#!/bin/bash

set -e

# This works only on Linux-{x86_64,s390x,aarch64,ppc64le} and macOS-x86_64.
case "$$(uname -s)-$$(uname -m)" in
Linux-x86_64|Linux-s390x|Linux-aarch64|Linux-ppc64le|Darwin-x86_64)
  ;;
*)
  echo "ERROR: wee8 is currently supported only on Linux-{x86_64,s390x,aarch64,ppc64le} and macOS-x86_64." >&2
  exit 1
esac

# Bazel magic.
ROOT=$$(dirname $(rootpath wee8/BUILD.gn))/..
pushd $$ROOT/wee8

# Clean after previous build.
rm -rf out/wee8

# Export compiler configuration.
export CXXFLAGS="$${CXXFLAGS-} -Wno-sign-compare -Wno-deprecated-copy -Wno-unknown-warning-option -Wno-range-loop-analysis -Wno-shorten-64-to-32"
if [[ ( `uname` == "Darwin" && $${CXX-} == "" ) || $${CXX-} == *"clang"* ]]; then
  export IS_CLANG=true
  export CC=$${CC:-clang}
  export CXX=$${CXX:-clang++}
  export CXXFLAGS="$${CXXFLAGS} -Wno-implicit-int-float-conversion -Wno-builtin-assume-aligned-alignment -Wno-final-dtor-non-final-class"
else
  export IS_CLANG=false
  export CC=$${CC:-gcc}
  export CXX=$${CXX:-g++}
fi

export AR=$${AR:-ar}
export NM=$${NM:-nm}

# Hook sanitizers.
if [[ $${ENVOY_ASAN-} == "1" ]]; then
  WEE8_BUILD_ARGS+=" is_asan=true"
  WEE8_BUILD_ARGS+=" is_lsan=true"
fi
if [[ $${ENVOY_UBSAN_VPTR-} == "1" ]]; then
  WEE8_BUILD_ARGS+=" is_ubsan=true"
  WEE8_BUILD_ARGS+=" is_ubsan_vptr=true"
fi
if [[ $${ENVOY_MSAN-} == "1" ]]; then
  WEE8_BUILD_ARGS+=" is_msan=true"
  export LDFLAGS="$${LDFLAGS} -L/opt/libcxx_msan/lib -Wl,-rpath,/opt/libcxx_msan/lib"
fi
if [[ $${ENVOY_TSAN-} == "1" ]]; then
  WEE8_BUILD_ARGS+=" is_tsan=true"
fi

# Debug/release build.
if [[ $(COMPILATION_MODE) == "dbg" && $${ENVOY_UBSAN_VPTR-} != "1" && $${ENVOY_MSAN-} != "1" && $${ENVOY_TSAN-} != "1" ]]; then
  WEE8_BUILD_ARGS+=" is_debug=true"
  WEE8_BUILD_ARGS+=" v8_symbol_level=2"
  WEE8_BUILD_ARGS+=" v8_optimized_debug=false"
else
  WEE8_BUILD_ARGS+=" is_debug=false"
  WEE8_BUILD_ARGS+=" v8_symbol_level=1"
  WEE8_BUILD_ARGS+=" v8_enable_handle_zapping=false"
fi

# Clang or not Clang, that is the question.
WEE8_BUILD_ARGS+=" is_clang=$$IS_CLANG"
# Hack to disable bleeding-edge compiler flags.
WEE8_BUILD_ARGS+=" use_xcode_clang=true"
# Use local toolchain.
WEE8_BUILD_ARGS+=" custom_toolchain=\"//build/toolchain/linux/unbundle:default\""
# Use local stdlibc++ / libc++.
WEE8_BUILD_ARGS+=" use_custom_libcxx=false"
# Use local sysroot.
WEE8_BUILD_ARGS+=" use_sysroot=false"
# Disable unused GLib2 dependency.
WEE8_BUILD_ARGS+=" use_glib=false"
# Expose debug symbols.
WEE8_BUILD_ARGS+=" v8_expose_symbols=true"
# Build monolithic library.
WEE8_BUILD_ARGS+=" is_component_build=false"
WEE8_BUILD_ARGS+=" v8_enable_i18n_support=false"
WEE8_BUILD_ARGS+=" v8_enable_gdbjit=false"
WEE8_BUILD_ARGS+=" v8_use_external_startup_data=false"
# Disable read-only heap, since it's leaky and HEAPCHECK complains about it.
# TODO(PiotrSikora): remove when fixed upstream.
WEE8_BUILD_ARGS+=" v8_enable_shared_ro_heap=false"
# Support Arm64
if [[ `uname -m` == "aarch64" ]]; then
  WEE8_BUILD_ARGS+=" target_cpu=\"arm64\""
fi
# Support ppc64
# Only tests with gn 5da62d5
if [[ `uname -m` == "ppc64le" ]]; then
  WEE8_BUILD_ARGS+=" target_cpu=\"ppc64\""
fi

# Build wee8.
if [[ -f /etc/centos-release ]] && [[ $$(cat /etc/centos-release) =~ "CentOS Linux release 7" ]] && [[ -x "$$(command -v gn)" ]]; then
  # Using system default gn tools
  # This is done only for CentOS 7, as it has an old version of GLIBC which is otherwise incompatible
  gn=$$(command -v gn)
elif [[ "$$(uname -s)" == "Darwin" ]]; then
  gn=buildtools/mac/gn
elif [[ "$$(uname -s)-$$(uname -m)" == "Linux-x86_64" ]]; then
  gn=buildtools/linux64/gn
else
  # Using system default gn tools
  gn=$$(command -v gn)
fi

if [[ "$$(uname -s)" == "Darwin" ]]; then
  ninja=third_party/depot_tools/ninja
elif [[ "$$(uname -s)-$$(uname -m)" == "Linux-x86_64" ]]; then
  ninja=third_party/depot_tools/ninja
else
  # Using system default ninja tools
  ninja=$$(command -v ninja)
fi

"$$gn" gen out/wee8 --args="$$WEE8_BUILD_ARGS"
"$$ninja" -C out/wee8 wee8

# Move compiled library to the expected destinations.
popd
mv $$ROOT/wee8/out/wee8/obj/libwee8.a $(execpath libwee8.a)