#include <string>
#include <boost/test/auto_unit_test.hpp>
#include "../RwMutex.h"
#include "../MutexException.h"

BOOST_AUTO_TEST_SUITE( RwMutex );

using namespace CCDom;

//! Gets a timeout 1s in the future
boost::xtime getTimeout()
{
  boost::xtime timeout;
  BOOST_CHECK( 0 != boost::xtime_get(&timeout, boost::TIME_UTC) );
  timeout.sec += 1;
  return timeout;
}

BOOST_AUTO_TEST_CASE( test_single_lock )
{
  // Create a read-write mutex and obtain a read-lock
  RwMutex mutex;
  RwMutex::Lock lock(mutex, getTimeout());
  
  // Should be able to promote to a write lock if only one reader
  {
    RwMutex::WriteLock writeLock(lock, getTimeout());
  }
  
  // Obtain a second lock and should no longer be able to obtain a write
  // lock on either read locks
  {
    RwMutex::Lock lock2(mutex, getTimeout());
    BOOST_CHECK_THROW(RwMutex::WriteLock(lock, getTimeout()), MutexException);
    BOOST_CHECK_THROW(RwMutex::WriteLock(lock2, getTimeout()), MutexException);
  }
  
  // Once the second lock bas been released, should again be able to obtain a write lock
  {
    RwMutex::WriteLock writeLock(lock, getTimeout());
    
    // After obtaining the write lock, shouldn't be able to obtain another read lock
    BOOST_CHECK_THROW(RwMutex::Lock(mutex, getTimeout()), MutexException);
  }
  
}

BOOST_AUTO_TEST_SUITE_END();