#!/bin/sh

PATH=/bin:/usr/bin
TERM=screen
LC_ALL=C.UTF-8
export PATH TERM LC_ALL

[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
TMUX="$TEST_TMUX -Lentry-column-$$ -f/dev/null"

fail()
{
	echo "$mode: $*" >&2
	exit 1
}

cleanup()
{
	$TMUX kill-server 2>/dev/null
}
trap cleanup 0 1 15

x()
{
	$TMUX send-keys -X "$@" || fail "copy command failed: $*"
}

check_cursor()
{
	actual=$($TMUX display-message -p '#{copy_cursor_x},#{copy_cursor_y}')
	[ "$actual" = "$1" ] || fail "expected cursor $1, got $actual"
}

wait_cursor()
{
	i=0
	while [ "$i" -lt 50 ]; do
		actual=$($TMUX display-message -p '#{cursor_x},#{cursor_y}')
		[ "$actual" = "$1" ] && return 0
		sleep 0.1
		i=$((i + 1))
	done
	fail "pane cursor did not reach $1"
}

mode=emacs
$TMUX new-session -d -x40 -y10 \
    "printf '%s\r\n' ABCDEFGHIJKLMNOPQRST abc ABCDEFGHIJKLMNOPQRST \
	abcdefgh ABCDEFGHIJKLMNOP ab 01234567890123456789; \
	printf '\033[4;9H'; exec cat" ||
    fail "new-session failed"
$TMUX set-option -g status off || fail "set status failed"
$TMUX set-option -g window-size manual || fail "set window-size failed"
wait_cursor 8,3

for mode in emacs vi; do
	$TMUX set-window-option -g mode-keys "$mode" ||
	    fail "set mode-keys failed"

	# Ordinary entry still follows line ends; -c starts at the same physical
	# position but treats its column as a numeric preference.
	for direction in up down; do
		if [ "$direction" = up ]; then
			row=2
			end=20
		else
			row=4
			end=16
		fi
		[ "$mode" = emacs ] || end=$((end - 1))
		$TMUX copy-mode || fail "copy-mode failed"
		check_cursor 8,3
		x "cursor-$direction"
		check_cursor "$end,$row"
		x cancel

		$TMUX copy-mode -c || fail "copy-mode -c failed"
		check_cursor 8,3
		x "cursor-$direction"
		check_cursor "8,$row"
		x cancel
	done

	# Short lines retain the existing emacs and vi movement rules. Emacs
	# restores the preferred column; vi resumes from its last-character clamp.
	$TMUX copy-mode -c || fail "copy-mode -c failed"
	x cursor-up
	check_cursor 8,2
	x cursor-up
	if [ "$mode" = emacs ]; then
		check_cursor 3,1
		restored=8
	else
		check_cursor 2,1
		restored=2
	fi
	x cursor-up
	check_cursor "$restored,0"
	x cancel

	$TMUX copy-mode -c || fail "copy-mode -c failed"
	x cursor-down
	check_cursor 8,4
	x cursor-down
	if [ "$mode" = emacs ]; then
		check_cursor 2,5
		restored=8
	else
		check_cursor 1,5
		restored=1
	fi
	x cursor-down
	check_cursor "$restored,6"
	x cancel

	# Horizontal movement before the first vertical move replaces the initial
	# preference, rather than leaving the entry column permanently fixed.
	$TMUX copy-mode -c || fail "copy-mode -c failed"
	x cursor-left
	check_cursor 7,3
	x cursor-up
	check_cursor 7,2
	x cancel
done

# Passing -c while already in copy mode must not reinitialize its preference.
mode=emacs
$TMUX set-window-option -g mode-keys "$mode" || fail "set mode-keys failed"
$TMUX copy-mode -c || fail "copy-mode -c failed"
x cursor-left
x cursor-up
x cursor-up
check_cursor 3,1
$TMUX copy-mode -c || fail "second copy-mode -c failed"
check_cursor 3,1
x cursor-up
check_cursor 7,0
x cancel

# Trailing blanks must not replace the initial preference on the first move.
for entry_line in 'prompt> ' '        '; do
	$TMUX respawn-pane -k \
	    "printf '\033[H\033[2J'; \
		printf '%s\r\n' ABCDEFGHIJKLMNOPQRST abc ABCDEFGHIJKLMNOPQRST \
		    '$entry_line' ABCDEFGHIJKLMNOP ab 01234567890123456789; \
		printf '\033[4;9H'; exec cat" || fail "respawn-pane failed"
	wait_cursor 8,3
	for mode in emacs vi; do
		$TMUX set-window-option -g mode-keys "$mode" ||
		    fail "set mode-keys failed"
		for direction in up down; do
			if [ "$direction" = up ]; then
				row=2
				end=20
				short=3
				last=0
			else
				row=4
				end=16
				short=2
				last=6
			fi
			[ "$mode" = emacs ] || end=$((end - 1))
			$TMUX copy-mode || fail "copy-mode failed"
			x "cursor-$direction"
			check_cursor "$end,$row"
			x cancel

			$TMUX copy-mode -c || fail "copy-mode -c failed"
			check_cursor 8,3
			x "cursor-$direction"
			check_cursor "8,$row"
			x "cursor-$direction"
			x "cursor-$direction"
			if [ "$mode" = emacs ]; then
				check_cursor "8,$last"
			else
				check_cursor "$((short - 1)),$last"
			fi
			x cancel
		done

		# Returning to the entry mark must not reenable EOL following.
		$TMUX copy-mode -c || fail "copy-mode -c failed"
		x cursor-up
		check_cursor 8,2
		x jump-to-mark
		check_cursor 8,3
		$TMUX copy-mode || fail "second copy-mode failed"
		x cursor-up
		check_cursor 8,2
		x cancel

		# A new ordinary visit restores the default. Adding -c to an already
		# active visit does not change its policy.
		$TMUX copy-mode || fail "copy-mode failed"
		$TMUX copy-mode -c || fail "second copy-mode -c failed"
		x cursor-up
		end=20
		[ "$mode" = emacs ] || end=19
		check_cursor "$end,2"
		x cancel
	done
done

# An empty entry line has a numeric column zero with -c.
$TMUX respawn-pane -k \
    "printf '\033[H\033[2JABCDEFGHIJKLMNOPQRST\033[2;1H'; exec cat" ||
    fail "respawn-pane failed"
wait_cursor 0,1
for mode in emacs vi; do
	$TMUX set-window-option -g mode-keys "$mode" ||
	    fail "set mode-keys failed"
	$TMUX copy-mode -c || fail "copy-mode -c failed"
	check_cursor 0,1
	x cursor-up
	check_cursor 0,0
	x cancel
done

# The initial preference counts terminal columns, not characters.
$TMUX respawn-pane -k \
    "printf '\033[H\033[2J'; \
	printf '%s\r\n' ABCDEFGHIJKLMNOPQRST ABCDEFGHIJKLMNOPQRST; \
	printf 'abc中def'; exec cat" ||
    fail "respawn-pane failed"
wait_cursor 8,2
for mode in emacs vi; do
	$TMUX set-window-option -g mode-keys "$mode" ||
	    fail "set mode-keys failed"
	$TMUX copy-mode -c || fail "copy-mode -c failed"
	check_cursor 8,2
	x cursor-up
	check_cursor 8,1
	x cancel
done

# Initialize before the optional entry-time page movement.
$TMUX respawn-pane -k \
    "printf '\033[H\033[2JABCDEFGHIJKLMNOPQRST'; \
	printf '\033[9;1Hprompt> \033[10;1HABCDEFGHIJKLMNOP\033[9;9H'; \
	exec cat" ||
    fail "respawn-pane failed"
wait_cursor 8,8
for mode in emacs vi; do
	$TMUX set-window-option -g mode-keys "$mode" ||
	    fail "set mode-keys failed"
	$TMUX copy-mode -cu || fail "copy-mode -cu failed"
	check_cursor 8,0
	x cancel
	$TMUX copy-mode -cd || fail "copy-mode -cd failed"
	check_cursor 8,9
	x cancel
done

exit 0