badge(homebrew): add cask version & download analytics support (#378)

* Add homebrew cask support

* Add homebrew download badges

api/homebrew.ts

@@ -1,25 +1,52 @@
 import got from '../libs/got'
-import { version, versionColor } from '../libs/utils'
+import { millify, version, versionColor } from '../libs/utils'
 import { createBadgenHandler, PathArgs } from '../libs/create-badgen-handler'
 
 export default createBadgenHandler({
   title: 'Homebrew',
   examples: {
     '/homebrew/v/fish': 'version',
-    '/homebrew/v/cake': 'version'
+    '/homebrew/v/cake': 'version',
+    '/homebrew/dm/fish': 'monthly downloads',
+    '/homebrew/dy/fish': 'yearly downloads',
+    '/homebrew/cask/v/atom': 'version',
+    '/homebrew/cask/v/whichspace': 'version'
+    // NOTE: cask analytics are broken
+    // '/homebrew/cask/dm/atom': 'monthly downloads',
+    // '/homebrew/cask/dy/atom': 'yearly downloads'
   },
   handlers: {
-    '/homebrew/v/:pkg': handler
+    '/homebrew/:topic<v|dm|dy>/:pkg': handler,
+    '/homebrew/:type<formula|cask>/:topic<v|dm|dy>/:pkg': handler
   }
 })
 
-async function handler ({ pkg }: PathArgs) {
-  const endpoint = `https://formulae.brew.sh/api/formula/${pkg}.json`
-  const { versions } = await got(endpoint).json<any>()
+async function handler ({ type = 'formula', topic, pkg }: PathArgs) {
+  const endpoint = `https://formulae.brew.sh/api/${type}/${pkg}.json`
+  const {
+    analytics,
+    versions,
+    version:ver = versions.stable
+  } = await got(endpoint).json<any>()
 
-  return {
-    subject: 'homebrew',
-    status: version(versions.stable),
-    color: versionColor(versions.stable)
+  switch (topic) {
+    case 'v':
+      return {
+        subject: type === 'cask' ? 'homebrew cask' : 'homebrew',
+        status: version(ver),
+        color: versionColor(ver)
+      }
+    case 'dm':
+      return {
+        subject: 'downloads',
+        status: millify(analytics.install['30d'][pkg]) + '/month',
+        color: 'green'
+      }
+    case 'dy':
+      return {
+        subject: 'downloads',
+        status: millify(analytics.install['365d'][pkg]) + '/year',
+        color: 'green'
+      }
   }
 }