// Location.h

#ifndef dset__Location_H
#define dset__Location_H

// David Adams
// July 2003
//
// Class to describe the location of a dataset. For now this is
// just a collection of file URL's. In the future the contents
// of this class might be extended or it might be abstracted to
// support extensions.
//
// XML representation:
//
// Location
//   Url
//     url=guid:123
//   Url
//     url=guid:456
//   ...

#include <vector>
#include <iosfwd>
#include "dataset_util/Text.h"
#include "dataset_util/XmlElement.h"
#include "dataset_file/Url.h"

class XmlElement;

namespace dset {

class Location {

public:  // typedefs

  typedef std::vector<Url> UrlList;

private:  // data

  // Error status.
  int m_error;

  // List of URL's
  UrlList m_files;

public:  // static functions

  // XML name.
  static const char* xml_name() { return "Location"; }

  // DTD.
  static const Text& dtd();

public:  // const functions

  // Constructor for empty or invalid location.
  // Invalid if error is nonzero.
  explicit Location(int error =0);

  // Constructor from XML.
  explicit Location(const XmlElement& ele);

  // Validity.
  // Valid if error status is zero.
  bool is_valid() const;

  // Error status.
  int error() const;

  // Is the location empty?
  // I.e. is valid and holds no files.
  bool is_empty() const;

  // Return the const list of files.
  const UrlList& files() const;

  // Return the mutable list of files.
  UrlList& files();

  // Size of managed memory in bytes.
  size_t memsize() const;

  // XML representation.
  const XmlElement* xml() const;

  // Output stream.
  std::ostream& ostr(std::ostream& lhs, std::string indent,
                     std::string label="Location") const;

public:  // non-const functions

  // Add another location.
  // Result is a combined list of files without duplicates.
  // Returns 0 for success.
  int add(const Location& loc);

};

// Equality.
// Must have the same files in the same order.
bool operator==(const Location& lhs, const Location& rhs);

// Inequality.
bool operator!=(const Location& lhs, const Location& rhs);

};  // end namespace dset

// Output stream.
std::ostream& operator<<(std::ostream& lhs, dset::Location rhs);

#endif