NFC-50 Add unit tests for WebEidViewModel handleAuth() with base64 and JSON validation

Author: SanderKondratjevNortal

app/src/androidTest/kotlin/ee/ria/DigiDoc/viewmodel/WebEidViewModelTest.kt

@@ -0,0 +1,81 @@
+@file:Suppress("PackageName")
+
+package ee.ria.DigiDoc.viewmodel
+
+import android.net.Uri
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.test.runTest
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Before
+import org.junit.Test
+
+@OptIn(ExperimentalCoroutinesApi::class)
+class WebEidViewModelTest {
+
+    private lateinit var viewModel: WebEidViewModel
+
+    @Before
+    fun setUp() {
+        viewModel = WebEidViewModel()
+    }
+
+    @Test
+    fun handleAuth_validUri_setsAuthPayload() = runTest {
+        val json = """
+            {
+              "challenge": "abc123",
+              "login_uri": "https://example.com/auth/login",
+              "get_signing_certificate": true
+            }
+        """.trimIndent()
+
+        val encoded = java.util.Base64.getEncoder().encodeToString(json.toByteArray())
+        val uri = Uri.parse("web-eid-mobile://auth#$encoded")
+
+        viewModel.handleAuth(uri)
+
+        val result = viewModel.authPayload.value
+        assertEquals("abc123", result?.challenge)
+        assertEquals("https://example.com/auth/login", result?.loginUri)
+        assertEquals(true, result?.getSigningCertificate)
+    }
+
+    @Test
+    fun handleAuth_missingFragment_setsNullPayload() = runTest {
+        val uri = Uri.parse("web-eid-mobile://auth")
+
+        viewModel.handleAuth(uri)
+
+        assertNull(viewModel.authPayload.value)
+    }
+
+    @Test
+    fun handleAuth_invalidBase64_setsNullPayload() = runTest {
+        val uri = Uri.parse("web-eid-mobile://auth#invalid-base64!!")
+
+        viewModel.handleAuth(uri)
+
+        assertNull(viewModel.authPayload.value)
+    }
+
+    @Test
+    fun handleAuth_missingOptionalField_defaultsToFalse() = runTest {
+        val json = """
+            {
+              "challenge": "xyz456",
+              "login_uri": "https://rp.example.com/login"
+            }
+        """.trimIndent()
+
+        val encoded = java.util.Base64.getEncoder().encodeToString(json.toByteArray())
+        val uri = Uri.parse("web-eid-mobile://auth#$encoded")
+
+        viewModel.handleAuth(uri)
+
+        val result = viewModel.authPayload.value
+        assertEquals("xyz456", result?.challenge)
+        assertEquals("https://rp.example.com/login", result?.loginUri)
+        assertEquals(false, result?.getSigningCertificate)
+    }
+}