"""
    pygments.lexers.snobol
    ~~~~~~~~~~~~~~~~~~~~~~

    Lexers for the SNOBOL language.

    :copyright: Copyright 2006-2023 by the Pygments team, see AUTHORS.
    :license: BSD, see LICENSE for details.
"""

from pygments.lexer import RegexLexer, bygroups
from pygments.token import Text, Comment, Operator, Keyword, Name, String, Number, Punctuation

__all__ = ["SnobolLexer"]


class SnobolLexer(RegexLexer):
    """
    Lexer for the SNOBOL4 programming language.

    Recognizes the common ASCII equivalents of the original SNOBOL4 operators.
    Does not require spaces around binary operators.

    .. versionadded:: 1.5
    """

    name = "Snobol"
    aliases = ["snobol"]
    filenames = ["*.snobol"]
    mimetypes = ["text/x-snobol"]

    tokens = {
        # root state, start of line
        # comments, continuation lines, and directives start in column 1
        # as do labels
        "root": [
            (r"\*.*\n", Comment),
            (r"[+.] ", Punctuation, "statement"),
            (r"-.*\n", Comment),
            (r"END\s*\n", Name.Label, "heredoc"),
            (r"[A-Za-z$][\w$]*", Name.Label, "statement"),
            (r"\s+", Text, "statement"),
        ],
        # statement state, line after continuation or label
        "statement": [
            (r"\s*\n", Text, "#pop"),
            (r"\s+", Text),
            (
                r"(?<=[^\w.])(LT|LE|EQ|NE|GE|GT|INTEGER|IDENT|DIFFER|LGT|SIZE|"
                r"REPLACE|TRIM|DUPL|REMDR|DATE|TIME|EVAL|APPLY|OPSYN|LOAD|UNLOAD|"
                r"LEN|SPAN|BREAK|ANY|NOTANY|TAB|RTAB|REM|POS|RPOS|FAIL|FENCE|"
                r"ABORT|ARB|ARBNO|BAL|SUCCEED|INPUT|OUTPUT|TERMINAL)(?=[^\w.])",
                Name.Builtin,
            ),
            (r"[A-Za-z][\w.]*", Name),
            # ASCII equivalents of original operators
            # | for the EBCDIC equivalent, ! likewise
            # \ for EBCDIC negation
            (r"\*\*|[?$.!%*/#+\-@|&\\=]", Operator),
            (r'"[^"]*"', String),
            (r"'[^']*'", String),
            # Accept SPITBOL syntax for real numbers
            # as well as Macro SNOBOL4
            (r"[0-9]+(?=[^.EeDd])", Number.Integer),
            (r"[0-9]+(\.[0-9]*)?([EDed][-+]?[0-9]+)?", Number.Float),
            # Goto
            (r":", Punctuation, "goto"),
            (r"[()<>,;]", Punctuation),
        ],
        # Goto block
        "goto": [
            (r"\s*\n", Text, "#pop:2"),
            (r"\s+", Text),
            (r"F|S", Keyword),
            (r"(\()([A-Za-z][\w.]*)(\))", bygroups(Punctuation, Name.Label, Punctuation)),
        ],
        # everything after the END statement is basically one
        # big heredoc.
        "heredoc": [(r".*\n", String.Heredoc)],
    }
