// EventIdRange.h

#ifndef EventIdRange_H
#define EventIdRange_H

// David Adams
// June 2002
//
// Range of event ID's with the same run number and a contiguous
// set of event numbers.
//
// XML format:
//
// EventIdRange
//   run = 123
//   first = 24001
//   last  = 24199
//

#include "dataset_id/EventId.h"
#include <iosfwd>

class XmlElement;

class EventIdRange {

public:  // Typedefs

  typedef unsigned long size_type;

public:  // static functions

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

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

private:  // data

  EventId _id;
  size_type _size;

public:

  // Default constructor.
  EventIdRange();

  // Full constructor from event ID.
  explicit EventIdRange(EventId id, size_type size =1);

  // Full constructor from run and event numbers.
  EventIdRange(EventId::RunNumber run, EventId::EventNumber evt1,
               EventId::EventNumber evt2);

  // XML constructor.
  explicit EventIdRange(const XmlElement& ele);

public:  // const functions

  // Return the run number.
  EventId::RunNumber run() const { return _id.run(); }

  // Return the first event number.
  EventId::EventNumber first_event() const
    { return _id.event(); }

  // Return the last event number.
  EventId::EventNumber last_event() const
    { return _id.event() + _size - 1; }

  // Return the number of event ID's.
  size_type size() const { return _size; }

  // Return if this is a valid range.
  bool is_valid() const { return _size>0 && _id.is_valid(); }

  // Contains another range?
  bool contains(const EventIdRange& rng) const;

  // Write to XML.
  const XmlElement* xml() const;

public:  // mutating functions

  // Remove the first event.
  void pop_front();

  // Remove the last event.
  void pop_back();

};

// Ordering operator.
// Ranges may not overlap or be adjacent.
bool operator<(const EventIdRange& lhs, const EventIdRange& rhs);

// Equality.
// Ranges must be identical.
bool operator==(const EventIdRange& lhs, const EventIdRange& rhs);

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

// Output stream.
std::ostream& operator<<(std::ostream& lhs, const EventIdRange& rhs);
#endif