#!/bin/bash
# Rebuild occt-import-js 0.0.23 with a 4 GiB WebAssembly heap.
#
# The only change from upstream is one link flag, -sMAXIMUM_MEMORY=4GB (see
# memory.patch). Upstream's toolchain is pinned: Emscripten 3.1.69 and the
# OpenCASCADE commit the 0.0.23 tag records as its submodule. That submodule's
# host, git.dev.opencascade.org, no longer resolves, so the same commit is
# fetched from the official GitHub mirror.
#
# Usage: ./build.sh <empty work directory>
set -euo pipefail
HERE=$(cd "$(dirname "$0")" && pwd)
WORK=${1:?usage: build.sh <work directory>}
mkdir -p "$WORK" && cd "$WORK"

[ -d venv ] || python3 -m venv venv
./venv/bin/pip -q install cmake==3.30.5 ninja==1.11.1.1
export PATH="$PWD/venv/bin:$PATH"

[ -d emsdk ] || git clone -q https://github.com/emscripten-core/emsdk.git
(cd emsdk && ./emsdk install 3.1.69 >/dev/null && ./emsdk activate 3.1.69 >/dev/null)
source emsdk/emsdk_env.sh >/dev/null

[ -d occt-import-js ] || git clone -q https://github.com/kovacsv/occt-import-js.git
cd occt-import-js
git checkout -q 0.0.23
PIN=$(git ls-tree HEAD occt | awk '{print $3}')
if [ ! -f occt/CMakeLists.txt ]; then
  rm -rf occt && git init -q occt
  git -C occt fetch -q --depth 1 https://github.com/Open-Cascade-SAS/OCCT.git "$PIN"
  git -C occt checkout -q FETCH_HEAD
fi
test "$(git -C occt rev-parse HEAD)" = "$PIN"

git apply --check "$HERE/memory.patch" 2>/dev/null && git apply "$HERE/memory.patch"
grep -q 'MAXIMUM_MEMORY=4GB' CMakeLists.txt

emcmake cmake -B build/wasm -G Ninja -DEMSCRIPTEN=1 -DCMAKE_BUILD_TYPE=Release .
cmake --build build/wasm -j "$(getconf _NPROCESSORS_ONLN)"

mkdir -p "$HERE/lib"
cp build/wasm/Release/occt-import-js.js build/wasm/Release/occt-import-js.wasm "$HERE/lib/"
cp occt/LICENSE_LGPL_21.txt "$HERE/lib/license.occt.txt"
cp LICENSE.md "$HERE/lib/license.occt-import-js.txt"
shasum -a 256 "$HERE/lib/occt-import-js.wasm"