# -*- encoding=utf-8 -*-
# In order for mpy module to work, don't forget to make a symlink to yade executable named "yadeimport.py":
# ln -s path/to/yade/yade-version path/to/yade/yadeimport.py
#
# Possible executions of this script
### Parallel:
# mpiexec -n 4 yade-mpi -n -x testMPIxNxM.py
# mpiexec -n 4 yade-mpi  -n -x testMPIxN.py N M # (n-1) subdomains with NxM spheres each
### Monolithic:
# yade-mpi -n -x testMPIxN.py
# yade-mpi -n -x testMPIxN.py N M
# yade-mpi -n -x testMPIxN.py N M n
# in last line the optional argument 'n' has the same meaning as with mpiexec, i.e. total number of bodies will be (n-1)*N*M but on single core
### Openmp:
# yade-mpi -j4 -n -x testMPIxN.py N M n
### Nexted MPI * OpenMP
# needs testing...
'''
This script simulates spheres falling on a plate using a distributed memory approach based on mpy module
The number of spheres assigned to one particular process (aka 'worker') is N*M, they form a regular patern.
The master process (rank=0) has no spheres assigned; it is in charge of getting the total force on the plate
The number of subdomains depends on argument 'n' of mpiexec. Since rank=0 is not assigned a regular subdomain the total number of spheres is (n-1)*N*M

'''
readParamsFromTable(noTableOk=True, N=100, M=10)
from yade.params.table import *

NSTEPS = 2000  #turn it >0 to see time iterations, else only initilization
#N=100; M=100; #(columns, rows) per thread

#################
# Check MPI world
# This is to know if it was run with or without mpiexec (see preamble of this script)
import os
import time
import re

# Stop script before walltime ends
m_hasWalltime = 'YADE_WALLTIME' in os.environ
m_Walltime = 0
m_WalltimeStopAt = 0.95

if m_hasWalltime:
	walltime = os.environ['YADE_WALLTIME']
	if re.search("^([0-9]+):([0-9]{2}):([0-9]{2})$", walltime):
		w = re.match("^([0-9]+):([0-9]{2}):([0-9]{2})$", walltime)
		g = w.groups()
		m_Walltime = 3600 * float(g[0]) + 60 * float(g[1]) + float(g[2])
		print "Will run for %i seconds" % m_Walltime
	else:
		print "Wrong walltime format."
		m_hasWalltime = False


def SaveAndQuit():
	print "Quit due to walltime expiration"
	O.stopAtIter = O.iter + 1


#time.sleep(5)
O.engines += [PyRunner(command='time.sleep(.005)', iterPeriod=1)]

if m_hasWalltime:
	O.engines += [PyRunner(command='SaveAndQuit()', realPeriod=m_Walltime * m_WalltimeStopAt)]

timeStr = time.strftime('%m-%d-%Y')
rank = os.getenv('OMPI_COMM_WORLD_RANK')
if rank is not None:  #mpiexec was used
	rank = int(rank)
	numThreads = int(os.getenv('OMPI_COMM_WORLD_SIZE'))
# else: #non-mpi execution, numThreads will still be used as multiplier for the problem size (2 => multiplier is 1)
# 	numThreads=2 if len(sys.argv)<4 else (int(sys.argv[3]))
# 	print "numThreads",numThreads
#
# if len(sys.argv)>1: #we then assume N,M are provided as 1st and 2nd cmd line arguments
# 	N=int(sys.argv[1]); M=int(sys.argv[2])

############  Build a scene (we use Yade's pre-filled scene)  ############

# sequential grain colors
import colorsys
colorScale = (Vector3(colorsys.hsv_to_rgb(value * 1.0 / numThreads, 1, 1)) for value in range(0, numThreads))

#add spheres
if rank == 0:
	for sd in range(0, numThreads - 1):
		col = next(colorScale)
		ids = []
		for i in range(N):  #(numThreads-1) x N x M spheres, one thread is for master and will keep only the wall, others handle spheres
			for j in range(M):
				id = O.bodies.append(
				        sphere((sd * N + i + j / 30., j, 0), 0.500, color=col)
				)  #a small shift in x-positions of the rows to break symmetry
				ids.append(id)
		if rank is not None:  # assigning subdomain!=0 in single thread would freeze the particles (Newton skips them)
			for id in ids:
				O.bodies[id].subdomain = sd + 1

WALL_ID = O.bodies.append(box(center=(numThreads * N * 0.5, -0.5, 0), extents=(2 * numThreads * N, 0, 2), fixed=True))

collider.verletDist = 0.7
collider.targetInterv = 200
newton.gravity = (0, -10, 0)  #else nothing would move
tsIdx = O.engines.index(timeStepper)  #remove the automatic timestepper. Very important: we don't want subdomains to use many different timesteps...
O.engines = O.engines[0:tsIdx] + O.engines[tsIdx + 1:]
#O.dt=0.00002 #this very small timestep will make it possible to run 2000 iter without merging
O.dt = 0.1 * PWaveTimeStep()  #very important, we don't want subdomains to use many different timesteps...


def collectTimingMPI():
	created = os.path.isfile("collect_2D_weakScalability-" + timeStr + ".dat")
	f = open("collect_2D_weakScalability-" + timeStr + ".dat", 'a')
	if not created:
		f.write("numThreads mpi omp Nspheres force TotalRuntime isendRecvForces sendRecvStates waitForces collisionChecker collider\n")
	from yade import timing
	#f.write(str(globalDomain.numThreads)+" "+str(os.getenv('OMPI_COMM_WORLD_SIZE'))+" "+os.getenv('OMP_NUM_THREADS')+" "+str(len(O.bodies))++" "+str(O.forces.f(WALL_ID)[1])+" "+str(timing.runtime())+" ""\n")
	f.write(
	        "%s %s %s %g %g %g %g %g %g %g %g\n" % (
	                numThreads, str(os.getenv('OMPI_COMM_WORLD_SIZE')), os.getenv('OMP_NUM_THREADS'), len(O.bodies), O.forces.f(WALL_ID)[1],
	                timing.runtime() / 1e6, isendRecvForcesRunner.execTime / 1e6, sendRecvStatesRunner.execTime / 1e6, waitForcesRunner.execTime / 1e6,
	                collisionChecker.execTime / 1e6, collider.execTime / 1e6
	        )
	)
	f.close()


#########  RUN  ##########
def collectTiming():
	created = os.path.isfile("collect.dat")
	f = open('collect.dat', 'a')
	if not created:
		f.write("numThreads mpi omp Nspheres N M runtime \n")
	from yade import timing
	f.write(
	        str(numThreads) + " " + str(os.getenv('OMPI_COMM_WORLD_SIZE')) + " " + os.getenv('OMP_NUM_THREADS') + " " + str(N * M * (numThreads - 1)) +
	        " " + str(N) + " " + str(M) + " " + str(timing.runtime()) + "\n"
	)
	f.close()


if rank is None:  #######  Single-core  ######
	O.timingEnabled = True
	O.run(NSTEPS, True)
	#print "num bodies:",len(O.bodies)
	from yade import timing
	timing.stats()
	collectTiming()
	print "num. bodies:", len([b for b in O.bodies]), len(O.bodies)
	print "Total force on floor=", O.forces.f(WALL_ID)[1]
else:  #######  MPI  ######
	#import yade's mpi module
	from yade import mpy as mp
	# customize
	mp.ACCUMULATE_FORCES = True  #trigger force summation on master's body (here WALL_ID)
	mp.VERBOSE_OUTPUT = False
	mp.ERASE_REMOTE = True  #erase bodies not interacting wit a given subdomain?
	mp.OPTIMIZE_COM = True  #L1-optimization: pass a list of double instead of a list of states
	mp.USE_CPP_MPI = True and mp.OPTIMIZE_COM  #L2-optimization: workaround python by passing a vector<double> at the c++ level

	mp.mpirun(NSTEPS, True)
	print "num. bodies:", len([b for b in O.bodies]), len(O.bodies)
	if rank == 0:
		mp.mprint("Total force on floor=" + str(O.forces.f(WALL_ID)[1]))
		collectTimingMPI()
	else:
		mp.mprint("Partial force on floor=" + str(O.forces.f(WALL_ID)[1]))
	mp.mergeScene()
	#if rank==0: O.save('mergedScene.yade')
	mp.MPI.Finalize()
waitIfBatch()
