#!/bin/bash

# Slackware build script for ddcci-driver-linux

# Copyright 2026 Julian Grinblat <julian@dotcore.com>
# All rights reserved.
#
# Redistribution and use of this script, with or without modification, is
# permitted provided that the following conditions are met:
#
# 1. Redistributions of this script must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
#
#  THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR IMPLIED
#  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
#  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
#  EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
#  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
#  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
#  OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
#  WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
#  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
#  ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

cd $(dirname $0) ; CWD=$(pwd)

PRGNAM=ddcci-driver-linux
VERSION=${VERSION:-0.4.5}
BUILD=${BUILD:-1}
TAG=${TAG:-_SBo}
PKGTYPE=${PKGTYPE:-tgz}

# Kernel this package builds/installs modules against when DKMS isn't used.
# Defaults to the kernel currently running on the build machine.
KERNEL=${KERNEL:-$(uname -r)}

# If DKMS is installed, use it: the module then gets rebuilt automatically
# for every kernel installed afterwards, instead of only working with one
# specific $KERNEL. Set USE_DKMS=no to force the plain, single-kernel build
# even when DKMS is present.
if [ -z "${USE_DKMS}" ] && command -v dkms > /dev/null 2>&1; then
  USE_DKMS=yes
fi
USE_DKMS=${USE_DKMS:-no}

if [ "$USE_DKMS" = "yes" ]; then
  PKGVER=$VERSION
else
  PKGVER=${VERSION}_$(echo $KERNEL | tr - _)
fi

if [ "$USE_DKMS" = "yes" ]; then
  # Source only, nothing compiled at packaging time -- dkms does the actual
  # compiling later, on whatever architecture the target machine is.
  ARCH=noarch
elif [ -z "$ARCH" ]; then
  case "$( uname -m )" in
    i?86) ARCH=i586 ;;
    arm*) ARCH=arm ;;
       *) ARCH=$( uname -m ) ;;
  esac
fi

# If the variable PRINT_PACKAGE_NAME is set, then this script will report what
# the name of the created package would be, and then exit. This information
# could be useful to other scripts.
if [ ! -z "${PRINT_PACKAGE_NAME}" ]; then
  echo "$PRGNAM-$PKGVER-$ARCH-$BUILD$TAG.$PKGTYPE"
  exit 0
fi

TMP=${TMP:-/tmp/SBo}
PKG=$TMP/package-$PRGNAM
OUTPUT=${OUTPUT:-/tmp}

if [ "$USE_DKMS" != "yes" ] && [ ! -d /lib/modules/$KERNEL/build ]; then
  echo "Kernel build tree /lib/modules/$KERNEL/build not found."
  echo "Install the kernel headers/source for $KERNEL (or set KERNEL= to"
  echo "the kernel version you want to build against) and try again."
  exit 1
fi

set -e

rm -rf $PKG
mkdir -p $TMP $PKG $OUTPUT
cd $TMP
rm -rf $PRGNAM-v$VERSION
tar xvf $CWD/$PRGNAM-v$VERSION.tar.gz
cd $PRGNAM-v$VERSION
chown -R root:root .
find -L . \
 \( -perm 777 -o -perm 775 -o -perm 750 -o -perm 711 -o -perm 555 \
  -o -perm 511 \) -exec chmod 755 {} \; -o \
 \( -perm 666 -o -perm 664 -o -perm 640 -o -perm 600 -o -perm 444 \
  -o -perm 440 -o -perm 400 \) -exec chmod 644 {} \;

# Backport of upstream fixes (not yet in a tagged release) needed to build
# against Linux 6.11+, including current Slackware kernels. Self-guarded by
# LINUX_VERSION_CODE checks, so safe to apply unconditionally.
patch -p1 < $CWD/ddcci-kernel-6.11-compat.patch
cp $CWD/fix-strncpy.sh $CWD/ddcci-sysfs-emit.patch .
chmod 755 fix-strncpy.sh

mkdir -p $PKG/usr/doc/$PRGNAM-$PKGVER
cp -a LICENSE README.md $PKG/usr/doc/$PRGNAM-$PKGVER
cat $CWD/$PRGNAM.SlackBuild > $PKG/usr/doc/$PRGNAM-$PKGVER/$PRGNAM.SlackBuild

mkdir -p $PKG/install
cat $CWD/slack-desc > $PKG/install/slack-desc

if [ "$USE_DKMS" = "yes" ]; then
  # Ship source only; dkms.conf's PRE_BUILD runs fix-strncpy.sh against
  # whatever kernel DKMS is building for, each time it builds.
  SRCDIR=$PKG/usr/src/ddcci-$VERSION
  mkdir -p $SRCDIR
  cp -a Makefile Makefile.dkms LICENSE README.md fix-strncpy.sh \
    ddcci-sysfs-emit.patch ddcci ddcci-backlight include $SRCDIR
  sed "s/@VERSION@/$VERSION/" $CWD/dkms.conf > $SRCDIR/dkms.conf

  sed "s/@VERSION@/$VERSION/" $CWD/doinst-dkms.sh > $PKG/install/doinst.sh
  sed "s/@VERSION@/$VERSION/" $CWD/douninst-dkms.sh > $PKG/install/douninst.sh
else
  ./fix-strncpy.sh $KERNEL

  make KVER=$KERNEL

  mkdir -p $PKG/lib/modules/$KERNEL/extra
  install -m 0644 ddcci/ddcci.ko ddcci-backlight/ddcci-backlight.ko \
    $PKG/lib/modules/$KERNEL/extra/

  find $PKG -print0 | xargs -0 file | grep -e "executable" -e "shared object" | grep ELF \
    | cut -f 1 -d : | xargs strip --strip-unneeded 2> /dev/null || true

  sed "s/@KERNEL@/$KERNEL/" $CWD/doinst.sh > $PKG/install/doinst.sh
fi

cd $PKG
/sbin/makepkg -l y -c n $OUTPUT/$PRGNAM-$PKGVER-$ARCH-$BUILD$TAG.$PKGTYPE