// file      : build/target-key -*- C++ -*-
// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
// license   : MIT; see accompanying LICENSE file

#ifndef BUILD_TARGET_KEY
#define BUILD_TARGET_KEY

#include <map>
#include <string>
#include <ostream>
#include <functional>  // reference_wrapper

#include <butl/utility> // compare_c_string

#include <build/types>
#include <build/target-type>

namespace build
{
  // Light-weight (by being shallow-pointing) target key.
  //
  class target_key
  {
  public:
    mutable const target_type* type;
    mutable const dir_path* dir;
    mutable const std::string* name;
    mutable const std::string* const* ext; // Note: only *ext can be NULL.

    friend bool
    operator< (const target_key& x, const target_key& y)
    {
      const target_type* xt (x.type);
      const target_type* yt (y.type);

      //@@ TODO: use compare() to compare once.

      // Unspecified and specified extension are assumed equal. The
      // extension strings are from the pool, so we can just compare
      // pointers.
      //
      return
        (xt < yt) ||
        (xt == yt && *x.name < *y.name) ||
        (xt == yt && *x.name == *y.name && *x.dir < *y.dir) ||
        (xt == yt && *x.name == *y.name && *x.dir == *y.dir &&
         *x.ext != nullptr && *y.ext != nullptr && **x.ext < **y.ext);
    }
  };

  std::ostream&
  operator<< (std::ostream&, const target_key&); // Defined in target.cxx
}

#endif // BUILD_TARGET_KEY