TextArea.hpp

//
// TGUI - Texus' Graphical User Interface
// Copyright (C) 2012-2025 Bruno Van de Velde (vdv_b@tgui.eu)
//
// This software is provided 'as-is', without any express or implied warranty.
// In no event will the authors be held liable for any damages arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it freely,
// subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented;
//    you must not claim that you wrote the original software.
//    If you use this software in a product, an acknowledgment
//    in the product documentation would be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such,
//    and must not be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//
 
#ifndef TGUI_TEXT_AREA_HPP
#define TGUI_TEXT_AREA_HPP
 
#include <TGUI/Widgets/Scrollbar.hpp>
#include <TGUI/Renderers/TextAreaRenderer.hpp>
#include <TGUI/Text.hpp>

 
TGUI_MODULE_EXPORT namespace tgui
{
    class TGUI_API TextArea : public Widget, public DualScrollbarChildInterface
    {
    public:
 
        using Ptr = std::shared_ptr<TextArea>; 
        using ConstPtr = std::shared_ptr<const TextArea>; 
 
        static constexpr const char StaticWidgetType[] = "TextArea"; 

        TextArea(const char* typeName = StaticWidgetType, bool initRenderer = true);

        TGUI_NODISCARD static TextArea::Ptr create();

        TGUI_NODISCARD static TextArea::Ptr copy(const TextArea::ConstPtr& textArea);

        TGUI_NODISCARD TextAreaRenderer* getSharedRenderer() override;
        TGUI_NODISCARD const TextAreaRenderer* getSharedRenderer() const override;

        TGUI_NODISCARD TextAreaRenderer* getRenderer() override;

        void setSize(const Layout2d& size) override;
        using Widget::setSize;

        void setText(String text);

        void addText(String text);

        TGUI_NODISCARD String getText() const;

        void setDefaultText(const String& text);

        TGUI_NODISCARD const String& getDefaultText() const;

        void setSelectedText(std::size_t selectionStartIndex, std::size_t selectionEndIndex);

        TGUI_NODISCARD String getSelectedText() const;

        TGUI_NODISCARD std::size_t getSelectionStart() const;

        TGUI_NODISCARD std::size_t getSelectionEnd() const;

        void setMaximumCharacters(std::size_t maxChars = 0);

        TGUI_NODISCARD std::size_t getMaximumCharacters() const;

        void setTabString(String tabText);

        TGUI_NODISCARD String getTabString() const;

        void setCaretPosition(std::size_t charactersBeforeCaret);

        TGUI_NODISCARD std::size_t getCaretPosition() const;

        TGUI_NODISCARD std::size_t getCaretLine() const;

        TGUI_NODISCARD std::size_t getCaretColumn() const;

        void setReadOnly(bool readOnly = true);

        TGUI_NODISCARD bool isReadOnly() const;

        TGUI_DEPRECATED("Use getVerticalScrollbar->setPolicy(policy) instead") void setVerticalScrollbarPolicy(Scrollbar::Policy policy);

        TGUI_DEPRECATED("Use getVerticalScrollbar->getPolicy() instead") TGUI_NODISCARD Scrollbar::Policy getVerticalScrollbarPolicy() const;

        TGUI_DEPRECATED("Use getHorizontalScrollbar->setPolicy(policy) instead") void setHorizontalScrollbarPolicy(Scrollbar::Policy policy);

        TGUI_DEPRECATED("Use getHorizontalScrollbar->getPolicy() instead") TGUI_NODISCARD Scrollbar::Policy getHorizontalScrollbarPolicy() const;

        TGUI_NODISCARD std::size_t getLinesCount() const;

        void setFocused(bool focused) override;

        void enableMonospacedFontOptimization(bool enable = true);

        TGUI_DEPRECATED("Use getVerticalScrollbar->setValue(value) instead") void setVerticalScrollbarValue(unsigned int value);

        TGUI_DEPRECATED("Use getVerticalScrollbar->getValue() instead") TGUI_NODISCARD unsigned int getVerticalScrollbarValue() const;

        TGUI_DEPRECATED("Use getVerticalScrollbar->getMaxValue() instead") TGUI_NODISCARD unsigned int getVerticalScrollbarMaxValue() const;

        TGUI_DEPRECATED("Use getHorizontalScrollbar->setValue(value) instead") void setHorizontalScrollbarValue(unsigned int value);

        TGUI_DEPRECATED("Use getHorizontalScrollbar->getValue() instead") TGUI_NODISCARD unsigned int getHorizontalScrollbarValue() const;

        TGUI_DEPRECATED("Use getHorizontalScrollbar->getMaxValue() instead") TGUI_NODISCARD unsigned int getHorizontalScrollbarMaxValue() const;

        TGUI_NODISCARD bool isMouseOnWidget(Vector2f pos) const override;

        bool leftMousePressed(Vector2f pos) override;

        void leftMouseReleased(Vector2f pos) override;

        void mouseMoved(Vector2f pos) override;

        void keyPressed(const Event::KeyEvent& event) override;

        bool canHandleKeyPress(const Event::KeyEvent& event) override;

        void textEntered(char32_t key) override;

        bool scrolled(float delta, Vector2f pos, bool touch) override;

        void mouseNoLongerOnWidget() override;

        void leftMouseButtonNoLongerDown() override;

    protected:

        // This function will search after which character the caret should be placed. It will not change the caret position.
        TGUI_NODISCARD Vector2<std::size_t> findCaretPosition(Vector2f position) const;

        // Gets the index of either m_selStart or m_selEnd
        TGUI_NODISCARD std::size_t getIndexOfSelectionPos(Vector2<std::size_t> selectionPos) const;

        // Removes the selected characters. This function is called when pressing backspace, delete or a letter while there were
        // some characters selected.
        void deleteSelectedCharacters();

        // Inserts text at the current caret position.
        // If the given string exceeds the maximum character limit,
        // excess characters from the right side of the string will not be inserted.
        void insertTextAtCaretPosition(String text);

        // Rearrange the text inside the text area (by using word wrap).
        void rearrangeText(bool keepSelection, const bool emitCaretChangedPosition = true);

        // Updates the physical size of the scrollbars, as well as the viewport size.
        void updateScrollbars();

        // This function will split the text into five pieces so that the text can be easily drawn.
        void updateSelectionTexts();

        // Handles "Backspace" key press
        void backspaceKeyPressed();

        // Handles "Delete" key press
        void deleteKeyPressed();

        // Handles "Ctrl+C" key press (or equivalent on macOS)
        void copySelectedTextToClipboard();

        // Handles "Ctrl+X" key press (or equivalent on macOS)
        void cutSelectedTextToClipboard();

        // Handles "Ctrl+V" key press (or equivalent on macOS)
        void pasteTextFromClipboard();

        // Handles "Ctrl+A" key press (or equivalent on macOS)
        void selectAllText();

        // Handles "PageUp" key press
        void moveCaretPageUp();

        // Handles "PageDown" key press
        void moveCaretPageDown();

        // Handles "ArrowLeft" key press
        void moveCaretLeft(bool shiftPressed);

        // Handles "ArrowRight" key press
        void moveCaretRight(bool shiftPressed);

        // Handles "Ctrl+ArrowLeft" key press (or equivalent on macOS)
        void moveCaretWordBegin();

        // Handles "Ctrl+ArrowRight" key press (or equivalent on macOS)
        void moveCaretWordEnd();

        void draw(BackendRenderTarget& target, RenderStates states) const override;

    private:

        // Implementation of setCaretPosition() that either updates or retains the m_selEnd value.
        void setCaretPositionImpl(std::size_t charactersBeforeCaret, bool selEndNeedUpdate, bool emitCaretChangedPosition);

    protected:

        // Returns the size without the borders
        TGUI_NODISCARD Vector2f getInnerSize() const;

        // This function is called every frame with the time passed since the last frame.
        bool updateTime(Duration elapsedTime) override;

        // Recalculates the positions of the contents of the text area.
        void recalculatePositions();

        // Recalculates which lines are currently visible.
        void recalculateVisibleLines();

        TGUI_NODISCARD Signal& getSignal(String signalName) override;

        void rendererChanged(const String& property) override;

        TGUI_NODISCARD std::unique_ptr<DataIO::Node> save(SavingRenderersMap& renderers) const override;

        void load(const std::unique_ptr<DataIO::Node>& node, const LoadingRenderersMap& renderers) override;

        void updateTextSize() override;

        void scrollbarPolicyChanged(Orientation orientation) override;

        // Makes a copy of the widget
        TGUI_NODISCARD Widget::Ptr clone() const override;

        // Updates m_selEnd with a new value and emits the onCaretPositionChange signal
        // @param newValue the value to assign to m_selEnd.
        void updateSelEnd(const Vector2<std::size_t>& newValue);

    public:
 
        SignalString onTextChange = {"TextChanged"};             
        Signal onSelectionChange = {"SelectionChanged"};         
        Signal onCaretPositionChange = {"CaretPositionChanged"}; 

    protected:
 
        String m_text;
        float m_lineHeight = 24;
 
        // The width of the largest line
        float m_maxLineWidth = 0;
 
        std::vector<String> m_lines;
 
        // The maximum characters (0 by default, which means no limit)
        std::size_t m_maxChars = 0;
 
        // What is known about the visible lines?
        std::size_t m_topLine = 1;
        std::size_t m_visibleLines = 1;
 
        // Information about the selection
        Vector2<std::size_t> m_selStart;
        Vector2<std::size_t> m_selEnd;
        std::pair<Vector2<std::size_t>, Vector2<std::size_t>> m_lastSelection;
 
        // Information about the caret
        Vector2f m_caretPosition;
        bool m_caretVisible = true;
 
        // The text to insert when Tab is pressed
        String m_tabText = U"\t";
 
        Text m_textBeforeSelection;
        Text m_textSelection1;
        Text m_textSelection2;
        Text m_textAfterSelection1;
        Text m_textAfterSelection2;
        Text m_defaultText;
 
        std::vector<FloatRect> m_selectionRects;
 
        // Is there a possibility that the user is going to double click?
        bool m_possibleDoubleClick = false;
 
        bool m_readOnly = false;
 
        bool m_monospacedFontOptimizationEnabled = false;
 
        Sprite m_spriteBackground;
 
        // Cached renderer properties
        Borders m_bordersCached;
        Padding m_paddingCached;
        Color   m_borderColorCached;
        Color   m_backgroundColorCached;
        Color   m_caretColorCached;
        Color   m_selectedTextBackgroundColorCached;
        float   m_caretWidthCached = 1;

    };

}

 
#endif // TGUI_TEXT_AREA_HPP