first commit

src/packagist.ts

@@ -0,0 +1,37 @@
+import * as cv from 'compare-versions';
+import * as fetch from './fetch';
+
+type RS = Record<string, string>;
+type RSRS = Record<string, RS>;
+
+export async function search(
+  package_name: string,
+  php_version: string
+): Promise<string | null> {
+  const response = await fetch.fetch(
+    `https://repo.packagist.org/p2/${package_name}.json`
+  );
+  if (response.error || response.data === '[]') {
+    return null;
+  }
+
+  const data = JSON.parse(response['data']);
+  if (data && data.packages) {
+    const versions = data.packages[package_name];
+    versions.sort((a: RS, b: RS) => cv.compareVersions(b.version, a.version));
+
+    const result = versions.find((versionData: RSRS) => {
+      if (versionData?.require?.php) {
+        return versionData?.require?.php
+          .split('|')
+          .some(
+            require => require && cv.satisfies(php_version + '.0', require)
+          );
+      }
+      return false;
+    });
+
+    return result ? result.version : null;
+  }
+  return null;
+}