Either the selected file was changed, or a file or directory was chosen
(and the Enter key virtually pressed), or a shortcut was executed.  So,
just go and read the next key.

This fixes https://savannah.gnu.org/bugs/?47944.

If during startup there are multiple error messages, currently only the
last one remains and can be read.  To improve on that, introduce a short
pause between error messages -- even if it's not enough to read them all,
at least the user will be aware that there are multiple ones.

This also causes a few error messages to beep that currently don't beep,
such as when a file is unwritable.

When doing a PageUp or PageDown in the browser, don't move the highlight
to the first line in the same column, but keep it in the same relative
position of the screen.  If we're already on the first or last page,
move the highlight to the first or last line, but keep it in the same
column.  If we're already on the first or last line, only then move it
to the first or last entry.

To separate things that have little to do with each other.

When compiled with --disable-justify, try to keep the vertical pairing
of related items.

This fixes https://savannah.gnu.org/bugs/?47933.

This fixes https://savannah.gnu.org/bugs/?47932.

CONST_UPDATE is only relevant when in the main menu, not when in the
browser.  So, check for that condition, instead of saving, changing,
and then restoring the setting.

CONST_UPDATE does not need to influence the delay for blanking the
statusbar; it is enough when it simply prevents it.

When in the browser, typing keys that produce an unknown escape sequence
should not switch on the cursor.

Take the side effect of a 'statusbar' call -- setting suppress_cursorpos
to TRUE -- into account.  This effect was overlooked by commit 9d6d5b67.

The function 'bottombars' has already done this.

An interactive 'gotolinecolumn' has already refreshed the screen.

There is no need to iterate through all the file names, as we already
know the length of the longest.  From this it's easy to calculate how
many names fit on a line.

Also rename some things to be more fitting.  And make sure that something
will be selected even when many files, including the selected one, have
disappeared.

When refreshing the screen (and thus the file list), use the prev_dir
mechanism to reselect the file that was selected before the refresh,
to prevent the selection from changing when files were added or deleted.

Also, when the selected name has disappeared, move the highlight one step
back, so that it is obvious that the selection has changed.  (Decrementing
'selected' will never make it negative, because selected == 0 means the
'..' entry, and every directory has a '..' entry, so it will be found.)

This fixes https://savannah.gnu.org/bugs/?47812

.

Signed-off-by: Rishabh Dave <rishabhddave@gmail.com
Signed-off-by: Benno Schulenberg <bensberg@justemail.net>

When during searching we look at the keyboard, then don't look at
just the first keystroke, but check if there are more, and if so,
check each one until we find a Cancel -- or until all keystrokes
have been consumed and we can continue.

This fixes the first half of https://savannah.gnu.org/bugs/?47438.

Cancelling a search should restore waiting mode for the keyboard,
just like at the other exit points of the search routine.

And when the input routine has read in multiple keystrokes, it
should not blindly switch back to waiting mode, but only when
that mode was on before.

This fixes the second half of https://savannah.gnu.org/bugs/?47438.

When the terminal is very narrow, there is little point in showing only
part of the version string -- and chewing off one or two digits from the
version number might even give someone a wrong idea.  The user is better
served with always showing the full filename, as long as it fits in the
available screen width.

This fixes https://savannah.gnu.org/bugs/?47703.

Also remove the item about one Replacement Character per invalid UTF-8
sequence, because how many bytes form a sequence?  Two?  Three?  Four?
Better just put one Replacement Character per invalid byte, like is
done now.

When fixing a misspelling and not answering 'All' (but 'Yes' or 'No'),
the chance is quite substantial that one will type y or n at the end of
the next word.  Diminish this chance by showing for a moment a message
on the statusbar.

Partitioning the file makes the undo system lose track, so that undoing
things has a good chance of losing data.  Instead, just make sure that
the region is marked "backwards", with current at the top and the mark
at the bottom, and then let the replace loop take care of not going
outside of the marked region.

This also has the effect that if the marked region fits entirely on the
screen, or all the misspellings are onscreen, then the screen will not
be scrolled at all.  Which makes for a smooth experience.

This fixes https://savannah.gnu.org/bugs/?47836,
and fixes https://savannah.gnu.org/bugs/?45573.

Since nano-2.4.1, reading in or pasting a large piece of text would put
the cursor on the bottom line, leaving only one line of the non-read or
non-pasted text visible.  This is different from the centering behavior
of Pico, and somewhat disorienting, as you can't see "where you are" any
more in relation to the file as it was.

So now center the cursor whenever the read or pasted text is larger than
the screen, but don't center it when the text fits entirely on the screen.
(The latter avoids the effect of the screen jumping unnecessarily when
inserting just a few lines while the cursor is near the bottom.)

To achieve this behavior: default to focusing, and temporarily set it to
FALSE when the focusing effect is unwanted.

This fixes https://savannah.gnu.org/bugs/?47841.

For some reason the keyboard code seems to assume that all integers
waiting in the keybuffer form a single sequence.  But this isn't the
case: when there is an escape (0x1b) among them, then that is where
a new sequence starts.  So, prevent the input code from considering
an escape after a non-escape as part of the current sequence.

This fixes https://savannah.gnu.org/bugs/?47839.