field_setting_parser.py

"""
This module allows to extract from a YAML file the values to write in an ÉTS
club expense report. The YAML file must comply with the format of those
provided in this repository. If this module is executed and given the path to
a YAML file as an argument, it will print the name of the report's fields in
the console with the value they are assigned.
"""


from pathlib import Path
from yaml import FullLoader, load


_CHECKBOX_YES = "/Oui"
_KEY_CHECKED = "Cochée"


def _dict_key_val_str(key, value):
	"""
	Creates a string representing a dictionary item. The string fits the
	format "<key>: <value>".

	Args:
		key: the key from the dictionary item
		value: the value from the dictionary item

	Returns:
		str: a string representing the dictionary item
	"""
	return str(key) + ": " + str(value)


def _dict_key_val_type_str(key, value):
	"""
	Creates a string representing a dictionary item. The string fits this
	format: "<key>: <value> <type(value)>".

	Args:
		key: the key from the dictionary item
		value: the value from the dictionary item

	Returns:
		str: a string representing the dictionary item
	"""
	return _dict_key_val_str(key, value) + " " + str(type(value))


def _error_for_unexpected_value(key, value):
	raise ValueError("Unexpected value for " + str(key) + ": " + str(value))


def filter_values_from_dict(a_dict, unwanted_vals):
	"""
	Creates a dictionary containing the items from a_dict minus those whose
	value is in unwanted_vals. a_dict is not modified.

	Args:
		a_dict (dict): any dictionary
		unwanted_vals: a list, set or tuple containing the values to filter

	Returns:
		dict: a dictionary containing the items of a_dict except the unwanted
		values
	"""
	wanted_items = dict()

	for key, value in a_dict.items():
		if value not in unwanted_vals:
			wanted_items[key] = value

	return wanted_items


def get_yaml_content(yaml_file_path):
	"""
	Reads a YAML file and returns its content in in a dictionary.

	Args:
		yaml_file_path (pathlib.Path): the path to a YAML file

	Returns:
		dict: the YAML file's content

	Raises:
		ValueError: if the extension of field_setting_path is not "yaml" or
		"yml"
	"""
	if yaml_file_path.suffixes not in ([".yaml"], [".yml"]):
		raise ValueError("The file extension must be \".yaml\" or \".yml\".")

	with yaml_file_path.open(encoding="utf8") as field_setting_stream:
		yaml_content = load(field_setting_stream, FullLoader)

	if yaml_content is None:
		yaml_content = dict()

	return yaml_content


def _parse_codes_comptables(codes_comptables):
	fields = dict()

	for i in range(len(codes_comptables)):
		cc = codes_comptables[i]

		ubr = cc.get("UBR")
		if ubr is not None:
			fields["UBR" + str(i+1)] = ubr

		account = cc.get("Compte")
		if account is not None:
			fields["CC" + str(i+1)] = account

		df = cc.get("DemFin")
		if df is not None:
			fields["DF" + str(i+1)] = df

		cbs = cc.get("CBS")
		if cbs is not None:
			fields["CBS" + str(i+1)] = cbs

		amount = cc.get("Montant")
		if amount is not None:
			fields["ccMontant$" + str(i+1)] = amount

	return fields


def _parse_expense_list(expense_list):
	fields = dict()

	for i, expense in enumerate(expense_list):
		if (description := expense.get("Description")) is not None:
			fields["Détails" + str(i+1)] = description

		amount = expense.get("Montant")
		if amount is not None:
			fields["Montant$" + str(i+1)] = amount

	return fields


def _parse_travel_reasons(travel_reason_dict):
	fields = dict()

	presentation = travel_reason_dict.get("Présentation")
	if presentation is not None:
		presentation_checked = presentation.get(_KEY_CHECKED)

		if presentation_checked:
			fields["Boite1"] = _CHECKBOX_YES

		presentation_subject = presentation.get("Sujet")

		if presentation_subject is not None:
			fields["Présentation"] = presentation_subject

	conference = travel_reason_dict.get("Conférence")
	if conference is not None:
		conference_checked = conference.get(_KEY_CHECKED)

		if conference_checked:
			fields["Boite2"] = _CHECKBOX_YES

		conference_name = conference.get("Nom")

		if conference_name is not None:
			fields["Conférence"] = conference_name

	sabbatical = travel_reason_dict.get("Sabbatique")
	if sabbatical:
		fields["Boite3"] = _CHECKBOX_YES

	others = travel_reason_dict.get("Autres")
	if others is not None:
		others_checked = others.get(_KEY_CHECKED)

		if others_checked:
			fields["Boite4"] = _CHECKBOX_YES

		others_precision = others.get("Précision")

		if others_precision is not None:
			fields["Autres"] = others_precision

	return fields


def parse_yaml_content(yaml_content):
	"""
	Parses the content that function get_yaml_content has extracted from a
	YAML file and translates it to a dictionary that matches the data with the
	fields of expense report rapport_depenses.pdf.

	Args:
		yaml_content (dict): content of a YAML file returned by
			get_yaml_content

	Returns:
		dict: a dictionary matching the data from the YAML file with the
			fields of the expense report.
	"""
	# Function update_page_fields from library PyPDF2_Fields must be able to
	# process the dictionary returned by this function.
	field_values = dict()

	for key, value in yaml_content.items():
		if key == "RaisonVoyage" and value is not None:
			field_values.update(_parse_travel_reasons(value))

		elif key == "Dépenses" and value is not None:
			field_values.update(_parse_expense_list(value))

		elif key == "Codes comptables" and value is not None:
			field_values.update(_parse_codes_comptables(value))

		elif key == "RaisonDépenses" and value is not None:
			field_values["Group1"] = value

		elif key == "Statut" and value is not None:
			field_values["Group2"] = value

		elif key == "ModePaiement" and value is not None:
			field_values["Group4"] = value

		elif key == "Distance" and value is not None:
			field_values["KM"] = value

		elif value is not None:
			field_values[key] = value

	return field_values


def print_dictionary(a_dict, print_val_type):
	"""
	Prints a dictionary's items in the console in the following format:
	"<key>: <value>".

	Args:
		a_dict (dict): any dictionary
		print_val_type (bool): if True, the type of each value is also printed.
	"""
	item_to_str_fnc = _dict_key_val_type_str if print_val_type\
		else _dict_key_val_str

	for key, value in a_dict.items():
		print(item_to_str_fnc(key, value))


def str_to_bool(bool_str):
	"""
	Converts a string to a Boolean value.

	False: "0", "f", "false", "n" or "no"

	True: "1", "t", "true", "y" or "yes"

	Args:
		bool_str (str): a string corresponding to a Boolean value

	Returns:
		bool: the Boolean value matching bool_str

	Raises:
		ValueError: if bool_str does not match a boolean value
	"""
	if bool_str.lower() in ("0", "f", "false", "n", "no"):
		return False

	if bool_str.lower() in ("1", "t", "true", "y", "yes"):
		return True

	raise ValueError("\"" + str(bool_str)
		+ "\" does not match a boolean value.")


if __name__ == "__main__":
	from argparse import ArgumentParser
	from path_arg_checks import check_ungenerable_path

	parser = ArgumentParser(description=__doc__)

	parser.add_argument("-f", "--file", type=Path, required=True,
		help="the path to a YAML file that defines values to put in the fields of an expense report")

	parser.add_argument("-t", "--types", action="store_true",
		help="If this argument is given, the type of the fields' value will be printed.")

	args = parser.parse_args()

	field_setting_path = args.file
	print_val_type = args.types

	check_ungenerable_path(
		field_setting_path, "-f/--file", ".yml", must_exist=True)

	yaml_content = get_yaml_content(field_setting_path)
	field_values = parse_yaml_content(yaml_content)
	print_dictionary(field_values, print_val_type)