feat(settings): in-app chat font size setting (#1004) (#1005)

Co-authored-by: M57 <hy4ri@users.noreply.github.com>

app/src/main/java/com/m57/hermescontrol/MainActivity.kt

@@ -54,10 +54,12 @@ class MainActivity : ComponentActivity() {
             val themePreference by AuthManager.themePreferenceFlow.collectAsState()
             val useDynamicColors by AuthManager.useDynamicColorsFlow.collectAsState()
             val themePreset by AuthManager.themePresetFlow.collectAsState()
+            val chatFontScale by AuthManager.chatFontScaleFlow.collectAsState()
             HermesControlTheme(
                 themePreference = themePreference,
                 useDynamicColors = useDynamicColors,
                 themePreset = themePreset,
+                chatFontScale = chatFontScale,
             ) {
                 Surface(
                     modifier = Modifier.fillMaxSize(),

app/src/main/java/com/m57/hermescontrol/data/config/ServerStoreState.kt

@@ -21,6 +21,7 @@ data class ServerStoreState(
     val wsAuthParam: String = "token",
     val typingEffectEnabled: Boolean = true,
     val typingEffectDelayMs: Int = 30,
+    val chatFontScale: Float = 1.0f,
     // App display language. "system" = follow device locale; otherwise a BCP-47
     // language code such as "en" or "ko". Applied via ContextWrapper in MainActivity.
     val appLanguage: String = "system",

app/src/main/java/com/m57/hermescontrol/data/local/AuthManager.kt

@@ -74,6 +74,9 @@ object AuthManager {
     private val _themePresetFlow = MutableStateFlow<ThemePreset>(ThemePreset.DEFAULT)
     val themePresetFlow: StateFlow<ThemePreset> = _themePresetFlow.asStateFlow()
 
+    private val _chatFontScaleFlow = MutableStateFlow<Float>(1.0f)
+    val chatFontScaleFlow: StateFlow<Float> = _chatFontScaleFlow.asStateFlow()
+
     private val _tokenFlow = MutableStateFlow<String?>(null)
     val tokenFlow: StateFlow<String?> = _tokenFlow.asStateFlow()
 
@@ -180,6 +183,7 @@ object AuthManager {
                     _themePreferenceFlow.value = state.themePreference
                     _useDynamicColorsFlow.value = state.useDynamicColors
                     _themePresetFlow.value = state.themePreset
+                    _chatFontScaleFlow.value = state.chatFontScale
                     // B7 (Jul 08 2026, kanban t_470): keep cookie scope aligned with active profile.
                     appScope?.launch { syncCookieStoreForProfile(state.selectedProfileId) }
                 }
@@ -640,6 +644,15 @@ object AuthManager {
         serverStore.update { it.copy(typingEffectDelayMs = delayMs) }
     }
 
+    // ── Chat Font Scale (issue #1004) ───────────────────────────────────
+
+    fun getChatFontScale(): Float = serverStore.getLatestState().chatFontScale
+
+    fun setChatFontScale(scale: Float) {
+        serverStore.update { it.copy(chatFontScale = scale) }
+        _chatFontScaleFlow.value = scale
+    }
+
     // ── In-app update check (issue #867) ─────────────────────────────────
 
     /** App version the silent update check last completed for (null = never). */

app/src/main/java/com/m57/hermescontrol/theme/Theme.kt

@@ -26,6 +26,7 @@ enum class ThemePreset { DEFAULT, MONOCHROME, GRUVBOX, CATPPUCCIN, AMOLED, NORD
 
 val LocalThemePreference = compositionLocalOf { ThemePreference.SYSTEM }
 val LocalThemePreset = compositionLocalOf { ThemePreset.DEFAULT }
+val LocalChatFontScale = compositionLocalOf { 1.0f }
 
 /**
  * The 6 preset themes — one file each, all built from the same
@@ -75,6 +76,7 @@ fun HermesControlTheme(
     themePreference: ThemePreference = LocalThemePreference.current,
     useDynamicColors: Boolean = true,
     themePreset: ThemePreset = ThemePreset.DEFAULT,
+    chatFontScale: Float = LocalChatFontScale.current,
     content: @Composable () -> Unit,
 ) {
     val darkTheme =
@@ -103,6 +105,7 @@ fun HermesControlTheme(
     CompositionLocalProvider(
         LocalThemePreference provides themePreference,
         LocalThemePreset provides themePreset,
+        LocalChatFontScale provides chatFontScale,
         LocalHermesStatusColors provides statusColors,
         LocalSpacing provides SpacingDefaults,
         LocalMotion provides MotionDefaults,

app/src/main/java/com/m57/hermescontrol/ui/bots/group/GroupChatScreen.kt

@@ -32,6 +32,7 @@ import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Surface
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
@@ -43,14 +44,17 @@ import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.focus.onFocusChanged
 import androidx.compose.ui.graphics.SolidColor
+import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.input.ImeAction
 import androidx.compose.ui.text.input.TextFieldValue
+import androidx.compose.ui.unit.Density
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.m57.hermescontrol.R
+import com.m57.hermescontrol.theme.LocalChatFontScale
 import com.m57.hermescontrol.ui.chat.MarkdownText
 import com.m57.hermescontrol.ui.common.BotAvatar
 import com.m57.hermescontrol.ui.common.EmptyState
@@ -141,6 +145,17 @@ fun GroupChatScreen(
                 }
 
                 else -> {
+                    val currentDensity = LocalDensity.current
+                    val chatFontScale = LocalChatFontScale.current
+                    val chatDensity =
+                        remember(currentDensity, chatFontScale) {
+                            Density(
+                                density = currentDensity.density,
+                                fontScale = currentDensity.fontScale * chatFontScale,
+                            )
+                        }
+
+                    CompositionLocalProvider(LocalDensity provides chatDensity) {
                         LazyColumn(
                             state = listState,
                             modifier =
@@ -179,6 +194,7 @@ fun GroupChatScreen(
                         }
                     }
                 }
+            }
 
             // ── COMPOSER (uses TextFieldValue + embedded Send button matching ChatComposer) ──
             Surface(

app/src/main/java/com/m57/hermescontrol/ui/chat/fullbleed/FullBleedChatList.kt

@@ -10,13 +10,17 @@ import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.material3.CircularProgressIndicator
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.remember
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.unit.Density
 import androidx.compose.ui.unit.dp
 import com.m57.hermescontrol.R
+import com.m57.hermescontrol.theme.LocalChatFontScale
 import com.m57.hermescontrol.ui.chat.ChatBubble
 import com.m57.hermescontrol.ui.chat.ChatMessage
 import com.m57.hermescontrol.ui.chat.ChatSearchState
@@ -116,6 +120,17 @@ fun FullBleedChatList(
             }
         }
 
+        val currentDensity = LocalDensity.current
+        val chatFontScale = LocalChatFontScale.current
+        val chatDensity =
+            remember(currentDensity, chatFontScale) {
+                Density(
+                    density = currentDensity.density,
+                    fontScale = currentDensity.fontScale * chatFontScale,
+                )
+            }
+
+        CompositionLocalProvider(LocalDensity provides chatDensity) {
             LazyColumn(
                 state = listState,
                 modifier = Modifier.fillMaxSize(),
@@ -293,6 +308,7 @@ fun FullBleedChatList(
                 }
             }
         }
+    }
 }
 
 @Composable

app/src/main/java/com/m57/hermescontrol/ui/settings/SettingsSubPages.kt

@@ -191,6 +191,8 @@ internal fun SettingsChatPage(
                 onTypingEffectEnabledChange = viewModel::onTypingEffectEnabledChange,
                 typingEffectDelayMs = state.typingEffectDelayMs,
                 onTypingEffectDelayMsChange = viewModel::onTypingEffectDelayMsChange,
+                chatFontScale = state.chatFontScale,
+                onChatFontScaleChange = viewModel::onChatFontScaleChange,
             )
         }
     }

app/src/main/java/com/m57/hermescontrol/ui/settings/SettingsViewModel.kt

@@ -36,6 +36,7 @@ data class SettingsUiState(
     val isSaved: Boolean = false,
     val typingEffectEnabled: Boolean = false,
     val typingEffectDelayMs: Int = 30,
+    val chatFontScale: Float = 1.0f,
     val profiles: List<ConnectionProfile> = emptyList(),
     val selectedProfileId: String? = null,
     val renameProfileName: String = "",
@@ -76,6 +77,7 @@ class SettingsViewModel(
         val themePreset = AuthManager.getThemePreset()
         val typingEffectEnabled = AuthManager.isTypingEffectEnabled()
         val typingEffectDelayMs = AuthManager.getTypingEffectDelayMs()
+        val chatFontScale = AuthManager.getChatFontScale()
         val profiles = AuthManager.getConnectionProfiles()
         val appLanguage = AuthManager.getAppLanguage()
         val renameProfileName =
@@ -95,6 +97,7 @@ class SettingsViewModel(
                 themePreset = themePreset,
                 typingEffectEnabled = typingEffectEnabled,
                 typingEffectDelayMs = typingEffectDelayMs,
+                chatFontScale = chatFontScale,
                 profiles = profiles,
                 selectedProfileId = selectedId,
                 renameProfileName = renameProfileName,
@@ -310,6 +313,11 @@ class SettingsViewModel(
         AuthManager.setTypingEffectDelayMs(delayMs)
     }
 
+    fun onChatFontScaleChange(scale: Float) {
+        _uiState.update { it.copy(chatFontScale = scale, isSaved = false) }
+        AuthManager.setChatFontScale(scale)
+    }
+
     /** Clear all auth credentials — logs out and returns to landing screen. */
     fun logout() {
         AuthManager.setToken(null)

app/src/main/java/com/m57/hermescontrol/ui/settings/components/AppearanceSection.kt

@@ -10,6 +10,7 @@ import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material3.DropdownMenu
 import androidx.compose.material3.DropdownMenuItem
 import androidx.compose.material3.MaterialTheme
@@ -18,22 +19,29 @@ import androidx.compose.material3.SegmentedButton
 import androidx.compose.material3.SegmentedButtonDefaults
 import androidx.compose.material3.SingleChoiceSegmentedButtonRow
 import androidx.compose.material3.Slider
+import androidx.compose.material3.Surface
 import androidx.compose.material3.Switch
 import androidx.compose.material3.SwitchDefaults
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.Density
 import androidx.compose.ui.unit.dp
 import com.m57.hermescontrol.R
 import com.m57.hermescontrol.theme.ThemePreference
 import com.m57.hermescontrol.theme.ThemePreset
 import com.m57.hermescontrol.ui.settings.SectionCard
+import kotlin.math.abs
+import kotlin.math.roundToInt
 
 @Composable
 internal fun AppearanceSection(
@@ -194,10 +202,172 @@ internal fun ChatSection(
     onTypingEffectEnabledChange: (Boolean) -> Unit,
     typingEffectDelayMs: Int,
     onTypingEffectDelayMsChange: (Int) -> Unit,
+    chatFontScale: Float = 1.0f,
+    onChatFontScaleChange: (Float) -> Unit = {},
 ) {
+    val fontScaleOptions = listOf(0.85f, 1.0f, 1.15f, 1.30f, 1.50f)
+    val currentIndex =
+        fontScaleOptions.indexOfFirst { abs(it - chatFontScale) < 0.05f }
+            .takeIf { it >= 0 } ?: 1
+
     SectionCard {
+        Row(
+            modifier = Modifier.fillMaxWidth(),
+            horizontalArrangement = Arrangement.SpaceBetween,
+            verticalAlignment = Alignment.CenterVertically,
+        ) {
+            Column(modifier = Modifier.weight(1f)) {
+                Text(
+                    text = stringResource(R.string.settings_item_chat_font_size),
+                    style = MaterialTheme.typography.bodyLarge,
+                )
+                Text(
+                    text = stringResource(R.string.settings_desc_chat_font_size),
+                    style =
+                        MaterialTheme.typography.bodySmall.copy(
+                            color = MaterialTheme.colorScheme.onSurfaceVariant,
+                        ),
+                )
+            }
+            val scaleLabel =
+                when (currentIndex) {
+                    0 -> stringResource(R.string.settings_font_scale_small)
+                    1 -> stringResource(R.string.settings_font_scale_default)
+                    2 -> stringResource(R.string.settings_font_scale_large)
+                    3 -> stringResource(R.string.settings_font_scale_xlarge)
+                    else -> stringResource(R.string.settings_font_scale_huge)
+                }
+            Text(
+                text = scaleLabel,
+                style =
+                    MaterialTheme.typography.labelMedium.copy(
+                        color = MaterialTheme.colorScheme.primary,
+                        fontWeight = FontWeight.SemiBold,
+                    ),
+            )
+        }
+
+        Spacer(modifier = Modifier.height(8.dp))
+
+        Slider(
+            value = currentIndex.toFloat(),
+            onValueChange = { onChatFontScaleChange(fontScaleOptions[it.roundToInt()]) },
+            valueRange = 0f..(fontScaleOptions.size - 1).toFloat(),
+            steps = fontScaleOptions.size - 2,
+            modifier = Modifier.fillMaxWidth(),
+        )
+
+        Row(
+            modifier = Modifier.fillMaxWidth(),
+            horizontalArrangement = Arrangement.SpaceBetween,
+        ) {
+            Text(
+                text = "0.85×",
+                style =
+                    MaterialTheme.typography.labelSmall.copy(
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                    ),
+            )
+            Text(
+                text = "1.0×",
+                style =
+                    MaterialTheme.typography.labelSmall.copy(
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                    ),
+            )
+            Text(
+                text = "1.5×",
+                style =
+                    MaterialTheme.typography.labelSmall.copy(
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                    ),
+            )
+        }
+
         Spacer(modifier = Modifier.height(16.dp))
 
+        Text(
+            text = stringResource(R.string.settings_chat_preview_title),
+            style =
+                MaterialTheme.typography.labelMedium.copy(
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                ),
+        )
+
+        Spacer(modifier = Modifier.height(8.dp))
+
+        val currentDensity = LocalDensity.current
+        val previewDensity =
+            remember(currentDensity, chatFontScale) {
+                Density(
+                    density = currentDensity.density,
+                    fontScale = currentDensity.fontScale * chatFontScale,
+                )
+            }
+
+        CompositionLocalProvider(LocalDensity provides previewDensity) {
+            Surface(
+                modifier = Modifier.fillMaxWidth(),
+                shape = RoundedCornerShape(12.dp),
+                color = MaterialTheme.colorScheme.surfaceContainer,
+            ) {
+                Column(
+                    modifier = Modifier.padding(12.dp),
+                    verticalArrangement = Arrangement.spacedBy(8.dp),
+                ) {
+                    // User bubble preview
+                    Row(
+                        modifier = Modifier.fillMaxWidth(),
+                        horizontalArrangement = Arrangement.End,
+                    ) {
+                        Surface(
+                            shape =
+                                RoundedCornerShape(
+                                    topStart = 14.dp,
+                                    topEnd = 14.dp,
+                                    bottomStart = 14.dp,
+                                    bottomEnd = 4.dp,
+                                ),
+                            color = MaterialTheme.colorScheme.primary,
+                        ) {
+                            Text(
+                                text = stringResource(R.string.settings_chat_preview_user),
+                                style = MaterialTheme.typography.bodyMedium,
+                                color = MaterialTheme.colorScheme.onPrimary,
+                                modifier = Modifier.padding(horizontal = 10.dp, vertical = 6.dp),
+                            )
+                        }
+                    }
+
+                    // Assistant bubble preview
+                    Row(
+                        modifier = Modifier.fillMaxWidth(),
+                        horizontalArrangement = Arrangement.Start,
+                    ) {
+                        Surface(
+                            shape =
+                                RoundedCornerShape(
+                                    topStart = 14.dp,
+                                    topEnd = 14.dp,
+                                    bottomStart = 4.dp,
+                                    bottomEnd = 14.dp,
+                                ),
+                            color = MaterialTheme.colorScheme.surfaceContainerHigh,
+                        ) {
+                            Text(
+                                text = stringResource(R.string.settings_chat_preview_agent),
+                                style = MaterialTheme.typography.bodyMedium,
+                                color = MaterialTheme.colorScheme.onSurface,
+                                modifier = Modifier.padding(horizontal = 10.dp, vertical = 6.dp),
+                            )
+                        }
+                    }
+                }
+            }
+        }
+
+        Spacer(modifier = Modifier.height(20.dp))
+
         Row(
             modifier = Modifier.fillMaxWidth(),
             horizontalArrangement = Arrangement.SpaceBetween,

app/src/main/res/values-ko/strings.xml

@@ -187,6 +187,17 @@
     <string name="settings_item_typing_delay">지연: %1$d ms</string>
     <string name="settings_delay_10ms">10 ms</string>
     <string name="settings_delay_100ms">100 ms</string>
+    <string name="settings_item_chat_font_size">채팅 글꼴 크기</string>
+    <string name="settings_desc_chat_font_size">채팅 메시지의 텍스트 크기를 조절합니다</string>
+    <string name="settings_font_scale_value">글꼴 크기: %1$s</string>
+    <string name="settings_font_scale_small">작게 (0.85×)</string>
+    <string name="settings_font_scale_default">기본 (1.0×)</string>
+    <string name="settings_font_scale_large">크게 (1.15×)</string>
+    <string name="settings_font_scale_xlarge">아주 크게 (1.3×)</string>
+    <string name="settings_font_scale_huge">최대 (1.5×)</string>
+    <string name="settings_chat_preview_title">미리보기</string>
+    <string name="settings_chat_preview_user">채팅 텍스트 크기를 조절할 수 있나요?</string>
+    <string name="settings_chat_preview_agent">완료되었습니다! 여기에서 글꼴 크기를 조정할 수 있습니다.</string>
     <string name="settings_action_test_connection">연결 테스트</string>
     <string name="settings_sec_about">정보</string>
     <string name="settings_about_app_name">헤르메스 모바일</string>

app/src/main/res/values-zh/strings.xml

@@ -184,6 +184,17 @@
     <string name="settings_item_typing_delay">延迟：%1$d 毫秒</string>
     <string name="settings_delay_10ms">10 毫秒</string>
     <string name="settings_delay_100ms">100 毫秒</string>
+    <string name="settings_item_chat_font_size">聊天字体大小</string>
+    <string name="settings_desc_chat_font_size">缩放聊天消息文字大小</string>
+    <string name="settings_font_scale_value">字体大小：%1$s</string>
+    <string name="settings_font_scale_small">小 (0.85×)</string>
+    <string name="settings_font_scale_default">默认 (1.0×)</string>
+    <string name="settings_font_scale_large">大 (1.15×)</string>
+    <string name="settings_font_scale_xlarge">特大 (1.3×)</string>
+    <string name="settings_font_scale_huge">极大 (1.5×)</string>
+    <string name="settings_chat_preview_title">预览</string>
+    <string name="settings_chat_preview_user">可以调整聊天字体大小吗？</string>
+    <string name="settings_chat_preview_agent">已搞定！你可以在这里自定义字体缩放比例。</string>
     <string name="settings_action_test_connection">测试连接</string>
     <string name="settings_sec_about">关于</string>
     <string name="settings_sec_language">语言</string>

app/src/main/res/values/strings.xml

@@ -207,6 +207,17 @@
     <string name="settings_item_typing_delay">Delay: %1$d ms</string>
     <string name="settings_delay_10ms">10 ms</string>
     <string name="settings_delay_100ms">100 ms</string>
+    <string name="settings_item_chat_font_size">Chat Font Size</string>
+    <string name="settings_desc_chat_font_size">Scale text size in chat messages</string>
+    <string name="settings_font_scale_value">Font Size: %1$s</string>
+    <string name="settings_font_scale_small">Small (0.85×)</string>
+    <string name="settings_font_scale_default">Default (1.0×)</string>
+    <string name="settings_font_scale_large">Large (1.15×)</string>
+    <string name="settings_font_scale_xlarge">Extra Large (1.3×)</string>
+    <string name="settings_font_scale_huge">Huge (1.5×)</string>
+    <string name="settings_chat_preview_title">Preview</string>
+    <string name="settings_chat_preview_user">Can you adjust the chat text size?</string>
+    <string name="settings_chat_preview_agent">Done! You can customize the font scale right here.</string>
     <string name="settings_action_test_connection">Test Connection</string>
     <string name="settings_sec_about">About</string>
     <string name="settings_sec_language">Language</string>

app/src/test/java/com/m57/hermescontrol/data/config/ServerStoreTest.kt

@@ -15,6 +15,7 @@ class ServerStoreTest {
         assertEquals(9119, state.port)
         assertTrue(state.autoReconnect)
         assertEquals("token", state.wsAuthParam)
+        assertEquals(1.0f, state.chatFontScale)
         assertTrue(state.connectionProfiles.isEmpty())
         assertNull(state.selectedProfileId)
     }

app/src/test/java/com/m57/hermescontrol/ui/settings/SettingsViewModelTest.kt

@@ -68,6 +68,7 @@ class SettingsViewModelTest {
         every { AuthManager.getThemePreset() } returns ThemePreset.DEFAULT
         every { AuthManager.isTypingEffectEnabled() } returns true
         every { AuthManager.getTypingEffectDelayMs() } returns 30
+        every { AuthManager.getChatFontScale() } returns 1.0f
         every { AuthManager.getConnectionProfiles() } returns emptyList()
         every { AuthManager.getSelectedProfileId() } answers { storedSelectedProfileId }
         every { AuthManager.baseUrl() } returns "http://127.0.0.1:9119/"
@@ -79,6 +80,7 @@ class SettingsViewModelTest {
         every { AuthManager.setThemePreset(any()) } returns Unit
         every { AuthManager.setTypingEffectEnabled(any()) } returns Unit
         every { AuthManager.setTypingEffectDelayMs(any()) } returns Unit
+        every { AuthManager.setChatFontScale(any()) } returns Unit
         every { AuthManager.setSelectedProfileId(any()) } answers {
             storedSelectedProfileId = firstArg()
         }
@@ -130,6 +132,7 @@ class SettingsViewModelTest {
             every { AuthManager.getThemePreset() } returns ThemePreset.CATPPUCCIN
             every { AuthManager.isTypingEffectEnabled() } returns false
             every { AuthManager.getTypingEffectDelayMs() } returns 15
+            every { AuthManager.getChatFontScale() } returns 1.30f
             every { AuthManager.getConnectionProfiles() } returns testProfiles
             every { AuthManager.getAppLanguage() } returns "fr"
 
@@ -146,12 +149,23 @@ class SettingsViewModelTest {
             assertEquals(ThemePreset.CATPPUCCIN, state.themePreset)
             assertEquals(false, state.typingEffectEnabled)
             assertEquals(15, state.typingEffectDelayMs)
+            assertEquals(1.30f, state.chatFontScale)
             assertEquals(testProfiles, state.profiles)
             assertEquals("prof-2", state.selectedProfileId)
             assertEquals("Home", state.renameProfileName)
             assertEquals("fr", state.appLanguage)
         }
 
+    @Test
+    fun testOnChatFontScaleChange_updatesStateAndAuthManager() {
+        val viewModel = createViewModel()
+
+        viewModel.onChatFontScaleChange(1.15f)
+
+        assertEquals(1.15f, viewModel.uiState.value.chatFontScale)
+        verify { AuthManager.setChatFontScale(1.15f) }
+    }
+
     @Test
     fun testLoadSettings_noSelectedProfile_renameEmpty() {
         every { AuthManager.getConnectionProfiles() } returns testProfiles