# ==================================================================================================================== #
#             _____           _ _               ____ _     ___    _    _         _                  _   _              #
#  _ __  _   |_   _|__   ___ | (_)_ __   __ _  / ___| |   |_ _|  / \  | |__  ___| |_ _ __ __ _  ___| |_(_) ___  _ __   #
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# | |_) | |_| || | (_) | (_) | | | | | | (_| || |___| |___ | | / ___ \| |_) \__ \ |_| | | (_| | (__| |_| | (_) | | | | #
# | .__/ \__, ||_|\___/ \___/|_|_|_| |_|\__, (_)____|_____|___/_/   \_\_.__/|___/\__|_|  \__,_|\___|\__|_|\___/|_| |_| #
# |_|    |___/                          |___/                                                                          #
# ==================================================================================================================== #
# Authors:                                                                                                             #
#   Patrick Lehmann                                                                                                    #
#                                                                                                                      #
# License:                                                                                                             #
# ==================================================================================================================== #
# Copyright 2017-2024 Patrick Lehmann - Bötzingen, Germany                                                             #
# Copyright 2014-2016 Technische Universität Dresden - Germany, Chair of VLSI-Design, Diagnostics and Architecture     #
#                                                                                                                      #
# Licensed under the Apache License, Version 2.0 (the "License");                                                      #
# you may not use this file except in compliance with the License.                                                     #
# You may obtain a copy of the License at                                                                              #
#                                                                                                                      #
#   http://www.apache.org/licenses/LICENSE-2.0                                                                         #
#                                                                                                                      #
# Unless required by applicable law or agreed to in writing, software                                                  #
# distributed under the License is distributed on an "AS IS" BASIS,                                                    #
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.                                             #
# See the License for the specific language governing permissions and                                                  #
# limitations under the License.                                                                                       #
#                                                                                                                      #
# SPDX-License-Identifier: Apache-2.0                                                                                  #
# ==================================================================================================================== #
#
"""
This module implements command line arguments without prefix character(s).


"""
from abc     import abstractmethod
from pathlib import Path
from typing  import ClassVar, List, Union, Iterable, TypeVar, Generic, Any, Optional as Nullable

try:
	from pyTooling.Decorators  import export, readonly
except (ImportError, ModuleNotFoundError):  # pragma: no cover
	print("[pyTooling.Versioning] Could not import from 'pyTooling.*'!")

	try:
		from Decorators          import export, readonly
	except (ImportError, ModuleNotFoundError) as ex:  # pragma: no cover
		print("[pyTooling.Versioning] Could not import directly!")
		raise ex


__all__ = ["ValueT"]


ValueT = TypeVar("ValueT")   #: The type of value in a valued argument.


@export
class CommandLineArgument:
	"""
	Base-class for all *Argument* classes.

	An argument instance can be converted via ``AsArgument`` to a single string value or a sequence of string values
	(tuple) usable e.g. with :class:`subprocess.Popen`. Each argument class implements at least one ``pattern`` parameter
	to specify how argument are formatted.

	There are multiple derived formats supporting:

	* commands |br|
	  |rarr| :mod:`~pyTooling.CLIAbstraction.Command`
	* simple names (flags) |br|
	  |rarr| :mod:`~pyTooling.CLIAbstraction.Flag`, :mod:`~pyTooling.CLIAbstraction.BooleanFlag`
	* simple values (vlaued flags) |br|
	  |rarr| :class:`~pyTooling.CLIAbstraction.Argument.StringArgument`, :class:`~pyTooling.CLIAbstraction.Argument.PathArgument`
	* names and values |br|
	  |rarr| :mod:`~pyTooling.CLIAbstraction.ValuedFlag`, :mod:`~pyTooling.CLIAbstraction.OptionalValuedFlag`
	* key-value pairs |br|
	  |rarr| :mod:`~pyTooling.CLIAbstraction.NamedKeyValuePair`
	"""

	_pattern: ClassVar[str]

	def __init_subclass__(cls, *args: Any, pattern: Nullable[str] = None, **kwargs: Any):
		"""This method is called when a class is derived.

		:param args: Any positional arguments.
		:param pattern: This pattern is used to format an argument.
		:param kwargs: Any keyword argument.
		"""
		super().__init_subclass__(*args, **kwargs)
		cls._pattern = pattern

	def __new__(cls, *args: Any, **kwargs: Any):
		if cls is CommandLineArgument:
			raise TypeError(f"Class '{cls.__name__}' is abstract.")

		# TODO: not sure why parameters meant for __init__ do reach this level and distract __new__ from it's work
		return super().__new__(cls)

	# TODO: Add property to read pattern

	@abstractmethod
	def AsArgument(self) -> Union[str, Iterable[str]]:  # type: ignore[empty-body]
		"""
		Convert this argument instance to a string representation with proper escaping using the matching pattern based on
		the internal name and value.

		:return:                     Formatted argument.
		:raises NotImplementedError: This is an abstract method and must be overwritten by a subclass.
		"""
		raise NotImplementedError(f"Method 'AsArgument' is an abstract method and must be implemented by a subclass.")

	@abstractmethod
	def __str__(self) -> str:  # type: ignore[empty-body]
		"""
		Return a string representation of this argument instance.

		:return:                     Argument formatted and enclosed in double quotes.
		:raises NotImplementedError: This is an abstract method and must be overwritten by a subclass.
		"""
		raise NotImplementedError(f"Method '__str__' is an abstract method and must be implemented by a subclass.")

	@abstractmethod
	def __repr__(self) -> str:  # type: ignore[empty-body]
		"""
		Return a string representation of this argument instance.

		.. note:: By default, this method is identical to :meth:`__str__`.

		:return:                     Argument formatted and enclosed in double quotes.
		:raises NotImplementedError: This is an abstract method and must be overwritten by a subclass.
		"""
		raise NotImplementedError(f"Method '__repr__' is an abstract method and must be implemented by a subclass.")


@export
class ExecutableArgument(CommandLineArgument):
	"""
	Represents the executable.
	"""

	_executable: Path

	def __init__(self, executable: Path) -> None:
		"""
		Initializes a ExecutableArgument instance.

		:param executable: Path to the executable.
		:raises TypeError: If parameter 'executable' is not of type :class:`~pathlib.Path`.
		"""
		if not isinstance(executable, Path):
			raise TypeError("Parameter 'executable' is not of type 'Path'.")

		self._executable = executable

	@property
	def Executable(self) -> Path:
		"""
		Get the internal path to the wrapped executable.

		:return: Internal path to the executable.
		"""
		return self._executable

	@Executable.setter
	def Executable(self, value):
		"""
		Set the internal path to the wrapped executable.

		:param value:      Value to path to the executable.
		:raises TypeError: If value is not of type :class:`~pathlib.Path`.
		"""
		if not isinstance(value, Path):
			raise TypeError("Parameter 'value' is not of type 'Path'.")

		self._executable = value

	def AsArgument(self) -> Union[str, Iterable[str]]:
		"""
		Convert this argument instance to a string representation with proper escaping using the matching pattern based on
		the internal path to the wrapped executable.

		:return: Formatted argument.
		"""
		return f"{self._executable}"

	def __str__(self) -> str:
		"""
		Return a string representation of this argument instance.

		:return: Argument formatted and enclosed in double quotes.
		"""
		return f"\"{self._executable}\""

	__repr__ = __str__


@export
class DelimiterArgument(CommandLineArgument, pattern="--"):
	"""
	Represents a delimiter symbol like ``--``.
	"""

	def __init_subclass__(cls, *args: Any, pattern: str = "--", **kwargs: Any):
		"""
		This method is called when a class is derived.

		:param args:    Any positional arguments.
		:param pattern: This pattern is used to format an argument. Default: ``"--"``.
		:param kwargs:  Any keyword argument.
		"""
		kwargs["pattern"] = pattern
		super().__init_subclass__(*args, **kwargs)

	def AsArgument(self) -> Union[str, Iterable[str]]:
		"""
		Convert this argument instance to a string representation with proper escaping using the matching pattern.

		:return: Formatted argument.
		"""
		return self._pattern

	def __str__(self) -> str:
		"""
		Return a string representation of this argument instance.

		:return: Argument formatted and enclosed in double quotes.
		"""
		return f"\"{self._pattern}\""

	__repr__ = __str__


@export
class NamedArgument(CommandLineArgument, pattern="{0}"):
	"""
	Base-class for all command line arguments with a name.
	"""

	_name: ClassVar[str]

	def __init_subclass__(cls, *args: Any, name: Nullable[str] = None, pattern: str = "{0}", **kwargs: Any):
		"""
		This method is called when a class is derived.

		:param args:    Any positional arguments.
		:param name:    Name of the argument.
		:param pattern: This pattern is used to format an argument.
		:param kwargs:  Any keyword argument.
		"""
		kwargs["pattern"] = pattern
		super().__init_subclass__(*args, **kwargs)
		cls._name = name

	def __new__(cls, *args: Any, **kwargs: Any):
		if cls is NamedArgument:
			raise TypeError(f"Class '{cls.__name__}' is abstract.")
		return super().__new__(cls, *args, **kwargs)

	@readonly
	def Name(self) -> str:
		"""
		Get the internal name.

		:return: Internal name.
		"""
		return self._name

	def AsArgument(self) -> Union[str, Iterable[str]]:
		"""
		Convert this argument instance to a string representation with proper escaping using the matching pattern based on
		the internal name.

		:return:            Formatted argument.
		:raises ValueError: If internal name is None.
		"""
		if self._name is None:
			raise ValueError(f"Internal value '_name' is None.")

		return self._pattern.format(self._name)

	def __str__(self) -> str:
		"""
		Return a string representation of this argument instance.

		:return: Argument formatted and enclosed in double quotes.
		"""
		return f"\"{self.AsArgument()}\""

	__repr__ = __str__


@export
class ValuedArgument(CommandLineArgument, Generic[ValueT], pattern="{0}"):
	"""
	Base-class for all command line arguments with a value.
	"""

	_value: ValueT

	def __init_subclass__(cls, *args: Any, pattern: str = "{0}", **kwargs: Any):
		"""
		This method is called when a class is derived.

		:param args:    Any positional arguments.
		:param pattern: This pattern is used to format an argument.
		:param kwargs:  Any keyword argument.
		"""
		kwargs["pattern"] = pattern
		super().__init_subclass__(*args, **kwargs)

	def __init__(self, value: ValueT) -> None:
		"""
		Initializes a ValuedArgument instance.

		:param value:      Value to be stored internally.
		:raises TypeError: If parameter 'value' is None.
		"""
		if value is None:
			raise TypeError("Parameter 'value' is None.")

		self._value = value

	@property
	def Value(self) -> ValueT:
		"""
		Get the internal value.

		:return: Internal value.
		"""
		return self._value

	@Value.setter
	def Value(self, value: ValueT) -> None:
		"""
		Set the internal value.

		:param value:       Value to set.
		:raises ValueError: If value to set is None.
		"""
		if value is None:
			raise ValueError(f"Value to set is None.")

		self._value = value

	def AsArgument(self) -> Union[str, Iterable[str]]:
		"""
		Convert this argument instance to a string representation with proper escaping using the matching pattern based on
		the internal value.

		:return: Formatted argument.
		"""
		return self._pattern.format(self._value)

	def __str__(self) -> str:
		"""
		Return a string representation of this argument instance.

		:return: Argument formatted and enclosed in double quotes.
		"""
		return f"\"{self.AsArgument()}\""

	__repr__ = __str__


class NamedAndValuedArgument(NamedArgument, ValuedArgument, Generic[ValueT], pattern="{0}={1}"):
	"""
	Base-class for all command line arguments with a name and a value.
	"""

	def __init_subclass__(cls, *args: Any, name: Nullable[str] = None, pattern: str = "{0}={1}", **kwargs: Any):
		"""
		This method is called when a class is derived.

		:param args:    Any positional arguments.
		:param name:    Name of the argument.
		:param pattern: This pattern is used to format an argument.
		:param kwargs:  Any keyword argument.
		"""
		kwargs["name"] = name
		kwargs["pattern"] = pattern
		super().__init_subclass__(*args, **kwargs)
		del kwargs["name"]
		del kwargs["pattern"]
		ValuedArgument.__init_subclass__(*args, **kwargs)

	def __init__(self, value: ValueT) -> None:
		ValuedArgument.__init__(self, value)

	def AsArgument(self) -> Union[str, Iterable[str]]:
		"""
		Convert this argument instance to a string representation with proper escaping using the matching pattern based on
		the internal name and value.

		:return:            Formatted argument.
		:raises ValueError: If internal name is None.
		"""
		if self._name is None:
			raise ValueError(f"Internal value '_name' is None.")

		return self._pattern.format(self._name, self._value)

	def __str__(self) -> str:
		"""
		Return a string representation of this argument instance.

		:return: Argument formatted and enclosed in double quotes.
		"""
		return f"\"{self.AsArgument()}\""

	__repr__ = __str__


class NamedTupledArgument(NamedArgument, ValuedArgument, Generic[ValueT], pattern="{0}"):
	"""
	Class and base-class for all TupleFlag classes, which represents an argument with separate value.

	A tuple argument is a command line argument followed by a separate value. Name and value are passed as two arguments
	to the executable.

	**Example: **

	* `width 100``
	"""

	_valuePattern: ClassVar[str]

	def __init_subclass__(cls, *args: Any, name: Nullable[str] = None, pattern: str = "{0}", valuePattern: str = "{0}", **kwargs: Any):
		kwargs["name"] = name
		kwargs["pattern"] = pattern
		super().__init_subclass__(*args, **kwargs)
		cls._valuePattern = valuePattern

	def __new__(cls, *args: Any, **kwargs: Any):
		if cls is NamedTupledArgument:
			raise TypeError(f"Class '{cls.__name__}' is abstract.")
		return super().__new__(cls, *args, **kwargs)

	def __init__(self, value: ValueT) -> None:
		ValuedArgument.__init__(self, value)

	# TODO: Add property to read value pattern

	# @property
	# def ValuePattern(self) -> str:
	# 	if self._valuePattern is None:
	# 		raise ValueError(f"")  # XXX: add message
	#
	# 	return self._valuePattern

	def AsArgument(self) -> Union[str, Iterable[str]]:
		"""
		Convert this argument instance to a sequence of string representations with proper escaping using the matching
		pattern based on the internal name and value.

		:return:            Formatted argument as tuple of strings.
		:raises ValueError: If internal name is None.
		"""
		if self._name is None:
			raise ValueError(f"Internal value '_name' is None.")

		return (
			self._pattern.format(self._name),
			self._valuePattern.format(self._value)
		)

	def __str__(self) -> str:
		"""
		Return a string representation of this argument instance.

		:return: Space separated sequence of arguments formatted and each enclosed in double quotes.
		"""
		return " ".join([f"\"{item}\"" for item in self.AsArgument()])

	def __repr__(self) -> str:
		"""
		Return a string representation of this argument instance.

		:return: Comma separated sequence of arguments formatted and each enclosed in double quotes.
		"""
		return ", ".join([f"\"{item}\"" for item in self.AsArgument()])


@export
class StringArgument(ValuedArgument, pattern="{0}"):
	"""
	Represents a simple string argument.

	A list of strings is available as :class:`~pyTooling.CLIAbstraction.Argument.StringListArgument`.
	"""

	def __init_subclass__(cls, *args: Any, pattern: str = "{0}", **kwargs: Any):
		"""
		This method is called when a class is derived.

		:param args:    Any positional arguments.
		:param pattern: This pattern is used to format an argument.
		:param kwargs:  Any keyword argument.
		"""
		kwargs["pattern"] = pattern
		super().__init_subclass__(*args, **kwargs)


@export
class StringListArgument(ValuedArgument):
	"""
	Represents a list of string argument (:class:`~pyTooling.CLIAbstraction.Argument.StringArgument`)."""

	def __init__(self, values: Iterable[str]) -> None:
		"""
		Initializes a StringListArgument instance.

		:param values:     An iterable of str instances.
		:raises TypeError: If iterable parameter 'values' contains elements not of type :class:`str`.
		"""
		self._values = []
		for value in values:
			if not isinstance(value, str):
				raise TypeError(f"Parameter 'values' contains elements which are not of type 'str'.")

			self._values.append(value)

	@property
	def Value(self) -> List[str]:
		"""
		Get the internal list of str objects.

		:return: Reference to the internal list of str objects.
		"""
		return self._values

	@Value.setter
	def Value(self, value: Iterable[str]):
		"""
		Overwrite all elements in the internal list of str objects.

		.. note:: The list object is not replaced, but cleared and then reused by adding the given elements in the iterable.

		:param value:      List of str objects to set.
		:raises TypeError: If value contains elements, which are not of type :class:`str`.
		"""
		self._values.clear()
		for value in value:
			if not isinstance(value, str):
				raise TypeError(f"Value contains elements which are not of type 'str'.")
			self._values.append(value)

	def AsArgument(self) -> Union[str, Iterable[str]]:
		"""
		Convert this argument instance to a string representation with proper escaping using the matching pattern based on
		the internal value.

		:return: Sequence of formatted arguments.
		"""
		return [f"{value}" for value in self._values]

	def __str__(self) -> str:
		"""
		Return a string representation of this argument instance.

		:return: Space separated sequence of arguments formatted and each enclosed in double quotes.
		"""
		return " ".join([f"\"{value}\"" for value in self.AsArgument()])

	def __repr__(self) -> str:
		"""
		Return a string representation of this argument instance.

		:return: Comma separated sequence of arguments formatted and each enclosed in double quotes.
		"""
		return ", ".join([f"\"{value}\"" for value in self.AsArgument()])


# TODO: Add option to class if path should be checked for existence
@export
class PathArgument(CommandLineArgument):
	"""
	Represents a single path argument.

	A list of paths is available as :class:`~pyTooling.CLIAbstraction.Argument.PathListArgument`.
	"""
	# The output format can be forced to the POSIX format with :py:data:`_PosixFormat`.
	_path: Path

	def __init__(self, path: Path) -> None:
		"""
		Initializes a PathArgument instance.

		:param path:       Path to a filesystem object.
		:raises TypeError: If parameter 'path' is not of type :class:`~pathlib.Path`.
		"""
		if not isinstance(path, Path):
			raise TypeError("Parameter 'path' is not of type 'Path'.")
		self._path = path

	@property
	def Value(self) -> Path:
		"""
		Get the internal path object.

		:return: Internal path object.
		"""
		return self._path

	@Value.setter
	def Value(self, value: Path):
		"""
		Set the internal path object.

		:param value:      Value to set.
		:raises TypeError: If value is not of type :class:`~pathlib.Path`.
		"""
		if not isinstance(value, Path):
			raise TypeError("Parameter 'value' is not of type 'Path'.")

		self._path = value

	def AsArgument(self) -> Union[str, Iterable[str]]:
		"""
		Convert this argument instance to a string representation with proper escaping using the matching pattern based on
		the internal value.

		:return: Formatted argument.
		"""
		return f"{self._path}"

	def __str__(self) -> str:
		"""
		Return a string representation of this argument instance.

		:return: Argument formatted and enclosed in double quotes.
		"""
		return f"\"{self._path}\""

	__repr__ = __str__


@export
class PathListArgument(CommandLineArgument):
	"""
	Represents a list of path arguments  (:class:`~pyTooling.CLIAbstraction.Argument.PathArgument`).
	"""
	# The output format can be forced to the POSIX format with :py:data:`_PosixFormat`.
	_paths: List[Path]

	def __init__(self, paths: Iterable[Path]) -> None:
		"""
		Initializes a PathListArgument instance.

		:param paths:      An iterable os Path instances.
		:raises TypeError: If iterable parameter 'paths' contains elements not of type :class:`~pathlib.Path`.
		"""
		self._paths = []
		for path in paths:
			if not isinstance(path, Path):
				raise TypeError(f"Parameter 'paths' contains elements which are not of type 'Path'.")

			self._paths.append(path)

	@property
	def Value(self) -> List[Path]:
		"""
		Get the internal list of path objects.

		:return: Reference to the internal list of path objects.
		"""
		return self._paths

	@Value.setter
	def Value(self, value: Iterable[Path]):
		"""
		Overwrite all elements in the internal list of path objects.

		.. note:: The list object is not replaced, but cleared and then reused by adding the given elements in the iterable.

		:param value:      List of path objects to set.
		:raises TypeError: If value contains elements, which are not of type :class:`~pathlib.Path`.
		"""
		self._paths.clear()
		for path in value:
			if not isinstance(path, Path):
				raise TypeError(f"Value contains elements which are not of type 'Path'.")
			self._paths.append(path)

	def AsArgument(self) -> Union[str, Iterable[str]]:
		"""
		Convert this argument instance to a string representation with proper escaping using the matching pattern based on
		the internal value.

		:return: Sequence of formatted arguments.
		"""
		return [f"{path}" for path in self._paths]

	def __str__(self) -> str:
		"""
		Return a string representation of this argument instance.

		:return: Space separated sequence of arguments formatted and each enclosed in double quotes.
		"""
		return " ".join([f"\"{value}\"" for value in self.AsArgument()])

	def __repr__(self) -> str:
		"""
		Return a string representation of this argument instance.

		:return: Comma separated sequence of arguments formatted and each enclosed in double quotes.
		"""
		return ", ".join([f"\"{value}\"" for value in self.AsArgument()])