inc.
 *  All rights reserved.
 *
 *  This source code is licensed under the BSD-style license found in the
 *  LICENSE file in the root directory of this source tree. An additional grant 
 *  of patent rights can be found in the PATENTS file in the same directory.
 *
 */

#ifndef __RAK_STRING_H
#define __RAK_STRING_H 

#include "Export.h"
#include "DS_List.h"
#include "RakNetTypes.h" // int64_t
#include <stdio.h>
#include "stdarg.h"


#ifdef _WIN32



#include "WindowsIncludes.h"
#endif

namespace RakNet
{
/// Forward declarations
class SimpleMutex;
class BitStream;

/// \brief String class
/// \details Has the following improvements over std::string
/// -Reference counting: Suitable to store in lists
/// -Variadic assignment operator
/// -Doesn't cause linker errors
class RAK_DLL_EXPORT RakString
{
public:
	// Constructors
	RakString();
	RakString(char input);
	RakString(unsigned char input);
	RakString(const unsigned char *format, ...);
	RakString(const char *format, ...);
	~RakString();
	RakString( const RakString & rhs);

	/// Implicit return of const char*
	operator const char* () const {return sharedString->c_str;}

	/// Same as std::string::c_str
	const char *C_String(void) const {return sharedString->c_str;}

	// Lets you modify the string. Do not make the string longer - however, you can make it shorter, or change the contents.
	// Pointer is only valid in the scope of RakString itself
	char *C_StringUnsafe(void) {Clone(); return sharedString->c_str;}

	/// Assigment operators
	RakString& operator = ( const RakString& rhs );
	RakString& operator = ( const char *str );
	RakString& operator = ( char *str );
	RakString& operator = ( const unsigned char *str );
	RakString& operator = ( char unsigned *str );
	RakString& operator = ( const char c );

	/// Concatenation
	RakString& operator +=( const RakString& rhs);
	RakString& operator += ( const char *str );
	RakString& operator += ( char *str );
	RakString& operator += ( const unsigned char *str );
	RakString& operator += ( char unsigned *str );
	RakString& operator += ( const char c );

	/// Character index. Do not use to change the string however.
	unsigned char operator[] ( const unsigned int position ) const;

#ifdef _WIN32
	// Return as Wide char
	// Deallocate with DeallocWideChar
	WCHAR * ToWideChar(void);
	void DeallocWideChar(WCHAR * w);

	void FromWideChar(const wchar_t *source);
	static RakNet::RakString FromWideChar_S(const wchar_t *source);
#endif
	
	/// String class find replacement
	/// Searches the string for the content specified in stringToFind and returns the position of the first occurrence in the string.
	/// Search only includes characters on or after position pos, ignoring any possible occurrences in previous locations.
	/// \param[in] stringToFind The string to find inside of this object's string
	/// \param[in] pos The position in the string to start the search
	/// \return Returns the position of the first occurrence in the string.
	size_t Find(const char *stringToFind,size_t pos = 0 );

	/// Equality
	bool operator==(const RakString &rhs) const;
	bool operator==(const char *str) const;
	bool operator==(char *str) const;

	// Comparison
	bool operator < ( const RakString& right ) const;
	bool operator <= ( const RakString& right ) const;
	bool operator > ( const RakString& right ) const;
	bool operator >= ( const RakString& right ) const;

	/// Inequality
	bool operator!=(const RakString &rhs) const;
	bool operator!=(const char *str) const;
	bool operator!=(char *str) const;

	/// Change all characters to lowercase
	const char * ToLower(void);

	/// Change all characters to uppercase
	const char * ToUpper(void);

	/// Set the value of the string
	void Set(const char *format, ...);

	/// Sets a copy of a substring of str as the new content. The substring is the portion of str 
	/// that begins at the character position pos and takes up to n characters 
	/// (it takes less than n if the end of str is reached before).
	/// \param[in] str The string to copy in
	/// \param[in] pos The position on str to start the copy
	/// \param[in] n How many chars to copy
	/// \return Returns the string, note that the current string is set to that value as well
	RakString Assign(const char *str,size_t pos, size_t n );

	/// Returns if the string is empty. Also, C_String() would return ""
	bool IsEmpty(void) const;

	/// Returns the length of the string
	size_t GetLength(void) const;
	size_t GetLengthUTF8(void) const;

	/// Replace character(s) in starting at index, for count, with c
	void Replace(unsigned index, unsigned count, unsigned char c);

	/// Replace character at index with c
	void SetChar( unsigned index, unsigned char c );

	/// Replace character at index with string s
	void SetChar( unsigned index, RakNet::RakString s );

	/// Make sure string is no longer than \a length
	void Truncate(unsigned int length);
	void TruncateUTF8(unsigned int length);

	// Gets the substring starting at index for count characters
	RakString SubStr(unsigned int index, unsigned int count) const;

	/// Erase characters out of the string at index for count
	void Erase(unsigned int index, unsigned int count);

	/// Set the first instance of c with a NULL terminator
	void TerminateAtFirstCharacter(char c);
	/// Set the last instance of c with a NULL terminator
	void TerminateAtLastCharacter(char c);

	void StartAfterFirstCharacter(char c);
	void StartAfterLastCharacter(char c);

	/// Returns how many occurances there are of \a c in the string
	int GetCharacterCount(char c);
	
	/// Remove all instances of c
	void RemoveCharacter(char c);

	/// Create a RakString with a value, without doing printf style parsing
	/// Equivalent to assignment operator
	static RakNet::RakString NonVariadic(const char *str);

	/// Hash the string into an unsigned int
	static unsigned long ToInteger(const char *str);
	static unsigned long ToInteger(const RakString &rs);

	/// \brief Read an integer out of a substring
	/// \param[in] str The string
	/// \param[in] pos The position on str where the integer starts
	/// \param[in] n How many chars to copy
	static int ReadIntFromSubstring(const char *str, size_t pos, size_t n);

	// Like strncat, but for a fixed length
	void AppendBytes(const char *bytes, unsigned int count);

	/// Compare strings (case sensitive)
	int StrCmp(const RakString &rhs) const;

	/// Compare strings (case sensitive), up to num characters
	int StrNCmp(const RakString &rhs, size_t num) const;

	/// Compare strings (not case sensitive)
	int StrICmp(const RakString &rhs) const;

	/// Clear the string
	void Clear(void);

	/// Print the string to the screen
	void Printf(void);

	/// Print the string to a file
	void FPrintf(FILE *fp);

	/// Does the given IP address match the IP address encoded into this string, accounting for wildcards?
	bool IPAddressMatch(const char *IP);

	/// Does the string contain non-printable characters other than spaces?
	bool ContainsNonprintableExceptSpaces(void) const;

	/// Is this a valid email address?
	bool IsEmailAddress(void) const;

	/// URL Encode the string. See http://www.codeguru.com/cpp/cpp/cpp_mfc/article.php/c4029/
	RakNet::RakString& URLEncode(void);

	/// URL decode the string
	RakNet::RakString& URLDecode(void);

	/// https://servers.api.rackspacecloud.com/v1.0 to https://,  servers.api.rackspacecloud.com, /v1.0
	void SplitURI(RakNet::RakString &header, RakNet::RakString &domain, RakNet::RakString &path);

	/// Scan for quote, double quote, and backslash and prepend with backslash
	RakNet::RakString& SQLEscape(void);

	/// Format as a POST command that can be sent to a webserver
	/// \param[in] uri For example, masterserver2.raknet.com/testServer
	/// \param[in] contentType For example, text/plain; charset=UTF-8
	/// \param[in] body Body of the post
	/// \return Formatted string
	static RakNet::RakString FormatForPOST(const char* uri, const char* contentType, const char* body, const char* extraHeaders="");
	static RakNet::RakString FormatForPUT(const char* uri, const char* contentType, const char* body, const char* extraHeaders="");

	/// Format as a GET command that can be sent to a webserver
	/// \param[in] uri For example, masterserver2.raknet.com/testServer?__gameId=comprehensivePCGame
	/// \return Formatted string
	static RakNet::RakString FormatForGET(const char* uri, const char* extraHeaders="");

	/// Format as a DELETE command that can be sent to a webserver
	/// \param[in] uri For example, masterserver2.raknet.com/testServer?__gameId=comprehensivePCGame&__rowId=1
	/// \return Formatted string
	static RakNet::RakString FormatForDELETE(const char* uri, const char* extraHeaders="");

	/// Fix to be a file path, ending with /
	RakNet::RakString& MakeFilePath(void);

	/// RakString uses a freeList of old no-longer used strings
	/// Call this function to clear this memory on shutdown
	static void FreeMemory(void);
	/// \internal
	static void FreeMemoryNoMutex(void);

	/// Serialize to a bitstream, uncompressed (slightly faster)
	/// \param[out] bs Bitstream to serialize to
	void Serialize(BitStream *bs) const;

	/// Static version of the Serialize function
	static void Serialize(const char *str, BitStream *bs);

	/// Serialize to a bitstream, compressed (better bandwidth usage)
	/// \param[out]  bs Bitstream to serialize to
	/// \param[in] languageId languageId to pass to the StringCompressor class
	/// \param[in] writeLanguageId encode the languageId variable in the stream. If false, 0 is assumed, and DeserializeCompressed will not look for this variable in the stream (saves bandwidth)
	/// \pre StringCompressor::AddReference must have been called to instantiate the class (Happens automatically from RakPeer::Startup())
	void SerializeCompressed(BitStream *bs, uint8_t languageId=0, bool writeLanguageId=false) const;

	/// Static version of the SerializeCompressed function
	static void SerializeCompressed(const char *str, BitStream *bs, uint8_t languageId=0, bool writeLanguageId=false);

	/// Deserialize what was written by Serialize
	/// \param[in] bs Bitstream to serialize from
	/// \return true if the deserialization was successful
	bool Deserialize(BitStream *bs);

	/// Static version of the Deserialize() function
	static bool Deserialize(char *str, BitStream *bs);

	/// Deserialize compressed string, written by SerializeCompressed
	/// \param[in] bs Bitstream to serialize from
	/// \param[in] readLanguageId If true, looks for the variable langaugeId in the data stream. Must match what was passed to SerializeCompressed
	/// \return true if the deserialization was successful
	/// \pre StringCompressor::AddReference must have been called to instantiate the class (Happens automatically from RakPeer::Startup())
	bool DeserializeCompressed(BitStream *bs, bool readLanguageId=false);

	/// Static version of the DeserializeCompressed() function
	static bool DeserializeCompressed(char *str, BitStream *bs, bool readLanguageId=false);

	static const char *ToString(int64_t i);
	static const char *ToString(uint64_t i);

	/// \internal
	static size_t GetSizeToAllocate(size_t bytes)
	{
		const size_t smallStringSize = 128-sizeof(unsigned int)-sizeof(size_t)-sizeof(char*)*2;
		if (bytes<=smallStringSize)
			return smallStringSize;
		else
			return bytes*2;
	}

	/// \internal
	struct SharedString
	{
		SimpleMutex *refCountMutex;
		unsigned int refCount;
		size_t bytesUsed;
		char *bigString;
		char *c_str;
		char smallString[128-sizeof(unsigned int)-sizeof(size_t)-sizeof(char*)*2];		
	};

	/// \internal
	RakString( SharedString *_sharedString );

	/// \internal
	SharedString *sharedString;

//	static SimpleMutex poolMutex;
//	static DataStructures::MemoryPool<SharedString> pool;
	/// \internal
	static SharedString emptyString;

	//static SharedString *sharedStringFreeList;
	//static unsigned int sharedStringFreeListAllocationCount;
	/// \internal
	/// List of free objects to reduce memory reallocations
	static DataStructures::List<SharedString*> freeList;

	static int RakStringComp( RakString const &key, RakString const &data );

	static void LockMutex(void);
	static void UnlockMutex(void);

protected:
	static RakNet::RakString FormatForPUTOrPost(const char* type, const char* uri, const char* contentType, const char* body, const char* extraHeaders);
	void Allocate(size_t len);
	void Assign(const char *str);
	void Assign(const char *str, va_list ap);
	
	void Clone(void);
	void Free(void);
	unsigned char ToLower(unsigned char c);
	unsigned char ToUpper(unsigned char c);
	void Realloc(SharedString *sharedString, size_t bytes);
};

}

const RakNet::RakString RAK_DLL_EXPORT operator+(const RakNet::RakString &lhs, const RakNet::RakString &rhs);


#endif