#pragma once

#include <vector>
#include <memory>
#include <string>
#include <pdfengine/graphics_state.hpp>
#include <pdfengine/path.hpp>
#include <pdfengine/image.hpp>
namespace pdfengine {

class CommandVisitor;

struct Command {
    virtual ~Command() = default;
    virtual void accept(CommandVisitor& visitor) const = 0;
};


struct SaveStateCommand : public Command {
    void accept(CommandVisitor& visitor) const override;
};

struct RestoreStateCommand : public Command {
    void accept(CommandVisitor& visitor) const override;
};

struct SetTransformCommand : public Command {
    Matrix matrix;
    explicit SetTransformCommand(const Matrix& m) : matrix(m) {}
    void accept(CommandVisitor& visitor) const override;
};

struct FillRectCommand : public Command {
    float x, y, width, height;
    FillRectCommand(float x, float y, float w, float h) : x(x), y(y), width(w), height(h) {}
    void accept(CommandVisitor& visitor) const override;
};

struct DrawTextCommand : public Command {
    std::string text;
    float x, y;
    DrawTextCommand(std::string text, float x, float y) : text(std::move(text)), x(x), y(y) {}
    void accept(CommandVisitor& visitor) const override;
};

struct FillPathCommand : public Command {
    Path path;
    explicit FillPathCommand(Path path) : path(std::move(path)) {}
    void accept(CommandVisitor& visitor) const override;
};

struct StrokePathCommand : public Command {
    Path path;
    explicit StrokePathCommand(Path path) : path(std::move(path)) {}
    void accept(CommandVisitor& visitor) const override;
};

struct DrawImageCommand : public Command {
    ImageInfo image;
    Matrix matrix;
    float opacity;

    DrawImageCommand(ImageInfo img, Matrix m, float op = 1.0f) 
        : image(std::move(img)), matrix(m), opacity(op) {}
    void accept(CommandVisitor& visitor) const override;
};



class CommandVisitor {
public:
    virtual ~CommandVisitor() = default;
    virtual void visit(const SaveStateCommand& cmd) = 0;
    virtual void visit(const RestoreStateCommand& cmd) = 0;
    virtual void visit(const SetTransformCommand& cmd) = 0;
    virtual void visit(const FillRectCommand& cmd) = 0;
    virtual void visit(const DrawTextCommand& cmd) = 0;
    virtual void visit(const FillPathCommand& cmd) = 0;
    virtual void visit(const StrokePathCommand& cmd) = 0;
    virtual void visit(const DrawImageCommand& cmd) = 0;
};


class DisplayList {
public:
    DisplayList() = default;
    
    void addCommand(std::unique_ptr<Command> cmd);

    void replay(CommandVisitor& visitor) const;

    void saveState();
    void restoreState();
    void setTransform(const Matrix& m);
    void fillRect(float x, float y, float w, float h);
    void drawText(const std::string& text, float x, float y);
    void fillPath(const Path& path);
    void strokePath(const Path& path);
    void drawImage(const ImageInfo& image, const Matrix& m, float opacity = 1.0f);

    [[nodiscard]] size_t size() const noexcept { return m_commands.size(); }
    void clear() { m_commands.clear(); }

private:
    std::vector<std::unique_ptr<Command>> m_commands;
};

}