path: root/ranger/gui/ui.py

# This file is part of ranger, the console file manager.
# License: GNU GPL version 3, see the file "AUTHORS" for details.

from __future__ import (absolute_import, division, print_function)

import os
import sys
import threading
import curses
from subprocess import CalledProcessError

from ranger.ext.keybinding_parser import KeyBuffer, KeyMaps, ALT_KEY
from ranger.ext.lazy_property import lazy_property
from ranger.ext.signals import Signal
from ranger.ext.spawn import check_output

from .displayable import DisplayableContainer
from .mouse_event import MouseEvent


MOUSEMASK = curses.ALL_MOUSE_EVENTS | curses.REPORT_MOUSE_POSITION

# This escape is not available with a capname from terminfo unlike
# tsl (to_status_line), so it's hardcoded here. It's used just like tsl,
# but it sets the icon title (WM_ICON_NAME) instead of the window title
# (WM_NAME).
ESCAPE_ICON_TITLE = '\033]1;'

_ASCII = ''.join(chr(c) for c in range(32, 127))


def ascii_only(string):
    return ''.join(c if c in _ASCII else '?' for c in string)


def _setup_mouse(signal):
    if signal['value']:
        curses.mousemask(MOUSEMASK)
        curses.mouseinterval(0)

        # This line solves this problem:
        # If a mouse click triggers an action that disables curses and
        # starts curses again, (e.g. running a ## file by clicking on its
        # preview) and the next key is another mouse click, the bstate of this
        # mouse event will be invalid.  (atm, invalid bstates are recognized
        # as scroll-down, so this avoids an errorneous scroll-down action)
        curses.ungetmouse(0, 0, 0, 0, 0)
    else:
        curses.mousemask(0)


class UI(  # pylint: disable=too-many-instance-attributes,too-many-public-methods
        DisplayableContainer):
    ALLOWED_VIEWMODES = 'miller', 'multipane'

    is_set_up = False
    load_mode = False
    is_on = False
    termsize = None

    def __init__(self, env=None, fm=None):  # pylint: disable=super-init-not-called
        self.keybuffer = KeyBuffer()
        self.keymaps = KeyMaps(self.keybuffer)
        self.redrawlock = threading.Event()
        self.redrawlock.set()

        self.titlebar = None
        self._viewmode = None
        self.taskview = None
        self.status = None
        self.console = None
        self.pager = None
        self.multiplexer = None
        self._draw_title = None
        self._tmux_automatic_rename = None
        self._tmux_allow_rename = None
        self._screen_title = None
        self.browser = None

        if fm is not None:
            self.fm = fm

    def setup_curses(self):
        os.environ['ESCDELAY'] = '25'   # don't know a cleaner way
        try:
            self.win = curses.initscr()
        except curses.error as ex:
            if ex.args[0] == "setupterm: could not find terminal":
                os.environ['TERM'] = 'linux'
                self.win = curses.initscr()
        self.keymaps.use_keymap('browser')
        DisplayableContainer.__init__(self, None)

    def initialize(self):
        """initialize curses, then call setup (at the first time) and resize."""
        self.win.leaveok(0)
        self.win.keypad(1)
        self.load_mode = False
        curses.cbreak()
        curses.noecho()
        curses.halfdelay(20)
        try:
            curses.curs_set(int(bool(self.settings.show_cursor)))
        except curses.error:
            pass
        curses.start_color()
        try:
            curses.use_default_colors()
        except curses.error:
            pass

        self.settings.signal_bind('setopt.mouse_enabled', _setup_mouse)
        self.settings.signal_bind('setopt.freeze_files', self.redraw_statusbar)
        _setup_mouse(dict(value=self.settings.mouse_enabled))

        if not self.is_set_up:
            self.is_set_up = True
            self.setup()
            self.win.addstr("loading...")
            self.win.refresh()
            self._draw_title = curses.tigetflag('hs')  # has_status_line

            if 'TMUX' in os.environ:
                self.multiplexer = 'TMUX'
            elif os.environ['TERM'] == 'screen':
                self.multiplexer = 'screen'

            self.handle_multiplexer(self.multiplexer)

        self.update_size()
        self.is_on = True

        if 'vcsthread' in self.__dict__:
            self.vcsthread.unpause()

    def suspend(self):
        """Turn off curses"""
        if 'vcsthread' in self.__dict__:
            self.vcsthread.pause()
            self.vcsthread.paused.wait()

        if self.fm.image_displayer:
            self.fm.image_displayer.quit()

        self.win.keypad(0)
        curses.nocbreak()
        curses.echo()
        try:
            curses.curs_set(1)
        except curses.error:
            pass
        if self.settings.mouse_enabled:
            _setup_mouse(dict(value=False))
        curses.endwin()
        self.is_on = False

    def set_load_mode(self, boolean):
        boolean = bool(boolean)
        if boolean != self.load_mode:
            self.load_mode = boolean

            if boolean:
                # don't wait for key presses in the load mode
                curses.cbreak()
                self.win.nodelay(1)
            else:
                self.win.nodelay(0)
                # Sanitize halfdelay setting
                halfdelay = min(255, max(1, self.settings.idle_delay // 100))
                curses.halfdelay(halfdelay)

    def destroy(self):
        """Destroy all widgets and turn off curses"""
        if 'vcsthread' in self.__dict__:
            if not self.vcsthread.stop():
                self.fm.notify('Failed to stop `UI.vcsthread`', bad=True)
            del self.__dict__['vcsthread']
        DisplayableContainer.destroy(self)

        if self.multiplexer is not None:
            self.handle_multiplexer(self.multiplexer, restore_required=True)

        self.suspend()

    def handle_mouse(self):
        """Handles mouse input"""
        try:
            event = MouseEvent(curses.getmouse())
        except curses.error:
            return
        if not self.console.visible:
            DisplayableContainer.click(self, event)

    def handle_key(self, key):
        """Handles key input"""
        self.hint()

        if key < 0:
            self.keybuffer.clear()

        elif not DisplayableContainer.press(self, key):
            self.keymaps.use_keymap('browser')
            self.press(key)

    def press(self, key):
        keybuffer = self.keybuffer
        self.status.clear_message()

        keybuffer.add(key)
        self.fm.hide_bookmarks()
        self.browser.draw_hints = not keybuffer.finished_parsing \
            and keybuffer.finished_parsing_quantifier

        if keybuffer.result is not None:
            try:
                self.fm.execute_console(
                    keybuffer.result,
                    wildcards=keybuffer.wildcards,
                    quantifier=keybuffer.quantifier,
                )
            finally:
                if keybuffer.finished_parsing:
                    keybuffer.clear()
        elif keybuffer.finished_parsing:
            keybuffer.clear()
            return False
        return True

    def handle_keys(self, *keys):
        for key in keys:
            self.handle_key(key)

    def handle_input(self):  # pylint: disable=too-many-branches
        key = self.win.getch()
        if key == curses.KEY_ENTER:
            key = ord('\n')
        if key == 27 or (key >= 128 and key < 256):
            # Handle special keys like ALT+X or unicode here:
            keys = [key]
            previous_load_mode = self.load_mode
            self.set_load_mode(True)
            for _ in range(4):
                getkey = self.win.getch()
                if getkey != -1:
                    keys.append(getkey)
            if len(keys) == 1:
                keys.append(-1)
            elif keys[0] == 27:
                keys[0] = ALT_KEY
            if self.settings.xterm_alt_key:
                if len(keys) == 2 and keys[1] in range(127, 256):
                    if keys[0] == 195:
                        keys = [ALT_KEY, keys[1] - 64]
                    elif keys[0