import numpy

from refl1d.names import *

chrome = Material("Cr")
gold = Material("Au")
solvent = Material("H2O", density=1)


wrap = SLD(name="wrap", rho=0)

n1, n2, n3 = 3, 9, 3

tether = FreeLayer(
    below=gold, above=wrap, thickness=10, z=numpy.linspace(0, 1, n1 + 2)[1:-1], rho=numpy.random.rand(n1), name="tether"
)
bilayer = FreeLayer(
    below=wrap,
    above=wrap,
    thickness=80,
    z=numpy.linspace(0, 1, n2 + 2)[1:-1],
    rho=5 * numpy.random.rand(n2) - 1,
    name="bilayer",
)
tail = FreeLayer(
    below=wrap,
    above=solvent,
    thickness=10,
    z=numpy.linspace(0, 1, n3 + 2)[1:-1],
    rho=numpy.random.rand(n3),
    name="tail",
)

sample = silicon(0, 5) | chrome(20, 2) | gold(50, 5) | tether | bilayer * 10 | tail | solvent

T = numpy.linspace(0, 5, 100)
probe = NeutronProbe(T=T, dT=0.01, L=4.75, dL=0.0475, back_reflectivity=True)
M = Experiment(probe=probe, sample=sample, dA=5)
M.simulate_data(5)
problem = FitProblem(M)