Fix legacy WebView same-origin URL routing

app/src/main/kotlin/io/homeassistant/companion/android/webview/WebViewActivity.kt

@@ -653,9 +653,12 @@ class WebViewActivity :
                                     startActivity(intent)
                                 }
                                 return true
-                            } else if (!webView.url.toString().contains(it)) {
+                            }
+
+                            val targetUrl = it.toUri()
+                            if (shouldOpenInExternalBrowser(currentUrl = webView.url, targetUrl = targetUrl)) {
                                 Timber.d("Launching browser")
-                                val browserIntent = Intent(Intent.ACTION_VIEW, it.toUri())
+                                val browserIntent = Intent(Intent.ACTION_VIEW, targetUrl)
                                 startActivity(browserIntent)
                                 return true
                             } else {

app/src/main/kotlin/io/homeassistant/companion/android/webview/WebViewUrlOverride.kt

@@ -0,0 +1,15 @@
+package io.homeassistant.companion.android.webview
+
+import android.net.Uri
+import io.homeassistant.companion.android.util.hasSameOrigin
+
+internal fun shouldOpenInExternalBrowser(currentUrl: String?, targetUrl: Uri): Boolean {
+    if (!targetUrl.isHttpOrHttpsWithHost()) return true
+
+    return !targetUrl.hasSameOrigin(currentUrl)
+}
+
+private fun Uri.isHttpOrHttpsWithHost(): Boolean {
+    return host != null &&
+        (scheme.equals("http", ignoreCase = true) || scheme.equals("https", ignoreCase = true))
+}

app/src/test/kotlin/io/homeassistant/companion/android/webview/WebViewUrlOverrideTest.kt

@@ -0,0 +1,87 @@
+package io.homeassistant.companion.android.webview
+
+import android.net.Uri
+import dagger.hilt.android.testing.HiltTestApplication
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.RobolectricTestRunner
+import org.robolectric.annotation.Config
+
+@RunWith(RobolectricTestRunner::class)
+@Config(application = HiltTestApplication::class)
+class WebViewUrlOverrideTest {
+
+    @Test
+    fun `Given same origin URL with different path then WebView should handle it`() {
+        val targetUrl = Uri.parse("http://homeassistant.local:8123/lovelace/default")
+
+        val shouldOpen = shouldOpenInExternalBrowser(
+            currentUrl = "http://homeassistant.local:8123/",
+            targetUrl = targetUrl,
+        )
+
+        assertFalse(shouldOpen)
+    }
+
+    @Test
+    fun `Given different origin URL then external browser should handle it`() {
+        val targetUrl = Uri.parse("https://www.home-assistant.io/docs")
+
+        val shouldOpen = shouldOpenInExternalBrowser(
+            currentUrl = "http://homeassistant.local:8123/",
+            targetUrl = targetUrl,
+        )
+
+        assertTrue(shouldOpen)
+    }
+
+    @Test
+    fun `Given missing current URL then external browser should handle it`() {
+        val targetUrl = Uri.parse("http://homeassistant.local:8123/lovelace/default")
+
+        val shouldOpen = shouldOpenInExternalBrowser(
+            currentUrl = null,
+            targetUrl = targetUrl,
+        )
+
+        assertTrue(shouldOpen)
+    }
+
+    @Test
+    fun `Given mail URL then external browser should handle it`() {
+        val targetUrl = Uri.parse("mailto:user@example.com")
+
+        val shouldOpen = shouldOpenInExternalBrowser(
+            currentUrl = "http://homeassistant.local:8123/",
+            targetUrl = targetUrl,
+        )
+
+        assertTrue(shouldOpen)
+    }
+
+    @Test
+    fun `Given telephone URL then external browser should handle it`() {
+        val targetUrl = Uri.parse("tel:+15555555555")
+
+        val shouldOpen = shouldOpenInExternalBrowser(
+            currentUrl = "http://homeassistant.local:8123/",
+            targetUrl = targetUrl,
+        )
+
+        assertTrue(shouldOpen)
+    }
+
+    @Test
+    fun `Given relative URL then external browser should handle it`() {
+        val targetUrl = Uri.parse("/lovelace/default")
+
+        val shouldOpen = shouldOpenInExternalBrowser(
+            currentUrl = "http://homeassistant.local:8123/",
+            targetUrl = targetUrl,
+        )
+
+        assertTrue(shouldOpen)
+    }
+}