CodeEditor.h

Go to the documentation of this file.

// Copyright (c) 2025 Dave R. Smith.
// Malena Framework — Licensed under PolyForm Noncommercial 1.0.0; commercial use requires a paid license. See LICENSE.
 
#ifndef MALENA_CODEEDITOR_H
#define MALENA_CODEEDITOR_H
 
#pragma once
 
#include <Malena/Core/malena_export.h>
#include <Malena/Graphics/Text/TextArea.h>
#include <SFML/Graphics/Color.hpp>
#include <cstddef>
#include <memory>
#include <string>
#include <unordered_set>
#include <vector>
 
namespace ml
{
    // ── Languages ───────────────────────────────────────────────────────────────
    enum class CodeLanguage { Plain, Cpp, Python, JavaScript, Java };
 
    // ── SyntaxToken ───────────────────────────────────────────────────────────────
    struct SyntaxToken
    {
        std::size_t start = 0;
        std::size_t end   = 0;
        sf::Color   color;
    };
 
    // ── SyntaxHighlighter ─────────────────────────────────────────────────────────
    class MALENA_API SyntaxHighlighter
    {
    public:
        virtual ~SyntaxHighlighter() = default;
        [[nodiscard]] virtual std::vector<SyntaxToken> tokenize(const std::string& text) const = 0;
    };
 
    // ── BasicSyntaxHighlighter ──────────────────────────────────────────────────
    class MALENA_API BasicSyntaxHighlighter : public SyntaxHighlighter
    {
    public:
        explicit BasicSyntaxHighlighter(CodeLanguage lang = CodeLanguage::Cpp);
 
        void setLanguage(CodeLanguage lang);
        [[nodiscard]] CodeLanguage language() const { return _lang; }
 
        [[nodiscard]] std::vector<SyntaxToken> tokenize(const std::string& text) const override;
 
        // Theme colors (override freely).
        sf::Color keywordColor { 197, 134, 192 };   // purple
        sf::Color stringColor  { 206, 145, 120 };   // orange
        sf::Color commentColor { 106, 153,  85 };   // green
        sf::Color numberColor  { 181, 206, 168 };   // light green
 
    private:
        CodeLanguage                     _lang;
        std::unordered_set<std::string>  _keywords;
        bool                             _hashComments = false; // '#' line comments
    };
 
    // ── CodeEditor ──────────────────────────────────────────────────────────────
    class MALENA_API CodeEditor : public TextArea
    {
    public:
        static const sf::Font& monospaceFont();
 
        explicit CodeEditor(const sf::Font& font = monospaceFont());

        void setLanguage(CodeLanguage lang);

        void setHighlighter(std::shared_ptr<SyntaxHighlighter> highlighter);
 
    protected:
        void onRebuildComplete() override;
 
    private:
        void applyHighlighting();
 
        std::shared_ptr<SyntaxHighlighter> _highlighter;
        BasicSyntaxHighlighter*            _basic = nullptr; // non-owning alias when built-in
        std::string                        _lastHighlighted;
        bool                               _inHighlight = false;
    };
 
} // namespace ml
 
#endif // MALENA_CODEEDITOR_H