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/// \file engine/context.hpp
/// Representation of runtime contexts.

#if !defined(ENGINE_CONTEXT_HPP)
#define ENGINE_CONTEXT_HPP

#include <map>
#include <ostream>
#include <string>

#include "utils/fs/path.hpp"
#include "utils/shared_ptr.hpp"

namespace engine {


/// Representation of a runtime context.
///
/// The instances of this class are unique (i.e. copying the objects only yields
/// a shallow copy that shares the same internal implementation).  This is a
/// requirement for the 'store' API model.
class context {
    struct impl;

    /// Pointer to the shared internal implementation.
    std::shared_ptr< impl > _pimpl;

public:
    context(const utils::fs::path&,
            const std::map< std::string, std::string >&);
    ~context(void);
    static context current(void);

    const utils::fs::path& cwd(void) const;
    const std::map< std::string, std::string >& env(void) const;

    bool operator==(const context&) const;
    bool operator!=(const context&) const;
};


std::ostream& operator<<(std::ostream&, const context&);


}  // namespace engine

#endif  // !defined(ENGINE_CONTEXT_HPP)