#! /bin/bash

declare -A conf
conf[ATEXIT_MAX]=16
conf[RTC_CB_ARRAY_SIZE]=5
conf[EVENTS_QUEUE_SIZE]=64
conf[GINT_NO_SYSCALLS]=
conf[GINT_EXTENDED_LIBC]=
fail=false
output_gcc="gcc.cfg"
output_make="Makefile.cfg"

error="\e[31;1merror:\e[0m"
Cr="$(tput setaf 1)$(tput bold)"
Cg="$(tput setaf 2)$(tput bold)"
Cp="$(tput setaf 5)$(tput setaf 62)$(tput bold)"
C0="$(tput setaf 0)$(tput sgr 0)"

help()
{
	cat << EOF
Configuration script for the gint library.

Options that affect the behavior of the library:
  $Cr--no-syscalls$C0  [default:$Cp false$C0]
        Never use syscalls. Expect some trouble with the malloc() function...
        Do not enable this option unless you know what you are doing.
  $Cr--extended-libc$C0  [default:$Cp false$C0]
	Enable specific C99 headers/features that are normally not required by
        calculator programs. May allow porting programs from other platforms.

Options that customize size limits:
  $Cr--atexit-max=$C0$Cg<integer>$C0  [default:$Cp 16$C0]
        Number of exit handlers that can be registered by atexit().
  $Cr--rtc-callbacks=$C0$Cg<integer>$C0  [default:$Cp 5$C0]
        Number of RTC callbacks that can be registered.
  $Cr--events-queue-size=$C0$Cg<integer>$C0  [default:$Cp 64$C0]
        Number of events simultaneously stored in the event queue.
EOF

	exit 0
}

for arg; do case "$arg" in
	-h | --help) help;;
	--no-syscalls) conf[GINT_NO_SYSCALLS]=true;;
	--extended-libc) conf[GINT_EXTENDED_LIBC]=true;;

	--atexit-max=*)
		size=${arg#*=}
		if [[ $size == +([0-9]) ]]; then
			conf[ATEXIT_MAX]=$size
		else echo -e "$error --atexit-max expects an integer value"
			fail=true; fi;;
	--rtc-callbacks=*)
		size=${arg#*=}
		if [[ $size == +([0-9]) ]]; then
			conf[RTC_CB_ARRAY_SIZE]=$size
		else echo -e "$error --rtc-callbacks expects an integer value"
			fail=true; fi;;
	--events-queue-size=*)
		size=${arg#*=}
		if [[ $size == +([0-9]) ]]; then
			conf[EVENTS_QUEUE_SIZE]=$size
		else echo -e "$error --events-queue-size expects an integer"\
			"value"
			fail=true; fi;;

	--atexit-max | --rtc-callbacks | --events-queue-size)
		echo -e "$error syntax for $arg is $arg=<integer-value>";;

	*)
		echo -e "$error unrecognized argument '$arg'"; fail=true;;
esac; done

output_config_gcc()
{
	echo "-D ATEXIT_MAX=${conf[ATEXIT_MAX]}"
	echo "-D RTC_CB_ARRAY_SIZE=${conf[RTC_CB_ARRAY_SIZE]}"
	echo "-D EVENTS_QUEUE_SIZE=${conf[EVENTS_QUEUE_SIZE]}"
	if [ "${conf[GINT_NO_SYSCALLS]}" != "" ]; then
		echo "-D GINT_NO_SYSCALLS"
	fi
	if [ "${conf[GINT_EXTENDED_LIBC]}" != "" ]; then
		echo "-D GINT_EXTENDED_LIBC"
	fi
}

output_config_make()
{
	[ "${conf[GINT_EXTENDED_LIBC]}" != "" ] && echo "config_ext=true"
}

if $fail; then
	echo "Configuration has not been modified."
else
	output_config_gcc > $output_gcc
	output_config_make > $output_make
	echo "Configuration saved in $output_gcc and $output_make."
fi