# -*- encoding=utf-8 -*-

# example of use JCFpm classes : Law2_ScGeom_JCFpmPhys_JointedCohesiveFrictionalPM...
# a cubic rock massif, containing a rock joint with ~ 31 deg. dip angle. At one time, the mechanical properties of the joint are degraded, triggering a smooth sliding

# definition of a predicate for use of randomDensePack() function

from yade.yexecfile import execfile

from yade import pack
dimModele = 10.0
pred = pack.inAlignedBox((0, 0, 0), (dimModele, dimModele, dimModele))

# the packing of spheres :


def mat():
	return JCFpmMat(
	        type=1,
	        young=1e8,
	        poisson=0.3,
	        frictionAngle=radians(30),
	        density=3000,
	        tensileStrength=1e6,
	        cohesion=1e6,
	        jointNormalStiffness=1e7,
	        jointShearStiffness=1e7,
	        jointCohesion=1e6,
	        jointFrictionAngle=radians(20),
	        jointDilationAngle=0.0
	)


nSpheres = 3000.0
poros = 0.13
rMeanSpheres = dimModele * pow(3.0 / 4.0 * (1 - poros) / (pi * nSpheres), 1.0 / 3.0)
print('')
print('Creating a cubic sample of spheres (may take some time and cause warnings)')
print('')
# maybe using seed=?? will fix the problem.
sp = pack.randomDensePack(pred, radius=rMeanSpheres, rRelFuzz=0.3, memoizeDb='/tmp/gts-triax-packings.sqlite', returnSpherePack=True)
sp.toSimulation(color=(0.9, 0.8, 0.6), wire=False, material=mat)
print('')
print('Sample created !')

# Definition of the facets for joint's geometry

import gts
# joint with ~ 31 deg. dip angle
v1 = gts.Vertex(0, 0, 0.8 * dimModele)
v2 = gts.Vertex(0, dimModele, 0.8 * dimModele)
v3 = gts.Vertex(dimModele, dimModele, 0.2 * dimModele)
v4 = gts.Vertex(dimModele, 0, 0.2 * dimModele)

e1 = gts.Edge(v1, v2)
e2 = gts.Edge(v2, v4)
e3 = gts.Edge(v4, v1)
f1 = gts.Face(e1, e2, e3)

e4 = gts.Edge(v4, v3)
e5 = gts.Edge(v3, v2)
f2 = gts.Face(e2, e4, e5)

s1 = gts.Surface()
s1.add(f1)
s1.add(f2)

facet = gtsSurface2Facets(s1, wire=False, material=mat)
O.bodies.append(facet)

yade.qt.View()
yade.qt.Controller()

O.saveTmp()
# identification of spheres onJoint, and so on:
execfile('identifBis.py')
dim = utils.aabbExtrema()
xsup = dim[1][0]
yinf = dim[0][1]
ysup = dim[1][1]
zinf = dim[0][2]
zsup = dim[1][2]

e = 2.5 * rMeanSpheres

refPoint = None

for o in O.bodies:
	if isinstance(o.shape, Sphere):
		o.shape.color = (0.9, 0.8, 0.6)
		## to fix boundary particles on ground
		if o.state.pos[2] < (zinf + 2 * e):
			o.state.blockedDOFs += 'xyz'
			o.shape.color = (1, 1, 1)

	## to identify indicator on top
	## FIXME - should always find something.
	if o.state.pos[2] > (zsup - e) and o.state.pos[0] > (xsup - e) and o.state.pos[1] > ((yinf + ysup - e) /
	                                                                                     2.0) and o.state.pos[1] < ((yinf + ysup + e) / 2):
		print("indicator on top: " + str(o.id))
		refPoint = o.id

if refPoint:
	O.bodies[refPoint].shape.highlight = True
else:
	print("ERROR: could not find 'indicator on top' in the randomly generated sample. Try again, or fix this script.")
	input("Press Enter to continue...")

#### Engines definition
O.engines = [
        ForceResetter(),
        InsertionSortCollider([
                Bo1_Sphere_Aabb(),
        ]),
        InteractionLoop(
                [Ig2_Sphere_Sphere_ScGeom()],
                #		[Ip2_JCFpmMat_JCFpmMat_JCFpmPhys(cohesiveTresholdIteration=1,alpha=0.3,tensileStrength=1e6,cohesion=1e6,jointNormalStiffness=1e7,jointShearStiffness=1e7,jointCohesion=1e6,jointFrictionAngle=radians(20),jointDilationAngle=0.0)],
                [Ip2_JCFpmMat_JCFpmMat_JCFpmPhys(cohesiveTresholdIteration=1)],
                [Law2_ScGeom_JCFpmPhys_JointedCohesiveFrictionalPM(smoothJoint=True)]
        ),
        GlobalStiffnessTimeStepper(timestepSafetyCoefficient=0.8),
        PyRunner(iterPeriod=1000, initRun=False, command='jointStrengthDegradation()'),
        PyRunner(iterPeriod=10, initRun=True, command='dataCollector()'),
        NewtonIntegrator(damping=0.7, gravity=(0., 0., -10.)),
]

#### dataCollector
from yade import plot
plot.plots = {'iterations': 'v', 'x': 'z'}


def dataCollector():
	R = O.bodies[refPoint]
	plot.addData(v=R.state.vel[2], z=R.state.pos[2], x=R.state.pos[0], iterations=O.iter, t=O.realtime)


#### joint strength degradation
stableIter = 1000
stableVel = 0.001
degrade = True


def jointStrengthDegradation():
	global degrade
	if degrade and O.iter >= stableIter and abs(O.bodies[refPoint].state.vel[2]) < stableVel:
		print('Equilibrium reached \nJoint cohesion canceled now !', ' | iteration=', O.iter)
		degrade = False
	for i in O.interactions:
		if i.phys.isOnJoint:
			if i.phys.isCohesive:
				i.phys.isCohesive = False
				i.phys.FnMax = 0.
				i.phys.FsMax = 0.


print('Seeking after an initial equilibrium state')
print('')
O.run(10000)
plot.plot()  # note the straight trajectory (z(x) plot)during sliding step (before free fall) despite the discretization of joint plane with spheres
