markdown_it/main.py

from contextlib import contextmanager
from typing import Any, Callable, Dict, List, Optional, Union

from . import helpers, presets  # noqa F401
from .common import utils  # noqa F401
from .token import Token
from .parser_core import ParserCore  # noqa F401
from .parser_block import ParserBlock  # noqa F401
from .parser_inline import ParserInline  # noqa F401
from .rules_core.state_core import StateCore
from .renderer import RendererHTML
from .utils import AttrDict


_PRESETS = AttrDict(
    {
        "default": presets.default.make(),
        "zero": presets.zero.make(),
        "commonmark": presets.commonmark.make(),
    }
)


class MarkdownIt:
    def __init__(
        self, config: Union[str, AttrDict] = "commonmark", renderer_cls=RendererHTML
    ):
        """Main parser class

        :param config: name of configuration to load or a pre-defined dictionary
        :param renderer_cls: the class to load as the renderer:
            ``self.renderer = renderer_cls(self)
        """
        self.inline = ParserInline()
        self.block = ParserBlock()
        self.core = ParserCore()
        self.renderer = renderer_cls(self)

        self.utils = utils
        self.helpers = helpers
        self.options = {}
        self.configure(config)

        # var LinkifyIt    = require('linkify-it')
        # self.linkify = LinkifyIt()  # TODO maybe see https://github.com/Suor/autolink

    def __repr__(self):
        return f"{self.__class__.__module__}.{self.__class__.__name__}()"

    def __getitem__(self, name):
        return {
            "inline": self.inline,
            "block": self.block,
            "core": self.core,
            "renderer": self.renderer,
        }[name]

    def set(self, options):
        """Set parser options (in the same format as in constructor).
        Probably, you will never need it, but you can change options after constructor call.

        __Note:__ To achieve the best possible performance, don't modify a
        `markdown-it` instance options on the fly. If you need multiple configurations
        it's best to create multiple instances and initialize each with separate config.
        """
        self.options = options

    def configure(self, presets: Union[str, AttrDict]):
        """Batch load of all options and component settings.
        This is an internal method, and you probably will not need it.
        But if you will - see available presets and data structure
        [here](https://github.com/markdown-it/markdown-it/tree/master/lib/presets)

        We strongly recommend to use presets instead of direct config loads.
        That will give better compatibility with next versions.
        """
        if isinstance(presets, str):
            presetName = presets
            presets = _PRESETS.get(presetName, None)
            if not presets:
                raise KeyError(
                    'Wrong `markdown-it` preset "' + presetName + '", check name'
                )
        if not presets:
            raise ValueError("Wrong `markdown-it` preset, can't be empty")
        presets = AttrDict(presets)

        if "options" in presets:
            self.set(presets.options)

        if "components" in presets:
            for name, component in presets.components.items():
                rules = component.get("rules", None)
                if rules:
                    self[name].ruler.enableOnly(rules)
                rules2 = component.get("rules2", None)
                if rules2:
                    self[name].ruler2.enableOnly(rules2)

        return self

    def get_all_rules(self) -> Dict[str, List[str]]:
        """Return the names of all active rules."""
        rules = {
            chain: self[chain].ruler.get_all_rules()
            for chain in ["core", "block", "inline"]
        }
        rules["inline2"] = self.inline.ruler2.get_all_rules()
        return rules

    def get_active_rules(self) -> Dict[str, List[str]]:
        """Return the names of all active rules."""
        rules = {
            chain: self[chain].ruler.get_active_rules()
            for chain in ["core", "block", "inline"]
        }
        rules["inline2"] = self.inline.ruler2.get_active_rules()
        return rules

    def enable(
        self, names: Union[str, List[str]], ignoreInvalid: bool = False
    ) -> "MarkdownIt":
        """Enable list or rules. (chainable)

        :param names: rule name or list of rule names to enable.
        :param ignoreInvalid: set `true` to ignore errors when rule not found.

        It will automatically find appropriate components,
        containing rules with given names. If rule not found, and `ignoreInvalid`
        not set - throws exception.

        ##### Example

        ```python
        md = MarkdownIt()..enable(['sub', 'sup']).disable('smartquotes')
        ```
        """
        result = []

        if isinstance(names, str):
            names = [names]

        for chain in ["core", "block", "inline"]:
            result.extend(self[chain].ruler.enable(names, True))
        result.extend(self.inline.ruler2.enable(names, True))

        missed = [name for name in names if name not in result]
        if missed and not ignoreInvalid:
            raise ValueError(f"MarkdownIt. Failed to enable unknown rule(s): {missed}")

        return self

    def disable(
        self, names: Union[str, List[str]], ignoreInvalid: bool = False
    ) -> "MarkdownIt":
        """The same as [[MarkdownIt.enable]], but turn specified rules off. (chainable)

        :param names: rule name or list of rule names to disable.
        :param ignoreInvalid: set `true` to ignore errors when rule not found.

        """
        result = []

        if isinstance(names, str):
            names = [names]

        for chain in ["core", "block", "inline"]:
            result.extend(self[chain].ruler.disable(names, True))
        result.extend(self.inline.ruler2.disable(names, True))

        missed = [name for name in names if name not in result]
        if missed and not ignoreInvalid:
            raise ValueError(f"MarkdownIt. Failed to disable unknown rule(s): {missed}")
        return self

    @contextmanager
    def reset_rules(self):
        """A context manager, that will reset the current enabled rules on exit."""
        chain_rules = self.get_active_rules()
        yield
        for chain, rules in chain_rules.items():
            if chain != "inline2":
                self[chain].ruler.enableOnly(rules)
        self.inline.ruler2.enableOnly(chain_rules["inline2"])

    def add_render_rule(self, name: str, function: Callable, fmt="html"):
        """Add a rule for rendering a particular Token type.

        Only applied when ``renderer.__output__ == fmt``
        """
        if self.renderer.__output__ == fmt:
            self.renderer.rules[name] = function.__get__(self.renderer)

    def use(self, plugin: Callable, *params, **options) -> "MarkdownIt":
        """Load specified plugin with given params into current parser instance. (chainable)

        It's just a sugar to call `plugin(md, params)` with curring.

        Example::

            def func(tokens, idx):
                tokens[idx].content = tokens[idx].content.replace('foo', 'bar')
            md = MarkdownIt().use(plugin, 'foo_replace', 'text', func)

        """
        plugin(self, *params, **options)
        return self

    def parse(self, src: str, env: Optional[AttrDict] = None) -> List[Token]:
        """Parse the source string to a token stream

        :param src: source string
        :param env: environment sandbox

        Parse input string and returns list of block tokens (special token type
        "inline" will contain list of inline tokens).

        `env` is used to pass data between "distributed" rules and return additional
        metadata like reference info, needed for the renderer. It also can be used to
        inject data in specific cases. Usually, you will be ok to pass `{}`,
        and then pass updated object to renderer.
        """
        env = AttrDict() if env is None else env
        if not isinstance(env, AttrDict):
            raise TypeError(f"Input data should be an AttrDict, not {type(env)}")
        if not isinstance(src, str):
            raise TypeError(f"Input data should be a string, not {type(src)}")
        state = StateCore(src, self, env)
        self.core.process(state)
        return state.tokens

    def render(self, src: str, env: Optional[AttrDict] = None) -> Any:
        """Render markdown string into html. It does all magic for you :).

        :param src: source string
        :param env: environment sandbox
        :returns: The output of the loaded renderer

        `env` can be used to inject additional metadata (`{}` by default).
        But you will not need it with high probability. See also comment
        in [[MarkdownIt.parse]].
        """
        if env is None:
            env = AttrDict()
        return self.renderer.render(self.parse(src, env), self.options, env)

    def parseInline(self, src: str, env: Optional[AttrDict] = None) -> List[Token]:
        """The same as [[MarkdownIt.parse]] but skip all block rules.

        :param src: source string
        :param env: environment sandbox

        It returns the
        block tokens list with the single `inline` element, containing parsed inline
        tokens in `children` property. Also updates `env` object.
        """
        env = AttrDict() if env is None else env
        if not isinstance(env, AttrDict):
            raise TypeError(f"Input data should be an AttrDict, not {type(env)}")
        if not isinstance(src, str):
            raise TypeError(f"Input data should be a string, not {type(src)}")
        state = StateCore(src, self, env)
        state.inlineMode = True
        self.core.process(state)
        return state.tokens

    def renderInline(self, src: str, env: Optional[AttrDict] = None) -> Any:
        """Similar to [[MarkdownIt.render]] but for single paragraph content.

        :param src: source string
        :param env: environment sandbox

        Similar to [[MarkdownIt.render]] but for single paragraph content. Result
        will NOT be wrapped into `<p>` tags.
        """
        env = AttrDict() if env is None else env
        return self.renderer.render(self.parseInline(src, env), self.options, env)