add preinstall check

npm/icloudpd/package.json

@@ -8,6 +8,9 @@
   "bin": {
     "icloudpd": "bin/icloudpd.js"
   },
+  "scripts": {
+    "preinstall": "node preinstall.js"
+  },
   "repository": {
     "type": "git",
     "url": "git+https://github.com/icloud_photos_downloader/icloud_photos_downloader.git"

npm/icloudpd/preinstall.js

@@ -0,0 +1,40 @@
+#!/usr/bin/env node
+"use strict";
+var os = require("os");
+var fs = require("fs");
+var platformKey = `${process.platform} ${os.arch()} ${os.endianness()}`;
+var knownPlatforms = {
+    "linux x64 LE": {
+        "pkgName": "@icloudpd/linux-x64",
+        "subPath": "bin/icloudpd" 
+    },
+    "linux ia32 LE": {
+        "pkgName": "@icloudpd/linux-ia32",
+        "subPath": "bin/icloudpd" 
+    },
+    "linux arm64 LE": {
+        "pkgName": "@icloudpd/linux-arm64",
+        "subPath": "bin/icloudpd" 
+    },
+    "linux arm LE": {
+        "pkgName": "@icloudpd/linux-arm",
+        "subPath": "bin/icloudpd" 
+    },
+    "darwin x64 LE": {
+        "pkgName": "@icloudpd/darwin-x64",
+        "subPath": "bin/icloudpd" 
+    },
+    "darwin arm64 LE": {
+        "pkgName": "@icloudpd/darwin-arm64",
+        "subPath": "bin/icloudpd" 
+    },
+    "win32 x64 LE": {
+        "pkgName": "@icloudpd/win32-x64",
+        "subPath": "bin/icloudpd.exe" 
+    }
+};
+if (platformKey in knownPlatforms) {
+    // all good to proceed
+} else {
+    throw new Error(`Unsupported platform: '${platformKey}'`);
+}