#!/bin/bash
# Made by Andrew Shark, The author of LinuxComp Tutorial Youtube channel

# To install amdgpu-pro on ubuntu 19.04 we want to use the following:
# ./amdgpu-install --pro --opencl=lagacy,pal
# But there are several problems:
# 1) amdgpu-dkms fails to build in 19.10 (probably could be fixed, I did not explored it yet). I checked that this driver actually works without dkms version of amdgpu kernel modules, so solution is omitting it.
# 2) amdgpu-core checks ubuntu version before installation and refuses to continue if ubuntu version is not 18.04. Solution is to remove this check. It is in preinst script.
# 3) amdgpu-pro(-hwe) and amdgpu-pro-lib32 depends on amdgpu(-hwe), however they should depend on amdgpu-lib(-hwe) instead. amdgpu(-hwe) itself depends on amdgpu-dkms and amdgpu-lib(-hwe). Because of this issue, amdgpu-dkms package is still in installation list when we use --no-dkms. So solution is to modify depends array of amdgpu-pro(-hwe) and amdgpu-pro-lib32. Or just use a fake empty amdgpu-dkms package.
# 4) Then we need to edit packages hashsums and filesizes of modified packages in Packages file and hashsums of Packages file in Release file.
# 5) And we need to edit amdgpu-install script to use hwe packages (they are more recent versions of non-hwe ones).
# After that we could install amdgpu-pro 19.10-785425 in ubuntu 19.04.
# Ok, lets start!

# remove installation if it was done previously
if command -v amdgpu-uninstall; then amdgpu-uninstall -y;
elif command -v amdgpu-pro-uninstall; then amdgpu-pro-uninstall -y; fi


# Solving problem 1:
# We just do not install it.


# Solving problem 2:
# ag_core_orig_md5=6181300cd4027e11cc6d807a85e0314b # original (with preinst script)
DEBFILE="amdgpu-core_19.10-785425_all.deb"
TMPDIR=`mktemp -d /tmp/deb.XXXXXXXXXX` || exit 1
OUTPUT=`basename "$DEBFILE" .deb`.no_ub_ver_chk.deb
dpkg-deb -x "$DEBFILE" "$TMPDIR"
dpkg-deb --control "$DEBFILE" "$TMPDIR"/DEBIAN
rm "$TMPDIR"/DEBIAN/preinst
rm $OUTPUT # remove modded deb if already exist
dpkg -b "$TMPDIR" "$OUTPUT"
rm -r "$TMPDIR"

# for some reason hashsum is different after every build. Not explored why yet. So I will get it in this script dinamically
ag_core_mod_md5=$(md5sum $OUTPUT | cut -f1 -d" ")
ag_core_mod_sha1=$(sha1sum $OUTPUT | cut -f1 -d" ")
ag_core_mod_sha256=$(sha256sum $OUTPUT | cut -f1 -d" ")
ag_core_mod_size=$(wc -c < $OUTPUT)


# Solving problem 3:
# ag_dkms_orig_md5=5a1a0330f609c1b927a212bd4b14a95a # original amdgpu-dkms_19.10-785425_all.deb package

rm -rf amdgpu-dkms-fake
mkdir -p amdgpu-dkms-fake/DEBIAN
echo -e "
Package: amdgpu-dkms
Version: 19.10-785425
Architecture: all
Maintainer: Unreal Person <you@email.com>
Section: misc
Priority: optional
Description: Fake empty package to workaround pro stack dependcy on dkms" > amdgpu-dkms-fake/DEBIAN/control
dpkg-deb --build amdgpu-dkms-fake > /dev/null
rm -rf amdgpu-dkms-fake

ag_dkms_mod_md5=$(md5sum amdgpu-dkms-fake.deb | cut -f1 -d" ")
ag_dkms_mod_sha1=$(sha1sum amdgpu-dkms-fake.deb | cut -f1 -d" ")
ag_dkms_mod_sha256=$(sha256sum amdgpu-dkms-fake.deb | cut -f1 -d" ")
ag_dkms_mod_size=$(wc -c < amdgpu-dkms-fake.deb)


# Solving problem 4:

sed -i "36{s/.*/Filename: .\/amdgpu-core_19.10-785425_all.no_ub_ver_chk.deb/}" Packages
sed -i "37{s/.*/Size: $ag_core_mod_size/}" Packages
sed -i "38{s/.*/MD5sum: $ag_core_mod_md5/}" Packages
sed -i "39{s/.*/SHA1: $ag_core_mod_sha1/}" Packages
sed -i "40{s/.*/SHA256: $ag_core_mod_sha256/}" Packages

sed -i "52{s/.*/Filename: .\/amdgpu-dkms-fake.deb/}" Packages
sed -i "53{s/.*/Size: $ag_dkms_mod_size/}" Packages
sed -i "54{s/.*/MD5sum: $ag_dkms_mod_md5/}" Packages
sed -i "55{s/.*/SHA1: $ag_dkms_mod_sha1/}" Packages
sed -i "56{s/.*/SHA256: $ag_dkms_mod_sha256/}" Packages

# packages_mod_md5=$(md5sum Packages | cut -f1 -d" ")
# packages_mod_sha1=$(sha1sum Packages | cut -f1 -d" ")
packages_mod_sha256=$(sha256sum Packages | cut -f1 -d" ")
packages_mod_sha1=$(sha1sum Packages | cut -f1 -d" ")
packages_mod_size=$(wc -c < Packages)

echo -e "Date: `date -R -u` 
SHA256:
 $packages_mod_sha256 $packages_mod_size Packages" > Release

# Solving problem 5:
sed -i '147{s/^\t/#/}' amdgpu-install # commenting out this condition: if dpkg -s "xserver-xorg-hwe-18.04"
sed -i '151{s/^\t/#/}' amdgpu-install # and its closing fi


# Finally, we are ready to install:
./amdgpu-install --pro --opencl=legacy,pal --no-dkms
sudo ldconfig