#!/bin/bash
# $Id: gn.SlackBuild,v 1.1 2023/02/13 21:08:32 root Exp root $
# Copyright 2023  Eric Hameleers, Eindhoven, NL
# All rights reserved.
#
#   Permission to use, copy, modify, and distribute this software for
#   any purpose with or without fee is hereby granted, provided that
#   the above copyright notice and this permission notice appear in all
#   copies.
#
#   THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 AUTHORS AND COPYRIGHT HOLDERS AND THEIR
#   CONTRIBUTORS 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.
# -----------------------------------------------------------------------------
#
# Slackware SlackBuild script 
# ===========================
# By:          Eric Hameleers <alien@slackware.com>
# For:         gn
# Descr:       meta-build system that generates build files for Ninja
# URL:         https://gn.googlesource.com/gn/
# Build needs: 
# Needs:       
# Changelog:   
# 0.2077.5e19d2fb-1:
#              12/Feb/2023 by Eric Hameleers <alien@slackware.com>
#              * Initial build.
# 
# Run 'sh gn.SlackBuild' to build a Slackware package.
# The package (.t?z) and .txt file as well as build logs are created in /tmp .
# Install the package using 'installpkg' or 'upgradepkg --install-new'.
#
# -----------------------------------------------------------------------------

PRGNAM=gn
VERSION=${VERSION:-0.2077.5e19d2fb}
BUILD=${BUILD:-1}
NUMJOBS=${NUMJOBS:-" -j$(nproc) "}
TAG=${TAG:-alien}

# Versions of gn are closely tied to versions of chromium.
# So for any version of chromium, we determine the commit and
# related version string of the gn binary we should build.
# The gn base version is "0.<number of commits since initial commit>" ,
# The gn extra version is the first 8 digits of the git commit hash.
# The chromium version we want to base a gn package on:
CHROMIUM_VERSION=${CHROMIUM_VERSION:-"110.0.5481.77"}

DOCS="LICENSE docs/*"

# Where do we look for sources?
SRCDIR=$(cd $(dirname $0); pwd)

# Place to build (TMP) package (PKG) and output (OUTPUT) the program:
TMP=${TMP:-/tmp/build}
PKG=$TMP/package-$PRGNAM
OUTPUT=${OUTPUT:-/tmp}

# If you want automatic download to work, supply a URL for 'SRCURL' below:
SOURCE="$SRCDIR/${PRGNAM}-${VERSION}.tar.xz"
SRCURL=""

# Use the src_checkout() function if no downloadable tarball exists.
# Check out sources from GIT and create a tarball of them.
src_checkout() {
  # Param #1 : index in the SOURCE[] array.
  # Param #2 : full path to where SOURCE[$1] tarball should be created.
  # Determine the tarball extension:
  PEXT=$(echo "${2}" | sed -r -e 's/.*[^.].(tar.xz|tar.gz|tar.bz2|tgz).*/\1/')
  case "$PEXT" in
    "tar.xz") TARCOMP="J" ;;
    "tar.gz") TARCOMP="z" ;;
    "tgz") TARCOMP="z" ;;
    "tar.bz2") TARCOMP="j" ;;
    *) echo "Archive can only have extension 'tar.xz', '.tar.gz' '.tar.bz2' or '.tgz'" ; exit 1 ;;
  esac
  # Determine the directory name to create for the archive root:
  PBASE=$(basename ${2} .${PEXT})
  # Determine the directory where we create our checkout:
  CODIR=$(dirname ${2})
  case ${1} in
  0) GITURI="https://gn.googlesource.com/gn"
     BRANCH="master"
     COMMIT=$(echo $VERSION | cut -d. -f3)
     RETDIR=$(pwd)
     mkdir -p $CODIR/${PRGNAM}_temp_checkout_$$ \
       && cd $CODIR/${PRGNAM}_temp_checkout_$$
     mkdir ${PBASE} \
       && cd ${PBASE}
       echo "Checking out $BRANCH at commit $COMMIT from '$GITURI':"
       git clone ${GITURI} . \
         && git checkout $BRANCH \
         && git checkout $COMMIT \
       && chown -R root:root . \
       && cd .. \
       && tar -${TARCOMP}cf ${2} ${PBASE}
     cd $RETDIR
     rm -rf $CODIR/${PRGNAM}_temp_checkout_$$ || true
     ;;
  *) # Do nothing
     ;;
  esac
}

##
## --- with a little luck, you won't have to edit below this point --- ##
##

# Automatically determine the architecture we're building on:
if [ -z "$ARCH" ]; then
  case "$(uname -m)" in
    i?86) ARCH=i586 ;;
    arm*) readelf /usr/bin/file -A | egrep -q "Tag_CPU.*[4,5]" && ARCH=arm || ARCH=armv7hl ;;
    # Unless $ARCH is already set, use uname -m for all other archs:
    *) ARCH=$(uname -m) ;;
  esac
  export ARCH
fi
# Set CFLAGS/CXXFLAGS and LIBDIRSUFFIX:
case "$ARCH" in
  i?86)      SLKCFLAGS="-O2 -march=${ARCH} -mtune=i686"
             SLKLDFLAGS=""; LIBDIRSUFFIX=""
             ;;
  x86_64)    SLKCFLAGS="-O2 -fPIC"
             SLKLDFLAGS="-L/usr/lib64"; LIBDIRSUFFIX="64"
             ;;
  armv7hl)   SLKCFLAGS="-O2 -march=armv7-a -mfpu=vfpv3-d16"
             SLKLDFLAGS=""; LIBDIRSUFFIX=""
             ;;
  *)         SLKCFLAGS=${SLKCFLAGS:-"-O2"}
             SLKLDFLAGS=${SLKLDFLAGS:-""}; LIBDIRSUFFIX=${LIBDIRSUFFIX:-""}
             ;;
esac

case "$ARCH" in
    arm*)    TARGET=$ARCH-slackware-linux-gnueabi ;;
    *)       TARGET=$ARCH-slackware-linux ;;
esac

# Exit the script on errors:
set -e
trap 'echo "$0 FAILED at line ${LINENO}" | tee $OUTPUT/error-${PRGNAM}.log' ERR
# Catch unitialized variables:
set -u
P1=${1:-1}

# Save old umask and set to 0022:
_UMASK_=$(umask)
umask 0022

# Create working directories:
mkdir -p $OUTPUT          # place for the package to be saved
mkdir -p $TMP/tmp-$PRGNAM # location to build the source
mkdir -p $PKG             # place for the package to be built
rm -rf $PKG/*             # always erase old package's contents
rm -rf $TMP/tmp-$PRGNAM/* # remove the remnants of previous build
rm -rf $OUTPUT/{checkout,configure,make,install,error,makepkg,patch}-$PRGNAM.log
                          # remove old log files

# Source file availability:
if ! [ -f ${SOURCE} ]; then
  echo "Source '$(basename ${SOURCE})' not available yet..."
  # Check if the $SRCDIR is writable at all - if not, download to $OUTPUT
  [ -w "$SRCDIR" ] || SOURCE="$OUTPUT/$(basename ${SOURCE})"
  if [ -f ${SOURCE} ]; then echo "Ah, found it!"; continue; fi
  if ! [ "x${SRCURL}" == "x" ]; then
    echo "Will download file to $(dirname $SOURCE)"
    wget --no-check-certificate -nv -T 20 -O "${SOURCE}" "${SRCURL}" || true
    if [ $? -ne 0 -o ! -s "${SOURCE}" ]; then
      echo "Fail to download '$(basename ${SOURCE})'. Aborting the build."
      mv -f "${SOURCE}" "${SOURCE}".FAIL
      exit 1
    fi
  else
    # Try if we have a GIT download routine for ${SOURCE}
    echo "Will checkout sources to $(dirname $SOURCE)"
    src_checkout 0 "${SOURCE}" 2>&1 > $OUTPUT/checkout-$(basename ${SOURCE}).log
  fi
  if [ ! -f "${SOURCE}" -o ! -s "${SOURCE}" ]; then
    echo "File '$(basename ${SOURCE})' not available. Aborting the build."
    exit 1
  fi
fi

if [ "$P1" == "--download" ]; then
  echo "Download complete."
  echo "Check that the following match your expectations..."
  echo "   (wait for a bit since I will do a git checkout):"
  # In the Chromium source, determine which commit is being used for gn in DEPS:
  GN_GIT_COMMIT=$(wget -q -O - "https://chromium.googlesource.com/chromium/src/+/${CHROMIUM_VERSION}/DEPS?format=TEXT" |base64 -d |grep -Po "'gn_version': 'git_revision:\K[^']*")
  # Get gn sources and determine its version:
  TMP_GN_CO=$(mktemp -d -t gngit_XXXXXX)
  if [ ! -d ${TMP_GN_CO} ]; then
    echo "Could not create temp directory!" ; exit 1
  fi
  RETDIR=$(pwd)
  cd ${TMP_GN_CO}
    git clone https://gn.googlesource.com/gn gn 2>/dev/null
    cd gn
      git checkout ${GN_GIT_COMMIT} 2>/dev/null
      GN_VERSION="0.$(git rev-list --count initial-commit..).$(git rev-parse --short=8 HEAD)"
  cd $RETDIR
  rm -rf "${TMP_GN_CO}"
  echo ">> Current online version: ${GN_VERSION}"
  echo ">> GN SlackBuild version:  $VERSION"
  exit 0
fi

# --- PACKAGE BUILDING ---

echo "++"
echo "|| $PRGNAM-$VERSION"
echo "++"

cd $TMP/tmp-$PRGNAM
echo "Extracting the source archive(s) for $PRGNAM..."
tar -xvf ${SOURCE}
cd ${PRGNAM}-${VERSION}
chown -R root:root .
chmod -R u+w,go+r-w,a+rX-st .

echo Building ...
export LDFLAGS="$SLKLDFLAGS"
export CXXFLAGS="$SLKCFLAGS"
export CFLAGS="$SLKCFLAGS"

python3 build/gen.py --no-strip --allow-warnings \
  2>&1 | tee $OUTPUT/configure-${PRGNAM}.log

# Compile and install:
ninja -C out gn \
  2>&1 | tee $OUTPUT/make-${PRGNAM}.log
install -D -m0755 -t $PKG/usr/bin/ out/gn

# Add vim support files:
mkdir -p $PKG/usr/share/vim/vimfiles
cp -a misc/vim/{autoload,ftdetect,ftplugin,syntax} $PKG/usr/share/vim/vimfiles/

# Add emacs support files:
install -D -m0644 -t $PKG/usr/share/emacs/site-lisp misc/emacs/gn-mode.el

# Add documentation:
mkdir -p $PKG/usr/doc/$PRGNAM-$VERSION
cp -a $DOCS $PKG/usr/doc/$PRGNAM-$VERSION || true
cat $SRCDIR/$(basename $0) > $PKG/usr/doc/$PRGNAM-$VERSION/$PRGNAM.SlackBuild
chown -R root:root $PKG/usr/doc/$PRGNAM-$VERSION
find $PKG/usr/doc -type f -exec chmod 644 {} \;

# Compress the man page(s) if any:
if [ -d $PKG/usr/man ]; then
  find $PKG/usr/man -type f -name "*.?" -exec gzip -9f {} \;
  for i in $(find $PKG/usr/man -type l -name "*.?") ; do ln -s $( readlink $i ).gz $i.gz ; rm $i ; done
fi

# Strip binaries (if any):
find $PKG | xargs file | grep -e "executable" -e "shared object" | grep ELF \
  | cut -f 1 -d : | xargs strip --strip-unneeded 2> /dev/null || true

# Add a package description:
mkdir -p $PKG/install
cat $SRCDIR/slack-desc > $PKG/install/slack-desc

# Build the package:
cd $PKG
makepkg --linkadd y --chown n $OUTPUT/${PRGNAM}-${VERSION}-${ARCH}-${BUILD}${TAG}.${PKGTYPE:-txz} 2>&1 | tee $OUTPUT/makepkg-${PRGNAM}.log
cd $OUTPUT
md5sum ${PRGNAM}-${VERSION}-${ARCH}-${BUILD}${TAG}.${PKGTYPE:-txz} > ${PRGNAM}-${VERSION}-${ARCH}-${BUILD}${TAG}.${PKGTYPE:-txz}.md5
cd -
cat $PKG/install/slack-desc | grep "^${PRGNAM}" > $OUTPUT/${PRGNAM}-${VERSION}-${ARCH}-${BUILD}${TAG}.txt

# Restore the original umask:
umask ${_UMASK_}