import re from enum import Enum from .common import PostProcessor class MetadataParserPP(PostProcessor): class Actions(Enum): INTERPRET = 'interpretter' REPLACE = 'replacer' def __init__(self, downloader, actions): PostProcessor.__init__(self, downloader) self._actions = [] for f in actions: action = f[0] assert isinstance(action, self.Actions) self._actions.append(getattr(self, action._value_)(*f[1:])) @classmethod def validate_action(cls, action, *data): ''' Each action can be: (Actions.INTERPRET, from, to) OR (Actions.REPLACE, field, search, replace) ''' if not isinstance(action, cls.Actions): raise ValueError(f'{action!r} is not a valid action') getattr(cls, action._value_)(cls, *data) @staticmethod def field_to_template(tmpl): if re.match(r'[a-zA-Z_]+$', tmpl): return f'%({tmpl})s' return tmpl @staticmethod def format_to_regex(fmt): r""" Converts a string like '%(title)s - %(artist)s' to a regex like '(?P<title>.+)\ \-\ (?P<artist>.+)' """ if not re.search(r'%\(\w+\)s', fmt): return fmt lastpos = 0 regex = '' # replace %(..)s with regex group and escape other string parts for match in re.finditer(r'%\((\w+)\)s', fmt): regex += re.escape(fmt[lastpos:match.start()]) regex += rf'(?P<{match.group(1)}>.+)' lastpos = match.end() if lastpos < len(fmt): regex += re.escape(fmt[lastpos:]) return regex def run(self, info): for f in self._actions: f(info) return [], info def interpretter(self, inp, out): def f(info): data_to_parse = self._downloader.evaluate_outtmpl(template, info) self.write_debug(f'Searching for {out_re.pattern!r} in {template!r}') match = out_re.search(data_to_parse) if match is None: self.report_warning(f'Could not interpret {inp!r} as {out!r}') return for attribute, value in match.groupdict().items(): info[attribute] = value self.to_screen('Parsed %s from %r: %r' % (attribute, template, value if value is not None else 'NA')) template = self.field_to_template(inp) out_re = re.compile(self.format_to_regex(out)) return f def replacer(self, field, search, replace): def f(info): val = info.get(field) if val is None: self.report_warning(f'Video does not have a {field}') return elif not isinstance(val, str): self.report_warning(f'Cannot replace in field {field} since it is a {type(val).__name__}') return self.write_debug(f'Replacing all {search!r} in {field} with {replace!r}') info[field], n = search_re.subn(replace, val) if n: self.to_screen(f'Changed {field} to: {info[field]}') else: self.to_screen(f'Did not find {search!r} in {field}') search_re = re.compile(search) return f class MetadataFromFieldPP(MetadataParserPP): @classmethod def to_action(cls, f): match = re.match(r'(?P<in>.*?)(?<!\\):(?P<out>.+)$', f) if match is None: raise ValueError(f'it should be FROM:TO, not {f!r}') return ( cls.Actions.INTERPRET, match.group('in').replace('\\:', ':'), match.group('out')) def __init__(self, downloader, formats): MetadataParserPP.__init__(self, downloader, [self.to_action(f) for f in formats]) class MetadataFromTitlePP(MetadataParserPP): # for backward compatibility def __init__(self, downloader, titleformat): MetadataParserPP.__init__(self, downloader, [(self.Actions.INTERPRET, 'title', titleformat)])