#!/bin/bash

# Copyright 2017  Andrew Clemons, Wellington, New Zealand
# Copyright 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2025  Patrick J. Volkerding, Sebeka, Minnesota, USA
# Copyright 2017  Stuart Winter
# 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)

PKGNAM=rust-wasm
SRCNAM="rustc"
VERSION=${VERSION:-1.88.0}
BUILD=${BUILD:-1}

# Set this to YES to build with the system LLVM, or NO to use the bundled LLVM.
SYSTEM_LLVM=${SYSTEM_LLVM:-NO}

# Bootstrap variables (might not be kept updated for latest Rust):
RSTAGE0_VERSION=${RSTAGE0_VERSION:-1.87.0}
RSTAGE0_DIR=${RSTAGE0_DIR:-2025-05-15}
CSTAGE0_VERSION=${CSTAGE0_VERSION:-1.87.0}
CSTAGE0_DIR=${CSTAGE0_DIR:-$RSTAGE0_DIR}

# Automatically determine the architecture we're building on:
MARCH=$( uname -m )
if [ -z "$ARCH" ]; then
  case "$MARCH" in
    i?86)    export ARCH=i686 ;;
    armv7hl) export ARCH=$MARCH ;;
    arm*)    export ARCH=arm ;;
    # Unless $ARCH is already set, use uname -m for all other archs:
    *)       export ARCH=$MARCH ;;
  esac
fi
unset MARCH

# For compiling i686 under an x86_64 kernel:
if [ "$(uname -m)" = "x86_64" -a "$(file -L /usr/bin/gcc | grep 386 | grep 32-bit)" != "" ]; then
  ARCH=i686
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 "${PRINT_PACKAGE_NAME}" ]; then
  echo "$PKGNAM-$VERSION-$ARCH-$BUILD.txz"
  exit 0
fi

# If the bootstrap binaries are present, use those. Otherwise bootstrap from
# installed compiler.
if /bin/ls *-unknown-linux-gnu.tar.?z 1> /dev/null 2> /dev/null ; then
  LOCAL_BOOTSTRAP=no
else
  LOCAL_BOOTSTRAP=yes
fi

# https://forge.rust-lang.org/platform-support.html
# Bootstrapping ARCH:
if [ "$ARCH" = "i586" ]; then
  if [ "$LOCAL_BOOTSTRAP" = "yes" ] ; then
    if rustc -Vv | grep host | grep i586 > /dev/null ; then
      BARCH="$ARCH"
    else
      BARCH="i686"
      if case "$( uname -m )" in i586) true ;; *) false ;; esac ; then
        echo "rust must be bootstrapped from an i686 machine"
        exit 1
      fi
    fi
  else
    # i586 must be built on a i686 machine, since the bootstrap compiler is i686
    BARCH="i686"
    if case "$( uname -m )" in i586) true ;; *) false ;; esac ; then
      echo "rust must be bootstrapped from an i686 machine"
      exit 1
    fi
  fi
elif [ "$ARCH" = "armv7hl" ]; then
  BARCH="armv7"
else
  BARCH="$ARCH"
fi

TARCH="wasm32"

# Bootstrapping ABI:
if [ "$ARCH" = "armv7hl" ]; then
  BABI="gnueabihf"
else
  BABI="gnu"
fi

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

# Not needed, as the build will automatically use as many jobs as there are
# threads.
#NUMJOBS=${NUMJOBS:-" -j$(expr $(nproc) + 1) "}

if [ "$ARCH" = "i586" ]; then
  LIBDIRSUFFIX=""
elif [ "$ARCH" = "i686" ]; then
  LIBDIRSUFFIX=""
elif [ "$ARCH" = "x86_64" ]; then
  LIBDIRSUFFIX="64"
elif [ "$ARCH" = "armv7hl" ]; then
  LIBDIRSUFFIX=""
else
  LIBDIRSUFFIX=""
fi

rm -rf $PKG
mkdir -p $TMP $PKG $OUTPUT
cd $TMP
rm -rf $SRCNAM-$VERSION-src
echo "Extracting $CWD/$SRCNAM-$VERSION-src.tar.?z..."
tar xf $CWD/$SRCNAM-$VERSION-src.tar.?z || exit 1
cd $SRCNAM-$VERSION-src || exit 1

# Link with -lffi in case of using system LLVM:
if [ "${SYSTEM_LLVM}" = "YES" ]; then
  zcat $CWD/link_libffi.diff.gz | patch -p1 --verbose || exit 1
fi

# Use wasm-ld instead of rust-lld
zcat $CWD/0004-compiler-Use-wasm-ld-for-wasm-targets.patch.gz | patch -p1 --verbose || exit 1

if [ "$LOCAL_BOOTSTRAP" != "yes" ] ; then
  # rust requires bootstrapping with the previous rust version.
  # versions are defined in src/stage0.txt.
  mkdir -p build/cache/$RSTAGE0_DIR
  cp $CWD/rust-std-$RSTAGE0_VERSION-$BARCH-unknown-linux-gnu.tar.?z \
     $CWD/$SRCNAM-$RSTAGE0_VERSION-$BARCH-unknown-linux-gnu.tar.?z \
     build/cache/$RSTAGE0_DIR
  mkdir -p build/cache/$CSTAGE0_DIR
  cp $CWD/cargo-$CSTAGE0_VERSION-$BARCH-unknown-linux-gnu.tar.?z build/cache/$CSTAGE0_DIR
fi

# Build configuration:
cat << EOF > config.toml
# Avoid triggering "git --local" on non-git vendored sources:
profile = "dist"

[llvm]
ccache = "/usr/bin/ccache"
link-shared = true
clang = false
download-ci-llvm = false

[build]
build = "$BARCH-unknown-linux-$BABI"
host = ["$BARCH-unknown-linux-$BABI"]
target = ["$TARCH-unknown-unknown"]
tools = ["analysis"]
submodules = false
vendor = true
extended = false
docs = false

[install]
prefix = "/usr"
docdir = "doc/$PKGNAM-$VERSION"
libdir = "lib$LIBDIRSUFFIX"
mandir = "man"

[rust]
codegen-units = 0
channel = "stable"
rpath = false
codegen-tests = false

EOF

if [ "${SYSTEM_LLVM}" = "YES" ]; then
  cat << EOF >> config.toml
# Add this stuff to build with the system LLVM:
[target.x86_64-unknown-linux-gnu]
llvm-config = "/usr/bin/llvm-config"
sanitizers = false
profiler = false

[target.wasm32-unknown-unknown]
llvm-config = "/usr/bin/llvm-config"
sanitizers = false
profiler = false
EOF
else
  cat << EOF >> config.toml
# Add this stuff to build with rust's LLVM:
[target.wasm32-unknown-unknown]
cc = "/usr/bin/clang"
sanitizers = false
profiler = false
EOF
fi

if [ "$LOCAL_BOOTSTRAP" = "yes" ] ; then
  sed -i "s|^\(extended = true\)$|\1\nrustc = \"/usr/bin/rustc\"\ncargo = \"/usr/bin/cargo\"|" config.toml
fi

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 {} \+

export PKG_CONFIG_ALLOW_CROSS=1

# Build and install:
python3 ./x.py build || exit 1
DESTDIR=$PKG python3 x.py install || exit 1

# Don't overwrite files from main rust package
# TODO: Might be better to copy needed files by hand rather than clean up the install target
# ./x.py dist std might also help in that regard
rm -rf $PKG/usr/bin
rm -f $PKG/usr/lib$LIBDIRSUFFIX/*.so
rm -f $PKG/usr/lib$LIBDIRSUFFIX/libLLVM.so.*
rm -rf $PKG/usr/lib$LIBDIRSUFFIX/rustlib/{components,etc}
rm -f $PKG/usr/lib$LIBDIRSUFFIX/rustlib/{install.log,uninstall.sh,rust-installer-version}
rm -f $PKG/usr/lib$LIBDIRSUFFIX/rustlib/manifest*
rm -rf $PKG/usr/lib$LIBDIRSUFFIX/rustlib/$BARCH-unknown-linux-$BABI
rm -rf $PKG/usr/man

# Move bash completions to the system location:
if [ -d $PKG/etc/bash_completion.d ]; then
  mkdir -p $PKG/usr/share/bash-completion
  mv $PKG/etc/bash_completion.d $PKG/usr/share/bash-completion/completions
  rmdir $PKG/etc 2> /dev/null
fi

# Correct permissions on shared libraries:
find $PKG/usr/lib$LIBDIRSUFFIX -name "*.so" -exec chmod 755 "{}" \+

# Evidently there are a lot of duplicated libraries in this tree, so let's
# try to save some space:
( cd $PKG/usr/lib${LIBDIRSUFFIX}/rustlib/*-unknown-unknown/lib && for file in *.so ; do if cmp -s $file ../../../$file ; then ln -sf ../../../$file .; fi; done )

# Strip ELF objects:
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

# Get rid of possible .old files in these locations:
rm -f $PKG/usr/lib${LIBDIRSUFFIX}/*.old
rm -f $PKG/usr/bin/*.old

# Commented out (for now) since we disable rpaths in config.toml:
## Remove any compiled-in RPATHs:
#find $PKG -print0 | xargs -0 file | grep -e "executable" -e "shared object" | grep ELF \
#  | cut -f 1 -d : | while read elfobject ; do
#  patchelf --remove-rpath $elfobject || exit 1
#done

# Add some documentation:
mkdir -p $PKG/usr/doc/$PKGNAM-$VERSION
cp -a *.md COPYRIGHT* LICENSE* $PKG/usr/doc/$PKGNAM-$VERSION
# Include licenses from third party vendors:
mkdir $PKG/usr/doc/$PKGNAM-$VERSION/vendor
( cd vendor
  tar cf - $(find . -maxdepth 2 | grep -e README -e LICENSE -e COPYING -e CHANGELOG -e PERFORMANCE -e UPGRADE ) | ( cd $PKG/usr/doc/$PKGNAM-$VERSION/vendor ; tar xf - )
)

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

cd $PKG
/sbin/makepkg -l y -c n $OUTPUT/$PKGNAM-$VERSION-$ARCH-$BUILD.txz