// file      : build/prerequisite -*- C++ -*-
// copyright : Copyright (c) 2014-2015 Code Synthesis Tools CC
// license   : MIT; see accompanying LICENSE file

#ifndef BUILD_PREREQUISITE
#define BUILD_PREREQUISITE

#include <set>
#include <string>
#include <iosfwd>
#include <utility>    // move
#include <typeindex>

#include <build/path>
#include <build/utility> // extension_pool
#include <build/diagnostics>

namespace build
{
  class scope;
  class target;
  class target_type;

  class prerequisite
  {
  public:
    typedef build::target target_type;
    typedef build::target_type target_type_type;
    typedef build::scope scope_type;

    prerequisite (const target_type_type& t,
                  path d,
                  std::string n,
                  const std::string* e,
                  scope_type& s)
        : type (t), dir (std::move (d)), name (std::move (n)), ext (e),
          scope (s), target (0) {}

  public:
    const target_type_type& type;
    const path dir;         // Normalized absolute or relative (to scope).
    const std::string name;
    const std::string* ext; // NULL if unspecified.
    scope_type& scope;
    target_type* target;    // NULL if not yet resolved.
  };

  std::ostream&
  operator<< (std::ostream&, const prerequisite&);

  bool
  operator< (const prerequisite&, const prerequisite&);

  struct prerequisite_set: std::set<prerequisite>
  {
    std::pair<prerequisite&, bool>
    insert (const target_type&,
            path dir,
            std::string name,
            const std::string* ext,
            scope&,
            tracer&);
  };
}

#endif // BUILD_PREREQUISITE