Move some utility functions from gui code to engine

And reduce some of the clutter in these functions and their callers.

src/business/business-gnome/dialog-payment.c

@@ -821,15 +821,6 @@ gnc_payment_leave_amount_cb (GtkWidget *widget, GdkEventFocus *event,
     gnc_payment_window_check_payment (pw);
 }
 
-static gboolean AccountTypeOkForPayments (GNCAccountType type)
-{
-    if (xaccAccountIsAssetLiabType(type) ||
-        xaccAccountIsEquityType(type))
-        return TRUE;
-    else
-        return FALSE;
-}
-
 /* Select the list of accounts to show in the tree */
 static void
 gnc_payment_set_account_types (GncTreeViewAccount *tree)
@@ -840,7 +831,7 @@ gnc_payment_set_account_types (GncTreeViewAccount *tree)
     gnc_tree_view_account_get_view_info (tree, &avi);
 
     for (i = 0; i < NUM_ACCOUNT_TYPES; i++)
-        avi.include_type[i] = AccountTypeOkForPayments (i);
+        avi.include_type[i] = gncBusinessIsPaymentAcctType (i);
 
     gnc_tree_view_account_set_view_info (tree, &avi);
 }
@@ -1151,67 +1142,11 @@ gnc_ui_payment_new (GncOwner *owner, QofBook *book)
     return gnc_ui_payment_new_with_invoice (owner, book, NULL);
 }
 
-// ////////////////////////////////////////////////////////////
-static void increment_if_asset_account (gpointer data,
-                                        gpointer user_data)
-{
-    int *r = user_data;
-    const Split *split = data;
-    const Account *account = xaccSplitGetAccount(split);
-    if (AccountTypeOkForPayments(xaccAccountGetType (account)))
-        ++(*r);
-}
-static int countAssetAccounts(SplitList* slist)
-{
-    int result = 0;
-    g_list_foreach(slist, &increment_if_asset_account, &result);
-    return result;
-}
-
-static gint predicate_is_asset_account(gconstpointer a,
-                                       gconstpointer user_data)
-{
-    const Split *split = a;
-    const Account *account = xaccSplitGetAccount(split);
-    if (AccountTypeOkForPayments(xaccAccountGetType(account)))
-        return 0;
-    else
-        return -1;
-}
-static gint predicate_is_apar_account(gconstpointer a,
-                                      gconstpointer user_data)
-{
-    const Split *split = a;
-    const Account *account = xaccSplitGetAccount(split);
-    if (xaccAccountIsAPARType(xaccAccountGetType(account)))
-        return 0;
-    else
-        return -1;
-}
-static Split *getFirstAssetAccountSplit(SplitList* slist)
-{
-    GList *r = g_list_find_custom(slist, NULL, &predicate_is_asset_account);
-    if (r)
-        return r->data;
-    else
-        return NULL;
-}
-static Split *getFirstAPARAccountSplit(SplitList* slist)
-{
-    GList *r = g_list_find_custom(slist, NULL, &predicate_is_apar_account);
-    if (r)
-        return r->data;
-    else
-        return NULL;
-}
-
 // ///////////////
 
 gboolean gnc_ui_payment_is_customer_payment(const Transaction *txn)
 {
-    SplitList *slist;
     gboolean result = TRUE;
-
     Split *assetaccount_split;
     gnc_numeric amount;
 
@@ -1220,17 +1155,17 @@ gboolean gnc_ui_payment_is_customer_payment(const Transaction *txn)
 
     // We require the txn to have one split in an A/R or A/P account.
 
-    slist = xaccTransGetSplitList(txn);
-    if (!slist)
+    if (!xaccTransGetSplitList(txn))
         return result;
-    if (countAssetAccounts(slist) == 0)
+    assetaccount_split = xaccTransGetFirstPaymentAcctSplit(txn);
+    if (!assetaccount_split)
     {
         g_message("No asset splits in txn \"%s\"; cannot use this for assigning a payment.",
                   xaccTransGetDescription(txn));
         return result;
     }
 
-    assetaccount_split = getFirstAssetAccountSplit(slist);
+    assetaccount_split = xaccTransGetFirstPaymentAcctSplit(txn);
     amount = xaccSplitGetValue(assetaccount_split);
     result = gnc_numeric_positive_p(amount); // positive amounts == customer
     //g_message("Amount=%s", gnc_numeric_to_string(amount));
@@ -1241,8 +1176,6 @@ gboolean gnc_ui_payment_is_customer_payment(const Transaction *txn)
 
 PaymentWindow * gnc_ui_payment_new_with_txn (GncOwner *owner, Transaction *txn)
 {
-    SplitList *slist;
-
     Split *assetaccount_split;
     Split *postaccount_split;
     gnc_numeric amount;
@@ -1253,23 +1186,22 @@ PaymentWindow * gnc_ui_payment_new_with_txn (GncOwner *owner, Transaction *txn)
 
     // We require the txn to have one split in an Asset account.
 
-    slist = xaccTransGetSplitList(txn);
-    if (!slist)
+    if (!xaccTransGetSplitList(txn))
         return NULL;
-    if (countAssetAccounts(slist) == 0)
+    assetaccount_split = xaccTransGetFirstPaymentAcctSplit(txn);
+    if (!assetaccount_split)
     {
         g_message("No asset splits in txn \"%s\"; cannot use this for assigning a payment.",
                   xaccTransGetDescription(txn));
         return NULL;
     }
 
-    assetaccount_split = getFirstAssetAccountSplit(slist);
-    postaccount_split = getFirstAPARAccountSplit(slist); // watch out: Might be NULL
+    postaccount_split = xaccTransGetFirstAPARAcctSplit(txn); // watch out: Might be NULL
     amount = xaccSplitGetValue(assetaccount_split);
 
     pw = gnc_ui_payment_new(owner,
                             qof_instance_get_book(QOF_INSTANCE(txn)));
-    g_assert(assetaccount_split); // we can rely on this because of the countAssetAccounts() check above
+    g_assert(assetaccount_split); // we can rely on this because of the check above
     g_debug("Amount=%s", gnc_numeric_to_string(amount));
 
     // Fill in the values from the given txn

src/engine/Transaction.c

@@ -60,6 +60,7 @@ struct timeval
 #include <gnc-gdate-utils.h>
 #include "SchedXaction.h"
 #include "qofbackend-p.h"
+#include "gncBusiness.h"
 
 /* Notes about xaccTransBeginEdit(), xaccTransCommitEdit(), and
  *  xaccTransRollback():
@@ -2141,6 +2142,28 @@ xaccTransGetSplitList (const Transaction *trans)
     return trans ? trans->splits : NULL;
 }
 
+Split *xaccTransGetFirstPaymentAcctSplit(const Transaction *trans)
+{
+    FOR_EACH_SPLIT (trans,
+                    const Account *account = xaccSplitGetAccount(s);
+                    if (gncBusinessIsPaymentAcctType(xaccAccountGetType(account)))
+                        return s;
+                   );
+
+    return NULL;
+}
+
+Split *xaccTransGetFirstAPARAcctSplit(const Transaction *trans)
+{
+    FOR_EACH_SPLIT (trans,
+                    const Account *account = xaccSplitGetAccount(s);
+                    if (xaccAccountIsAPARType(xaccAccountGetType(account)))
+                        return s;
+                   );
+
+    return NULL;
+}
+
 int
 xaccTransCountSplits (const Transaction *trans)
 {

src/engine/Transaction.h

@@ -370,6 +370,21 @@ int xaccTransGetSplitIndex(const Transaction *trans, const Split *split);
 SplitList *   xaccTransGetSplitList (const Transaction *trans);
 gboolean      xaccTransStillHasSplit(const Transaction *trans, const Split *s);
 
+/** The xaccTransGetFirstPaymentAcctSplit() method returns a pointer to the first
+    split in this transaction that belongs to an account which is considered a
+    valid account for business payments.
+    @param trans The transaction
+
+    If there is no such split in the transaction NULL will be returned. */
+Split *       xaccTransGetFirstPaymentAcctSplit (const Transaction *trans);
+
+/** The xaccTransGetFirstPaymentAcctSplit() method returns a pointer to the first
+    split in this transaction that belongs to an AR or AP account.
+    @param trans The transaction
+
+    If there is no such split in the transaction NULL will be returned. */
+Split *       xaccTransGetFirstAPARAcctSplit (const Transaction *trans);
+
 /** Set the transaction to be ReadOnly by setting a non-NULL value as "reason".
  *
  * FIXME: If "reason" is NULL, this function does nothing, instead of removing the

src/engine/gncBusiness.c

@@ -88,3 +88,12 @@ GList * gncBusinessGetOwnerList (QofBook *book, const char *type_name,
 
     return data.result;
 }
+
+gboolean gncBusinessIsPaymentAcctType (GNCAccountType type)
+{
+    if (xaccAccountIsAssetLiabType(type) ||
+        xaccAccountIsEquityType(type))
+        return TRUE;
+    else
+        return FALSE;
+}

src/engine/gncBusiness.h

@@ -36,6 +36,7 @@
 
 #include <glib.h>
 #include "qof.h"
+#include "Account.h"
 
 /* @deprecated backwards-compat definitions */
 #define GNC_BILLTERM_MODULE_NAME GNC_ID_BILLTERM
@@ -80,5 +81,10 @@ typedef GList OwnerList;
 OwnerList * gncBusinessGetOwnerList (QofBook *book, QofIdTypeConst type_name,
                                      gboolean all_including_inactive);
 
+/** Returns whether the given account type is a valid type to use in
+ * business payments. Currently payments are allowed to/from assets,
+ * liabilities and equity accounts. */
+gboolean gncBusinessIsPaymentAcctType (GNCAccountType type);
+
 
 #endif /* GNC_BUSINESS_H_ */