BansheeEngine/Source/BansheeCore/Localization/BsHString.h

//********************************** Banshee Engine (www.banshee3d.com) **************************************************//
//**************** Copyright (c) 2016 Marko Pintera ([email protected]). All rights reserved. **********************//
#pragma once

namespace bs
{
	/** @addtogroup Localization
	 *  @{
	 */

	/**
	 * String handle. Provides a wrapper around an Unicode string, primarily for localization purposes.
	 * 			
	 * Actual value for this string is looked up in a global string table based on the provided identifier string and 
	 * currently active language. If such value doesn't exist then the identifier is used as is.
	 *			
	 * Use {0}, {1}, etc. in the string value for values that might change dynamically.
	 */
	class BS_CORE_EXPORT HString
	{
	public:
		/**
		 * Creates a new localized string with the specified identifier. If the identifier doesn't previously exist in the 
		 * string table, identifier value will also be used for initializing the default language version of the string.
		 *
		 * @param[in]	identifier		String you can use for later referencing the localized string.
		 * @param[in]	stringTableId	Unique identifier of the string table to retrieve the string from.
		 */
		explicit HString(const WString& identifier, UINT32 stringTableId = 0);

		/**
		 * Creates a new localized string with the specified identifier and sets the default language version of the 
		 * string. If a string with that identifier already exists default language string will be updated.
		 *
		 * @param[in]	identifier		String you can use for later referencing the localized string.
		 * @param[in]	defaultString	Default string to assign to the specified identifier. Language to which it will be 
		 *								assigned depends on the StringTable::DEFAULT_LANGUAGE value.
		 * @param[in]	stringTableId	Unique identifier of the string table to retrieve the string from.
		 */
		explicit HString(const WString& identifier, const WString& defaultString, UINT32 stringTableId = 0);

		/**
		 * Creates a new empty localized string.
		 *
		 * @param[in]	stringTableId	Unique identifier of the string table to retrieve the string from.
		 */
		HString(UINT32 stringTableId = 0);
		HString(const HString& copy);
		~HString();

		HString& operator=(const HString& rhs);

		operator const WString& () const;
		const WString& getValue() const;

		/**
		 * Sets a value of a string parameter. Parameters are specified as bracketed values within the string itself 
		 * (for example {0}, {1}) etc. Use ^ as an escape character.
		 *
		 * @note	This is useful for strings that have dynamically changing values, like numbers, embedded in them.
		 */
		void setParameter(UINT32 idx, const WString& value);
		
		/** Returns an empty string. */
		static const HString& dummy();
	private:
		SPtr<LocalizedStringData> mStringData;
		WString* mParameters;

		mutable bool mIsDirty;
		mutable WString mCachedString;
		mutable WString* mStringPtr;
	};

	/** @} */
}