// Phil Ottewell's STL Course - http://www.pottsoft.com/home/stl/stl.htmlx
//
// Example 4.3                  © Phil Ottewell 1997 <philXZY@pottsoftXZY_REMOVEXYZ.com>
//
// Purpose:
//          Demonstrate use of priority_queue container adaptor
//          by using a task/priority structure
//

// ANSI C Headers
#include <stdlib.h>

// C++ STL Headers
#include <functional>
#include <iostream>
#include <queue>
#include <string>
#include <vector>

#ifdef _WIN32
using namespace std;
#endif

class TaskObject {
public:
    friend class PrioritizeTasks;
    friend ostream & operator<<( ostream &os, TaskObject &task);
    TaskObject( const char *pname = "", unsigned int prio = 4 )
    {
      process_name = pname;
      priority = prio;
    }
private:
    unsigned int priority;
    string process_name;
};

// Friend function for "printing" TaskObject to an output stream
ostream & operator<<( ostream &os, TaskObject &task )
{
    os << "Process: " << task.process_name << " Priority: " << task.priority;
    return ( os );
}

// Friend class with function object for comparison of TaskObjects
class PrioritizeTasks {
public :
    int operator()( const TaskObject &x, const TaskObject &y )
    {
      return x.priority < y.priority;
    }
};

int main( int argc, char *argv[] )
{
    int i;
    priority_queue<TaskObject, vector<TaskObject>, PrioritizeTasks> task_queue;

    TaskObject tasks[] = { "JAF", "ROB", "PHIL", "JOHN"
                          ,TaskObject("OPCOM",6)  , TaskObject("Swapper",16)
                          ,TaskObject("NETACP",8) , TaskObject("REMACP",8) };
                            
    for ( i = 0; i < sizeof(tasks)/sizeof(tasks[0]) ; i++ )
      task_queue.push( tasks[i] );

    while ( !task_queue.empty() ) {
        cout << task_queue.top() << endl; task_queue.pop();
    }
    cout << endl;

    return( EXIT_SUCCESS );
}