import argparse

import numpy as np

from skopt import dummy_minimize, forest_minimize, gbrt_minimize, gp_minimize
from skopt.benchmarks import branin


def run(n_calls=200, n_runs=10, acq_optimizer="lbfgs"):
    bounds = [(-5.0, 10.0), (0.0, 15.0)]
    optimizers = [
        ("gp_minimize", gp_minimize),
        ("forest_minimize", forest_minimize),
        ("gbrt_minimize", gbrt_minimize),
        ("dummy_minimize", dummy_minimize),
    ]

    for name, optimizer in optimizers:
        print(name)
        results = []
        min_func_calls = []

        for random_state in range(n_runs):
            if name == "gp_minimize":
                res = optimizer(
                    branin,
                    bounds,
                    random_state=random_state,
                    n_calls=n_calls,
                    noise=1e-10,
                    verbose=True,
                    acq_optimizer=acq_optimizer,
                    n_jobs=-1,
                )
            elif name == "dummy_minimize":
                res = optimizer(
                    branin, bounds, random_state=random_state, n_calls=n_calls
                )
            else:
                res = optimizer(
                    branin,
                    bounds,
                    random_state=random_state,
                    n_calls=n_calls,
                    acq_optimizer=acq_optimizer,
                )
            results.append(res)
            func_vals = np.round(res.func_vals, 3)
            min_func_calls.append(np.argmin(func_vals) + 1)

        optimal_values = [result.fun for result in results]
        mean_optimum = np.mean(optimal_values)
        std = np.std(optimal_values)
        best = np.min(optimal_values)
        print("Mean optimum: " + str(mean_optimum))
        print("Std of optimal values" + str(std))
        print("Best optima:" + str(best))

        mean_fcalls = np.mean(min_func_calls)
        std_fcalls = np.std(min_func_calls)
        best_fcalls = np.min(min_func_calls)
        print("Mean func_calls to reach min: " + str(mean_fcalls))
        print("Std func_calls to reach min: " + str(std_fcalls))
        print("Fastest no of func_calls to reach min: " + str(best_fcalls))


if __name__ == "__main__":
    parser = argparse.ArgumentParser()

    parser.add_argument(
        '--n_calls', nargs="?", default=50, type=int, help="Number of function calls."
    )
    parser.add_argument(
        '--n_runs', nargs="?", default=5, type=int, help="Number of runs."
    )
    parser.add_argument(
        '--acq_optimizer',
        nargs="?",
        default="lbfgs",
        type=str,
        help="Acquistion optimizer.",
    )
    args = parser.parse_args()
    run(args.n_calls, args.n_runs, args.acq_optimizer)
