#!/bin/bash

if [[ $(type -t gsu_is_a_number) != "function" ]]; then
	GSU_DIR=${GSU_DIR:=$HOME/.gsu}
	. $GSU_DIR/common || exit 1
fi

export GSU_NODE_NAME_PATTERN='[a-zA-Z_]'

_get_geometry()
{
	local x y
	result="$(stty size)"
	if (($? != 0)); then
		gsu_msg "fatal: could not get terminal geometry"
		exit 1
	fi
	x="${result#* }"
	y="${result%% *}"
	(($x > 190)) && x=190
	result="$y $x"
}

gsu_infobox()
{
	_get_geometry
	dialog --infobox "$1" $result
}

gsu_checklist_all_on()
{
	local header="$1"
	local items="$2"
	local i state opts num=0

	_get_geometry
	ops="$result 16"
	for i in $items; do
		let num++
		opts+=" $i $num on"
	done
	result=$(dialog --checklist "$header" $opts 3>&1 1>&2 2>&3 3>&-)
	ret="$?"
}

gsu_radiolist()
{
	local header="$1"
	local selected_item="$2"
	local items="$3"
	local i state ops num=0

	_get_geometry
	ops="$result 16"
	for i in $items; do
		let num++
		if [[ "$i" == "$selected_item" ]]; then
			state="on"
		else
			state="off"
		fi
		ops+=" $i $num $state"
	done
	result=$(dialog --radiolist "$header" $ops 3>&1 1>&2 2>&3 3>&-)
	ret="$?"
}

gsu_inputbox()
{
	local g text="$1" init="$2"

	_get_geometry
	g="$result"
	result="$(dialog --inputbox "$text" $g "$init" 3>&1 1>&2 2>&3 3>&-)"
	ret="$?"
}

gsu_textbox()
{
	local file="$1"

	_get_geometry
	dialog --textbox "$file" $result
}

# dialog segfaults if message is too long. Hence we always use a temporary file
gsu_msgbox()
{
	local tmp="$(mktemp gsu_msgbox.XXXXXXXXXX)"

	if (($? != 0)); then
		dialog --msgbox "mktemp error" 0 0
		return
	fi
	echo "$1" > "$tmp"
	gsu_textbox "$tmp"
	rm -f "$tmp"
}

gsu_cmd_output_box()
{
	local tmp="$(mktemp)"

	if (($? != 0)); then
		dialog --msgbox "mktemp error" 0 0
		return
	fi
	$@ > "$tmp" 2>&1
	echo "exit code: $?" >> "$tmp"
	gsu_textbox "$tmp"
	rm -f "$tmp"
}

gsu_yesno()
{
	local text="$1"

	_get_geometry
	dialog --yesno "$text" $result
	ret=$?
	if (($ret == 0)); then
		result="yes"
	elif (($ret == 1)); then
		result="no"
	else
		result=
	fi
}

gsu_menu()
{
	local header="${1:-root}"
	local items="$2"
	local i state opts num=0

	_get_geometry
	opts="$result 16"
	for i in $items; do
		let num++
		opts+=" $i $num"
	done
	result="$(dialog --menu "$gsu_banner_txt ($header)" $opts 3>&1 1>&2 2>&3 3>&-)"
	ret="$?"
}

_get_level()
{
	local tmp="${1%%$GSU_NODE_NAME_PATTERN*}"
	result="${#tmp}"
}

_get_subtree()
{
	local tree="$1" root="${2%/}"
	local TAB='	'

	first="$(grep -n "$TAB\{1,\}$root/" <<< "$tree")"
	[[ -z "$first" ]] && return

	line_num="${first%%:*}"
	_get_level "${first#*:}"
	level="$result"

	#echo "line: $line_num, root: $root, indent level: $level"
	result="$(sed -e "1,${line_num}d;" <<< "$tree" \
		| sed -e "/^$TAB\{1,$level\}$GSU_NODE_NAME_PATTERN/,\$d" \
		| sed -e "/^$TAB\{$(($level + 2))\}/d")"
	ret="$level"
}

_get_root_nodes()
{
	local tree="$1" TAB='	'

	result="$(grep "^${TAB}${GSU_NODE_NAME_PATTERN}" <<< "$tree")"
}

_browse()
{
	local header="$1" old_header
	local tree="$2" subtree="$3"

	while :; do
		gsu_menu "$header" "$subtree"
		(($ret != 0)) && return
		[[ -z "$result" ]] && return
		if [[ "${result%/}" != "$result" ]]; then
			old_header="$header"
			header="$result"
			_get_subtree "$tree" "$header"
			_browse "$header" "$tree" "$result"
			header="$old_header"
			continue
		fi
		eval ${gsu_name}_$result
	done
}

gsu_gui()
{
	local tree="$1" subtree

	_gsu_setup
	type -t dialog &> /dev/null
	if (($? != 0)); then
		gsu_msg "dialog executable not found"
		exit 1
	fi
	_get_root_nodes "$tree"
	subtree="$result"
	_browse "main menu" "$tree" "$subtree"
}