#ifndef jk_VM_HPP
#define jk_VM_HPP

#include "commons.hpp"
#include "Program.hpp"

namespace jk
{
  struct Frame {
    std::shared_ptr<Program> program;
    std::unordered_map<int, std::shared_ptr<Value>> locals;
    size_t ret_addr;
    size_t stack_sz;
  };

  class VM
  {
  public:
    explicit VM();
    virtual ~VM();

    void execute(std::shared_ptr<Program> program);
    void execute();

    std::string string() const;

    size_t push_heap(std::shared_ptr<Value> value);
    std::shared_ptr<Value> heap(size_t addr);

    void set_global(size_t addr, std::shared_ptr<Value> value);

  private:
    size_t m_pc = 0;
    std::vector<Frame> m_frames;
    std::vector<param_t> m_stack;
    std::vector<std::shared_ptr<Value>> m_heap;
    std::unordered_map<size_t, std::shared_ptr<Value>> m_globals;

    void push(param_t param);
    param_t pop();

    std::shared_ptr<Program> program() const;
  };
}

#endif