include/rive/text/text.hpp

#ifndef _RIVE_TEXT_CORE_HPP_
#define _RIVE_TEXT_CORE_HPP_
#include "rive/generated/text/text_base.hpp"
#include "rive/math/aabb.hpp"
#include "rive/text/text_value_run.hpp"
#include "rive/text_engine.hpp"
#include "rive/shapes/shape_paint_path.hpp"
#include "rive/simple_array.hpp"
#include "rive/text/glyph_lookup.hpp"
#include "rive/text/text_interface.hpp"
#include "rive/data_bind/data_bind_list_item_consumer.hpp"
#include "rive/viewmodel/symbol_type.hpp"
#include "rive/viewmodel/viewmodel_instance.hpp"
#include "rive/viewmodel/viewmodel_instance_value.hpp"
#include "rive/viewmodel/property_symbol_dependent.hpp"
#include "rive/dirtyable.hpp"
#include "rive/enums.hpp"

#include <functional>
#include <unordered_map>
#include <vector>

namespace rive
{

class Factory;
class Renderer;
class TextModifierGroup;
class TextStylePaint;
class LayoutParticipant;
class TextSelectionController;

// A draw command for interleaving monochrome style paths and color glyphs.
struct TextDrawCommand
{
    enum Type
    {
        kStylePath,
        kColorGlyph
    };
    Type type;
    TextStylePaint* style = nullptr; // for kStylePath

    struct ColorGlyphInfo
    {
        rcp<Font> font;
        GlyphID glyphId;
        Mat2D transform;
        ColorInt foregroundColor;
        float opacity;
    };
    ColorGlyphInfo colorGlyph; // for kColorGlyph
};

class StyledText
{
private:
    /// Represents the unicode characters making up the entire text string
    /// displayed. Only valid after update.
    std::vector<Unichar> m_value;
    std::vector<TextRun> m_runs;

public:
    bool empty() const;
    void clear();
    void append(rcp<Font> font,
                float size,
                float lineHeight,
                float letterSpacing,
                const std::string& text,
                uint16_t styleId);
    const std::vector<Unichar>& unichars() const { return m_value; }
    const std::vector<TextRun>& runs() const { return m_runs; }

    void swapRuns(std::vector<TextRun>& otherRuns) { m_runs.swap(otherRuns); }
};

struct TextBoundsInfo
{
    float minY;
    float maxWidth;
    float totalHeight;
    int ellipsisLine;
    bool isEllipsisLineLast;
    // Vertical trim removed from the top (ascent above the first line's cap- or
    // x-height) and bottom (descent below the last line's baseline / natural
    // descent). Both are zero when trim is disabled (TextTrimTop/Bottom::none).
    float topTrim;
    float bottomTrim;
};

enum class LineIter : uint8_t
{
    drawLine,
    skipThisLine,
    yOutOfBounds
};

class Text;

#ifdef WITH_RIVE_TEXT
class TextValueRunListener;

class TextValueRunProperty : public PropertySymbolDependentSingle
{
public:
    TextValueRunProperty(Core* textValueRun,
                         TextValueRunListener* textValueRunListener,
                         ViewModelInstanceValue* instanceValue,
                         uint16_t propertyKey,
                         SymbolType symbolType);

    void writeValue() override;

private:
    SymbolType m_symbolType = SymbolType::none;
};

class TextValueRunListener : public CoreObjectListener
{
public:
    TextValueRunListener(TextValueRun* textValueRun,
                         rcp<ViewModelInstance> instance,
                         Text* text);

    void markDirty() override;
    Text* text() { return m_text; }
    TextValueRun* textValueRun()
    {
        if (m_core)
        {
            return m_core->as<TextValueRun>();
        }
        return nullptr;
    }

protected:
    void createProperties() override;

private:
    Text* m_text = nullptr;
    void createPropertyListener(SymbolType symbolType);
    TextValueRunProperty* createSinglePropertyListener(SymbolType symbolType);
};
#endif

struct ColorGlyphCacheKey
{
    const Font* font;
    GlyphID glyphId;
    bool operator==(const ColorGlyphCacheKey& o) const
    {
        return font == o.font && glyphId == o.glyphId;
    }
};

struct ColorGlyphCacheHash
{
    size_t operator()(const ColorGlyphCacheKey& k) const
    {
        size_t h = std::hash<const void*>()(k.font);
        h ^=
            std::hash<uint16_t>()(k.glyphId) + 0x9e3779b9 + (h << 6) + (h >> 2);
        return h;
    }
};

// Sweep gradients have no Rive shader and fall back to their first stop.
void drawColorGlyphLayer(Renderer* renderer,
                         Factory* factory,
                         Font::ColorGlyphLayer& layer,
                         float opacity);

class Text : public TextBase,
             public TextInterface,
             public DataBindListItemConsumer
{
public:
    // Implements TextInterface
    ~Text();
    void markShapeDirty() override;
    void markPaintDirty() override;

    void draw(Renderer* renderer) override;
    Core* hitTest(HitInfo*, const Mat2D&) override;
    void addRun(TextValueRun* run);
    void addModifierGroup(TextModifierGroup* group);
#ifdef WITH_RIVE_EDITOR
    void addModifierGroupForEditor(TextModifierGroup* group);
    void removeModifierGroupForEditor(TextModifierGroup* group);
    /// Re-order `m_allRuns` (and `m_runs`) by the caller-supplied
    /// comparator. The runtime `.riv` import preserves sibling
    /// order via the exporter; coop hydration delivers cores in
    /// arrival order, so the editor needs to re-sort after batch
    /// finalize so concatenated text reads in FractionalIndex
    /// order ("100%", not "%100").
    void sortRunsForEditor(
        const std::function<bool(TextValueRun*, TextValueRun*)>& cmp);
#endif
    void markShapeDirty(bool sendToLayout);
    void modifierShapeDirty();

    void update(ComponentDirt value) override;
    void onDirty(ComponentDirt value) override;

    // Participates in a parent layout via an optional
    // LayoutParticipant child (origin-based; text sizes via its own layout).
    void composeWorldTransform() override;

protected:
    void updateConstraints() override;

public:
    Vec2D layoutBaseTranslation(LayoutParticipant* participant) const;
    LayoutParticipant* layoutParticipant() const;
    bool isParticipatingInLayout() const;

    Mat2D m_transform;
    Mat2D m_shapeWorldTransform;

    const Mat2D& shapeWorldTransform() const { return m_shapeWorldTransform; }
    TextSizing sizing() const { return (TextSizing)sizingValue(); }
    TextSizing effectiveSizing() const;
    TextOverflow overflow() const { return (TextOverflow)overflowValue(); }
    TextOrigin textOrigin() const { return (TextOrigin)originValue(); }
    TextTrimTop verticalTrimTop() const
    {
        return textTrimTop(verticalTrimValue());
    }
    TextTrimBottom verticalTrimBottom() const
    {
        return textTrimBottom(verticalTrimValue());
    }
    TextWrap wrap() const { return (TextWrap)wrapValue(); }
    TextWordBreak wordBreak() const { return (TextWordBreak)wordBreakValue(); }
    VerticalTextAlign verticalAlign() const
    {
        return (VerticalTextAlign)verticalAlignValue();
    }
    TextAlign align() const;
    void overflow(TextOverflow value) { return overflowValue((uint8_t)value); }
    void buildRenderStyles();
    const TextStylePaint* styleFromShaperId(uint16_t id) const;
    bool modifierRangesNeedShape() const;
    // localBounds() is the LAYOUT box, not the ink. Glyphs escape it through
    // negative side bearings, italic overhang, TextOverflow::visible,
    // TextModifierGroup transforms, and per-TextStyle strokes and feathers. It
    // is the right neighbourhood but not a bound, so it is approximate -- a
    // caller sizing a surface must pad it.
    BoundsFidelity paintedWorldBounds(AABB* out) override;

    AABB localBounds() const override;
    AABB constraintBounds() const override { return localBounds(); }
    void originXChanged() override;
    void originYChanged() override;
    StatusCode import(ImportStack& importStack) override;
    Core* clone() const override;

    Vec2D measureLayout(float width,
                        LayoutMeasureMode widthMode,
                        float height,
                        LayoutMeasureMode heightMode) override;
    void controlSize(Vec2D size,
                     LayoutScaleType widthScaleType,
                     LayoutScaleType heightScaleType,
                     LayoutDirection direction) override;
    float effectiveWidth()
    {
        return std::isnan(m_layoutWidth) ? width() : m_layoutWidth;
    }
    float effectiveHeight()
    {
        return std::isnan(m_layoutHeight) ? height() : m_layoutHeight;
    }
    // Whether a fitFontSize text reports its fitted size to the layout. The
    // authored flag only takes effect for files built against that behavior:
    // older ones were laid out against the unshrunk box and would reflow.
    // See Text::import and File::minorVersion.
    bool fitFontSizeResizesBoxActive() const
    {
        return fitFontSizeResizesBox() &&
               hasFileFeature(FileFeatures::fitFontSizeResizesBox);
    }
    // Whether a layout owns our WIDTH axis, asked of the participant rather
    // than of m_layoutWidth: that is only written by controlSize, which runs
    // after the solve, so during the measure pass it is still NAN. A boxed
    // width means the authored width() is not our width -- the layout's offer
    // is.
    bool layoutOwnsWidth() const;
    // Overflow treats the box as fixed once a layout sizes our box.
    bool overflowAsFixed() const
    {
        return effectiveSizing() == TextSizing::fixed ||
               !std::isnan(layoutBoxWidth());
    }
    // The size a controlling layout imposes on our *box*, or NAN when it
    // imposes none. Not the same as effectiveWidth/Height above, which use
    // m_layoutWidth/Height whenever a layout controls us: before 7.3 the
    // layout sized the text but an auto-sized box still came from the
    // content, so these are NAN there. See Text::import.
    float layoutBoxWidth() const
    {
        return hasFileFeature(FileFeatures::layoutSizesBox) ? m_layoutWidth
                                                            : NAN;
    }
    float layoutBoxHeight() const
    {
        return hasFileFeature(FileFeatures::layoutSizesBox) ? m_layoutHeight
                                                            : NAN;
    }
    float computedWidth() override { return localBounds().width(); };
    float computedHeight() override { return localBounds().height(); };
    void updateList(std::vector<rcp<ViewModelInstanceListItem>>* list) override;
#ifdef WITH_RIVE_TEXT
    const std::vector<TextValueRun*>& runs() const { return m_allRuns; }
    /// Breaks paragraphs into lines and aligns them. Lines are aligned within
    /// the larger of the natural paragraph width and minAlignWidth, so a
    /// caller that wants text aligned within a field wider than the text
    /// (see RawTextInput::alignWidth) gets that, while text overflowing the
    /// field falls back to starting at 0.
    static SimpleArray<SimpleArray<GlyphLine>> BreakLines(
        const SimpleArray<Paragraph>& paragraphs,
        float width,
        TextAlign align,
        TextWrap wrap,
        TextWordBreak wordBreak = TextWordBreak::breakWord,
        float minAlignWidth = 0.0f);
    const std::vector<TextStylePaint*>& textStylePaints()
    {
        return m_textStylePaints;
    }
#endif

    bool haveModifiers() const
    {
#ifdef WITH_RIVE_TEXT
        return !m_modifierGroups.empty();
#else
        return false;
#endif
    }
#ifdef TESTING
    const std::vector<OrderedLine>& orderedLines() const
    {
        return m_orderedLines;
    }
    const std::vector<TextModifierGroup*>& modifierGroups() const
    {
        return m_modifierGroups;
    }
    const SimpleArray<Paragraph>& shape() const { return m_shape; }
    const std::vector<Unichar>& unichars() const
    {
        return m_styledText.unichars();
    }
#endif

protected:
    void alignValueChanged() override;
    void sizingValueChanged() override;
    void overflowValueChanged() override;
    void wordBreakValueChanged() override;
    void widthChanged() override;
    void heightChanged() override;
    void paragraphSpacingChanged() override;
    bool makeStyled(StyledText& styledText,
                    bool withModifiers = true,
                    float fontScale = 1.0f) const;
    void originValueChanged() override;
    void verticalTrimValueChanged() override;
    void fitFontSizeResizesBoxChanged() override;

private:
#ifdef WITH_RIVE_TEXT
    friend class TextSelectionController;
    TextSelectionController* m_selectionController = nullptr;
    void updateOriginWorldTransform();
    std::vector<TextValueRun*> m_runs;
    std::vector<TextValueRun*> m_allRuns;
    std::vector<TextStylePaint*> m_renderStyles;
    std::vector<TextDrawCommand> m_drawCommands;
    SimpleArray<Paragraph> m_shape;
    SimpleArray<Paragraph> m_modifierShape;
    SimpleArray<SimpleArray<GlyphLine>> m_lines;
    SimpleArray<SimpleArray<GlyphLine>> m_modifierLines;
    // Runs ordered by paragraph line.
    std::vector<OrderedLine> m_orderedLines;
    GlyphRun m_ellipsisRun;
    RawPath m_clipRect;
    ShapePaintPath m_clipPath;
    AABB m_bounds;
    // The font-size multiplier chosen by the last fitFontSize layout. Per-run
    // values are baked into the shaped runs by makeStyled; paragraph spacing is
    // a Text-level gap added between paragraphs during layout, so it is scaled
    // by this to keep the fitted layout a true uniform scale of the authored
    // one. Only meaningful while fitFontSize is the active overflow -- read it
    // through fitParagraphSpacing(), never directly, so a stale value from a
    // previous fit can't leak into a paint-only rebuild.
    float m_fitFontScale = 1.0f;
    std::vector<TextModifierGroup*> m_modifierGroups;

    StyledText m_styledText;
    StyledText m_modifierStyledText;
    GlyphLookup m_glyphLookup;
    std::vector<TextStylePaint*> m_textStylePaints;

    void clearRenderStyles();
    void drawColorGlyph(Renderer* renderer,
                        const TextDrawCommand::ColorGlyphInfo& info,
                        const Mat2D& worldTransform);
    std::
        unordered_map<ColorGlyphCacheKey, rcp<RenderImage>, ColorGlyphCacheHash>
            m_emojiImageCache;
    float fitParagraphSpacing() const
    {
        return overflow() == TextOverflow::fitFontSize
                   ? paragraphSpacing() * m_fitFontScale
                   : paragraphSpacing();
    }
    TextBoundsInfo computeBoundsInfo();
    // For TextOverflow::fitFontSize: binary-searches the largest integer font
    // size that fits the bounds and returns it as a multiplier of the authored
    // font size(s). Returns 1.0f when no fitting is needed/possible.
    float fitFontScale();
    // Same search, against an explicit box. Used by measure(), where the box
    // Yoga is offering is not yet reflected in m_layoutWidth/Height.
    float fitFontScale(float boxWidth, float boxHeight);
    LineIter shouldDrawLine(float y, float totalHeight, const GlyphLine& line);
    void buildTextStylePaints();
    std::vector<TextValueRunListener*> m_valueRunListeners;

#endif
    float m_layoutWidth = NAN;
    float m_layoutHeight = NAN;
    uint8_t m_layoutWidthScaleType = std::numeric_limits<uint8_t>::max();
    uint8_t m_layoutHeightScaleType = std::numeric_limits<uint8_t>::max();
    LayoutDirection m_layoutDirection = LayoutDirection::inherit;
    // Behaviors the file's version opts into, stamped in Text::import from
    // the header. Each one guards a change that would relayout content
    // authored before it, so a file predating the change keeps the old
    // behavior; anything built in memory is current and gets them all.
    //
    // One mask rather than a bool apiece because they are all the same shape
    // -- stamp at import, carry through clone, read at a single call site --
    // so the next gate costs a bit instead of a member plus its plumbing.
    // See File::minorVersion for what each version changed.
    enum class FileFeatures : uint8_t
    {
        none = 0,
        // 7.3: a controlling layout sizes our box, not just our text. Below
        // this an auto-sized text still took its box from the content, so the
        // box could disagree with the slot and every overflow mode was inert.
        layoutSizesBox = 1 << 0,
        // 7.4: Text::fitFontSizeResizesBox is honored, so a fitFontSize text
        // reports its *fitted* size to the layout instead of reserving room
        // at the authored font size.
        fitFontSizeResizesBox = 1 << 1,
        all = layoutSizesBox | fitFontSizeResizesBox,
    };
    FileFeatures m_fileFeatures = FileFeatures::all;
    bool hasFileFeature(FileFeatures feature) const
    {
        return enums::is_flag_set(m_fileFeatures, feature);
    }
    Vec2D measure(Vec2D maxSize);
};
} // namespace rive

#endif