"""Run parallel shallow water domain.

   run using command like:

   mpirun -np m python run_parallel_sw_merimbula.py

   where m is the number of processors to be used.
   
   Will produce sww files with names domain_Pn_m.sww where m is number of processors and
   n in [0, m-1] refers to specific processor that owned this part of the partitioned mesh.
"""

#------------------------------------------------------------------------------
# Import necessary modules
#------------------------------------------------------------------------------

import os
import sys
import time
import numpy as num

#------------------------
# ANUGA Modules
#------------------------
	
from anuga import Domain
from anuga import Reflective_boundary
from anuga import Dirichlet_boundary
from anuga import Time_boundary
from anuga import Transmissive_boundary

from anuga import rectangular_cross
from anuga import create_domain_from_file


from anuga_parallel import distribute, myid, numprocs, finalize, barrier


#--------------------------------------------------------------------------
# Setup parameters
#--------------------------------------------------------------------------

#mesh_filename = "merimbula_10785_1.tsh" ; x0 = 756000.0 ; x1 = 756500.0
#mesh_filename = "merimbula_43200.tsh"   ; x0 = 756000.0 ; x1 = 756500.0
mesh_filename = "test-100.tsh" ; x0 = 0.25 ; x1 = 0.5
yieldstep = 20
finaltime = 500
verbose = True

#--------------------------------------------------------------------------
# Setup procedures
#--------------------------------------------------------------------------
class Set_Stage:
    """Set an initial condition with constant water height, for x0<x<x1
    """

    def __init__(self, x0=0.25, x1=0.5, h=1.0):
        self.x0 = x0
        self.x1 = x1
        self.h  = h

    def __call__(self, x, y):
        return self.h*((x>self.x0)&(x<self.x1))

#--------------------------------------------------------------------------
# Setup Domain only on processor 0
#--------------------------------------------------------------------------
if myid == 0:
    domain = create_domain_from_file(mesh_filename)
    domain.set_quantity('stage', Set_Stage(x0, x1, 2.0))

    print domain.statistics()
    print domain.get_extent()
    print domain.get_extent(absolute=True)
    print domain.geo_reference
else:
    domain = None

#--------------------------------------------------------------------------
# Distribute sequential domain on processor 0 to other processors
#--------------------------------------------------------------------------

if myid == 0 and verbose: print 'DISTRIBUTING DOMAIN'
domain = distribute(domain)

#domain.smooth = False

domain.set_default_order(2)
domain.set_timestepping_method('rk2')
#domain.set_CFL(0.7)
#domain.set_beta(1.5)
domain.set_name('merimbula')

for p in range(numprocs):
    if myid == p:
        print 'P%d'%p
        print domain.get_extent()
        print domain.get_extent(absolute=True)
        print domain.geo_reference
        #print domain.tri_map
        #print domain.inv_tri_map
        print domain.tri_l2g
        print domain.node_l2g
    else:
        pass
    
    barrier()


#------------------------------------------------------------------------------
# Setup boundary conditions
# This must currently happen *after* domain has been distributed
#------------------------------------------------------------------------------
Br = Reflective_boundary(domain)      # Solid reflective wall

domain.set_boundary({'outflow' :Br, 'inflow' :Br, 'inner' :Br, 'exterior' :Br, 'open' :Br})

#------------------------------------------------------------------------------
# Evolution
#------------------------------------------------------------------------------
if myid == 0 and verbose: print 'EVOLVE'

t0 = time.time()

for t in domain.evolve(yieldstep = yieldstep, finaltime = finaltime):
    if myid == 0:
        domain.write_time()


if myid == 0:
    print 'Number of processors %g ' %numprocs
    print 'That took %.2f seconds' %(time.time()-t0)
    print 'Communication time %.2f seconds'%domain.communication_time
    print 'Reduction Communication time %.2f seconds'%domain.communication_reduce_time
    print 'Broadcast time %.2f seconds'%domain.communication_broadcast_time


#--------------------------------------------------
# Merge the individual sww files into one file
#--------------------------------------------------
domain.sww_merge()

finalize()