"""
==========================================
:mod:`orso` ORSO standard file data loader
==========================================

Loads the format following the specification of the Open Reflectometry Standards Organization (ORSO).
See https://www.reflectometry.org/working_groups/file_formats/ for more details
"""

import re

from typing import List

import h5py
import numpy as np

from orsopy.fileio import OrsoDataset, load_nexus, load_orso

from ..data_loader_framework import Template
from ..utils import ShowWarningDialog


class Plugin(Template):
    wildcard = "*.ort;*.orb;*.nxs;*.h5;*.hdf"
    _cached_file = ""
    _cached_data: List[OrsoDataset] = None

    def __init__(self, parent):
        Template.__init__(self, parent)
        self.x_col = 0
        self.y_col = 1
        self.e_col = 3
        self.xe_col = 2
        self.comment = "#"
        self.skip_rows = 0
        self.delimiter = None

    def CanOpen(self, file_path):
        if not Template.CanOpen(self, file_path):
            return False
        if (
            file_path.endswith(".orb")
            or file_path.endswith(".nxs")
            or file_path.endswith(".h5")
            or file_path.endswith(".hdf")
        ):
            return h5py.is_hdf5(file_path)
        else:
            l1 = open(file_path, "r", encoding="utf-8").readline()
            return l1.startswith("# # ORSO")

    def LoadCached(self, file_path):
        if self._cached_file == file_path:
            return self._cached_data
        else:
            if (
                file_path.endswith(".orb")
                or file_path.endswith(".nxs")
                or file_path.endswith(".h5")
                or file_path.endswith(".hdf")
            ):
                orso_datasets = load_nexus(file_path)
            else:
                orso_datasets = load_orso(file_path)
            self._cached_file = file_path
            self._cached_data = orso_datasets
            return orso_datasets

    def CountDatasets(self, file_path):
        try:
            orso_datasets = self.LoadCached(file_path)
        except Exception as e:
            return 1
        else:
            return len(orso_datasets)

    def LoadData(self, dataset, filename, data_id=0):
        """
        Loads the data from filename into the data_item_number.
        """
        try:
            orso_datasets = self.LoadCached(filename)
        except Exception as e:
            ShowWarningDialog(
                self.parent,
                "Could not load the file: "
                + filename
                + " \nPlease check the format.\n\n ORSO reader gave the following error:\n"
                + str(e),
            )
            return
        else:
            orso_dataset: OrsoDataset = orso_datasets[data_id]
            data: np.ndarray = orso_dataset.data.T

            cols = orso_dataset.info.columns

            start_usercols = 3
            dataset.x_raw = np.asarray(data[0])
            if orso_dataset.info.columns[0].unit == "1/nm":
                dataset.x_raw /= 10.0
            dataset.y_raw = np.asarray(data[1])
            dataset.error_raw = np.asarray(data[2])
            if data.shape[0] > 3 and getattr(cols[3], "error_of", None) == cols[0].name:
                start_usercols = 4
                dataset.set_extra_data("res", np.asarray(data[3]) * cols[3].to_sigma, "res")
            for i, col in enumerate(data[start_usercols:]):
                colname = cols[i + start_usercols].name
                if not colname.isidentifier() or colname in ["lambda", "x", "y", "error", "res"]:
                    colname = "col_" + re.sub("[^0-9a-zA-Z_]", "", colname)
                dataset.set_extra_data(colname, np.asarray(col), colname)
            # Name the dataset accordign to file name
            if orso_dataset.info.data_set:
                dataset.name = str(orso_dataset.info.data_set)
            # Run the commands on the data - this also sets the x,y, error memebers
            # of that data item.
            dataset.run_command()

            # insert metadata into ORSO compatible fields
            dataset.meta = orso_dataset.info.to_dict()
            if "data_set" in dataset.meta:
                del dataset.meta["data_set"]
