Merge main into feat-162-advanced-settings-hierarchy

app/src/main/kotlin/org/libremail/data/settings/SettingsRepository.kt

@@ -57,6 +57,14 @@ data class AppSettings(
      */
     val retentionCount: Int = 0,
     val retentionMonths: Int = 0,
+    /**
+     * The user-chosen default account (issue #163): the account [org.libremail.ui.compose.ComposeViewModel]
+     * uses when compose opens without an explicit account context (e.g. the unified-inbox FAB, or a
+     * `mailto:`/share intent with no account hint). Null means no default is set. A value here is not
+     * guaranteed to still name an existing account (see [SettingsRepository.clearDefaultAccountId]) —
+     * treat it as a hint to validate against the current account list, never as a trusted id.
+     */
+    val defaultAccountId: String? = null,
 )
 
 private object Keys {
@@ -71,6 +79,7 @@ private object Keys {
     val FETCH_POLICY = stringPreferencesKey("fetch_policy")
     val RETENTION_COUNT = intPreferencesKey("retention_count")
     val RETENTION_MONTHS = intPreferencesKey("retention_months")
+    val DEFAULT_ACCOUNT_ID = stringPreferencesKey("default_account_id")
     val BATTERY_PROMPT_HANDLED = booleanPreferencesKey("battery_prompt_handled")
     val CONTACTS_PROMPT_HANDLED = booleanPreferencesKey("contacts_prompt_handled")
     val CONTACTS_PERMISSION_REQUESTED = booleanPreferencesKey("contacts_permission_requested")
@@ -96,6 +105,7 @@ internal fun Preferences.toAppSettings(): AppSettings = AppSettings(
         ?: FetchPolicy.WIFI_ONLY,
     retentionCount = this[Keys.RETENTION_COUNT] ?: 0,
     retentionMonths = this[Keys.RETENTION_MONTHS] ?: 0,
+    defaultAccountId = this[Keys.DEFAULT_ACCOUNT_ID],
 )
 
 @Singleton
@@ -175,6 +185,29 @@ class SettingsRepository @Inject constructor(@ApplicationContext private val con
         context.settingsDataStore.edit { it[Keys.RETENTION_MONTHS] = value.coerceAtLeast(0) }
     }
 
+    /**
+     * Sets (or, when [value] is null, clears) the user-chosen default account (#163). Used directly by
+     * the per-account "set as default" toggle; deleting an account should go through
+     * [clearDefaultAccountId] instead so it can't clobber a different account's default.
+     */
+    suspend fun setDefaultAccountId(value: String?) {
+        context.settingsDataStore.edit {
+            if (value != null) it[Keys.DEFAULT_ACCOUNT_ID] = value else it.remove(Keys.DEFAULT_ACCOUNT_ID)
+        }
+    }
+
+    /**
+     * Clears the default-account preference, but only if it currently points at [accountId]. Called
+     * when that account is deleted, so a stale id is never left behind — and so deleting some other
+     * (non-default) account never disturbs an unrelated default. No-op if [accountId] isn't the current
+     * default.
+     */
+    suspend fun clearDefaultAccountId(accountId: String) {
+        context.settingsDataStore.edit {
+            if (it[Keys.DEFAULT_ACCOUNT_ID] == accountId) it.remove(Keys.DEFAULT_ACCOUNT_ID)
+        }
+    }
+
     private suspend fun put(key: Preferences.Key<Boolean>, value: Boolean) {
         context.settingsDataStore.edit { it[key] = value }
     }

app/src/main/kotlin/org/libremail/ui/compose/ComposeViewModel.kt

@@ -20,6 +20,7 @@ import org.libremail.contacts.ContactSuggestion
 import org.libremail.contacts.ContactsRepository
 import org.libremail.data.SignatureBlock
 import org.libremail.data.settings.AccountSettingsRepository
+import org.libremail.data.settings.SettingsRepository
 import org.libremail.data.settings.SignatureRepository
 import org.libremail.domain.model.Account
 import org.libremail.domain.model.Draft
@@ -62,6 +63,7 @@ class ComposeViewModel @Inject constructor(
     private val contactsRepository: ContactsRepository,
     private val accountSettingsRepository: AccountSettingsRepository,
     private val signatureRepository: SignatureRepository,
+    private val settingsRepository: SettingsRepository,
 ) : ViewModel() {
 
     private val draftId: String? =
@@ -120,7 +122,15 @@ class ComposeViewModel @Inject constructor(
             // signature. Reply/forward drafts already carry theirs, so they take the draft branch above.
             viewModelScope.launch {
                 val available = accountRepository.observeAccounts().first { it.isNotEmpty() }
-                val effectiveId = _state.value.fromAccountId ?: available.first().id
+                // The persisted default (#163) only counts if it still names an account that exists.
+                // Deleting the default account normally clears this via
+                // SettingsRepository.clearDefaultAccountId, but a stale id could still reach here (e.g.
+                // a Backup restore onto a device that never had the account) — validate rather than
+                // trust it, so it just falls through to the incidental "first account alphabetically"
+                // behavior instead of crashing or composing from a nonexistent account.
+                val defaultAccountId = settingsRepository.settings.first().defaultAccountId
+                val validDefaultAccountId = defaultAccountId?.takeIf { id -> available.any { it.id == id } }
+                val effectiveId = _state.value.fromAccountId ?: validDefaultAccountId ?: available.first().id
                 applySignature(effectiveId)
             }
         }

app/src/main/kotlin/org/libremail/ui/settings/AccountSettingsScreen.kt

@@ -39,6 +39,7 @@ fun AccountSettingsScreen(
     val settings by viewModel.settings.collectAsStateWithLifecycle()
     val signatureCount by viewModel.signatureCount.collectAsStateWithLifecycle()
     val defaultSignatureName by viewModel.defaultSignatureName.collectAsStateWithLifecycle()
+    val isDefaultAccount by viewModel.isDefaultAccount.collectAsStateWithLifecycle()
     val context = LocalContext.current
     val fallbackTitle = stringResource(R.string.settings_account_title)
 
@@ -63,6 +64,14 @@ fun AccountSettingsScreen(
                 .padding(padding)
                 .verticalScroll(rememberScrollState()),
         ) {
+            SwitchRow(
+                title = stringResource(R.string.settings_account_set_default),
+                checked = isDefaultAccount,
+                onCheckedChange = viewModel::setDefaultAccount,
+                subtitle = stringResource(R.string.settings_account_set_default_summary),
+            )
+            HorizontalDivider()
+
             SectionHeader(stringResource(R.string.settings_signature))
             SwitchRow(
                 title = stringResource(R.string.settings_signature_enable),

app/src/main/kotlin/org/libremail/ui/settings/AccountSettingsViewModel.kt

@@ -11,6 +11,7 @@ import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.stateIn
 import kotlinx.coroutines.launch
 import org.libremail.data.settings.AccountSettingsRepository
+import org.libremail.data.settings.SettingsRepository
 import org.libremail.data.settings.SignatureRepository
 import org.libremail.data.sync.SyncScheduler
 import org.libremail.domain.model.Account
@@ -27,6 +28,7 @@ class AccountSettingsViewModel @Inject constructor(
     private val accountSettingsRepository: AccountSettingsRepository,
     signatureRepository: SignatureRepository,
     private val syncScheduler: SyncScheduler,
+    private val settingsRepository: SettingsRepository,
 ) : ViewModel() {
 
     private val accountId: String =
@@ -39,6 +41,11 @@ class AccountSettingsViewModel @Inject constructor(
     val settings: StateFlow<AccountSettings> = accountSettingsRepository.observe(accountId)
         .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5_000), AccountSettings(accountId))
 
+    /** Whether this account is the user-chosen default (issue #163) — see [SettingsRepository]. */
+    val isDefaultAccount: StateFlow<Boolean> = settingsRepository.settings
+        .map { it.defaultAccountId == accountId }
+        .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5_000), false)
+
     private val signaturesFlow = signatureRepository.observeForAccount(accountId)
 
     val signatureCount: StateFlow<Int> = signaturesFlow
@@ -78,9 +85,27 @@ class AccountSettingsViewModel @Inject constructor(
         }
     }
 
+    /**
+     * Makes this account the default (used by compose's from-account fallback, #163), or clears the
+     * default when turned off. Only one account is default at a time — persisting this account's id
+     * implicitly un-defaults whichever one held it before.
+     */
+    fun setDefaultAccount(isDefault: Boolean) {
+        viewModelScope.launch {
+            if (isDefault) {
+                settingsRepository.setDefaultAccountId(accountId)
+            } else {
+                settingsRepository.clearDefaultAccountId(accountId)
+            }
+        }
+    }
+
     fun removeAccount(onRemoved: () -> Unit) {
         viewModelScope.launch {
             accountRepository.deleteAccount(accountId)
+            // Don't strand the preference on a deleted account; only clears it if this account was
+            // actually the default (see SettingsRepository.clearDefaultAccountId).
+            settingsRepository.clearDefaultAccountId(accountId)
             onRemoved()
         }
     }

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

@@ -253,6 +253,8 @@
 
     <!-- Per-account settings -->
     <string name="settings_account_title">Account</string>
+    <string name="settings_account_set_default">Default account</string>
+    <string name="settings_account_set_default_summary">Use this account for new messages when none is specified</string>
     <string name="settings_signature">Signature</string>
     <string name="settings_signature_enable">Append signature automatically</string>
     <string name="settings_signature_hint">Your signature</string>