Fix SettingsFontFamily when config is empty

Some device or when Compose preview, the font config is empty.

Use the default font family when the config is empty to fix.

Bug: 235727273
Test: Unit test
Test: Manual with Gallery App
Change-Id: Ifd9c5bbc3d446e5fdb5f393ad994c7545656ead6
diff --git a/packages/SettingsLib/Spa/spa/src/com/android/settingslib/spa/framework/theme/SettingsFontFamily.kt b/packages/SettingsLib/Spa/spa/src/com/android/settingslib/spa/framework/theme/SettingsFontFamily.kt
index 8e8805a..9479228 100644
--- a/packages/SettingsLib/Spa/spa/src/com/android/settingslib/spa/framework/theme/SettingsFontFamily.kt
+++ b/packages/SettingsLib/Spa/spa/src/com/android/settingslib/spa/framework/theme/SettingsFontFamily.kt
@@ -21,45 +21,51 @@
 import android.annotation.SuppressLint
 import android.content.Context
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.remember
-import androidx.compose.ui.platform.LocalContext
-import androidx.compose.ui.platform.LocalInspectionMode
 import androidx.compose.ui.text.ExperimentalTextApi
 import androidx.compose.ui.text.font.DeviceFontFamilyName
 import androidx.compose.ui.text.font.Font
 import androidx.compose.ui.text.font.FontFamily
 import androidx.compose.ui.text.font.FontWeight
+import com.android.settingslib.spa.framework.compose.rememberContext
 
 internal data class SettingsFontFamily(
-    val brand: FontFamily = FontFamily.Default,
-    val plain: FontFamily = FontFamily.Default,
+    val brand: FontFamily,
+    val plain: FontFamily,
 )
 
-private fun Context.getSettingsFontFamily(inInspection: Boolean): SettingsFontFamily {
-    if (inInspection) {
-        return SettingsFontFamily()
-    }
+private fun Context.getSettingsFontFamily(): SettingsFontFamily {
     return SettingsFontFamily(
-        brand = FontFamily(
-            Font(getFontFamilyName("config_headlineFontFamily"), FontWeight.Normal),
-            Font(getFontFamilyName("config_headlineFontFamilyMedium"), FontWeight.Medium),
+        brand = getFontFamily(
+            configFontFamilyNormal = "config_headlineFontFamily",
+            configFontFamilyMedium = "config_headlineFontFamilyMedium",
         ),
-        plain = FontFamily(
-            Font(getFontFamilyName("config_bodyFontFamily"), FontWeight.Normal),
-            Font(getFontFamilyName("config_bodyFontFamilyMedium"), FontWeight.Medium),
+        plain = getFontFamily(
+            configFontFamilyNormal = "config_bodyFontFamily",
+            configFontFamilyMedium = "config_bodyFontFamilyMedium",
         ),
     )
 }
 
-private fun Context.getFontFamilyName(configName: String): DeviceFontFamilyName {
+private fun Context.getFontFamily(
+    configFontFamilyNormal: String,
+    configFontFamilyMedium: String,
+): FontFamily {
+    val fontFamilyNormal = getAndroidConfig(configFontFamilyNormal)
+    val fontFamilyMedium = getAndroidConfig(configFontFamilyMedium)
+    if (fontFamilyNormal.isEmpty() || fontFamilyMedium.isEmpty()) return FontFamily.Default
+    return FontFamily(
+        Font(DeviceFontFamilyName(fontFamilyNormal), FontWeight.Normal),
+        Font(DeviceFontFamilyName(fontFamilyMedium), FontWeight.Medium),
+    )
+}
+
+private fun Context.getAndroidConfig(configName: String): String {
     @SuppressLint("DiscouragedApi")
     val configId = resources.getIdentifier(configName, "string", "android")
-    return DeviceFontFamilyName(resources.getString(configId))
+    return resources.getString(configId)
 }
 
 @Composable
 internal fun rememberSettingsFontFamily(): SettingsFontFamily {
-    val context = LocalContext.current
-    val inInspection = LocalInspectionMode.current
-    return remember { context.getSettingsFontFamily(inInspection) }
+    return rememberContext(Context::getSettingsFontFamily)
 }
diff --git a/packages/SettingsLib/Spa/tests/Android.bp b/packages/SettingsLib/Spa/tests/Android.bp
index 7491045..2449dec 100644
--- a/packages/SettingsLib/Spa/tests/Android.bp
+++ b/packages/SettingsLib/Spa/tests/Android.bp
@@ -31,6 +31,7 @@
         "androidx.compose.runtime_runtime",
         "androidx.compose.ui_ui-test-junit4",
         "androidx.compose.ui_ui-test-manifest",
+        "mockito-target-minus-junit4",
         "truth-prebuilt",
     ],
     kotlincflags: ["-Xjvm-default=all"],
diff --git a/packages/SettingsLib/Spa/tests/build.gradle b/packages/SettingsLib/Spa/tests/build.gradle
index 4b4c6a3..5261091 100644
--- a/packages/SettingsLib/Spa/tests/build.gradle
+++ b/packages/SettingsLib/Spa/tests/build.gradle
@@ -58,9 +58,10 @@
 }
 
 dependencies {
-    androidTestImplementation(project(":spa"))
-    androidTestImplementation 'androidx.test.ext:junit-ktx:1.1.3'
-    androidTestImplementation("androidx.compose.ui:ui-test-junit4:$jetpack_compose_version")
-    androidTestImplementation 'com.google.truth:truth:1.1.3'
+    androidTestImplementation project(":spa")
+    androidTestImplementation "androidx.test.ext:junit-ktx:1.1.3"
+    androidTestImplementation "androidx.compose.ui:ui-test-junit4:$jetpack_compose_version"
+    androidTestImplementation "com.google.truth:truth:1.1.3"
+    androidTestImplementation "org.mockito:mockito-android:3.4.6"
     androidTestDebugImplementation "androidx.compose.ui:ui-test-manifest:$jetpack_compose_version"
 }
diff --git a/packages/SettingsLib/Spa/tests/src/com/android/settingslib/spa/framework/theme/SettingsThemeTest.kt b/packages/SettingsLib/Spa/tests/src/com/android/settingslib/spa/framework/theme/SettingsThemeTest.kt
new file mode 100644
index 0000000..2ff3039
--- /dev/null
+++ b/packages/SettingsLib/Spa/tests/src/com/android/settingslib/spa/framework/theme/SettingsThemeTest.kt
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settingslib.spa.framework.theme
+
+import android.content.Context
+import android.content.res.Resources
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Typography
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.test.junit4.createComposeRule
+import androidx.compose.ui.text.font.FontFamily
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.google.common.truth.Truth.assertThat
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.Mock
+import org.mockito.Mockito.anyInt
+import org.mockito.junit.MockitoJUnit
+import org.mockito.junit.MockitoRule
+import org.mockito.Mockito.`when` as whenever
+
+@RunWith(AndroidJUnit4::class)
+class SettingsThemeTest {
+    @get:Rule
+    val mockito: MockitoRule = MockitoJUnit.rule()
+
+    @get:Rule
+    val composeTestRule = createComposeRule()
+
+    @Mock
+    private lateinit var context: Context
+
+    @Mock
+    private lateinit var resources: Resources
+
+    private var nextMockResId = 1
+
+    @Before
+    fun setUp() {
+        whenever(context.resources).thenReturn(resources)
+        whenever(resources.getString(anyInt())).thenReturn("")
+    }
+
+    private fun mockAndroidConfig(configName: String, configValue: String) {
+        whenever(resources.getIdentifier(configName, "string", "android"))
+            .thenReturn(nextMockResId)
+        whenever(resources.getString(nextMockResId)).thenReturn(configValue)
+        nextMockResId++
+    }
+
+    @Test
+    fun noFontFamilyConfig_useDefaultFontFamily() {
+        val fontFamily = getFontFamily()
+
+        assertThat(fontFamily.headlineLarge.fontFamily).isSameInstanceAs(FontFamily.Default)
+        assertThat(fontFamily.bodyLarge.fontFamily).isSameInstanceAs(FontFamily.Default)
+    }
+
+    @Test
+    fun hasFontFamilyConfig_useConfiguredFontFamily() {
+        mockAndroidConfig("config_headlineFontFamily", "HeadlineNormal")
+        mockAndroidConfig("config_headlineFontFamilyMedium", "HeadlineMedium")
+        mockAndroidConfig("config_bodyFontFamily", "BodyNormal")
+        mockAndroidConfig("config_bodyFontFamilyMedium", "BodyMedium")
+
+        val fontFamily = getFontFamily()
+
+        val headlineFontFamily = fontFamily.headlineLarge.fontFamily.toString()
+        assertThat(headlineFontFamily).contains("HeadlineNormal")
+        assertThat(headlineFontFamily).contains("HeadlineMedium")
+        val bodyFontFamily = fontFamily.bodyLarge.fontFamily.toString()
+        assertThat(bodyFontFamily).contains("BodyNormal")
+        assertThat(bodyFontFamily).contains("BodyMedium")
+    }
+
+    private fun getFontFamily(): Typography {
+        lateinit var typography: Typography
+        composeTestRule.setContent {
+            CompositionLocalProvider(LocalContext provides context) {
+                SettingsTheme {
+                    typography = MaterialTheme.typography
+                }
+            }
+        }
+        return typography
+    }
+}