#pragma once

#include <string>
#include <string_view>

#include <jvalidate/detail/expect.h>
#include <jvalidate/detail/pointer.h>

namespace jvalidate::detail {
class Reference {
public:
  Reference() = default;
  Reference(std::string const & anchor, Pointer const & pointer)
      : anchor_(anchor), pointer_(pointer) {}
  Reference(std::string_view fragment, bool allow_anchor = true) {
    EXPECT_M(fragment.find('#') != std::string::npos, "Reference requires a fragment token '#'");

    size_t const index = fragment.find('/');

    anchor_ = std::string(fragment.substr(0, index));
    EXPECT_M(allow_anchor && anchor_.back() == '#', "Anchoring is not allowed in this context");

    if (index != std::string::npos) {
      pointer_ = fragment.substr(index + 1);
    }
  }

  std::string const & anchor() const { return anchor_; }
  Pointer const & pointer() const { return pointer_; }
  Reference parent() const { return {anchor_, pointer_.parent()}; }

  Reference & operator/=(Pointer const & relative) {
    pointer_ /= relative;
    return *this;
  }

  Reference operator/(Pointer const & relative) const { return Reference(*this) /= relative; }

  Reference & operator/=(std::string_view key) {
    pointer_ /= key;
    return *this;
  }

  Reference operator/(std::string_view key) const { return Reference(*this) /= key; }

  Reference & operator/=(size_t index) {
    pointer_ /= index;
    return *this;
  }

  Reference operator/(size_t index) const { return Reference(*this) /= index; }

  friend std::ostream & operator<<(std::ostream & os, Reference const & self) {
    return os << self.anchor_ << self.pointer_;
  }
  auto operator<=>(Reference const &) const = default;

private:
  std::string anchor_;
  Pointer pointer_;
};
}