//********************************** Banshee Engine (www.banshee3d.com) **************************************************//
//**************** Copyright (c) 2016 Marko Pintera (marko.pintera@gmail.com). All rights reserved. **********************//
#pragma once

#include "BsEditorPrerequisites.h"
#include "GUI/BsGUIElementContainer.h"

namespace bs
{
	/** @addtogroup GUI-Editor
	 *  @{
	 */

	/**
	 * A composite GUI object representing an editor field. Editor fields are a combination of a label and an input field.
	 * Label is optional. This specific implementation displays a list box field.
	 */
	class BS_ED_EXPORT GUIListBoxField : public GUIElementContainer
	{
		struct PrivatelyConstruct {};

	public:
		/** Returns type name of the GUI element used for finding GUI element styles. */
		static const String& getGUITypeName();

		/** Returns style type name of the internal GUILabel element. */
		static const String& getLabelStyleType();

		/** Style type name for the internal list box. */
		static const String& getListBoxStyleType();

		/**
		 * Creates a new GUI list box field with a label.
		 *
		 * @param[in]	elements		Elements to display in the list box.
		 * @param[in]	multiselect		Determines should the listbox allow multiple elements to be selected or just one.
		 * @param[in]	labelContent	Content to display in the editor field label.
		 * @param[in]	labelWidth		Width of the label in pixels.
		 * @param[in]	options			Options that allow you to control how is the element positioned and sized.
		 *								This will override any similar options set by style.
		 * @param[in]	style			Optional style to use for the element. Style will be retrieved from GUISkin of the
		 *								GUIWidget the element is used on. If not specified default style is used.
		 */
		static GUIListBoxField* create(const Vector<HString>& elements, bool multiselect, const GUIContent& labelContent, 
			UINT32 labelWidth, const GUIOptions& options, const String& style = StringUtil::BLANK);

		/**
		 * Creates a new GUI list box field with a label.
		 *
		 * @param[in]	elements		Elements to display in the list box.
		 * @param[in]	multiselect		Determines should the listbox allow multiple elements to be selected or just one.
		 * @param[in]	labelContent	Content to display in the editor field label.
		 * @param[in]	options			Options that allow you to control how is the element positioned and sized.
		 *								This will override any similar options set by style.
		 * @param[in]	style			Optional style to use for the element. Style will be retrieved from GUISkin of the
		 *								GUIWidget the element is used on. If not specified default style is used.
		 */
		static GUIListBoxField* create(const Vector<HString>& elements, bool multiselect, const GUIContent& labelContent,
			const GUIOptions& options, const String& style = StringUtil::BLANK);

		/**
		 * Creates a new GUI list box field with a label.
		 *
		 * @param[in]	elements		Elements to display in the list box.
		 * @param[in]	multiselect		Determines should the listbox allow multiple elements to be selected or just one.
		 * @param[in]	labelText		String to display in the editor field label.
		 * @param[in]	labelWidth		Width of the label in pixels.
		 * @param[in]	options			Options that allow you to control how is the element positioned and sized.
		 *								This will override any similar options set by style.
		 * @param[in]	style			Optional style to use for the element. Style will be retrieved from GUISkin of the
		 *								GUIWidget the element is used on. If not specified default style is used.
		 */
		static GUIListBoxField* create(const Vector<HString>& elements, bool multiselect, const HString& labelText, 
			UINT32 labelWidth, const GUIOptions& options, const String& style = StringUtil::BLANK);

		/**
		 * Creates a new GUI list box field with a label.
		 *
		 * @param[in]	elements		Elements to display in the list box.
		 * @param[in]	multiselect		Determines should the listbox allow multiple elements to be selected or just one.
		 * @param[in]	labelText		String to display in the editor field label.
		 * @param[in]	options			Options that allow you to control how is the element positioned and sized.
		 *								This will override any similar options set by style.
		 * @param[in]	style			Optional style to use for the element. Style will be retrieved from GUISkin of the
		 *								GUIWidget the element is used on. If not specified default style is used.
		 */
		static GUIListBoxField* create(const Vector<HString>& elements, bool multiselect, const HString& labelText, 
			const GUIOptions& options, const String& style = StringUtil::BLANK);

		/**
		 * Creates a new GUI list box field without a label.
		 *
		 * @param[in]	elements		Elements to display in the list box.
		 * @param[in]	multiselect		Determines should the listbox allow multiple elements to be selected or just one.
		 * @param[in]	options			Options that allow you to control how is the element positioned and sized.
		 *								This will override any similar options set by style.
		 * @param[in]	style			Optional style to use for the element. Style will be retrieved from GUISkin of the
		 *								GUIWidget the element is used on. If not specified default style is used.
		 */
		static GUIListBoxField* create(const Vector<HString>& elements, bool multiselect, const GUIOptions& options,
			const String& style = StringUtil::BLANK);

		/**
		 * Creates a new GUI list box field with a label.
		 *
		 * @param[in]	elements		Elements to display in the list box.
		 * @param[in]	multiselect		Determines should the listbox allow multiple elements to be selected or just one.
		 * @param[in]	labelContent	Content to display in the editor field label.
		 * @param[in]	labelWidth		Width of the label in pixels.
		 * @param[in]	style			Optional style to use for the element. Style will be retrieved from GUISkin of the
		 *								GUIWidget the element is used on. If not specified default style is used.
		 */
		static GUIListBoxField* create(const Vector<HString>& elements, bool multiselect, const GUIContent& labelContent,
			UINT32 labelWidth, const String& style = StringUtil::BLANK);

		/**
		 * Creates a new GUI list box field with a label.
		 *
		 * @param[in]	elements		Elements to display in the list box.
		 * @param[in]	multiselect		Determines should the listbox allow multiple elements to be selected or just one.
		 * @param[in]	labelContent	Content to display in the editor field label.
		 * @param[in]	style			Optional style to use for the element. Style will be retrieved from GUISkin of the
		 *								GUIWidget the element is used on. If not specified default style is used.
		 */
		static GUIListBoxField* create(const Vector<HString>& elements, bool multiselect, const GUIContent& labelContent,
			const String& style = StringUtil::BLANK);

		/**
		 * Creates a new GUI list box field with a label.
		 *
		 * @param[in]	elements		Elements to display in the list box.
		 * @param[in]	multiselect		Determines should the listbox allow multiple elements to be selected or just one.
		 * @param[in]	labelText		String to display in the editor field label.
		 * @param[in]	labelWidth		Width of the label in pixels.
		 * @param[in]	style			Optional style to use for the element. Style will be retrieved from GUISkin of the
		 *								GUIWidget the element is used on. If not specified default style is used.
		 */
		static GUIListBoxField* create(const Vector<HString>& elements, bool multiselect, const HString& labelText, 
			UINT32 labelWidth, const String& style = StringUtil::BLANK);

		/**
		 * Creates a new GUI list box field with a label.
		 *
		 * @param[in]	elements		Elements to display in the list box.
		 * @param[in]	multiselect		Determines should the listbox allow multiple elements to be selected or just one.
		 * @param[in]	labelText		String to display in the editor field label.
		 * @param[in]	style			Optional style to use for the element. Style will be retrieved from GUISkin of the
		 *								GUIWidget the element is used on. If not specified default style is used.
		 */
		static GUIListBoxField* create(const Vector<HString>& elements, bool multiselect, const HString& labelText,
			const String& style = StringUtil::BLANK);

		/**
		 * Creates a new GUI list box field without a label.
		 *
		 * @param[in]	elements		Elements to display in the list box.
		 * @param[in]	multiselect		Determines should the listbox allow multiple elements to be selected or just one.
		 * @param[in]	style			Optional style to use for the element. Style will be retrieved from GUISkin of the
		 *								GUIWidget the element is used on. If not specified default style is used.
		 */
		static GUIListBoxField* create(const Vector<HString>& elements, bool multiselect, 
			const String& style = StringUtil::BLANK);

		GUIListBoxField(const PrivatelyConstruct& dummy, const Vector<HString>& elements, bool multiselect, 
			const GUIContent& labelContent, UINT32 labelWidth, const String& style, const GUIDimensions& dimensions, bool withLabel);

		/**	Checks whether the listbox supports multiple selected elements at once. */
		bool isMultiselect() const;

		/**	Changes the list box elements. */
		void setElements(const Vector<HString>& elements);

		/**	Selects an element with the specified index. */
		void selectElement(UINT32 value);

		/**	Deselect element the element with the specified index. Only relevant for multi-select list boxes. */
		void deselectElement(UINT32 idx);

		/**	Returns states of all element in the list box (enabled or disabled). */
		const Vector<bool>& getElementStates() const;

		/**
		 * Sets states for all list box elements. Only valid for multi-select list boxes. Number of states must match number
		 * of list box elements.
		 */
		void setElementStates(const Vector<bool>& states);

		/** @copydoc GUIElement::setTint */
		void setTint(const Color& color) override;

		/** Triggers when a new element is selected. Provides index to the element. */
		Event<void(UINT32, bool)> onSelectionChanged; 
	protected:
		static const UINT32 DEFAULT_LABEL_WIDTH;

		virtual ~GUIListBoxField();

		/** @copydoc GUIElement::_updateLayoutInternal */
		void _updateLayoutInternal(const GUILayoutData& data) override;

		/** @copydoc GUIElement::_getOptimalSize */
		Vector2I _getOptimalSize() const override;

		/** @copydoc GUIElement::styleUpdated */
		void styleUpdated() override;

		/**	Triggered when the selected list box element changes. */
		void selectionChanged(UINT32 newIndex, bool enabled);

		GUIListBox* mListBox;
		GUILayout* mLayout;
		GUILabel* mLabel;
	};

	/** @} */
}