from threading import Lock from .utils import supports_terminal_sequences, TERMINAL_SEQUENCES class MultilinePrinterBase: def __init__(self, stream=None, lines=1): self.stream = stream self.maximum = lines - 1 def __enter__(self): return self def __exit__(self, *args): self.end() def print_at_line(self, text, pos): pass def end(self): pass def _add_line_number(self, text, line): if self.maximum: return f'{line + 1}: {text}' return text class QuietMultilinePrinter(MultilinePrinterBase): pass class MultilineLogger(MultilinePrinterBase): def print_at_line(self, text, pos): # stream is the logger object, not an actual stream self.stream.debug(self._add_line_number(text, pos)) class BreaklineStatusPrinter(MultilinePrinterBase): def print_at_line(self, text, pos): self.stream.write(self._add_line_number(text, pos) + '\n') class MultilinePrinter(MultilinePrinterBase): def __init__(self, stream=None, lines=1, preserve_output=True): super().__init__(stream, lines) self.preserve_output = preserve_output self._lastline = self._lastlength = 0 self._movelock = Lock() self._HAVE_FULLCAP = supports_terminal_sequences(self.stream) def lock(func): def wrapper(self, *args, **kwargs): with self._movelock: return func(self, *args, **kwargs) return wrapper def _move_cursor(self, dest): current = min(self._lastline, self.maximum) self.stream.write('\r') distance = dest - current if distance < 0: self.stream.write(TERMINAL_SEQUENCES['UP'] * -distance) elif distance > 0: self.stream.write(TERMINAL_SEQUENCES['DOWN'] * distance) self._lastline = dest @lock def print_at_line(self, text, pos): if self._HAVE_FULLCAP: self._move_cursor(pos) self.stream.write(TERMINAL_SEQUENCES['ERASE_LINE']) self.stream.write(text) return text = self._add_line_number(text, pos) textlen = len(text) if self._lastline == pos: # move cursor at the start of progress when writing to same line self.stream.write('\r') if self._lastlength > textlen: text += ' ' * (self._lastlength - textlen) self._lastlength = textlen else: # otherwise, break the line self.stream.write('\n') self._lastlength = textlen self.stream.write(text) self._lastline = pos @lock def end(self): # move cursor to the end of the last line, and write line break # so that other to_screen calls can precede if self._HAVE_FULLCAP: self._move_cursor(self.maximum) if self.preserve_output: self.stream.write('\n') return if self._HAVE_FULLCAP: self.stream.write( TERMINAL_SEQUENCES['ERASE_LINE'] + f'{TERMINAL_SEQUENCES["UP"]}{TERMINAL_SEQUENCES["ERASE_LINE"]}' * self.maximum) else: self.stream.write(' ' * self._lastlength)