first stab at android.

android/src/clojure/advent/android.clj

@@ -0,0 +1,22 @@
+(ns advent.android
+  (:import [com.android.billingclient.api PurchasesUpdatedListener PurchaseHistoryResponseListener Purchase$PurchasesResult])
+  (:require [clojure.core.async :as a]))
+
+(def purchase-chan (a/chan))
+
+(def listener
+  (reify PurchasesUpdatedListener
+    (onPurchasesUpdated [this response-code purchases]
+      (println response-code purchases)
+      (let [result (and purchases (> (.size purchases) 0))]
+        (reset! @(resolve 'advent.core/has-purchased?) (if result true false))
+        (a/go (a/>! purchase-chan (if result true false)))))) )
+
+(def history-listener
+  (reify PurchaseHistoryResponseListener
+    (onPurchaseHistoryResponse [this purchases-result]
+      (println "got history")
+      (let [result (and purchases-result (.getPurchasesList purchases-result) (> (.size (.getPurchasesList purchases-result)) 0))]
+        (reset! @(resolve 'advent.core/has-purchased?) (if result true false))
+        (a/go (a/>! purchase-chan (if result true false)))))) )
+