#!/bin/bash

get_thread() {
	cat /proc/cpuinfo 2> /dev/null | grep MHz | wc -l
}

get_governor() {
	cat /sys/devices/system/cpu/cpufreq/policy0/scaling_governor 2> /dev/null
}

set_governor() {
	for i in $(seq $(get_thread))
	do
		i=$(( $i - 1 ))
		echo $1 > /sys/devices/system/cpu/cpufreq/policy${i}/scaling_governor 2> /dev/null
		[[ $? != 0 ]] && return 1
	done
	return 0
}

list_available_governor() {
	cat /sys/devices/system/cpu/cpufreq/policy0/scaling_available_governors 2> /dev/null
}

list_available_freq() {
	cat /sys/devices/system/cpu/cpufreq/policy0/cpuinfo_${1}_freq 2> /dev/null
}

check_governor() {
	for i in $(list_available_governor)
	do
		[[ $1 == $i ]] && return 0
	done
	return 1
}

list_available_freq() {
	cat /sys/devices/system/cpu/cpufreq/policy0/cpuinfo_${1}_freq 2> /dev/null
}

get_freq() {
	case $1 in
	cur)
		cat /sys/devices/system/cpu/cpufreq/policy${1}/scaling_cur_freq 2> /dev/null
	;;
	min | max)
		cat /sys/devices/system/cpu/cpufreq/policy0/scaling_${1}_freq 2> /dev/null
	;;
	esac
}

set_freq() {
	for i in $(seq $(get_thread))
	do
		i=$(( $i - 1 ))
		echo $2 > /sys/devices/system/cpu/cpufreq/policy${i}/scaling_${1}_freq 2> /dev/null
		[[ $? != 0 ]] && return 1
	done
	return 0
}

help() {
	case $1 in
	governor)
		case $2 in
		set)
			echo "Usage: $0 governor set < $(list_available_governor)>"
		;;
		*)
			echo "Usage: $0 governor [ls] [show] [set]"
		;;
		esac
	;;
	freq)
		case $2 in
		set)
			echo "Usage: $0 freq set [min] [max] <number[$(( $(list_available_freq min) / 100000 ))-$(( $(list_available_freq max) / 100000 ))]>"
		;;
		*)
			echo "Usage: $0 freq [ls] [set] [show]"
		;;
		esac
	;;
	*)
		echo "Usage: $0 [governor] [freq]"
	;;
	esac
	exit
}

case $1 in
governor)
	case $2 in
	ls)
		echo "Available governor: $(list_available_governor)"
	;;
	show)
		for i in $(seq $(get_thread))
		do
			i=$(( $i - 1 ))
			echo CPU$i $(get_governor $i) $(get_freq cur $i)
		done
	;;
	set)
		if [[ $(check_governor $3; echo $?) == 0 ]]
		then
			set_governor $3 || echo "Failed to set CPU governor to $3 ..."
		else
			help $1 $2
		fi
	;;
	*)
		help $1
	;;
	esac
;;
freq)
	case $2 in
	ls)
			echo "Available Min frequency: $(list_available_freq min)"
			echo "Available Max frequency: $(list_available_freq max)"
	;;
	show)
		case $3 in
		min | max)
			get_freq $3
		;;
		*)
			get_freq min
			get_freq max
		;;
		esac
	;;
	set)
		case $3 in
		min | max)
			if [[ $4 =~ [0-9] && $4 != 0 && $4 -lt 99 ]] 2> /dev/null
			then
				set_freq $3 ${4}00000 || echo "Failed to set CPU frequency to $4 ..."
			else
				echo "Unknown freq number: [$4]"
			fi
		;;
		reset)
			set_freq min $(list_available_freq min)
			set_freq max $(list_available_freq max)
		;;
		*)
			help $1 $2
		esac
	;;
	*)
		help $1
	;;
	esac
;;
*)
	help
;;
esac