#!/usr/bin/env amspython
import numpy as np
from scm.plams import Units


def get_values():
    E_eV = np.array([1.7576, 1.7581, 1.7587])
    D = np.array([4.6005, 26.599, 196.61])
    R = np.array([-0.34615e-1, -0.35678e-1, 0.10183])
    tau = np.array([0.2433e-2, 0.4205e-3, 0.5683e-4])
    refractive_index = 1
    return E_eV, R, D, tau, refractive_index


def main():
    E_eV, R, D, tau, refractive_index = get_values()

    use_boltzmann_weights = False

    if use_boltzmann_weights:
        weights = calc_boltzmann_weights(E_eV, T=298)
    else:
        weights = np.ones(np.shape(E_eV))

    g = 4 * np.dot(R, weights) / np.dot(D, weights)
    print(f"g_lum_av: {g:.3e}")

    tau_av = 1.0 / refractive_index**2 * np.sum(weights) / np.dot(1.0 / tau, weights)
    print(f"tau_av: {tau_av:.3e} s")


def calc_boltzmann_weights(E_eV, T=298):
    k_B = Units.constants["k_B"] * Units.convert(1, "J", "eV")  # eV/K
    boltzmann_weights = np.exp(-(E_eV - np.min(E_eV)) / (k_B * T))
    return boltzmann_weights


if __name__ == "__main__":
    main()