Distribute shell/batch scripts on macOS/Window

Problem: I've quickly learned that cross-compiling is a major headache
and that C programming lacks both rainbows and butterflies. It seems
that my executable only works on Linux, but probably not macOS or
Windows.

Solution: Use shell scripts on macOS, which work when you double-click
them, and batch scripts on Windows, which I *think* work when you
double-click them. I haven't tested this on a macOS device yet, but I
tested the previous shell script on macOS and it seemed to work fine.
Unless I've done something silly, this should work on macOS, but the
Windows batch script is just me writing code from memory and probably
doesn't work correcly. I'll probably beg @SoapDog to help me fix it.

scripts/build.sh

@@ -2,39 +2,45 @@
 
 set -ex
 
-
 BASEDIR="$(dirname "$0")"
 
 cd "$BASEDIR/.."
 
 TARGET_VERSION="12.16.1"
-TARGET_PLATFORM="$1"
-TARGET_ARCH="$2"
-
-echo "Target version: $TARGET_VERSION"
-echo "Target platform: $TARGET_PLATFORM"
-echo "Target arch: $TARGET_ARCH"
-
-if [ "$TARGET_ARCH" == "x64" ]; then
-	GCC_ARCH="x86-64"
-else
-	echo "Unsupported architecture: $TARGET_ARCH"
-	exit 1
-fi
 
 git clean -fdx
 
 mkdir -p vendor
 cd vendor
 
-TARGET="node-v$TARGET_VERSION-$TARGET_PLATFORM-$TARGET_ARCH"
-TARBALL="$TARGET.tar.gz"
-URL="https://nodejs.org/dist/v$TARGET_VERSION/$TARBALL"
-TARGET_NODE="$TARGET/bin/node"
+get_tgz () {
+  TARGET_PLATFORM="$1"
+  TARGET="node-v$TARGET_VERSION-$TARGET_PLATFORM-x64"
+  ARCHIVE="$TARGET.tar.gz"
+  URL="https://nodejs.org/dist/v$TARGET_VERSION/$ARCHIVE"
+  TARGET_NODE="$TARGET/bin/node"
+
+  wget "$URL"
+  tar -xvf "$ARCHIVE" "$TARGET_NODE"
+  rm -rf "$ARCHIVE"
+}
+
+get_zip () {
+  TARGET_PLATFORM="$1"
+  TARGET="node-v$TARGET_VERSION-$TARGET_PLATFORM-x64"
+  ARCHIVE="$TARGET.zip"
+  URL="https://nodejs.org/dist/v$TARGET_VERSION/$ARCHIVE"
+  TARGET_NODE="$TARGET/node.exe"
+
+  wget "$URL"
+  unzip "$ARCHIVE" "$TARGET_NODE"
+  rm -rf "$ARCHIVE"
+}
+
+get_tgz darwin
+get_tgz linux
+get_zip win
 
-wget "$URL"
-tar -xvf "$TARBALL" "$TARGET_NODE"
-rm -rf "$TARBALL"
 cd ..
 
 # Avoid building anything from source.
@@ -42,19 +48,31 @@ npm ci --only=prod --ignore-scripts --no-audit --no-fund
 # More trouble than it's worth :)
 rm -rf ./node_modules/sharp
 
-BINARY_NAME="oasis"
+# Darwin (shell script)
+cat << EOF > oasis-darwin-x64
+#!/bin/sh
+exec vendor/node-v$TARGET_VERSION-darwin-x64/bin/node src "\$@"
+EOF
+chmod +x oasis-darwin-x64
 
-VENDOR_NODE="vendor/$TARGET_NODE"
+# Linux (ELF executable)
+clang scripts/oasis.c  -Wall -g -no-pie -o "oasis-linux-x64" --target=x86_64-linux-unknown -D "NODE=\"vendor/node-v$TARGET_VERSION-linux-x64/bin/node\""
+chmod +x oasis-linux-x64
 
-gcc scripts/oasis.c -Wall -g -no-pie -o "$BINARY_NAME" -march="$GCC_ARCH" -D "NODE=\"$VENDOR_NODE\""
+# Windows (batch file)
+cat << EOF > oasis-win-x64.bat
+vendor\\node-v$TARGET_VERSION-darwin-x64\\bin\\node src "\$@"
+EOF
 
-chmod +x "$BINARY_NAME"
+chmod +x oasis-win-x64.bat
 
 # I think if the zip already exists it's adding files to the existing archive?
-ZIP_PATH="/tmp/oasis-$TARGET_PLATFORM-$TARGET_ARCH.zip"
+ZIP_PATH="/tmp/oasis-x64.zip"
 
 rm -f "$ZIP_PATH"
 zip -r "$ZIP_PATH" . -x ".git/**"
 
-rm -f oasis
+rm -f oasis-darwin-x64
+rm -f oasis-linux-x64
+rm -f oasis-win-x64.bat
 rm -rf vendor