#!/bin/bash
#
#   CDM: The Console Display Manager
#
#   Copyright (C) 2009, Daniel J Griffiths <ghost1227@archlinux.us>
#   Thanks to:
#	Andrwe..........beta-testing and submitting the fix for the all 
#			important X incrementation function
#	brisbin33.......code cleanup
#	tigrmesh........finding a critical issue with the gnome-session handler
#	Profjim.........several incredibly useful patches
#
#       This program is free software; you can redistribute it and/or modify
#       it under the terms of the GNU General Public License as published by
#       the Free Software Foundation; either version 2 of the License, or
#       (at your option) any later version.
#       
#       This program is distributed in the hope that it will be useful,
#       but WITHOUT ANY WARRANTY; without even the implied warranty of
#       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#       GNU General Public License for more details.
#       
#       You should have received a copy of the GNU General Public License
#       along with this program; if not, write to the Free Software
#       Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
#       MA 02110-1301, USA.

name="Console Display Manager"
ver="0.4.1"
info="\e[1;34m==>\e[1;37m"
error="\e[1;31m==>\e[1;37m"
success="\e[1;32m==>\e[1;37m"
reset="\e[0m"
# Ignore SIGINT (^C) and SIGTSTP (^Z)
trap "" 2 20

# Source cdm configuration
if [[ -f /etc/cdmrc ]]; then
	source /etc/cdmrc
	count=0
	while [[ ${count} -lt ${#userconfig[@]} ]]; do
		if [[ "$USER" == "${userconfig[${count}]}" ]]; then
			${userconfig[${count}]}
		fi
		let count=count+1
	done
	countfrom=${countfrom:-0}
else
	echo -e "${error} ERROR: A valid cdm configuration was not found!${reset}"
	echo -e "${info} Logging out.${reset}"
	sleep 3
	exit 1
fi

unset DIALOGRC
# Source theme file
if [[ ! -z ${theme} ]]; then
	if [[ -f /usr/share/cdm/themes/${theme} ]]; then
		DIALOGRC=/usr/share/cdm/themes/${theme}
	else
		echo -e "${info} Theme file ${theme} is invalid, reverting to default theme.${reset}"
	fi
fi
if [[ -z $DIALOGRC ]]; then
	if [[ -f /usr/share/cdm/themes/default ]]; then
		DIALOGRC=/usr/share/cdm/themes/default
	else
		echo -e "${info} A valid theme file was not found, using system defaults.${reset}"
	fi
fi

### Based on FreeBSD's /etc/rc.subr
##
# checkyesno var
#    Test $1 variable, and warn if not set to YES or NO.
#    Return 0 if it's "yes" (et al), nonzero otherwise.
#    to make default yes, do "checkyesno var yes"

checkyesno()
{
	local value=${!1}
	# debug "checkyesno: $1 is set to $value."
	if [[ -n $2 ]]; then
		value=${value:-$2}
	else
		value=${value:-no}
	fi
	case $value in
	#    "yes", "true", "on", or "1"
	[Yy][Ee][Ss]|[Tt][Rr][Uu][Ee]|[Oo][Nn]|1)
	return 0
	;;
	#    "no", "false", "off", or "0"
	[Nn][Oo]|[Ff][Aa][Ll][Ss][Ee]|[Oo][Ff][Ff]|0)
	return 1
	;;
	*)
	echo "\$${1} is not set properly." >&2
	exit 1
	;;
	esac
}

# If X is already running and locktty=yes, activate it,
# otherwise, increment.
if $(checkyesno locktty); then
	# Verify display exists
	if [[ -n "${display//[0-9]/}" ]]; then
		display=0
	fi
	# Activate existing X session
	if xdpyinfo -display :${display}.0 &> /dev/null; then
		let tty=display+xtty
		chvt ${tty}
		exit 0
	fi
else
	# Get the first empty display
	display=0
	while [[ ${display} -lt 7 ]]; do
		if xdpyinfo -display :${display}.0 &> /dev/null; then
			let display=display+1
		else
			break
		fi
	done
fi

mainmenu() {
	# Generate main menu
	count=0
	menu=$(
		while [[ ${count} -lt ${#wmdisplist[@]} ]]; do
			echo -ne "$((count+countfrom)) ${wmdisplist[${count}]} "
			let count=count+1
		done
	)

	# Check if console access is allowed
	if $(checkyesno allowconsole); then
		if ! $(checkyesno allowshutdown); then
			let halt=99
		fi
		let console=${#wmdisplist[@]}+countfrom
		menu="${menu} ${console} Console "
	fi

	# Check if shutdown access is allowed
	if $(checkyesno allowshutdown); then
		if ! $(checkyesno allowconsole); then
			let halt=${#wmdisplist[@]}
		else
			let halt=${#wmdisplist[@]}+1
		fi
		let halt=halt+countfrom
		menu="${menu} ${halt} Shutdown "
	fi
	
	# Override dialog display if only one option is available
	if ! $(checkyesno allowconsole) && ! $(checkyesno allowshutdown) && [[ ${#wmdisplist[@]} == 1 ]]; then
		wm=$countfrom
	else
		# Display selection dialog
		wm=$(
			DIALOGRC="$DIALOGRC" dialog --colors \
			--backtitle "${name} v${ver}" --stdout \
			--ok-label " Select " --cancel-label " Logout " \
			--menu "Select Window Manager" 0 0 0 ${menu}
		)
		if [[ $? != 0 ]]; then
			clear
			exit 0
		fi
	fi

	# Set wm_bin
	clear
	if [[ ${wm} -eq ${console} ]]; then
		exec ${SHELL}
	elif [[ ${wm} -eq ${halt} ]]; then
		shutdownmenu
	else
		let wm=wm-countfrom
		wm_bin="${wmbinlist[${wm}]}"
		xstart
	fi
}

shutdownmenu() {
	count=$countfrom
	haltmenu=$(
		for opt in Shutdown Reboot Suspend; do
			# Check if suspend is enabled
			if [[ $opt != Suspend ]] || $(checkyesno allowsuspend); then
				echo -ne "$count $opt "
				let count=count+1
			fi
		done
	)

	# Display shutdown dialog
	haltopt=$(
		DIALOGRC="$DIALOGRC" dialog --colors \
		--backtitle "${name} v${ver}" --stdout \
		--ok-label " Select " --cancel-label " Cancel " \
		--menu "Shutdown" 0 0 0 ${haltmenu}
	)
	
	if [[ $? == 0 ]]; then
		clear
		if [[ ${haltopt} -eq $countfrom ]]; then
			${shutdowncommand}
		elif [[ ${haltopt} -eq $((countfrom+1)) ]]; then
			${rebootcommand}
		else
			${suspendcommand}
		fi
	else
		mainmenu
	fi
}

xstart() {
	# Start X
	serverargs=":${display} ${serverargs} vt$((xtty+display))"

	if $(checkyesno loginshell); then
		if [[ ${wm_bin} == "gnome-session" ]]; then
			exec ck-launch-session bash --login -c "startx /usr/share/cdm/xinirc "$wm_bin" -- ${serverargs} &> /dev/null" &
		else
			exec bash --login -c "startx /usr/share/cdm/xinitrc "$wm_bin" -- ${serverargs} &> /dev/null" &
		fi
	else
		if [[ ${wm_bin} == "gnome-session" ]]; then
			exec ck-launch-session startx /usr/share/cdm/xinitrc $wm_bin -- ${serverargs} &> /dev/null &
		else
			exec startx /usr/share/cdm/xinitrc $wm_bin -- ${serverargs} &> /dev/null &
		fi
	fi
}
mainmenu