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/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,