class JobStateFlags:
	RUNNING=1	# the job is running
	WAITING=2	# the job is waiting
	QUEUED=4		# not sure what that exactly means but it reflects the q state of jobs as seen in the pending jobs list from qstat -f -u \*
	TRANSFERING=8
	DELETED=16
	HOLD=32
	ERROR=64
	
class ParallelEnvironment:
	MPI=1
	
class JobRequirements:
	def __init__( self ):
		self.m_numSlots = None
		self.m_strArchitecture = None	# machine architecture
		self.m_parallelEnvironment = None
		self.m_queues = None # the list of queues this job is allowed to run on


class JobId:
	"""
		the identifier of a job.
		We treat each element of a job array as a separate job
		A single integer is no longer enough to identify a job because all elements in a job array
		share the same sge job identifier. To uniquely define a job array element, we also use the task id.
	"""
	def __init__( self, iJobId, iJobArrayElementId = None):
		self.m_iJobId = iJobId
		self.m_iJobArrayElementId = iJobArrayElementId # None if this identifier does not refer to a job array element
		
	def __hash__( self ):
		"""
			required to use a JobId as a dict hash key
		"""
		return self.m_iJobId # very simple hashing that conflicts only for job array elements
	
	def __eq__( self, other ):
		"""
			required to use a JobId as a dict hash key
		"""
		if self.m_iJobId != other.m_iJobId:
			return False
		if self.m_iJobArrayElementId != other.m_iJobArrayElementId:
			return False
		return True
		
	def isJobArrayElement( self ):
		return (self.m_iJobArrayElementId != None)
	
	def asStr( self ):
		strResult = '%s' % self.m_iJobId
		if self.isJobArrayElement():
			strResult += '.%d' % self.m_iJobArrayElementId
		return strResult
		


class Job:
	def __init__( self, jobId ):
		self.m_jobId = jobId
		self.m_startTime = None
		self.m_submitTime = None
		self.m_owner = None
		self.m_scriptName = None
		self.m_slots = {}
		self.m_stateFlags = 0
		self.m_jobRequirements = JobRequirements()
		self.m_requestedRamPerCore = 0
	def getId( self ):
		return self.m_jobId
	def setState( self, state ):
		self.m_stateFlags = state
	def setOwner( self, jobOwner ):
		if self.m_owner:
			assert( self.m_owner == jobOwner ) 
		self.m_owner = jobOwner
	def getOwner( self ):
		return self.m_owner
	def setStartTime( self, jobStartTime ):
		if self.m_startTime:
			assert( self.m_startTime == jobStartTime ) 
		self.m_startTime = jobStartTime
	def setSubmitTime( self, jobSubmitTime ):
		if self.m_submitTime:
			assert( self.m_submitTime == jobSubmitTime ) 
		self.m_submitTime = jobSubmitTime
	def getStartTime( self ):
		return self.m_startTime
	def setScriptName( self, jobScriptName ):
		if self.m_scriptName:
			assert( self.m_scriptName == jobScriptName ) 
		self.m_scriptName = jobScriptName
	def addSlots( self, queueMachineName, numSlots ):
		assert( self.m_slots.get( queueMachineName ) == None )
		if self.m_slots.get( queueMachineName ) == None:
			self.m_slots[ queueMachineName ] = numSlots
		else:
			# should never happen
			self.m_slots[ queueMachineName ] += numSlots
	def getSlots( self ):
		return self.m_slots
	def setNumRequiredSlots( self, numSlots ):
		self.m_jobRequirements.m_numSlots = numSlots
	def isPending( self ):
		"""
			returns true if this job is waiting in the queue for whatever reason
		"""
		return self.m_stateFlags & JobStateFlags.QUEUED
	def getRequestedRamPerCore( self ):
		"""
			requested RAM per core in bytes
		"""
		return self.m_requestedRamPerCore
	def setRequestedRamPerCore( self, requestedRam ):
		"""
			requestedRam : requested RAM per core in bytes
		"""
		self.m_requestedRamPerCore=requestedRam