#!/usr/bin/env python3
"""
Example of simulating a reflectometry experiment
with a rough sample using BornAgain.

"""
import bornagain as ba
from bornagain import angstrom, ba_plot as bp, deg, nm


def get_sample():
    # Materials
    vacuum = ba.MaterialBySLD("Vacuum", 0, 0)
    material_ti = ba.MaterialBySLD("Ti", -1.9493e-06, 0)
    material_ni = ba.MaterialBySLD("Ni", 9.4245e-06, 0)
    material_substrate = ba.MaterialBySLD("SiSubstrate", 2.0704e-06, 0)

    # Layers
    ambient_layer = ba.Layer(vacuum)
    ti_layer = ba.Layer(material_ti, 30*angstrom)
    ni_layer = ba.Layer(material_ni, 70*angstrom)
    substrate_layer = ba.Layer(material_substrate)

    roughness = ba.LayerRoughness(1*nm)

    # Sample
    sample = ba.MultiLayer()
    sample.addLayer(ambient_layer)
    for _ in range(10):
        sample.addLayerWithTopRoughness(ti_layer, roughness)
        sample.addLayerWithTopRoughness(ni_layer, roughness)
    sample.addLayerWithTopRoughness(substrate_layer, roughness)

    return sample


def get_simulation(sample):
    n = 50
    scan = ba.AlphaScan(n, 2*deg/n, 2*deg)
    scan.setWavelength(1.54*angstrom)
    return ba.SpecularSimulation(scan, sample)


if __name__ == '__main__':
    sample = get_sample()
    simulation = get_simulation(sample)
    result = simulation.simulate()
    bp.plot_simulation_result(result)
    bp.show_or_export()
