#!/usr/bin/env python

import gudhi as gd
import argparse
import math
import numpy as np

""" This file is part of the Gudhi Library - https://gudhi.inria.fr/ -
    which is released under MIT.
    See file LICENSE or go to https://gudhi.inria.fr/licensing/ for full
    license details.
    Author(s):       Vincent Rouvreau

    Copyright (C) 2016 Inria

    Modification(s):
      - YYYY/MM Author: Description of the modification
"""

__author__ = "Vincent Rouvreau"
__copyright__ = "Copyright (C) 2016 Inria"
__license__ = "MIT"

parser = argparse.ArgumentParser(
    description="AlphaComplex and RipsComplex "
    "persistence creation from points read in "
    "a OFF file. Bottleneck distance computation"
    " on each dimension",
    epilog="Example: "
    "example/alpha_rips_persistence_bottleneck_distance.py "
    "-f ../data/points/tore3D_1307.off -t 0.15 -d 3",
)
parser.add_argument("-f", "--file", type=str, required=True)
parser.add_argument("-t", "--threshold", type=float, default=0.5)
parser.add_argument("-d", "--max_dimension", type=int, default=1)

args = parser.parse_args()
point_cloud = gd.read_points_from_off_file(off_file=args.file)
print("##############################################################")
print("RipsComplex creation from points read in a OFF file")

message = "RipsComplex with max_edge_length=" + repr(args.threshold)
print(message)

rips_complex = gd.RipsComplex(
    points=point_cloud, max_edge_length=args.threshold
)

rips_stree = rips_complex.create_simplex_tree(
    max_dimension=args.max_dimension)

message = "Number of simplices=" + repr(rips_stree.num_simplices())
print(message)

rips_stree.compute_persistence()

print("##############################################################")
print("AlphaComplex creation from points read in a OFF file")

message = "AlphaComplex with max_edge_length=" + repr(args.threshold)
print(message)

alpha_complex = gd.AlphaComplex(points=point_cloud)
alpha_stree = alpha_complex.create_simplex_tree(
    max_alpha_square=(args.threshold * args.threshold)
)

message = "Number of simplices=" + repr(alpha_stree.num_simplices())
print(message)

alpha_stree.compute_persistence()

max_b_distance = 0.0
for dim in range(args.max_dimension):
    # Alpha persistence values needs to be transform because filtration
    # values are alpha square values
    alpha_intervals = np.sqrt(alpha_stree.persistence_intervals_in_dimension(dim))

    rips_intervals = rips_stree.persistence_intervals_in_dimension(dim)
    bottleneck_distance = gd.bottleneck_distance(
        rips_intervals, alpha_intervals
    )
    message = (
        "In dimension "
        + repr(dim)
        + ", bottleneck distance = "
        + repr(bottleneck_distance)
    )
    print(message)
    max_b_distance = max(bottleneck_distance, max_b_distance)

print("==============================================================")
message = "Bottleneck distance is " + repr(max_b_distance)
print(message)