#!/bin/bash

: <<'_EOS'
=pod
=cut

=head1 NAME

fanspeed - set fanspeed using IPMI

=head1 SYNOPSIS

B<fanspeed> I<degrees>C

B<fanspeed> I<percent>

B<fanspeed> bios


=head1 DESCRIPTION

B<fanspeed> will set the fanspeed using IPMI.


=head1 OPTIONS

=over 9

=item I<degrees>C

Run fans at 40% unless temperature goes above I<degrees>. When that
happens: Let BIOS control the fan for 30 seconds.


=item I<percent>

Run fans at I<percent> percent.


=item bios

Let BIOS control the fans.


=back


=head1 EXAMPLES

=head2 EXAMPLE: 

Run fans at 40% unless temperature is above 60C. When temperature is
above 60C, let BIOS control fans.

    fanspeed 60C


=head2 EXAMPLE: Run fans at 50%

    fanspeed 50


=head2 EXAMPLE: Let BIOS control fans

    fanspeed bios


=head1 REPORTING BUGS

Report bugs: https://gitlab.com/ole.tange/tangetools/-/issues


=head1 AUTHOR

Copyright (C) 2020 Ole Tange, http://ole.tange.dk and Free
Software Foundation, Inc.


=head1 LICENSE

Copyright (C) 2013 Free Software Foundation, Inc.

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 3 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, see <http://www.gnu.org/licenses/>.

=head2 Documentation license I

Permission is granted to copy, distribute and/or modify this documentation
under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with no
Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
Texts.  A copy of the license is included in the file fdl.txt.

=head2 Documentation license II

You are free:

=over 9

=item B<to Share>

to copy, distribute and transmit the work

=item B<to Remix>

to adapt the work

=back

Under the following conditions:

=over 9

=item B<Attribution>

You must attribute the work in the manner specified by the author or
licensor (but not in any way that suggests that they endorse you or
your use of the work).

=item B<Share Alike>

If you alter, transform, or build upon this work, you may distribute
the resulting work only under the same, similar or a compatible
license.

=back

With the understanding that:

=over 9

=item B<Waiver>

Any of the above conditions can be waived if you get permission from
the copyright holder.

=item B<Public Domain>

Where the work or any of its elements is in the public domain under
applicable law, that status is in no way affected by the license.

=item B<Other Rights>

In no way are any of the following rights affected by the license:

=over 2

=item *

Your fair dealing or fair use rights, or other applicable
copyright exceptions and limitations;

=item *

The author's moral rights;

=item *

Rights other persons may have either in the work itself or in
how the work is used, such as publicity or privacy rights.

=back

=back

=over 9

=item B<Notice>

For any reuse or distribution, you must make clear to others the
license terms of this work.

=back

A copy of the full license is included in the file as cc-by-sa.txt.

=head1 DEPENDENCIES

B<fanspeed> uses IPMItool, and sensors.


=head1 SEE ALSO

B<ipmitool>(1), jq(1), and B<sensors>(1).

=cut
_EOS

setfanspeed() {
    # 0..100 = manual control X%
    # bios = BIOS control
    ipmi() {
	DRAC_USER=${DRAC_USER:-root}
	DRAC_PASSWD=${DRAC_PASSWD:-calvin}
	DRAC_HOST=${DRAC_HOST:-drac}
	echo -n $(ipmitool -I lanplus -H "$DRAC_HOST" -U "$DRAC_USER" -P "$DRAC_PASSWD" raw "$@")
    }
    if [ "$1" == "bios" ] ; then
	# Let BIOS run the fan
	ipmi 0x30 0x30 0x01 0x01
    else
	# Manual control
	ipmi 0x30 0x30 0x01 0x00
	# Set speed 0..100
	ipmi 0x30 0x30 0x02 0xff "$@"
    fi
}

fanspeedthreshold() {
    # fanspeedthreshold deg
    # Turn on BIOS control when temperature reaches deg degrees
    sensors -j |
    	jq -r '[.[]["temp1"]["temp1_input"]] |
	   if max < '$1' then 40 else "bios" end';
}

runthreshold() {
    # runthreshold degrees
    while true; do
	printf " "$(sensors -j |
	    jq '[.[]["temp1"]["temp1_input"]] | max')
	speed=$(fanspeedthreshold $@)
	setfanspeed $speed
	if [ $speed == "bios" ] ; then
	    # Do not change away from bios in less than 30 secs
	    sleep 30
	fi
	sleep 1
    done
}


_fanspeed() {
    # BIOS = 60 C => 40
    # 0 C => 10, 55 C => 10, 65 C => 100
    sensors -j |
    	jq '[.[]["temp1"]["temp1_input"]] |
	   (max-55)*(100/(65-55)) |
	   if . < 50 then 50 else if . > 100 then 100 else .|floor end end';
#	   if . < 25 then 25 else if . > 100 then 100 else .|floor end end';
}

degrees=$(echo "$@" | perl -ne '/(\d+)C/i and print $1')

if [ -z "$degrees" ] ; then
    setfanspeed "$@"
else
    runthreshold "$degrees"
fi