Source code for lighty.templates.tag

"""Package provides template tags manager and base tags list
"""
VARIABLE = 0
STRING = 1
NUMBER = 2


def parse_token(token):
    tokens = []
    token_types = []
    delim = None
    sentence = None
    for word in [word for word in token.split(' ') if len(word) > 0]:
        if delim is None:
            idx = word.find('"')
            if idx < 0:
                idx = word.find("'")
            if idx >= 0:
                delim = word[idx]
                if idx > 0:
                    token_types.append(STRING)
                    tokens.append(word[0:idx])
                word = word[idx + 1:]
                if delim in word:
                    parts = word.split(delim)
                    tokens.append(parts[0])
                    token_types.append(STRING)
                    if len(parts) > 1 and len(parts[1]) > 0:
                        token_types.append(VARIABLE)
                        tokens.append(parts[1])
                    delim = None
                else:
                    sentence = [word]
            else:
                tokens.append(word)
                try:
                    float(word)
                except:
                    token_types.append(VARIABLE)
                else:
                    token_types.append(NUMBER)
        else:
            if delim in word:
                parts = word.split(delim)
                sentence.append(parts[0])
                tokens.append(" ".join(sentence))
                token_types.append(STRING)
                if len(parts) > 1 and len(parts[1]) > 0:
                    token_types.append(STRING)
                    tokens.append(parts[1])
                delim = None
            else:
                sentence.append(word)
    return tokens, token_types


class TagManager(object):
    """Class used for tags manipulation
    """

    def __init__(self):
        """Create new tag managet instance
        """
        super(TagManager, self).__init__()
        self.tags = {}

    def register(self, name, tag, is_block_tag=False, context_required=False,
                 template_required=False, loader_required=False,
                 is_lazy_tag=True):
        """Register new tag
        """
        self.tags[name] = (
            tag,
            is_block_tag,
            context_required,
            template_required,
            loader_required,
            is_lazy_tag
        )

    def is_tag_exists(self, name):
        """Check is tag exists
        """
        if name not in self.tags:
            raise Exception("Tag '%s' is not registered" % name)
        return self.tags[name]

    def is_block_tag(self, name):
        """Check is tag with specified name is block tag
        """
        return self.is_tag_exists(name)[1]

    def is_lazy_tag(self, name):
        """Check is tag with specified name is lazy tag
        Lazy tag means that it would be executed on template execution. But
        some tags required to be executed on template parsing time.
        """
        return self.is_tag_exists(name)[5]

    def execute(self, name, token, context, block, template, loader):
        """Execute tag
        """
        tag = self.is_tag_exists(name)
        args = {'token': token}
        if tag[1]:
            args['block'] = block
        if tag[2]:
            args['context'] = context
        if tag[3]:
            args['template'] = template
        if tag[4]:
            args['loader'] = loader
        return tag[0](**args)

tag_manager = TagManager()