#!/usr/bin/bash

EDITION="linux-lts54"

RAMDISK_PATH="/run/user/$(id -u)/tmp"
RAMDISK="$RAMDISK_PATH/$EDITION"
SCRIPTPATH=$( cd "$(dirname "${BASH_SOURCE[0]}")" ; pwd -P )
N="ionice -c3 nice -n19 chrt -i 0"

clean_ramdisk() {
    pushd . >/dev/null
    cd "$RAMDISK_PATH" || exit 1
    rm -rf ./"$EDITION"
    popd >/dev/null
}

uname -a

if [ "$1" != "nowait" ]; then
	echo ""
	pacolog -l 3 $EDITION
	sleep 8
else
	shift
fi

# Delete any old PKGBUILD and start fresh
cd "$SCRIPTPATH" || exit 1
[ -d "$RAMDISK_PATH" ] && clean_ramdisk
mkdir -p "$RAMDISK" || exit 1
rm -f "$EDITION"
ln -s "$RAMDISK" "$EDITION"

# Check for aur*.tar.gz file
AUR=$(find . -maxdepth 0 -name "aur-*.tar.gz" | head -1)

if [ -n "$AUR" ]; then
	echo "*** Using file $AUR as package source"
	cd "$EDITION" || exit 1
	tar xvzf "$SCRIPTPATH/$AUR"
	mv aur-*/{*,.SRCINFO} .
	rmdir $(find -type d -name "aur-*")
else
	echo -e "\n*** Building most current kernel version available"
	yay -G "$EDITION"
	cd "$EDITION" || exit 1
fi

cp "$SCRIPTPATH/linux-5.4."*.tar.xz . 2>/dev/null || true
cp "$SCRIPTPATH/patches/"* .

# Edit PKGBUILD to change group and package name
mv PKGBUILD PKGBUILD.ORIG
awk -v edition="$EDITION" '
	/^pkgbase=linux/ {
		print "pkgbase="edition"-custom\ngroups=(" "\x27" "custom" "\x27" ")\n";
		next
	}
    /make htmldocs/ {
        printf "# %s\n",$0
        next
    }
    /^pkgname=/ {
        sub(/ ?"\$pkgbase-docs"/,"",$0)
        print $0
        next
    }
    /sphinx-workaround.patch/ {
        print "  sphinx-workaround.patch"
        print "  1000-wireguard.patch"
        print "  1001-ath9k-regd.patch"
        print "  1002-ath9k-powerlimits.patch"
        print "  1003-ath9k-antenna-reduction.patch"
        print "  1004-gpio_keys_polled.patch"
        print "  1005-pcengines-54.patch"
        print "  1006-mlx4.patch"
        next
    }
    /b7c814c8183e4645947a6dcc3cbf80431de8a8fd4e895b780f9a5fd92f82cb8e/ {
        print "            \047b7c814c8183e4645947a6dcc3cbf80431de8a8fd4e895b780f9a5fd92f82cb8e\047"
        print "            \047SKIP\047"
        print "            \047SKIP\047"
        print "            \047SKIP\047"
        print "            \047SKIP\047"
        print "            \047SKIP\047"
        print "            \047SKIP\047"
        print "            \047SKIP\047)"
        next
    }
	{
		print $0
	}' < PKGBUILD.ORIG > PKGBUILD

# Delete sha256 sum for config file which we will modify
SUM=$(sha256sum config | awk '{ printf $1 }')
sed -i 's/'${SUM}'/SKIP/g' PKGBUILD
diff -Nurp PKGBUILD.ORIG PKGBUILD
PKGVER=$(grep ^pkgver= PKGBUILD | awk -F= '{ printf "%s",$2 }')
rm PKGBUILD.ORIG

# Modify kernel configuration
cat <<EOF >>config
CONFIG_PINCTRL_AMD=y
CONFIG_WIREGUARD=y
# CONFIG_WIREGUARD_DEBUG is not set

CONFIG_ATH_DEBUG=y
CONFIG_ATH_REG_DYNAMIC_USER_REG_HINTS=y
CONFIG_ATH_REG_DYNAMIC_USER_CERT_TESTING=y

CONFIG_CFG80211_CERTIFICATION_ONUS=y
CONFIG_CFG80211_REQUIRE_SIGNED_REGDB=n
CONFIG_CFG80211_REG_RELAX_NO_IR=y
EOF

if [ "$1" = "debug" ]; then
	echo -e "\nBuilding kernel with full debug info.\n"
	cat <<EOF >>config

CONFIG_CRASH_DUMP=y
CONFIG_PROC_VMCORE=y
CONFIG_DEBUG_INFO=y
CONFIG_DEBUG_INFO_REDUCED=n
CONFIG_DEBUG_INFO_SPLIT=n
CONFIG_DEBUG_INFO_DWARF4=n
CONFIG_GDB_SCRIPTS=n
EOF
fi

# Build package
time $N makepkg || {
    cd "$SCRIPTPATH" || exit 1
    clean_ramdisk
    exit 1
}

# Move final package files and clean up
PKGS=$(ls "$EDITION"*.zst)
mv -f $PKGS "$SCRIPTPATH"

cd "$SCRIPTPATH" || exit 1

if [ "$1" = "debug" ]; then
	echo -e "\nCompressing crash debug kernel image..."
	VMK="$EDITION/src/linux-$PKGVER/vmlinux"
	chmod 0644 "$VMK"
	$N gzip "$VMK"
	mv "$VMK".gz .
fi

echo ""
df -h | grep -E "^Filesystem|run/user"
echo ""
df -i | grep -E "^Filesystem|run/user"
echo ""

rm -f "$EDITION"
clean_ramdisk

# Install packages
echo Press return to install...
read -r
if [ "$1" = "debug" ]; then
	sudo mkdir -p /var/crash
    sudo cp -f "$VMK".gz /var/crash/
else
	rm -f vmlinux.gz
    rm -f /var/crash/vmlinux.gz
fi
sudo pacman -U $PKGS