Make it so that canDownload() returns a reason instead of a boolean.

Author: io7m

org.librarysimplified.http.api/src/main/java/org/librarysimplified/http/api/LSHTTPNetworkAccessReadableType.kt

@@ -1,24 +1,50 @@
 package org.librarysimplified.http.api
 
+import org.librarysimplified.http.api.LSHTTPNetworkAccessReadableType.LSHTTPNetworkAvailability.NETWORK_AVAILABLE
+import org.librarysimplified.http.api.LSHTTPNetworkAccessReadableType.LSHTTPNetworkAvailability.NETWORK_NOT_PERMITTED
+import org.librarysimplified.http.api.LSHTTPNetworkAccessReadableType.LSHTTPNetworkAvailability.NETWORK_UNAVAILABLE
+
 /**
  * An observable interface that indicates the availability of different network types.
  */
 
 interface LSHTTPNetworkAccessReadableType :
   LSHTTPNetworkAvailabilityReadableType,
   LSHTTPNetworkPolicyReadableType {
+
+  /**
+   * The reason that downloads may or may not be available.
+   */
+
+  enum class LSHTTPNetworkAvailability {
+    NETWORK_UNAVAILABLE,
+    NETWORK_AVAILABLE,
+    NETWORK_NOT_PERMITTED,
+  }
+
   /**
    * Determine if performing a download should be allowed given the current network availability
    * and permissions.
    */
 
-  fun canDownload(): Boolean {
-    if (this.wifiAvailable.get() && this.wifiPermitted.get()) {
-      return true
+  fun canDownload(): LSHTTPNetworkAvailability {
+    val wifiAvailable = this.wifiAvailable.get()
+    val cellAvailable = this.cellularAvailable.get()
+    val wifiPermitted = this.wifiPermitted.get()
+    val cellPermitted = this.cellularPermitted.get()
+
+    if (!wifiAvailable && !cellAvailable) {
+      return NETWORK_UNAVAILABLE
+    }
+
+    if (wifiAvailable && wifiPermitted) {
+      return NETWORK_AVAILABLE
     }
-    if (this.cellularAvailable.get() && this.cellularPermitted.get()) {
-      return true
+
+    if (cellAvailable && cellPermitted) {
+      return NETWORK_AVAILABLE
     }
-    return false
+
+    return NETWORK_NOT_PERMITTED
   }
 }

org.librarysimplified.http.tests/src/test/java/org/librarysimplified/http/tests/LSHTTPNetworkAccessTest.kt

@@ -3,6 +3,9 @@ package org.librarysimplified.http.tests
 import org.junit.jupiter.api.Assertions
 import org.junit.jupiter.api.Test
 import org.librarysimplified.http.api.LSHTTPNetworkAccess
+import org.librarysimplified.http.api.LSHTTPNetworkAccessReadableType.LSHTTPNetworkAvailability.NETWORK_AVAILABLE
+import org.librarysimplified.http.api.LSHTTPNetworkAccessReadableType.LSHTTPNetworkAvailability.NETWORK_NOT_PERMITTED
+import org.librarysimplified.http.api.LSHTTPNetworkAccessReadableType.LSHTTPNetworkAvailability.NETWORK_UNAVAILABLE
 
 class LSHTTPNetworkAccessTest {
 
@@ -13,7 +16,7 @@ class LSHTTPNetworkAccessTest {
     LSHTTPNetworkAccess.setWIFIAvailable(true)
     LSHTTPNetworkAccess.setWIFIPermitted(true)
 
-    Assertions.assertTrue(LSHTTPNetworkAccess.canDownload())
+    Assertions.assertEquals(NETWORK_AVAILABLE, LSHTTPNetworkAccess.canDownload())
   }
 
   @Test
@@ -23,7 +26,7 @@ class LSHTTPNetworkAccessTest {
     LSHTTPNetworkAccess.setWIFIAvailable(true)
     LSHTTPNetworkAccess.setWIFIPermitted(true)
 
-    Assertions.assertTrue(LSHTTPNetworkAccess.canDownload())
+    Assertions.assertEquals(NETWORK_AVAILABLE, LSHTTPNetworkAccess.canDownload())
   }
 
   @Test
@@ -33,7 +36,7 @@ class LSHTTPNetworkAccessTest {
     LSHTTPNetworkAccess.setWIFIAvailable(false)
     LSHTTPNetworkAccess.setWIFIPermitted(false)
 
-    Assertions.assertTrue(LSHTTPNetworkAccess.canDownload())
+    Assertions.assertEquals(NETWORK_AVAILABLE, LSHTTPNetworkAccess.canDownload())
   }
 
   @Test
@@ -43,7 +46,7 @@ class LSHTTPNetworkAccessTest {
     LSHTTPNetworkAccess.setWIFIAvailable(true)
     LSHTTPNetworkAccess.setWIFIPermitted(false)
 
-    Assertions.assertFalse(LSHTTPNetworkAccess.canDownload())
+    Assertions.assertEquals(NETWORK_NOT_PERMITTED, LSHTTPNetworkAccess.canDownload())
   }
 
   @Test
@@ -53,6 +56,6 @@ class LSHTTPNetworkAccessTest {
     LSHTTPNetworkAccess.setWIFIAvailable(false)
     LSHTTPNetworkAccess.setWIFIPermitted(true)
 
-    Assertions.assertFalse(LSHTTPNetworkAccess.canDownload())
+    Assertions.assertEquals(NETWORK_UNAVAILABLE, LSHTTPNetworkAccess.canDownload())
   }
 }