json-validator/include/jvalidate/uri.h

#pragma once

#include <string>
#include <string_view>

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

namespace jvalidate {
class URI {
private:
  std::string uri_;
  size_t scheme_{0};
  size_t resource_{0};

public:
  URI() = default;

  explicit URI(std::string_view uri) : uri_(uri) {
    if (not uri_.empty() && uri_.back() == '#') {
      uri_.pop_back();
    }

    if (size_t n = uri_.find("://"); n != std::string::npos) {
      scheme_ = n;
      resource_ = n + 3;
    } else if (uri_.starts_with("urn:")) {
      n = uri_.find(':', 4);
      scheme_ = n;
      resource_ = scheme_ + 1;
    }
  }

  URI parent() const { return URI(std::string_view(uri_).substr(0, uri_.rfind('/'))); }
  URI root() const { return URI(std::string_view(uri_).substr(0, uri_.find('/', resource_))); }

  URI operator/(URI const & relative) const {
    std::string div = uri_.ends_with("/") || relative.uri_.starts_with("/") ? "" : "/";
    return URI(uri_ + div + relative.uri_);
  }

  bool is_rootless() const { return scheme_ == 0; }
  bool is_relative() const { return uri_[resource_] != '/'; }
  std::string_view scheme() const { return std::string_view(uri_).substr(0, scheme_); }
  std::string_view resource() const { return std::string_view(uri_).substr(resource_); }

  explicit operator std::string const &() const { return uri_; }
  char const * c_str() const { return uri_.c_str(); }
  bool empty() const { return uri_.empty(); }

  friend std::ostream & operator<<(std::ostream & os, URI const & self) { return os << self.uri_; }

  auto operator<=>(URI const & lhs) const = default;
};
}