add support for default trsnager accounts

app/src/main/java/sh/sar/basedbank/ui/home/AccountHistoryAdapter.kt

@@ -37,7 +37,12 @@ class AccountHistoryAdapter(
     var onImageNeeded: ((counterpartyName: String) -> Unit)? = null
     var onIconUrlNeeded: ((url: String) -> Unit)? = null
     var onTransferClick: ((BankAccount) -> Unit)? = null
+    var onDefaultToggle: ((Boolean) -> Unit)? = null
     private var hideAmounts: Boolean = false
+    var showDefaultToggle: Boolean = false
+        set(value) { if (field == value) return; field = value; notifyItemChanged(0) }
+    var isDefaultAccount: Boolean = false
+        set(value) { if (field == value) return; field = value; notifyItemChanged(0) }
 
     fun setHideAmounts(hide: Boolean) {
         if (hideAmounts == hide) return
@@ -174,6 +179,20 @@ class AccountHistoryAdapter(
                 b.llHeaderBlocked.visibility = View.GONE
             }
             b.btnHeaderTransfer.setOnClickListener { onTransferClick?.invoke(account) }
+
+            if (showDefaultToggle) {
+                b.dividerDefaultAccount.visibility = View.VISIBLE
+                b.llDefaultAccountRow.visibility = View.VISIBLE
+                b.switchDefaultAccount.setOnCheckedChangeListener(null)
+                b.switchDefaultAccount.isChecked = isDefaultAccount
+                b.switchDefaultAccount.setOnCheckedChangeListener { _, checked ->
+                    isDefaultAccount = checked
+                    onDefaultToggle?.invoke(checked)
+                }
+            } else {
+                b.dividerDefaultAccount.visibility = View.GONE
+                b.llDefaultAccountRow.visibility = View.GONE
+            }
         }
     }
 

app/src/main/java/sh/sar/basedbank/ui/home/AccountHistoryFragment.kt

@@ -29,7 +29,9 @@ import sh.sar.basedbank.api.models.BankTransaction
 import sh.sar.basedbank.api.mib.TransactionCache
 import sh.sar.basedbank.databinding.FragmentAccountHistoryBinding
 import sh.sar.basedbank.util.AccountHistoryParser
+import sh.sar.basedbank.util.AccountListParser
 import sh.sar.basedbank.util.ContactImageCache
+import sh.sar.basedbank.util.CredentialStore
 import sh.sar.basedbank.util.HistoryFetcher
 import sh.sar.basedbank.util.MerchantIconCache
 
@@ -80,6 +82,23 @@ class AccountHistoryFragment : Fragment() {
         }
         adapter.setHideAmounts(viewModel.hideAmounts.value ?: false)
         viewModel.hideAmounts.observe(viewLifecycleOwner) { adapter.setHideAmounts(it) }
+
+        // Show default account toggle only for non-card accounts
+        val isCard = AccountListParser.from(account)?.isCard ?: false
+        if (!isCard) {
+            val store = CredentialStore(requireContext())
+            adapter.showDefaultToggle = true
+            adapter.isDefaultAccount = store.getDefaultAccountNumber() == account.accountNumber
+            adapter.onDefaultToggle = { isChecked ->
+                if (isChecked) {
+                    store.setDefaultAccountNumber(account.accountNumber)
+                } else {
+                    if (store.getDefaultAccountNumber() == account.accountNumber) {
+                        store.setDefaultAccountNumber(null)
+                    }
+                }
+            }
+        }
         binding.recyclerView.layoutManager = LinearLayoutManager(requireContext())
         binding.recyclerView.adapter = adapter
 
@@ -131,7 +150,12 @@ class AccountHistoryFragment : Fragment() {
 
     override fun onResume() {
         super.onResume()
-        if (::account.isInitialized) requireActivity().title = account.accountBriefName
+        if (::account.isInitialized) {
+            requireActivity().title = account.accountBriefName
+            if (adapter.showDefaultToggle) {
+                adapter.isDefaultAccount = CredentialStore(requireContext()).getDefaultAccountNumber() == account.accountNumber
+            }
+        }
     }
 
     private fun filterAndDisplay() {

app/src/main/java/sh/sar/basedbank/ui/home/PayMvQrFragment.kt

@@ -124,6 +124,20 @@ class PayMvQrFragment : Fragment() {
                 selectedAccount = picked
                 scheduleGenerate()
             }
+
+            // Auto-select default account if none is selected yet
+            if (selectedAccount == null) {
+                val defaultNum = CredentialStore(requireContext()).getDefaultAccountNumber()
+                if (defaultNum != null) {
+                    val defaultAcc = eligible.firstOrNull { it.accountNumber == defaultNum }
+                    if (defaultAcc != null) {
+                        selectedAccount = defaultAcc
+                        val prefix = if (defaultAcc.bank == "BML" && defaultAcc.profileName.isNotBlank()) "${defaultAcc.profileName} · " else ""
+                        binding.actvAccount.setText("$prefix${defaultAcc.accountBriefName}", false)
+                        scheduleGenerate()
+                    }
+                }
+            }
         }
     }
 

app/src/main/java/sh/sar/basedbank/ui/home/TransferFragment.kt

@@ -573,8 +573,21 @@ class TransferFragment : Fragment() {
 
     private fun lookupAccount() {
         if (selectedAccount == null) {
-            Toast.makeText(requireContext(), R.string.transfer_select_source_first, Toast.LENGTH_SHORT).show()
-            return
+            val defaultNum = CredentialStore(requireContext()).getDefaultAccountNumber()
+            if (defaultNum != null) {
+                val allAccounts = viewModel.accounts.value ?: emptyList()
+                val defaultAcc = allAccounts.firstOrNull { it.accountNumber == defaultNum }
+                if (defaultAcc != null) {
+                    selectedAccount = defaultAcc
+                    updateAmountPrefix(defaultAcc)
+                    showFromCard(defaultAcc)
+                    updateTransferButton()
+                }
+            }
+            if (selectedAccount == null) {
+                Toast.makeText(requireContext(), R.string.transfer_no_from_account, Toast.LENGTH_SHORT).show()
+                return
+            }
         }
         val accountNumber = AccountInputParser.normalize(binding.etTo.text?.toString()?.trim() ?: "")
         if (accountNumber.isBlank()) {

app/src/main/java/sh/sar/basedbank/util/CredentialStore.kt

@@ -627,6 +627,18 @@ class CredentialStore(context: Context) {
         editor.apply()
     }
 
+    // ── Default transfer/QR account ───────────────────────────────────────────
+
+    /** Account number the user has pinned as their default source for transfers and PayMV QR, or null. */
+    fun getDefaultAccountNumber(): String? = prefs.getString("default_account_number", null)
+
+    fun setDefaultAccountNumber(accountNumber: String?) {
+        val editor = prefs.edit()
+        if (accountNumber == null) editor.remove("default_account_number")
+        else editor.putString("default_account_number", accountNumber)
+        editor.apply()
+    }
+
     // ── Dashboard card visibility ─────────────────────────────────────────────
 
     fun getHiddenDashboardCardNumbers(): Set<String> =

app/src/main/res/layout/item_account_history_header.xml

@@ -182,6 +182,55 @@
 
         </LinearLayout>
 
+        <!-- Default account divider + row (shown only for non-card accounts) -->
+        <View
+            android:id="@+id/dividerDefaultAccount"
+            android:layout_width="match_parent"
+            android:layout_height="1dp"
+            android:layout_marginTop="16dp"
+            android:background="?attr/colorOutlineVariant"
+            android:visibility="gone" />
+
+        <LinearLayout
+            android:id="@+id/llDefaultAccountRow"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:orientation="horizontal"
+            android:gravity="center_vertical"
+            android:layout_marginTop="12dp"
+            android:visibility="gone">
+
+            <LinearLayout
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:orientation="vertical">
+
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="Default account"
+                    android:textAppearance="?attr/textAppearanceBodyMedium"
+                    android:textColor="?attr/colorOnSurface" />
+
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="Auto-selected for transfers and PayMV QR"
+                    android:textAppearance="?attr/textAppearanceLabelSmall"
+                    android:textColor="?attr/colorOnSurfaceVariant"
+                    android:layout_marginTop="2dp" />
+
+            </LinearLayout>
+
+            <com.google.android.material.materialswitch.MaterialSwitch
+                android:id="@+id/switchDefaultAccount"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_marginStart="12dp" />
+
+        </LinearLayout>
+
     </LinearLayout>
 
 </com.google.android.material.card.MaterialCardView>

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

@@ -246,6 +246,7 @@
     <string name="camera_permission_profile_message">Camera access is needed to take a photo. Please grant the permission in Settings.</string>
     <string name="go_to_settings">Go to Settings</string>
     <string name="transfer_select_source_first">Select a source account first</string>
+    <string name="transfer_no_from_account">Please set a default account or select From account first</string>
     <string name="transfer_enter_account_first">Enter an account number first</string>
     <string name="transfer_account_not_found">Account not found</string>
     <string name="transfer_session_unavailable">Session unavailable — please re-login</string>