RasaHQ/rasa_core

from pygments.lexer import RegexLexer, bygroups, using, default, include
from pygments.lexers.data import JsonLexer
from pygments.token import *


class StoryLexer(RegexLexer):
    """Lexer for the Rasa Core story file format.

    Used for syntax highlighting of story snippets in the docs."""

    name = 'Story'
    aliases = ['story']
    filenames = ['*.md']

    tokens = {
        'comment': [
            (r'(\s*<!--)((?:.*?\n?)*)(-->)',
             bygroups(Keyword, Comment.MultiLine, Keyword)),
        ],
        'root': [
            include("comment"),
            (r'\s*-\s*(slot)', Token.Operator, ("event", "event_rx")),
            (r'\s*-\s*(restart)', Token.Operator, ("event", "event_rx")),
            (r'\s*-\s*(rewind)', Token.Operator, ("event", "event_rx")),
            (r'\s*-\s*(reset_slots)', Token.Operator, ("event", "event_rx")),
            (r'\s*-\s*(reminder)', Token.Operator, ("event", "event_rx")),
            (r'\s*-\s*(undo)', Token.Operator, ("event", "event_rx")),
            (r'\s*-\s*(export)', Token.Operator, ("event", "event_rx")),
            (r'\s*-\s*(pause)', Token.Operator, ("event", "event_rx")),
            (r'\s*-\s*(resume)', Token.Operator, ("event", "event_rx")),
            (r'\s*-\s*(utter_[^\s]*)', Token.Text, ("event", "event_rx")),
            (r'(\s*-(?:\s*)(?:.*?))(\s*)(?:(?:(<!--)'
             r'((?:.*?\n?)*)(-->))|(\n|$))',
             bygroups(Text, Text, Keyword, Comment.MultiLine,
                      Keyword, Text)),
            (r'\s*\>\s*[^\s]*', Name.Constant),
            (r'(#+(?:\s*)(?:.*?))(\s*)(?:(?:(<!--)((?:.*?\n?)*)(-->))|(\n|$))',
             bygroups(Generic.Heading, Text, Keyword, Comment.MultiLine,
                      Keyword, Text)),
            (r'\s*\*\s*', Name.Variable.Magic, ("intent", "intent_rx")),
            (r'.*\n', Text),
        ],
        'event': [
            include("comment"),
            (r'\s*(\n|$)', Text, '#pop')
        ],
        'event_rx': [
            (r'({.*?})?',
             bygroups(using(JsonLexer)), "#pop"),
        ],
        'intent': [
            (r'\s*OR\s*', Keyword, "intent_rx"),
            include("comment"),
            (r'\s*(?:\n|$)', Text, '#pop'),
            default('#pop')
        ],
        'intent_rx': [
            (r'["\'].*["\']', Name.Variable.Magic, "#pop"),
            (r'([^\s\{]*\s*)({.*?})?',
             bygroups(Name.Variable.Magic, using(JsonLexer)), "#pop"),
            (r'\s*(\n|$)', Text, '#pop:2')
        ]
    }