from __future__ import annotations from collections import defaultdict from typing import TYPE_CHECKING, Callable from prompt_toolkit.cache import FastDictCache from prompt_toolkit.data_structures import Point from prompt_toolkit.utils import get_cwidth if TYPE_CHECKING: from .containers import Window __all__ = [ "Screen", "Char", ] class Char: """ Represent a single character in a :class:`.Screen`. This should be considered immutable. :param char: A single character (can be a double-width character). :param style: A style string. (Can contain classnames.) """ __slots__ = ("char", "style", "width") # If we end up having one of these special control sequences in the input string, # we should display them as follows: # Usually this happens after a "quoted insert". display_mappings: dict[str, str] = { "\x00": "^@", # Control space "\x01": "^A", "\x02": "^B", "\x03": "^C", "\x04": "^D", "\x05": "^E", "\x06": "^F", "\x07": "^G", "\x08": "^H", "\x09": "^I", "\x0a": "^J", "\x0b": "^K", "\x0c": "^L", "\x0d": "^M", "\x0e": "^N", "\x0f": "^O", "\x10": "^P", "\x11": "^Q", "\x12": "^R", "\x13": "^S", "\x14": "^T", "\x15": "^U", "\x16": "^V", "\x17": "^W", "\x18": "^X", "\x19": "^Y", "\x1a": "^Z", "\x1b": "^[", # Escape "\x1c": "^\\", "\x1d": "^]", "\x1e": "^^", "\x1f": "^_", "\x7f": "^?", # ASCII Delete (backspace). # Special characters. All visualized like Vim does. "\x80": "<80>", "\x81": "<81>", "\x82": "<82>", "\x83": "<83>", "\x84": "<84>", "\x85": "<85>", "\x86": "<86>", "\x87": "<87>", "\x88": "<88>", "\x89": "<89>", "\x8a": "<8a>", "\x8b": "<8b>", "\x8c": "<8c>", "\x8d": "<8d>", "\x8e": "<8e>", "\x8f": "<8f>", "\x90": "<90>", "\x91": "<91>", "\x92": "<92>", "\x93": "<93>", "\x94": "<94>", "\x95": "<95>", "\x96": "<96>", "\x97": "<97>", "\x98": "<98>", "\x99": "<99>", "\x9a": "<9a>", "\x9b": "<9b>", "\x9c": "<9c>", "\x9d": "<9d>", "\x9e": "<9e>", "\x9f": "<9f>", # For the non-breaking space: visualize like Emacs does by default. # (Print a space, but attach the 'nbsp' class that applies the # underline style.) "\xa0": " ", } def __init__(self, char: str = " ", style: str = "") -> None: # If this character has to be displayed otherwise, take that one. if char in self.display_mappings: if char == "\xa0": style += " class:nbsp " # Will be underlined. else: style += " class:control-character " char = self.display_mappings[char] self.char = char self.style = style # Calculate width. (We always need this, so better to store it directly # as a member for performance.) self.width = get_cwidth(char) # In theory, `other` can be any type of object, but because of performance # we don't want to do an `isinstance` check every time. We assume "other" # is always a "Char". def _equal(self, other: Char) -> bool: return self.char == other.char and self.style == other.style def _not_equal(self, other: Char) -> bool: # Not equal: We don't do `not char.__eq__` here, because of the # performance of calling yet another function. return self.char != other.char or self.style != other.style if not TYPE_CHECKING: __eq__ = _equal __ne__ = _not_equal def __repr__(self) -> str: return f"{self.__class__.__name__}({self.char!r}, {self.style!r})" _CHAR_CACHE: FastDictCache[tuple[str, str], Char] = FastDictCache( Char, size=1000 * 1000 ) Transparent = "[transparent]" class Screen: """ Two dimensional buffer of :class:`.Char` instances. """ def __init__( self, default_char: Char | None = None, initial_width: int = 0, initial_height: int = 0, ) -> None: if default_char is None: default_char2 = _CHAR_CACHE[" ", Transparent] else: default_char2 = default_char self.data_buffer: defaultdict[int, defaultdict[int, Char]] = defaultdict( lambda: defaultdict(lambda: default_char2) ) #: Escape sequences to be injected. self.zero_width_escapes: defaultdict[int, defaultdict[int, str]] = defaultdict( lambda: defaultdict(lambda: "") ) #: Position of the cursor. self.cursor_positions: dict[ Window, Point ] = {} # Map `Window` objects to `Point` objects. #: Visibility of the cursor. self.show_cursor = True #: (Optional) Where to position the menu. E.g. at the start of a completion. #: (We can't use the cursor position, because we don't want the #: completion menu to change its position when we browse through all the #: completions.) self.menu_positions: dict[ Window, Point ] = {} # Map `Window` objects to `Point` objects. #: Currently used width/height of the screen. This will increase when #: data is written to the screen. self.width = initial_width or 0 self.height = initial_height or 0 # Windows that have been drawn. (Each `Window` class will add itself to # this list.) self.visible_windows_to_write_positions: dict[Window, WritePosition] = {} # List of (z_index, draw_func) self._draw_float_functions: list[tuple[int, Callable[[], None]]] = [] @property def visible_windows(self) -> list[Window]: return list(self.visible_windows_to_write_positions.keys()) def set_cursor_position(self, window: Window, position: Point) -> None: """ Set the cursor position for a given window. """ self.cursor_positions[window] = position def set_menu_position(self, window: Window, position: Point) -> None: """ Set the cursor position for a given window. """ self.menu_positions[window] = position def get_cursor_position(self, window: Window) -> Point: """ Get the cursor position for a given window. Returns a `Point`. """ try: return self.cursor_positions[window] except KeyError: return Point(x=0, y=0) def get_menu_position(self, window: Window) -> Point: """ Get the menu position for a given window. (This falls back to the cursor position if no menu position was set.) """ try: return self.menu_positions[window] except KeyError: try: return self.cursor_positions[window] except KeyError: return Point(x=0, y=0) def draw_with_z_index(self, z_index: int, draw_func: Callable[[], None]) -> None: """ Add a draw-function for a `Window` which has a >= 0 z_index. This will be postponed until `draw_all_floats` is called. """ self._draw_float_functions.append((z_index, draw_func)) def draw_all_floats(self) -> None: """ Draw all float functions in order of z-index. """ # We keep looping because some draw functions could add new functions # to this list. See `FloatContainer`. while self._draw_float_functions: # Sort the floats that we have so far by z_index. functions = sorted(self._draw_float_functions, key=lambda item: item[0]) # Draw only one at a time, then sort everything again. Now floats # might have been added. self._draw_float_functions = functions[1:] functions[0][1]() def append_style_to_content(self, style_str: str) -> None: """ For all the characters in the screen. Set the style string to the given `style_str`. """ b = self.data_buffer char_cache = _CHAR_CACHE append_style = " " + style_str for y, row in b.items(): for x, char in row.items(): row[x] = char_cache[char.char, char.style + append_style] def fill_area( self, write_position: WritePosition, style: str = "", after: bool = False ) -> None: """ Fill the content of this area, using the given `style`. The style is prepended before whatever was here before. """ if not style.strip(): return xmin = write_position.xpos xmax = write_position.xpos + write_position.width char_cache = _CHAR_CACHE data_buffer = self.data_buffer if after: append_style = " " + style prepend_style = "" else: append_style = "" prepend_style = style + " " for y in range( write_position.ypos, write_position.ypos + write_position.height ): row = data_buffer[y] for x in range(xmin, xmax): cell = row[x] row[x] = char_cache[ cell.char, prepend_style + cell.style + append_style ] class WritePosition: def __init__(self, xpos: int, ypos: int, width: int, height: int) -> None: assert height >= 0 assert width >= 0 # xpos and ypos can be negative. (A float can be partially visible.) self.xpos = xpos self.ypos = ypos self.width = width self.height = height def __repr__(self) -> str: return "{}(x={!r}, y={!r}, width={!r}, height={!r})".format( self.__class__.__name__, self.xpos, self.ypos, self.width, self.height, )