#!/usr/bin/env python
# encoding: utf-8

"""Common functionality of the snippet parsing codes."""

from UltiSnips.position import Position
from UltiSnips.snippet.parsing._lexer import tokenize, TabStopToken
from UltiSnips.text_objects import TabStop

def tokenize_snippet_text(snippet_instance, text, indent,
        allowed_tokens_in_text, allowed_tokens_in_tabstops,
        token_to_textobject):
    """Turns 'text' into a stream of tokens and creates the text objects from
    those tokens that are mentioned in 'token_to_textobject' assuming the
    current 'indent'. The 'allowed_tokens_in_text' define which tokens will be
    recognized in 'text' while 'allowed_tokens_in_tabstops' are the tokens that
    will be recognized in TabStop placeholder text."""
    seen_ts = {}
    all_tokens = []

    def _do_parse(parent, text, allowed_tokens):
        """Recursive function that actually creates the objects."""
        tokens = list(tokenize(text, indent, parent.start, allowed_tokens))
        for token in tokens:
            all_tokens.append((parent, token))
            if isinstance(token, TabStopToken):
                ts = TabStop(parent, token)
                seen_ts[token.number] = ts
                _do_parse(ts, token.initial_text,
                        allowed_tokens_in_tabstops)
            else:
                klass = token_to_textobject.get(token.__class__, None)
                if klass is not None:
                    klass(parent, token)
    _do_parse(snippet_instance, text, allowed_tokens_in_text)
    return all_tokens, seen_ts

def finalize(all_tokens, seen_ts, snippet_instance):
    """Adds a tabstop 0 if non is in 'seen_ts' and brings the text of the
    snippet instance into Vim."""
    if 0 not in seen_ts:
        mark = all_tokens[-1][1].end # Last token is always EndOfText
        m1 = Position(mark.line, mark.col)
        TabStop(snippet_instance, 0, mark, m1)
    snippet_instance.replace_initial_text()
