#! /usr/bin/env python3

import numpy as np
import argparse
from vasppy.poscar import Poscar
from vasppy.cell import Cell
from vasppy.pimaim import get_cart_coords_from_pimaim_restart


def parse_command_line_arguments():
    parser = argparse.ArgumentParser(description="TODO")
    parser.add_argument(
        "-l", "--labels", nargs="+", help="labels for each species", required=True
    )
    parser.add_argument(
        "-n",
        "--atom-numbers",
        nargs="+",
        help="atom numbers for each species",
        required=True,
        type=int,
    )
    args = parser.parse_args()
    if len(args.labels) != len(args.atom_numbers):
        print("'labels' and 'atom-numbers' require matched argument numbers")
        exit()
    return args


def lines_to_numpy_array(data):
    return np.array([[float(s) for s in line.split()] for line in data])


def read_pimaim_restart(filename):
    with open(filename, "r") as f:
        file_data = f.readlines()
    cr_dump_log, vel_dump_log, chg_dump_log, full_dump_log = [
        bool(line.strip()) for line in file_data[:4]
    ]
    # figure out how many atoms are in this calculation
    data_per_line = [len(line.split()) for line in file_data]
    number_of_atomic_data_lines = next(
        index for index, d in enumerate(data_per_line[4:]) if d == 1
    )
    number_of_atomic_data_types = sum([cr_dump_log, vel_dump_log, chg_dump_log])
    number_of_atoms = int(number_of_atomic_data_lines / number_of_atomic_data_types)
    # this assumes coordinates, velocities, and dipoles are all present.
    # not sure what happens if atoms have qudrupoles, etc.
    coordinates = lines_to_numpy_array(file_data[4 : 4 + number_of_atoms])
    velocities = lines_to_numpy_array(
        file_data[4 + number_of_atoms : 4 + number_of_atoms * 2]
    )
    dipoles = lines_to_numpy_array(
        file_data[4 + number_of_atoms * 2 : 4 + number_of_atoms * 3]
    )
    cell_matrix = lines_to_numpy_array(file_data[-6:-3])
    cell_lengths = lines_to_numpy_array(file_data[-3:])
    full_cell_matrix = cell_matrix * cell_lengths
    return (coordinates, velocities, dipoles, full_cell_matrix, cell_lengths)


def main():
    filename = "testout.rst"
    args = parse_command_line_arguments()
    (
        coordinates,
        velocities,
        dipoles,
        full_cell_matrix,
        cell_lengths,
    ) = read_pimaim_restart(filename)
    assert sum(args.atom_numbers) == len(coordinates)
    poscar = Poscar()
    full_cell_matrix = full_cell_matrix.transpose()
    coordinates = get_cart_coords_from_pimaim_restart(
        coordinates, full_cell_matrix, cell_lengths
    )
    poscar.cell = Cell(full_cell_matrix)
    poscar.atoms = args.labels
    poscar.atom_numbers = args.atom_numbers
    poscar.coordinate_type = "Cartesian"
    poscar.coordinates = coordinates
    poscar.output()


if __name__ == "__main__":
    main()
