#ifndef option_hh_INCLUDED
#define option_hh_INCLUDED

#include "exception.hh"
#include "meta.hh"
#include "string.hh"
#include "vector.hh"

namespace Kakoune
{

class String;
enum class Quoting;

// Forward declare functions that wont get found by ADL
inline String option_to_string(int opt);
inline String option_to_string(size_t opt);
inline String option_to_string(bool opt);

// Default fallback to single value functions
template<typename T>
decltype(option_from_string(Meta::Type<T>{}, StringView{}))
option_from_strings(Meta::Type<T>, ConstArrayView<String> strs)
{
    if (strs.size() != 1)
        throw runtime_error("expected a single value for option");
    return option_from_string(Meta::Type<T>{}, strs[0]);
}

template<typename T>
Vector<decltype(option_to_string(std::declval<T>(), Quoting{}))>
option_to_strings(const T& opt)
{
    return Vector<String>{option_to_string(opt, Quoting{})};
}

template<typename T>
decltype(option_add(std::declval<T>(), std::declval<String>()))
option_add_from_strings(T& opt, ConstArrayView<String> strs)
{
    if (strs.size() != 1)
        throw runtime_error("expected a single value for option");
    return option_add(opt, strs[0]);
}

template<typename T>
decltype(option_add(std::declval<T>(), std::declval<String>()))
option_remove_from_strings(T& opt, ConstArrayView<String> strs)
{
    if (strs.size() != 1)
        throw runtime_error("expected a single value for option");
    return option_remove(opt, strs[0]);
}

template<typename P, typename T>
struct PrefixedList
{
    P prefix;
    Vector<T, MemoryDomain::Options> list;

    friend bool operator==(const PrefixedList& lhs, const PrefixedList& rhs) = default;
};

template<typename T>
using TimestampedList = PrefixedList<size_t, T>;


class Option;

class OptionWatcher
{
public:
    virtual void on_option_changed(const Option& option) = 0;
};

}

#endif // option_hh_INCLUDED
