# Urwid curses output wrapper.. the horror.. # Copyright (C) 2004-2011 Ian Ward # # This library is free software; you can redistribute it and/or # modify it under the terms of the GNU Lesser General Public # License as published by the Free Software Foundation; either # version 2.1 of the License, or (at your option) any later version. # # This library is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU # Lesser General Public License for more details. # # You should have received a copy of the GNU Lesser General Public # License along with this library; if not, write to the Free Software # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA # # Urwid web site: https://urwid.org/ """ Curses-based UI implementation """ from __future__ import annotations import curses import sys import typing from contextlib import suppress from urwid import util from . import escape from .common import UNPRINTABLE_TRANS_TABLE, AttrSpec, BaseScreen, RealTerminal if typing.TYPE_CHECKING: from typing_extensions import Literal from urwid import Canvas IS_WINDOWS = sys.platform == "win32" # curses.KEY_RESIZE (sometimes not defined) if IS_WINDOWS: KEY_MOUSE = 539 # under Windows key mouse is different KEY_RESIZE = 546 COLOR_CORRECTION: dict[int, int] = dict( enumerate( ( curses.COLOR_BLACK, curses.COLOR_RED, curses.COLOR_GREEN, curses.COLOR_YELLOW, curses.COLOR_BLUE, curses.COLOR_MAGENTA, curses.COLOR_CYAN, curses.COLOR_WHITE, ) ) ) def initscr(): import curses # noqa: I001 # pylint: disable=redefined-outer-name,reimported # special case for monkeypatch import _curses stdscr = _curses.initscr() for key, value in _curses.__dict__.items(): if key[:4] == "ACS_" or key in {"LINES", "COLS"}: setattr(curses, key, value) return stdscr curses.initscr = initscr else: KEY_MOUSE = 409 # curses.KEY_MOUSE KEY_RESIZE = 410 COLOR_CORRECTION = {} _curses_colours = { # pylint: disable=consider-using-namedtuple-or-dataclass # historic test/debug data "default": (-1, 0), "black": (curses.COLOR_BLACK, 0), "dark red": (curses.COLOR_RED, 0), "dark green": (curses.COLOR_GREEN, 0), "brown": (curses.COLOR_YELLOW, 0), "dark blue": (curses.COLOR_BLUE, 0), "dark magenta": (curses.COLOR_MAGENTA, 0), "dark cyan": (curses.COLOR_CYAN, 0), "light gray": (curses.COLOR_WHITE, 0), "dark gray": (curses.COLOR_BLACK, 1), "light red": (curses.COLOR_RED, 1), "light green": (curses.COLOR_GREEN, 1), "yellow": (curses.COLOR_YELLOW, 1), "light blue": (curses.COLOR_BLUE, 1), "light magenta": (curses.COLOR_MAGENTA, 1), "light cyan": (curses.COLOR_CYAN, 1), "white": (curses.COLOR_WHITE, 1), } class Screen(BaseScreen, RealTerminal): def __init__(self) -> None: super().__init__() self.curses_pairs = [(None, None)] # Can't be sure what pair 0 will default to self.palette = {} self.has_color = False self.s = None self.cursor_state = None self.prev_input_resize = 0 self.set_input_timeouts() self.last_bstate = 0 self._mouse_tracking_enabled = False self.register_palette_entry(None, "default", "default") def set_mouse_tracking(self, enable: bool = True) -> None: """ Enable mouse tracking. After calling this function get_input will include mouse click events along with keystrokes. """ enable = bool(enable) if enable == self._mouse_tracking_enabled: return if enable: curses.mousemask( 0 | curses.BUTTON1_PRESSED | curses.BUTTON1_RELEASED | curses.BUTTON2_PRESSED | curses.BUTTON2_RELEASED | curses.BUTTON3_PRESSED | curses.BUTTON3_RELEASED | curses.BUTTON4_PRESSED | curses.BUTTON4_RELEASED | curses.BUTTON1_DOUBLE_CLICKED | curses.BUTTON1_TRIPLE_CLICKED | curses.BUTTON2_DOUBLE_CLICKED | curses.BUTTON2_TRIPLE_CLICKED | curses.BUTTON3_DOUBLE_CLICKED | curses.BUTTON3_TRIPLE_CLICKED | curses.BUTTON4_DOUBLE_CLICKED | curses.BUTTON4_TRIPLE_CLICKED | curses.BUTTON_SHIFT | curses.BUTTON_ALT | curses.BUTTON_CTRL ) else: raise NotImplementedError() self._mouse_tracking_enabled = enable def _start(self) -> None: """ Initialize the screen and input mode. """ self.s = curses.initscr() self.has_color = curses.has_colors() if self.has_color: curses.start_color() if curses.COLORS < 8: # not colourful enough self.has_color = False if self.has_color: try: curses.use_default_colors() self.has_default_colors = True except curses.error: self.has_default_colors = False self._setup_colour_pairs() curses.noecho() curses.meta(True) curses.halfdelay(10) # use set_input_timeouts to adjust self.s.keypad(False) if not self._signal_keys_set: self._old_signal_keys = self.tty_signal_keys() super()._start() if IS_WINDOWS: # halfdelay() seems unnecessary and causes everything to slow down a lot. curses.nocbreak() # exits halfdelay mode # keypad(1) is needed, or we get no special keys (cursor keys, etc.) self.s.keypad(True) def _stop(self) -> None: """ Restore the screen. """ curses.echo() self._curs_set(1) with suppress(curses.error): curses.endwin() # don't block original error with curses error if self._old_signal_keys: self.tty_signal_keys(*self._old_signal_keys) super()._stop() def _setup_colour_pairs(self) -> None: """ Initialize all 63 color pairs based on the term: bg * 8 + 7 - fg So to get a color, we just need to use that term and get the right color pair number. """ if not self.has_color: return if IS_WINDOWS: self.has_default_colors = False for fg in range(8): for bg in range(8): # leave out white on black if fg == curses.COLOR_WHITE and bg == curses.COLOR_BLACK: continue curses.init_pair(bg * 8 + 7 - fg, COLOR_CORRECTION.get(fg, fg), COLOR_CORRECTION.get(bg, bg)) def _curs_set(self, x: int): if self.cursor_state in {"fixed", x}: return try: curses.curs_set(x) self.cursor_state = x except curses.error: self.cursor_state = "fixed" def _clear(self) -> None: self.s.clear() self.s.refresh() def _getch(self, wait_tenths: int | None) -> int: if wait_tenths == 0: return self._getch_nodelay() if not IS_WINDOWS: if wait_tenths is None: curses.cbreak() else: curses.halfdelay(wait_tenths) self.s.nodelay(False) return self.s.getch() def _getch_nodelay(self) -> int: self.s.nodelay(True) if not IS_WINDOWS: while True: # this call fails sometimes, but seems to work when I try again with suppress(curses.error): curses.cbreak() break return self.s.getch() def set_input_timeouts( self, max_wait: float | None = None, complete_wait: float = 0.1, resize_wait: float = 0.1, ): """ Set the get_input timeout values. All values have a granularity of 0.1s, ie. any value between 0.15 and 0.05 will be treated as 0.1 and any value less than 0.05 will be treated as 0. The maximum timeout value for this module is 25.5 seconds. max_wait -- amount of time in seconds to wait for input when there is no input pending, wait forever if None complete_wait -- amount of time in seconds to wait when get_input detects an incomplete escape sequence at the end of the available input resize_wait -- amount of time in seconds to wait for more input after receiving two screen resize requests in a row to stop urwid from consuming 100% cpu during a gradual window resize operation """ def convert_to_tenths(s): if s is None: return None return int((s + 0.05) * 10) self.max_tenths = convert_to_tenths(max_wait) self.complete_tenths = convert_to_tenths(complete_wait) self.resize_tenths = convert_to_tenths(resize_wait) @typing.overload def get_input(self, raw_keys: Literal[False]) -> list[str]: ... @typing.overload def get_input(self, raw_keys: Literal[True]) -> tuple[list[str], list[int]]: ... def get_input(self, raw_keys: bool = False) -> list[str] | tuple[list[str], list[int]]: """Return pending input as a list. raw_keys -- return raw keycodes as well as translated versions This function will immediately return all the input since the last time it was called. If there is no input pending it will wait before returning an empty list. The wait time may be configured with the set_input_timeouts function. If raw_keys is False (default) this function will return a list of keys pressed. If raw_keys is True this function will return a ( keys pressed, raw keycodes ) tuple instead. Examples of keys returned: * ASCII printable characters: " ", "a", "0", "A", "-", "/" * ASCII control characters: "tab", "enter" * Escape sequences: "up", "page up", "home", "insert", "f1" * Key combinations: "shift f1", "meta a", "ctrl b" * Window events: "window resize" When a narrow encoding is not enabled: * "Extended ASCII" characters: "\\xa1", "\\xb2", "\\xfe" When a wide encoding is enabled: * Double-byte characters: "\\xa1\\xea", "\\xb2\\xd4" When utf8 encoding is enabled: * Unicode characters: u"\\u00a5", u'\\u253c" Examples of mouse events returned: * Mouse button press: ('mouse press', 1, 15, 13), ('meta mouse press', 2, 17, 23) * Mouse button release: ('mouse release', 0, 18, 13), ('ctrl mouse release', 0, 17, 23) """ if not self._started: raise RuntimeError keys, raw = self._get_input(self.max_tenths) # Avoid pegging CPU at 100% when slowly resizing, and work # around a bug with some braindead curses implementations that # return "no key" between "window resize" commands if keys == ["window resize"] and self.prev_input_resize: for _ in range(2): new_keys, new_raw = self._get_input(self.resize_tenths) raw += new_raw if new_keys and new_keys != ["window resize"]: if "window resize" in new_keys: keys = new_keys else: keys.extend(new_keys) break if keys == ["window resize"]: self.prev_input_resize = 2 elif self.prev_input_resize == 2 and not keys: self.prev_input_resize = 1 else: self.prev_input_resize = 0 if raw_keys: return keys, raw return keys def _get_input(self, wait_tenths: int | None) -> tuple[list[str], list[int]]: # this works around a strange curses bug with window resizing # not being reported correctly with repeated calls to this # function without a doupdate call in between curses.doupdate() key = self._getch(wait_tenths) resize = False raw = [] keys = [] while key >= 0: raw.append(key) if key == KEY_RESIZE: resize = True elif key == KEY_MOUSE: keys += self._encode_mouse_event() else: keys.append(key) key = self._getch_nodelay() processed = [] try: while keys: run, keys = escape.process_keyqueue(keys, True) processed += run except escape.MoreInputRequired: key = self._getch(self.complete_tenths) while key >= 0: raw.append(key) if key == KEY_RESIZE: resize = True elif key == KEY_MOUSE: keys += self._encode_mouse_event() else: keys.append(key) key = self._getch_nodelay() while keys: run, keys = escape.process_keyqueue(keys, False) processed += run if resize: processed.append("window resize") return processed, raw def _encode_mouse_event(self) -> list[int]: # convert to escape sequence last_state = next_state = self.last_bstate (_id, x, y, _z, bstate) = curses.getmouse() mod = 0 if bstate & curses.BUTTON_SHIFT: mod |= 4 if bstate & curses.BUTTON_ALT: mod |= 8 if bstate & curses.BUTTON_CTRL: mod |= 16 result = [] def append_button(b: int) -> None: b |= mod result.extend([27, ord("["), ord("M"), b + 32, x + 33, y + 33]) if bstate & curses.BUTTON1_PRESSED and last_state & 1 == 0: append_button(0) next_state |= 1 if bstate & curses.BUTTON2_PRESSED and last_state & 2 == 0: append_button(1) next_state |= 2 if bstate & curses.BUTTON3_PRESSED and last_state & 4 == 0: append_button(2) next_state |= 4 if bstate & curses.BUTTON4_PRESSED and last_state & 8 == 0: append_button(64) next_state |= 8 if bstate & curses.BUTTON1_RELEASED and last_state & 1: append_button(0 + escape.MOUSE_RELEASE_FLAG) next_state &= ~1 if bstate & curses.BUTTON2_RELEASED and last_state & 2: append_button(1 + escape.MOUSE_RELEASE_FLAG) next_state &= ~2 if bstate & curses.BUTTON3_RELEASED and last_state & 4: append_button(2 + escape.MOUSE_RELEASE_FLAG) next_state &= ~4 if bstate & curses.BUTTON4_RELEASED and last_state & 8: append_button(64 + escape.MOUSE_RELEASE_FLAG) next_state &= ~8 if bstate & curses.BUTTON1_DOUBLE_CLICKED: append_button(0 + escape.MOUSE_MULTIPLE_CLICK_FLAG) if bstate & curses.BUTTON2_DOUBLE_CLICKED: append_button(1 + escape.MOUSE_MULTIPLE_CLICK_FLAG) if bstate & curses.BUTTON3_DOUBLE_CLICKED: append_button(2 + escape.MOUSE_MULTIPLE_CLICK_FLAG) if bstate & curses.BUTTON4_DOUBLE_CLICKED: append_button(64 + escape.MOUSE_MULTIPLE_CLICK_FLAG) if bstate & curses.BUTTON1_TRIPLE_CLICKED: append_button(0 + escape.MOUSE_MULTIPLE_CLICK_FLAG * 2) if bstate & curses.BUTTON2_TRIPLE_CLICKED: append_button(1 + escape.MOUSE_MULTIPLE_CLICK_FLAG * 2) if bstate & curses.BUTTON3_TRIPLE_CLICKED: append_button(2 + escape.MOUSE_MULTIPLE_CLICK_FLAG * 2) if bstate & curses.BUTTON4_TRIPLE_CLICKED: append_button(64 + escape.MOUSE_MULTIPLE_CLICK_FLAG * 2) self.last_bstate = next_state return result def _dbg_instr(self): # messy input string (intended for debugging) curses.echo() self.s.nodelay(0) curses.halfdelay(100) string = self.s.getstr() curses.noecho() return string def _dbg_out(self, string) -> None: # messy output function (intended for debugging) self.s.clrtoeol() self.s.addstr(string) self.s.refresh() self._curs_set(1) def _dbg_query(self, question): # messy query (intended for debugging) self._dbg_out(question) return self._dbg_instr() def _dbg_refresh(self) -> None: self.s.refresh() def get_cols_rows(self) -> tuple[int, int]: """Return the terminal dimensions (num columns, num rows).""" rows, cols = self.s.getmaxyx() return cols, rows def _setattr(self, a): if a is None: self.s.attrset(0) return if not isinstance(a, AttrSpec): p = self._palette.get(a, (AttrSpec("default", "default"),)) a = p[0] if self.has_color: if a.foreground_basic: if a.foreground_number >= 8: fg = a.foreground_number - 8 else: fg = a.foreground_number else: fg = 7 if a.background_basic: bg = a.background_number else: bg = 0 attr = curses.color_pair(bg * 8 + 7 - fg) else: attr = 0 if a.bold: attr |= curses.A_BOLD if a.standout: attr |= curses.A_STANDOUT if a.underline: attr |= curses.A_UNDERLINE if a.blink: attr |= curses.A_BLINK self.s.attrset(attr) def draw_screen(self, size: tuple[int, int], canvas: Canvas) -> None: """Paint screen with rendered canvas.""" logger = self.logger.getChild("draw_screen") if not self._started: raise RuntimeError _cols, rows = size if canvas.rows() != rows: raise ValueError("canvas size and passed size don't match") logger.debug(f"Drawing screen with size {size!r}") for y, row in enumerate(canvas.content()): try: self.s.move(y, 0) except curses.error: # terminal shrunk? # move failed so stop rendering. return first = True lasta = None for nr, (a, cs, seg) in enumerate(row): if cs != "U": seg = seg.translate(UNPRINTABLE_TRANS_TABLE) # noqa: PLW2901 if not isinstance(seg, bytes): raise TypeError(seg) if first or lasta != a: self._setattr(a) lasta = a try: if cs in {"0", "U"}: for segment in seg: self.s.addch(0x400000 + segment) else: if cs is not None: raise ValueError(f"cs not in ('0', 'U' ,'None'): {cs!r}") if not isinstance(seg, bytes): raise TypeError(seg) self.s.addstr(seg.decode(util.get_encoding())) except curses.error: # it's OK to get out of the # screen on the lower right if y != rows - 1 or nr != len(row) - 1: # perhaps screen size changed # quietly abort. return if canvas.cursor is not None: x, y = canvas.cursor self._curs_set(1) with suppress(curses.error): self.s.move(y, x) else: self._curs_set(0) self.s.move(0, 0) self.s.refresh() self.keep_cache_alive_link = canvas def clear(self) -> None: """ Force the screen to be completely repainted on the next call to draw_screen(). """ self.s.clear() class _test: def __init__(self): self.ui = Screen() self.l = sorted(_curses_colours) for c in self.l: self.ui.register_palette( [ (f"{c} on black", c, "black", "underline"), (f"{c} on dark blue", c, "dark blue", "bold"), (f"{c} on light gray", c, "light gray", "standout"), ] ) with self.ui.start(): self.run() def run(self) -> None: class FakeRender: pass r = FakeRender() text = [f" has_color = {self.ui.has_color!r}", ""] attr = [[], []] r.coords = {} r.cursor = None for c in self.l: t = "" a = [] for p in f"{c} on black", f"{c} on dark blue", f"{c} on light gray": a.append((p, 27)) t += (p + 27 * " ")[:27] text.append(t) attr.append(a) text += ["", "return values from get_input(): (q exits)", ""] attr += [[], [], []] cols, rows = self.ui.get_cols_rows() keys = None while keys != ["q"]: r.text = ([t.ljust(cols) for t in text] + [""] * rows)[:rows] r.attr = (attr + [[] for _ in range(rows)])[:rows] self.ui.draw_screen((cols, rows), r) keys, raw = self.ui.get_input(raw_keys=True) if "window resize" in keys: cols, rows = self.ui.get_cols_rows() if not keys: continue t = "" a = [] for k in keys: if isinstance(k, str): k = k.encode(util.get_encoding()) # noqa: PLW2901 t += f"'{k}' " a += [(None, 1), ("yellow on dark blue", len(k)), (None, 2)] text.append(f"{t}: {raw!r}") attr.append(a) text = text[-rows:] attr = attr[-rows:] if __name__ == "__main__": _test()