"""Module implementing connectivity finding."""

from __future__ import annotations

import logging

import numpy as np

from pymatgen.analysis.chemenv.connectivity.structure_connectivity import StructureConnectivity

__author__ = "David Waroquiers"
__copyright__ = "Copyright 2012, The Materials Project"
__credits__ = "Geoffroy Hautier"
__version__ = "1.0"
__maintainer__ = "David Waroquiers"
__email__ = "david.waroquiers@gmail.com"
__date__ = "June 25, 2019"

logger = logging.getLogger(__name__)


class ConnectivityFinder:
    """Main class used to find the structure connectivity of a structure."""

    def __init__(self, multiple_environments_choice=None):
        """
        Constructor for the ConnectivityFinder.

        Args:
            multiple_environments_choice: defines the procedure to apply when
            the environment of a given site is described as a "mix" of more than one
            coordination environments.
        """
        self.setup_parameters(multiple_environments_choice=multiple_environments_choice)

    def get_structure_connectivity(self, light_structure_environments):
        """Get the structure connectivity from the coordination environments provided
        as an input.

        Args:
            light_structure_environments: LightStructureEnvironments with the
            relevant coordination environments in the structure

        Returns:
            a StructureConnectivity object describing the connectivity of
        the environments in the structure
        """
        logger.info("Setup of structure connectivity graph")
        structure_connectivity = StructureConnectivity(light_structure_environments)
        structure_connectivity.add_sites()
        for site_idx, _site in enumerate(light_structure_environments.structure):
            site_neighbors_sets = light_structure_environments.neighbors_sets[site_idx]
            if site_neighbors_sets is None:
                continue
            if len(site_neighbors_sets) > 1:
                if self.multiple_environments_choice is None:
                    raise ValueError(f"Local environment of site {site_idx} is a mix and nothing is asked about it")
                if self.multiple_environments_choice == "TAKE_HIGHEST_FRACTION":
                    idx_max = np.argmax(
                        [ee["ce_fraction"] for ee in light_structure_environments.coordination_environments[site_idx]]
                    )
                    logger.info(f"IMAX {idx_max}")
                    site_neighbors_set = site_neighbors_sets[idx_max]
                else:
                    raise RuntimeError("Should not be here")
            else:
                site_neighbors_set = site_neighbors_sets[0]
            structure_connectivity.add_bonds(site_idx, site_neighbors_set)
        return structure_connectivity

    def setup_parameters(self, multiple_environments_choice):
        """Setup of the parameters for the connectivity finder."""
        if multiple_environments_choice is not None and multiple_environments_choice != "TAKE_HIGHEST_FRACTION":
            raise ValueError(f"Option {multiple_environments_choice!r} for multiple_environments_choice is not allowed")
        self.multiple_environments_choice = multiple_environments_choice
