import enum
import json
import os
import re
import typing as t
from collections import abc
from collections import deque
from random import choice
from random import randrange
from threading import Lock
from types import CodeType
from urllib.parse import quote_from_bytes

import markupsafe

if t.TYPE_CHECKING:
    import typing_extensions as te

F = t.TypeVar("F", bound=t.Callable[..., t.Any])


class _MissingType:
    def __repr__(self) -> str:
        return "missing"

    def __reduce__(self) -> str:
        return "missing"


missing: t.Any = _MissingType()
"""Special singleton representing missing values for the runtime."""

internal_code: t.MutableSet[CodeType] = set()

concat = "".join


def pass_context(f: F) -> F:
    """Pass the :class:`~jinja2.runtime.Context` as the first argument
    to the decorated function when called while rendering a template.

    Can be used on functions, filters, and tests.

    If only ``Context.eval_context`` is needed, use
    :func:`pass_eval_context`. If only ``Context.environment`` is
    needed, use :func:`pass_environment`.

    .. versionadded:: 3.0.0
        Replaces ``contextfunction`` and ``contextfilter``.
    """
    f.jinja_pass_arg = _PassArg.context  # type: ignore
    return f


def pass_eval_context(f: F) -> F:
    """Pass the :class:`~jinja2.nodes.EvalContext` as the first argument
    to the decorated function when called while rendering a template.
    See :ref:`eval-context`.

    Can be used on functions, filters, and tests.

    If only ``EvalContext.environment`` is needed, use
    :func:`pass_environment`.

    .. versionadded:: 3.0.0
        Replaces ``evalcontextfunction`` and ``evalcontextfilter``.
    """
    f.jinja_pass_arg = _PassArg.eval_context  # type: ignore
    return f


def pass_environment(f: F) -> F:
    """Pass the :class:`~jinja2.Environment` as the first argument to
    the decorated function when called while rendering a template.

    Can be used on functions, filters, and tests.

    .. versionadded:: 3.0.0
        Replaces ``environmentfunction`` and ``environmentfilter``.
    """
    f.jinja_pass_arg = _PassArg.environment  # type: ignore
    return f


class _PassArg(enum.Enum):
    context = enum.auto()
    eval_context = enum.auto()
    environment = enum.auto()

    @classmethod
    def from_obj(cls, obj: F) -> t.Optional["_PassArg"]:
        if hasattr(obj, "jinja_pass_arg"):
            return obj.jinja_pass_arg  # type: ignore

        return None


def internalcode(f: F) -> F:
    """Marks the function as internally used"""
    internal_code.add(f.__code__)
    return f


def is_undefined(obj: t.Any) -> bool:
    """Check if the object passed is undefined.  This does nothing more than
    performing an instance check against :class:`Undefined` but looks nicer.
    This can be used for custom filters or tests that want to react to
    undefined variables.  For example a custom default filter can look like
    this::

        def default(var, default=''):
            if is_undefined(var):
                return default
            return var
    """
    from .runtime import Undefined

    return isinstance(obj, Undefined)


def consume(iterable: t.Iterable[t.Any]) -> None:
    """Consumes an iterable without doing anything with it."""
    for _ in iterable:
        pass


def clear_caches() -> None:
    """Jinja keeps internal caches for environments and lexers.  These are
    used so that Jinja doesn't have to recreate environments and lexers all
    the time.  Normally you don't have to care about that but if you are
    measuring memory consumption you may want to clean the caches.
    """
    from .environment import get_spontaneous_environment
    from .lexer import _lexer_cache

    get_spontaneous_environment.cache_clear()
    _lexer_cache.clear()


def import_string(import_name: str, silent: bool = False) -> t.Any:
    """Imports an object based on a string.  This is useful if you want to
    use import paths as endpoints or something similar.  An import path can
    be specified either in dotted notation (``xml.sax.saxutils.escape``)
    or with a colon as object delimiter (``xml.sax.saxutils:escape``).

    If the `silent` is True the return value will be `None` if the import
    fails.

    :return: imported object
    """
    try:
        if ":" in import_name:
            module, obj = import_name.split(":", 1)
        elif "." in import_name:
            module, _, obj = import_name.rpartition(".")
        else:
            return __import__(import_name)
        return getattr(__import__(module, None, None, [obj]), obj)
    except (ImportError, AttributeError):
        if not silent:
            raise


def open_if_exists(filename: str, mode: str = "rb") -> t.Optional[t.IO[t.Any]]:
    """Returns a file descriptor for the filename if that file exists,
    otherwise ``None``.
    """
    if not os.path.isfile(filename):
        return None

    return open(filename, mode)


def object_type_repr(obj: t.Any) -> str:
    """Returns the name of the object's type.  For some recognized
    singletons the name of the object is returned instead. (For
    example for `None` and `Ellipsis`).
    """
    if obj is None:
        return "None"
    elif obj is Ellipsis:
        return "Ellipsis"

    cls = type(obj)

    if cls.__module__ == "builtins":
        return f"{cls.__name__} object"

    return f"{cls.__module__}.{cls.__name__} object"


def pformat(obj: t.Any) -> str:
    """Format an object using :func:`pprint.pformat`."""
    from pprint import pformat

    return pformat(obj)


_http_re = re.compile(
    r"""
    ^
    (
        (https?://|www\.)  # scheme or www
        (([\w%-]+\.)+)?  # subdomain
        (
            [a-z]{2,63}  # basic tld
        |
            xn--[\w%]{2,59}  # idna tld
        )
    |
        ([\w%-]{2,63}\.)+  # basic domain
        (com|net|int|edu|gov|org|info|mil)  # basic tld
    |
        (https?://)  # scheme
        (
            (([\d]{1,3})(\.[\d]{1,3}){3})  # IPv4
        |
            (\[([\da-f]{0,4}:){2}([\da-f]{0,4}:?){1,6}])  # IPv6
        )
    )
    (?::[\d]{1,5})?  # port
    (?:[/?#]\S*)?  # path, query, and fragment
    $
    """,
    re.IGNORECASE | re.VERBOSE,
)
_email_re = re.compile(r"^\S+@\w[\w.-]*\.\w+$")


def urlize(
    text: str,
    trim_url_limit: t.Optional[int] = None,
    rel: t.Optional[str] = None,
    target: t.Optional[str] = None,
    extra_schemes: t.Optional[t.Iterable[str]] = None,
) -> str:
    """Convert URLs in text into clickable links.

    This may not recognize links in some situations. Usually, a more
    comprehensive formatter, such as a Markdown library, is a better
    choice.

    Works on ``http://``, ``https://``, ``www.``, ``mailto:``, and email
    addresses. Links with trailing punctuation (periods, commas, closing
    parentheses) and leading punctuation (opening parentheses) are
    recognized excluding the punctuation. Email addresses that include
    header fields are not recognized (for example,
    ``mailto:address@example.com?cc=copy@example.com``).

    :param text: Original text containing URLs to link.
    :param trim_url_limit: Shorten displayed URL values to this length.
    :param target: Add the ``target`` attribute to links.
    :param rel: Add the ``rel`` attribute to links.
    :param extra_schemes: Recognize URLs that start with these schemes
        in addition to the default behavior.

    .. versionchanged:: 3.0
        The ``extra_schemes`` parameter was added.

    .. versionchanged:: 3.0
        Generate ``https://`` links for URLs without a scheme.

    .. versionchanged:: 3.0
        The parsing rules were updated. Recognize email addresses with
        or without the ``mailto:`` scheme. Validate IP addresses. Ignore
        parentheses and brackets in more cases.
    """
    if trim_url_limit is not None:

        def trim_url(x: str) -> str:
            if len(x) > trim_url_limit:
                return f"{x[:trim_url_limit]}..."

            return x

    else:

        def trim_url(x: str) -> str:
            return x

    words = re.split(r"(\s+)", str(markupsafe.escape(text)))
    rel_attr = f' rel="{markupsafe.escape(rel)}"' if rel else ""
    target_attr = f' target="{markupsafe.escape(target)}"' if target else ""

    for i, word in enumerate(words):
        head, middle, tail = "", word, ""
        match = re.match(r"^([(<]|<)+", middle)

        if match:
            head = match.group()
            middle = middle[match.end() :]

        # Unlike lead, which is anchored to the start of the string,
        # need to check that the string ends with any of the characters
        # before trying to match all of them, to avoid backtracking.
        if middle.endswith((")", ">", ".", ",", "\n", ">")):
            match = re.search(r"([)>.,\n]|>)+$", middle)

            if match:
                tail = match.group()
                middle = middle[: match.start()]

        # Prefer balancing parentheses in URLs instead of ignoring a
        # trailing character.
        for start_char, end_char in ("(", ")"), ("<", ">"), ("<", ">"):
            start_count = middle.count(start_char)

            if start_count <= middle.count(end_char):
                # Balanced, or lighter on the left
                continue

            # Move as many as possible from the tail to balance
            for _ in range(min(start_count, tail.count(end_char))):
                end_index = tail.index(end_char) + len(end_char)
                # Move anything in the tail before the end char too
                middle += tail[:end_index]
                tail = tail[end_index:]

        if _http_re.match(middle):
            if middle.startswith("https://") or middle.startswith("http://"):
                middle = (
                    f'{trim_url(middle)}'
                )
            else:
                middle = (
                    f''
                    f"{trim_url(middle)}"
                )

        elif middle.startswith("mailto:") and _email_re.match(middle[7:]):
            middle = f'{middle[7:]}'

        elif (
            "@" in middle
            and not middle.startswith("www.")
            # ignore values like `@a@b`
            and not middle.startswith("@")
            and ":" not in middle
            and _email_re.match(middle)
        ):
            middle = f'{middle}'

        elif extra_schemes is not None:
            for scheme in extra_schemes:
                if middle != scheme and middle.startswith(scheme):
                    middle = f'{middle}'

        words[i] = f"{head}{middle}{tail}"

    return "".join(words)


def generate_lorem_ipsum(
    n: int = 5, html: bool = True, min: int = 20, max: int = 100
) -> str:
    """Generate some lorem ipsum for the template."""
    from .constants import LOREM_IPSUM_WORDS

    words = LOREM_IPSUM_WORDS.split()
    result = []

    for _ in range(n):
        next_capitalized = True
        last_comma = last_fullstop = 0
        word = None
        last = None
        p = []

        # each paragraph contains out of 20 to 100 words.
        for idx, _ in enumerate(range(randrange(min, max))):
            while True:
                word = choice(words)
                if word != last:
                    last = word
                    break
            if next_capitalized:
                word = word.capitalize()
                next_capitalized = False
            # add commas
            if idx - randrange(3, 8) > last_comma:
                last_comma = idx
                last_fullstop += 2
                word += ","
            # add end of sentences
            if idx - randrange(10, 20) > last_fullstop:
                last_comma = last_fullstop = idx
                word += "."
                next_capitalized = True
            p.append(word)

        # ensure that the paragraph ends with a dot.
        p_str = " ".join(p)

        if p_str.endswith(","):
            p_str = p_str[:-1] + "."
        elif not p_str.endswith("."):
            p_str += "."

        result.append(p_str)

    if not html:
        return "\n\n".join(result)
    return markupsafe.Markup(
        "\n".join(f"

{markupsafe.escape(x)}

" for x in result) ) def url_quote(obj: t.Any, charset: str = "utf-8", for_qs: bool = False) -> str: """Quote a string for use in a URL using the given charset. :param obj: String or bytes to quote. Other types are converted to string then encoded to bytes using the given charset. :param charset: Encode text to bytes using this charset. :param for_qs: Quote "/" and use "+" for spaces. """ if not isinstance(obj, bytes): if not isinstance(obj, str): obj = str(obj) obj = obj.encode(charset) safe = b"" if for_qs else b"/" rv = quote_from_bytes(obj, safe) if for_qs: rv = rv.replace("%20", "+") return rv @abc.MutableMapping.register class LRUCache: """A simple LRU Cache implementation.""" # this is fast for small capacities (something below 1000) but doesn't # scale. But as long as it's only used as storage for templates this # won't do any harm. def __init__(self, capacity: int) -> None: self.capacity = capacity self._mapping: t.Dict[t.Any, t.Any] = {} self._queue: te.Deque[t.Any] = deque() self._postinit() def _postinit(self) -> None: # alias all queue methods for faster lookup self._popleft = self._queue.popleft self._pop = self._queue.pop self._remove = self._queue.remove self._wlock = Lock() self._append = self._queue.append def __getstate__(self) -> t.Mapping[str, t.Any]: return { "capacity": self.capacity, "_mapping": self._mapping, "_queue": self._queue, } def __setstate__(self, d: t.Mapping[str, t.Any]) -> None: self.__dict__.update(d) self._postinit() def __getnewargs__(self) -> t.Tuple[t.Any, ...]: return (self.capacity,) def copy(self) -> "te.Self": """Return a shallow copy of the instance.""" rv = self.__class__(self.capacity) rv._mapping.update(self._mapping) rv._queue.extend(self._queue) return rv def get(self, key: t.Any, default: t.Any = None) -> t.Any: """Return an item from the cache dict or `default`""" try: return self[key] except KeyError: return default def setdefault(self, key: t.Any, default: t.Any = None) -> t.Any: """Set `default` if the key is not in the cache otherwise leave unchanged. Return the value of this key. """ try: return self[key] except KeyError: self[key] = default return default def clear(self) -> None: """Clear the cache.""" with self._wlock: self._mapping.clear() self._queue.clear() def __contains__(self, key: t.Any) -> bool: """Check if a key exists in this cache.""" return key in self._mapping def __len__(self) -> int: """Return the current size of the cache.""" return len(self._mapping) def __repr__(self) -> str: return f"<{type(self).__name__} {self._mapping!r}>" def __getitem__(self, key: t.Any) -> t.Any: """Get an item from the cache. Moves the item up so that it has the highest priority then. Raise a `KeyError` if it does not exist. """ with self._wlock: rv = self._mapping[key] if self._queue[-1] != key: try: self._remove(key) except ValueError: # if something removed the key from the container # when we read, ignore the ValueError that we would # get otherwise. pass self._append(key) return rv def __setitem__(self, key: t.Any, value: t.Any) -> None: """Sets the value for an item. Moves the item up so that it has the highest priority then. """ with self._wlock: if key in self._mapping: self._remove(key) elif len(self._mapping) == self.capacity: del self._mapping[self._popleft()] self._append(key) self._mapping[key] = value def __delitem__(self, key: t.Any) -> None: """Remove an item from the cache dict. Raise a `KeyError` if it does not exist. """ with self._wlock: del self._mapping[key] try: self._remove(key) except ValueError: pass def items(self) -> t.Iterable[t.Tuple[t.Any, t.Any]]: """Return a list of items.""" result = [(key, self._mapping[key]) for key in list(self._queue)] result.reverse() return result def values(self) -> t.Iterable[t.Any]: """Return a list of all values.""" return [x[1] for x in self.items()] def keys(self) -> t.Iterable[t.Any]: """Return a list of all keys ordered by most recent usage.""" return list(self) def __iter__(self) -> t.Iterator[t.Any]: return reversed(tuple(self._queue)) def __reversed__(self) -> t.Iterator[t.Any]: """Iterate over the keys in the cache dict, oldest items coming first. """ return iter(tuple(self._queue)) __copy__ = copy def select_autoescape( enabled_extensions: t.Collection[str] = ("html", "htm", "xml"), disabled_extensions: t.Collection[str] = (), default_for_string: bool = True, default: bool = False, ) -> t.Callable[[t.Optional[str]], bool]: """Intelligently sets the initial value of autoescaping based on the filename of the template. This is the recommended way to configure autoescaping if you do not want to write a custom function yourself. If you want to enable it for all templates created from strings or for all templates with `.html` and `.xml` extensions:: from jinja2 import Environment, select_autoescape env = Environment(autoescape=select_autoescape( enabled_extensions=('html', 'xml'), default_for_string=True, )) Example configuration to turn it on at all times except if the template ends with `.txt`:: from jinja2 import Environment, select_autoescape env = Environment(autoescape=select_autoescape( disabled_extensions=('txt',), default_for_string=True, default=True, )) The `enabled_extensions` is an iterable of all the extensions that autoescaping should be enabled for. Likewise `disabled_extensions` is a list of all templates it should be disabled for. If a template is loaded from a string then the default from `default_for_string` is used. If nothing matches then the initial value of autoescaping is set to the value of `default`. For security reasons this function operates case insensitive. .. versionadded:: 2.9 """ enabled_patterns = tuple(f".{x.lstrip('.').lower()}" for x in enabled_extensions) disabled_patterns = tuple(f".{x.lstrip('.').lower()}" for x in disabled_extensions) def autoescape(template_name: t.Optional[str]) -> bool: if template_name is None: return default_for_string template_name = template_name.lower() if template_name.endswith(enabled_patterns): return True if template_name.endswith(disabled_patterns): return False return default return autoescape def htmlsafe_json_dumps( obj: t.Any, dumps: t.Optional[t.Callable[..., str]] = None, **kwargs: t.Any ) -> markupsafe.Markup: """Serialize an object to a string of JSON with :func:`json.dumps`, then replace HTML-unsafe characters with Unicode escapes and mark the result safe with :class:`~markupsafe.Markup`. This is available in templates as the ``|tojson`` filter. The following characters are escaped: ``<``, ``>``, ``&``, ``'``. The returned string is safe to render in HTML documents and ``