# Source code for mopidy.config.types

    import logging
    import re
    import socket

    from mopidy.config import validators
    from mopidy.internal import log, path

    def decode(value):
        if isinstance(value, bytes):
            value = value.decode(errors="surrogateescape")

        for char in ("\\", "\n", "\t"):
            value = value.replace(
                char.encode(encoding="unicode-escape").decode(), char
            )

        return value

    def encode(value):
        if isinstance(value, bytes):
            value = value.decode(errors="surrogateescape")

        for char in ("\\", "\n", "\t"):
            value = value.replace(
                char, char.encode(encoding="unicode-escape").decode()
            )

        return value

    class DeprecatedValue:
        pass

    class ConfigValue:
        """Represents a config key's value and how to handle it.

        Normally you will only be interacting with sub-classes for config values
        that encode either deserialization behavior and/or validation.

        Each config value should be used for the following actions:

        1. Deserializing from a raw string and validating, raising ValueError on
           failure.
        2. Serializing a value back to a string that can be stored in a config.
        3. Formatting a value to a printable form (useful for masking secrets).

        :class:`None` values should not be deserialized, serialized or formatted,
        the code interacting with the config should simply skip None config values.
        """

        def deserialize(self, value):
            """Cast raw string to appropriate type."""
            return decode(value)

        def serialize(self, value, display=False):
            """Convert value back to string for saving."""
            if value is None:
                return ""
            return str(value)

    class Deprecated(ConfigValue):
        """Deprecated value.

        Used for ignoring old config values that are no longer in use, but should
        not cause the config parser to crash.
        """

        def deserialize(self, value):
            return DeprecatedValue()

        def serialize(self, value, display=False):
            return DeprecatedValue()

    class String(ConfigValue):
        """String value.

        Is decoded as utf-8 and \\n \\t escapes should work and be preserved.
        """

        def __init__(self, optional=False, choices=None):
            self._required = not optional
            self._choices = choices

        def deserialize(self, value):
            value = decode(value).strip()
            validators.validate_required(value, self._required)
            if not value:
                return None
            validators.validate_choice(value, self._choices)
            return value

        def serialize(self, value, display=False):
            if value is None:
                return ""
            return encode(value)

    class Secret(String):
        """Secret string value.

        Is decoded as utf-8 and \\n \\t escapes should work and be preserved.

        Should be used for passwords, auth tokens etc. Will mask value when being
        displayed.
        """

        def __init__(self, optional=False, choices=None):
            self._required = not optional
            self._choices = None  # Choices doesn't make sense for secrets

        def serialize(self, value, display=False):
            if value is not None and display:
                return "********"
            return super().serialize(value, display)

    class Integer(ConfigValue):
        """Integer value."""

        def __init__(
            self, minimum=None, maximum=None, choices=None, optional=False
        ):
            self._required = not optional
            self._minimum = minimum
            self._maximum = maximum
            self._choices = choices

        def deserialize(self, value):
            value = decode(value)
            validators.validate_required(value, self._required)
            if not value:
                return None
            value = int(value)
            validators.validate_choice(value, self._choices)
            validators.validate_minimum(value, self._minimum)
            validators.validate_maximum(value, self._maximum)
            return value

    class Boolean(ConfigValue):
        """Boolean value.

        Accepts ``1``, ``yes``, ``true``, and ``on`` with any casing as
        :class:`True`.

        Accepts ``0``, ``no``, ``false``, and ``off`` with any casing as
        :class:`False`.
        """

        true_values = ("1", "yes", "true", "on")
        false_values = ("0", "no", "false", "off")

        def __init__(self, optional=False):
            self._required = not optional

        def deserialize(self, value):
            value = decode(value)
            validators.validate_required(value, self._required)
            if not value:
                return None
            if value.lower() in self.true_values:
                return True
            elif value.lower() in self.false_values:
                return False
            raise ValueError(f"invalid value for boolean: {value!r}")

        def serialize(self, value, display=False):
            if value is True:
                return "true"
            elif value in (False, None):
                return "false"
            else:
                raise ValueError(f"{value!r} is not a boolean")

    class List(ConfigValue):
        """List value.

        Supports elements split by commas or newlines. Newlines take presedence and
        empty list items will be filtered out.
        """

        def __init__(self, optional=False):
            self._required = not optional

        def deserialize(self, value):
            value = decode(value)
            if "\n" in value:
                values = re.split(r"\s*\n\s*", value)
            else:
                values = re.split(r"\s*,\s*", value)
            values = tuple(v.strip() for v in values if v.strip())
            validators.validate_required(values, self._required)
            return tuple(values)

        def serialize(self, value, display=False):
            if not value:
                return ""
            return "\n  " + "\n  ".join(encode(v) for v in value if v)

    class LogColor(ConfigValue):
        def deserialize(self, value):
            value = decode(value)
            validators.validate_choice(value.lower(), log.COLORS)
            return value.lower()

        def serialize(self, value, display=False):
            if value.lower() in log.COLORS:
                return encode(value.lower())
            return ""

    class LogLevel(ConfigValue):
        """Log level value.

        Expects one of ``critical``, ``error``, ``warning``, ``info``, ``debug``,
        ``trace``, or ``all``, with any casing.
        """

        levels = {
            "critical": logging.CRITICAL,
            "error": logging.ERROR,
            "warning": logging.WARNING,
            "info": logging.INFO,
            "debug": logging.DEBUG,
            "trace": log.TRACE_LOG_LEVEL,
            "all": logging.NOTSET,
        }

        def deserialize(self, value):
            value = decode(value)
            validators.validate_choice(value.lower(), self.levels.keys())
            return self.levels.get(value.lower())

        def serialize(self, value, display=False):
            lookup = {v: k for k, v in self.levels.items()}
            if value in lookup:
                return encode(lookup[value])
            return ""

    class Hostname(ConfigValue):
        """Network hostname value."""

        def __init__(self, optional=False):
            self._required = not optional

        def deserialize(self, value, display=False):
            value = decode(value).strip()
            validators.validate_required(value, self._required)
            if not value:
                return None

            socket_path = path.get_unix_socket_path(value)
            if socket_path is not None:
                path_str = Path(not self._required).deserialize(socket_path)
                return f"unix:{path_str}"

            try:
                socket.getaddrinfo(value, None)
            except OSError:
                raise ValueError("must be a resolveable hostname or valid IP")

            return value

    class Port(Integer):
        """Network port value.

        Expects integer in the range 0-65535, zero tells the kernel to simply
        allocate a port for us.
        """

        def __init__(self, choices=None, optional=False):
            super().__init__(
                minimum=0, maximum=2 ** 16 - 1, choices=choices, optional=optional
            )

    class _ExpandedPath(str):
        def __new__(cls, original, expanded):
            return super().__new__(cls, expanded)

        def __init__(self, original, expanded):
            self.original = original

    class Path(ConfigValue):
        """File system path.

        The following expansions of the path will be done:

        - ``~`` to the current user's home directory
        - ``$XDG_CACHE_DIR`` according to the XDG spec
        - ``$XDG_CONFIG_DIR`` according to the XDG spec
        - ``$XDG_DATA_DIR`` according to the XDG spec
        - ``$XDG_MUSIC_DIR`` according to the XDG spec
        """

        def __init__(self, optional=False):
            self._required = not optional

        def deserialize(self, value):
            value = decode(value).strip()
            expanded = path.expand_path(value)
            validators.validate_required(value, self._required)
            validators.validate_required(expanded, self._required)
            if not value or expanded is None:
                return None
            return _ExpandedPath(value, expanded)

        def serialize(self, value, display=False):
            if isinstance(value, _ExpandedPath):
                value = value.original
            if isinstance(value, bytes):
                value = value.decode(errors="surrogateescape")
            return value