gncInvoice.c

/********************************************************************\
 * gncInvoice.c -- the Core Business Invoice                        *
 *                                                                  *
 * This program is free software; you can redistribute it and/or    *
 * modify it under the terms of the GNU General Public License as   *
 * published by the Free Software Foundation; either version 2 of   *
 * the License, or (at your option) any later version.              *
 *                                                                  *
 * This program is distributed in the hope that it will be useful,  *
 * but WITHOUT ANY WARRANTY; without even the implied warranty of   *
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the    *
 * GNU General Public License for more details.                     *
 *                                                                  *
 * You should have received a copy of the GNU General Public License*
 * along with this program; if not, contact:                        *
 *                                                                  *
 * Free Software Foundation           Voice:  +1-617-542-5942       *
 * 51 Franklin Street, Fifth Floor    Fax:    +1-617-542-2652       *
 * Boston, MA  02110-1301,  USA       gnu@gnu.org                   *
 *                                                                  *
\********************************************************************/

/*
 * Copyright (C) 2001,2002,2006 Derek Atkins
 * Copyright (C) 2003 Linas Vepstas <linas@linas.org>
 * Copyright (c) 2005 Neil Williams <linux@codehelp.co.uk>
 * Author: Derek Atkins <warlord@MIT.EDU>
 */

#include <config.h>

#include <inttypes.h>
#include <glib.h>
#include <glib/gi18n.h>
#include <qofinstance-p.h>

#include "Transaction.h"
#include "Account.h"
#include "gncBillTermP.h"
#include "gncEntry.h"
#include "gncEntryP.h"
#include "gnc-features.h"
#include "gncJobP.h"
#include "gncInvoice.h"
#include "gncInvoiceP.h"
#include "gncOwnerP.h"
#include "engine-helpers.h"

struct _gncInvoice
{
    QofInstance   inst;

    const char    *id;
    const char    *notes;
    gboolean      active;

    const char    *billing_id;
    char          *printname;
    GncBillTerm   *terms;
    GList         *entries;
    GList         *prices;
    GncOwner      owner;
    GncOwner      billto;
    GncJob        *job;
    time64        date_opened;
    time64        date_posted;

    gnc_numeric   to_charge_amount;

    gnc_commodity *currency;

    Account       *posted_acc;
    Transaction   *posted_txn;
    GNCLot        *posted_lot;
};

struct _gncInvoiceClass
{
    QofInstanceClass parent_class;
};

static QofLogModule log_module = GNC_MOD_BUSINESS;

#define _GNC_MOD_NAME     GNC_ID_INVOICE

#define GNC_INVOICE_IS_CN "credit-note"
#define GNC_INVOICE_DOCLINK "assoc_uri" // this is the old name for the document link, kept for compatibility

#define SET_STR(obj, member, str) { \
    if (!g_strcmp0 (member, str)) return; \
    gncInvoiceBeginEdit (obj); \
    CACHE_REPLACE (member, str); \
    }

static void mark_invoice (GncInvoice *invoice);
static void
mark_invoice (GncInvoice *invoice)
{
    qof_instance_set_dirty (&invoice->inst);
    qof_event_gen (&invoice->inst, QOF_EVENT_MODIFY, NULL);
}

QofBook * gncInvoiceGetBook (GncInvoice *x)
{
    return qof_instance_get_book (QOF_INSTANCE(x));
}

/* ================================================================== */

enum
{
    PROP_0,
//  PROP_ID,            /* Table */
//  PROP_DATE_OPENED,   /* Table */
//  PROP_DATE_POSTED,   /* Table */
    PROP_NOTES,         /* Table */
//  PROP_ACTIVE,        /* Table */
//  PROP_CURRENCY,      /* Table */
//  PROP_OWNER_TYPE,    /* Table */
//  PROP_OWNER,         /* Table */
//  PROP_TERMS,         /* Table */
//  PROP_BILLING_ID,    /* Table */
//  PROP_POST_TXN,      /* Table */
//  PROP_POST_LOT,      /* Table */
//  PROP_POST_ACCOUNT,  /* Table */
//  PROP_BILLTO_TYPE,   /* Table */
//  PROP_BILLTO,        /* Table */
//  PROP_CHARGE_AMOUNT, /* Table, (numeric) */
};

/* GObject Initialization */
G_DEFINE_TYPE(GncInvoice, gnc_invoice, QOF_TYPE_INSTANCE)

static void
gnc_invoice_init (GncInvoice* inv)
{
    inv->date_posted = INT64_MAX;
    inv->date_opened = INT64_MAX;
}

static void
gnc_invoice_dispose (GObject *invp)
{
    G_OBJECT_CLASS(gnc_invoice_parent_class)->dispose(invp);
}

static void
gnc_invoice_finalize (GObject* invp)
{
    G_OBJECT_CLASS(gnc_invoice_parent_class)->finalize(invp);
}

static void
gnc_invoice_get_property (GObject         *object,
                          guint            prop_id,
                          GValue          *value,
                          GParamSpec      *pspec)
{
    GncInvoice *inv;

    g_return_if_fail (GNC_IS_INVOICE(object));

    inv = GNC_INVOICE(object);
    switch (prop_id)
    {
    case PROP_NOTES:
        g_value_set_string (value, inv->notes);
        break;
    default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
        break;
    }
}

static void
gnc_invoice_set_property (GObject         *object,
                          guint            prop_id,
                          const GValue    *value,
                          GParamSpec      *pspec)
{
    GncInvoice *inv;

    g_return_if_fail (GNC_IS_INVOICE(object));

    inv = GNC_INVOICE(object);
    g_assert (qof_instance_get_editlevel (inv));

    switch (prop_id)
    {
    case PROP_NOTES:
        gncInvoiceSetNotes (inv, g_value_get_string (value));
        break;
    default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
        break;
    }
}

static gchar*
impl_get_display_name (const QofInstance* inst)
{
    GncInvoice* inv;
    QofInstance* owner;
    gchar* s;

    g_return_val_if_fail (inst != NULL, FALSE);
    g_return_val_if_fail (GNC_IS_INVOICE(inst), FALSE);

    inv = GNC_INVOICE(inst);
    owner = qofOwnerGetOwner (&inv->owner);
    if (owner != NULL)
    {
        gchar* display_name;

        display_name = qof_instance_get_display_name (owner);
        s = g_strdup_printf ("Invoice %s (%s)", inv->id, display_name);
        g_free (display_name);
    }
    else
    {
        s = g_strdup_printf ("Invoice %s", inv->id);
    }

    return s;
}

static gboolean
impl_refers_to_object (const QofInstance* inst, const QofInstance* ref)
{
    GncInvoice* inv;

    g_return_val_if_fail (inst != NULL, FALSE);
    g_return_val_if_fail (GNC_IS_INVOICE(inst), FALSE);

    inv = GNC_INVOICE(inst);

    if (GNC_IS_BILLTERM(ref))
    {
        return (inv->terms == GNC_BILLTERM(ref));
    }
    else if (GNC_IS_JOB(ref))
    {
        return (inv->job == GNC_JOB(ref));
    }
    else if (GNC_IS_COMMODITY(ref))
    {
        return (inv->currency == GNC_COMMODITY(ref));
    }
    else if (GNC_IS_ACCOUNT(ref))
    {
        return (inv->posted_acc == GNC_ACCOUNT(ref));
    }
    else if (GNC_IS_TRANSACTION(ref))
    {
        return (inv->posted_txn == GNC_TRANSACTION(ref));
    }
    else if (GNC_IS_LOT(ref))
    {
        return (inv->posted_lot == GNC_LOT(ref));
    }

    return FALSE;
}

static GList*
impl_get_typed_referring_object_list (const QofInstance* inst, const QofInstance* ref)
{
    if (!GNC_IS_BILLTERM(ref) && !GNC_IS_JOB(ref) && !GNC_IS_COMMODITY(ref) && !GNC_IS_ACCOUNT(ref)
            && !GNC_IS_TRANSACTION(ref) && !GNC_IS_LOT(ref))
    {
        return NULL;
    }

    return qof_instance_get_referring_object_list_from_collection (qof_instance_get_collection (inst), ref);
}

static void
gnc_invoice_class_init (GncInvoiceClass *klass)
{
    GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
    QofInstanceClass* qof_class = QOF_INSTANCE_CLASS(klass);

    gobject_class->dispose = gnc_invoice_dispose;
    gobject_class->finalize = gnc_invoice_finalize;
    gobject_class->set_property = gnc_invoice_set_property;
    gobject_class->get_property = gnc_invoice_get_property;

    qof_class->get_display_name = impl_get_display_name;
    qof_class->refers_to_object = impl_refers_to_object;
    qof_class->get_typed_referring_object_list = impl_get_typed_referring_object_list;

    g_object_class_install_property
    (gobject_class,
     PROP_NOTES,
     g_param_spec_string ("notes",
                          "Invoice Notes",
                          "The invoice notes is an arbitrary string "
                          "assigned by the user to provide notes regarding "
                          "this invoice.",
                          NULL,
                          G_PARAM_READWRITE));
}

/* Create/Destroy Functions */
GncInvoice *gncInvoiceCreate (QofBook *book)
{
    GncInvoice *invoice;

    if (!book) return NULL;

    invoice = g_object_new (GNC_TYPE_INVOICE, NULL);
    qof_instance_init_data (&invoice->inst, _GNC_MOD_NAME, book);

    invoice->id = CACHE_INSERT ("");
    invoice->notes = CACHE_INSERT ("");
    invoice->billing_id = CACHE_INSERT ("");

    invoice->billto.type = GNC_OWNER_CUSTOMER;
    invoice->active = TRUE;

    invoice->to_charge_amount = gnc_numeric_zero ();

    qof_event_gen (&invoice->inst, QOF_EVENT_CREATE, NULL);

    return invoice;
}

GncInvoice *gncInvoiceCopy (const GncInvoice *from)
{
    GncInvoice *invoice;
    QofBook* book;
    GList *node;
    GValue v = G_VALUE_INIT;

    g_assert (from);
    book = qof_instance_get_book (from);
    g_assert (book);

    invoice = g_object_new (GNC_TYPE_INVOICE, NULL);
    qof_instance_init_data (&invoice->inst, _GNC_MOD_NAME, book);

    gncInvoiceBeginEdit (invoice);

    invoice->id = CACHE_INSERT (from->id);
    invoice->notes = CACHE_INSERT (from->notes);
    invoice->billing_id = CACHE_INSERT (from->billing_id);
    invoice->active = from->active;

    qof_instance_get_kvp (QOF_INSTANCE (from), &v, 1, GNC_INVOICE_IS_CN);
    if (G_VALUE_HOLDS_INT64 (&v))
         qof_instance_set_kvp (QOF_INSTANCE (invoice), &v, 1, GNC_INVOICE_IS_CN);
    g_value_unset (&v);

    invoice->terms = from->terms;
    gncBillTermIncRef (invoice->terms);

    gncOwnerCopy (&from->billto, &invoice->billto);
    gncOwnerCopy (&from->owner, &invoice->owner);
    invoice->job = from->job; // FIXME: Need IncRef or similar here?!?

    invoice->to_charge_amount = from->to_charge_amount;
    invoice->date_opened = from->date_opened;

    // Oops. Do not forget to copy the pointer to the correct currency here.
    invoice->currency = from->currency;

    gncInvoiceSetDocLink (invoice, gncInvoiceGetDocLink (from));

    // Copy all invoice->entries
    for (node = from->entries; node; node = node->next)
    {
        GncEntry *from_entry = node->data;
        GncEntry *to_entry = gncEntryCreate (book);
        gncEntryCopy (from_entry, to_entry, FALSE);

        switch (gncInvoiceGetOwnerType (invoice))
        {
        case GNC_OWNER_VENDOR:
        case GNC_OWNER_EMPLOYEE:
            // this is a vendor bill, or an expense voucher
            gncBillAddEntry (invoice, to_entry);
            break;
        case GNC_OWNER_CUSTOMER:
        default:
            // this is an invoice
            gncInvoiceAddEntry (invoice, to_entry);
            break;
        }
    }

    // FIXME: The prices are not (yet) copied; is this a problem?

    // Posted-date and the posted Txn is intentionally not copied; the
    // copy isn't "posted" but needs to be posted by the user.
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);

    return invoice;
}

void gncInvoiceDestroy (GncInvoice *invoice)
{
    if (!invoice) return;
    qof_instance_set_destroying (invoice, TRUE);
    gncInvoiceCommitEdit (invoice);
}

static void gncInvoiceFree (GncInvoice *invoice)
{
    if (!invoice) return;

    qof_event_gen (&invoice->inst, QOF_EVENT_DESTROY, NULL);

    CACHE_REMOVE (invoice->id);
    CACHE_REMOVE (invoice->notes);
    CACHE_REMOVE (invoice->billing_id);
    g_list_free (invoice->entries);
    g_list_free (invoice->prices);

    if (invoice->printname)
        g_free (invoice->printname);

    if (!qof_book_shutting_down (qof_instance_get_book (QOF_INSTANCE(invoice))))
    {
        if (invoice->terms)
            gncBillTermDecRef (invoice->terms);
    }

    /* qof_instance_release (&invoice->inst); */
    g_object_unref (invoice);
}

/* ================================================================== */
/* Set Functions */

void gncInvoiceSetID (GncInvoice *invoice, const char *id)
{
    if (!invoice || !id) return;
    SET_STR (invoice, invoice->id, id);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetOwner (GncInvoice *invoice, GncOwner *owner)
{
    if (!invoice || !owner) return;
    if (gncOwnerEqual (&invoice->owner, owner)) return;
    gncInvoiceBeginEdit (invoice);
    gncOwnerCopy (owner, &invoice->owner);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

static void
qofInvoiceSetOwner (GncInvoice *invoice, QofInstance *ent)
{
    if (!invoice || !ent)
    {
        return;
    }
    gncInvoiceBeginEdit (invoice);
    qofOwnerSetEntity (&invoice->owner, ent);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

static void
qofInvoiceSetBillTo (GncInvoice *invoice, QofInstance *ent)
{
    if (!invoice || !ent)
    {
        return;
    }
    gncInvoiceBeginEdit (invoice);
    qofOwnerSetEntity (&invoice->billto, ent);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetDateOpenedGDate (GncInvoice *invoice, const GDate *date)
{
    g_assert (date);
    gncInvoiceSetDateOpened(invoice, time64CanonicalDayTime (gdate_to_time64 (*date)));
}

void gncInvoiceSetDateOpened (GncInvoice *invoice, time64 date)
{
    if (!invoice) return;
    if (date == invoice->date_opened) return;
    gncInvoiceBeginEdit (invoice);
    invoice->date_opened = date;
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetDatePosted (GncInvoice *invoice, time64 date)
{
    if (!invoice) return;
    if (date == invoice->date_posted) return;
    gncInvoiceBeginEdit (invoice);
    invoice->date_posted = date;
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetTerms (GncInvoice *invoice, GncBillTerm *terms)
{
    if (!invoice) return;
    if (invoice->terms == terms) return;
    gncInvoiceBeginEdit (invoice);
    if (invoice->terms)
        gncBillTermDecRef (invoice->terms);
    invoice->terms = terms;
    if (invoice->terms)
        gncBillTermIncRef (invoice->terms);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetBillingID (GncInvoice *invoice, const char *billing_id)
{
    if (!invoice) return;
    SET_STR (invoice, invoice->billing_id, billing_id);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetNotes (GncInvoice *invoice, const char *notes)
{
    if (!invoice || !notes) return;
    SET_STR (invoice, invoice->notes, notes);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetDocLink (GncInvoice *invoice, const char *doclink)
{
    if (!invoice || !doclink) return;

    gncInvoiceBeginEdit (invoice);

    if (doclink[0] == '\0')
    {
        qof_instance_set_kvp (QOF_INSTANCE (invoice), NULL, 1, GNC_INVOICE_DOCLINK);
    }
    else
    {
        GValue v = G_VALUE_INIT;
        g_value_init (&v, G_TYPE_STRING);
        g_value_set_static_string (&v, doclink);
        qof_instance_set_kvp (QOF_INSTANCE (invoice), &v, 1, GNC_INVOICE_DOCLINK);
        g_value_unset (&v);
    }
    qof_instance_set_dirty (QOF_INSTANCE(invoice));
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetActive (GncInvoice *invoice, gboolean active)
{
    if (!invoice) return;
    if (invoice->active == active) return;
    gncInvoiceBeginEdit (invoice);
    invoice->active = active;
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetIsCreditNote (GncInvoice *invoice, gboolean credit_note)
{
     GValue v = G_VALUE_INIT;
    if (!invoice) return;
    gncInvoiceBeginEdit (invoice);
    g_value_init (&v, G_TYPE_INT64);
    g_value_set_int64 (&v, credit_note ? 1 : 0);
    qof_instance_set_kvp (QOF_INSTANCE (invoice), &v, 1, GNC_INVOICE_IS_CN);
    g_value_unset (&v);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);

    /* If this is a credit note, set a feature flag for it in the book
     * This will prevent older GnuCash versions that don't support
     * credit notes to open this file. */
    if (credit_note)
        gnc_features_set_used (gncInvoiceGetBook (invoice), GNC_FEATURE_CREDIT_NOTES);
}

void gncInvoiceSetCurrency (GncInvoice *invoice, gnc_commodity *currency)
{
    if (!invoice || !currency) return;
    if (invoice->currency &&
            gnc_commodity_equal (invoice->currency, currency))
        return;
    gncInvoiceBeginEdit (invoice);
    invoice->currency = currency;
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetBillTo (GncInvoice *invoice, GncOwner *billto)
{
    if (!invoice || !billto) return;
    if (gncOwnerEqual (&invoice->billto, billto)) return;

    gncInvoiceBeginEdit (invoice);
    gncOwnerCopy (billto, &invoice->billto);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetToChargeAmount (GncInvoice *invoice, gnc_numeric amount)
{
    if (!invoice) return;
    if (gnc_numeric_equal (invoice->to_charge_amount, amount)) return;
    gncInvoiceBeginEdit (invoice);
    invoice->to_charge_amount = amount;
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetPostedTxn (GncInvoice *invoice, Transaction *txn)
{
    if (!invoice) return;
    g_return_if_fail (invoice->posted_txn == NULL);

    gncInvoiceBeginEdit (invoice);
    invoice->posted_txn = txn;
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetPostedLot (GncInvoice *invoice, GNCLot *lot)
{
    if (!invoice) return;
    g_return_if_fail (invoice->posted_lot == NULL);

    gncInvoiceBeginEdit (invoice);
    invoice->posted_lot = lot;
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceSetPostedAcc (GncInvoice *invoice, Account *acc)
{
    if (!invoice) return;
    g_return_if_fail (invoice->posted_acc == NULL);

    gncInvoiceBeginEdit (invoice);
    invoice->posted_acc = acc;
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceAddEntry (GncInvoice *invoice, GncEntry *entry)
{
    GncInvoice *old;

    g_assert (invoice);
    g_assert (entry);
    if (!invoice || !entry) return;

    old = gncEntryGetInvoice (entry);
    if (old == invoice) return; /* I already own this one */
    if (old) gncInvoiceRemoveEntry (old, entry);

    gncInvoiceBeginEdit (invoice);
    gncEntrySetInvoice (entry, invoice);
    invoice->entries = g_list_insert_sorted (invoice->entries, entry,
                       (GCompareFunc)gncEntryCompare);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceRemoveEntry (GncInvoice *invoice, GncEntry *entry)
{
    if (!invoice || !entry) return;

    gncInvoiceBeginEdit (invoice);
    gncEntrySetInvoice (entry, NULL);
    invoice->entries = g_list_remove (invoice->entries, entry);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceAddPrice (GncInvoice *invoice, GNCPrice *price)
{
    GList *node;
    gnc_commodity *commodity;

    if (!invoice || !price) return;

    /* Keep only one price per commodity per invoice
     * So if a price was set previously remove it first */
    node = g_list_first (invoice->prices);
    commodity = gnc_price_get_commodity (price);
    while (node != NULL)
    {
        GNCPrice *curr = (GNCPrice*)node->data;
        if (gnc_commodity_equal (commodity, gnc_price_get_commodity (curr)))
            break;
        node = g_list_next (node);
    }

    gncInvoiceBeginEdit (invoice);
    if (node)
        invoice->prices = g_list_delete_link (invoice->prices, node);
    invoice->prices = g_list_prepend (invoice->prices, price);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncBillAddEntry (GncInvoice *bill, GncEntry *entry)
{
    GncInvoice *old;

    g_assert (bill);
    g_assert (entry);
    if (!bill || !entry) return;

    old = gncEntryGetBill (entry);
    if (old == bill) return;    /* I already own this one */
    if (old) gncBillRemoveEntry (old, entry);

    gncInvoiceBeginEdit (bill);
    gncEntrySetBill (entry, bill);
    bill->entries = g_list_insert_sorted (bill->entries, entry,
                                          (GCompareFunc)gncEntryCompare);
    mark_invoice (bill);
    gncInvoiceCommitEdit (bill);
}

void gncBillRemoveEntry (GncInvoice *bill, GncEntry *entry)
{
    if (!bill || !entry) return;

    gncInvoiceBeginEdit (bill);
    gncEntrySetBill (entry, NULL);
    bill->entries = g_list_remove (bill->entries, entry);
    mark_invoice (bill);
    gncInvoiceCommitEdit (bill);
}

void gncInvoiceSortEntries (GncInvoice *invoice)
{
    if (!invoice) return;
    invoice->entries = g_list_sort (invoice->entries,
                                   (GCompareFunc)gncEntryCompare);
    gncInvoiceBeginEdit (invoice);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);
}

void gncInvoiceRemoveEntries (GncInvoice *invoice)
{
    if (!invoice) return;

    // gnc{Bill,Invoice}RemoveEntry free the "entry" node.
    // Make sure to save "next" first.
    for (GList *next, *node = invoice->entries; node; node = next)
    {
        next = node->next;
        GncEntry *entry = node->data;

        switch (gncInvoiceGetOwnerType (invoice))
        {
        case GNC_OWNER_VENDOR:
        case GNC_OWNER_EMPLOYEE:
            // this is a vendor bill, or an expense voucher
            gncBillRemoveEntry (invoice, entry);
            break;
        case GNC_OWNER_CUSTOMER:
        default:
            // this is an invoice
            gncInvoiceRemoveEntry (invoice, entry);
            break;
        }

        /* If the entry is no longer referenced by any document,
         * remove it.
         */
        if (!(gncEntryGetInvoice (entry) ||
              gncEntryGetBill (entry) ||
              gncEntryGetOrder (entry)))
        {
            gncEntryBeginEdit (entry);
            gncEntryDestroy (entry);
        }
    }
}

/* ================================================================== */
/* Get Functions */

const char * gncInvoiceGetID (const GncInvoice *invoice)
{
    if (!invoice) return NULL;
    return invoice->id;
}

const GncOwner * gncInvoiceGetOwner (const GncInvoice *invoice)
{
    if (!invoice) return NULL;
    return &invoice->owner;
}

static QofInstance * qofInvoiceGetOwner (GncInvoice *invoice)
{
    GncOwner *owner;

    if (!invoice)
    {
        return NULL;
    }
    owner = &invoice->owner;
    return QOF_INSTANCE(owner);
}

static QofInstance * qofInvoiceGetBillTo (GncInvoice *invoice)
{
    GncOwner *billto;

    if (!invoice)
    {
        return NULL;
    }
    billto = &invoice->billto;
    return QOF_INSTANCE(billto);
}

time64 gncInvoiceGetDateOpened (const GncInvoice *invoice)
{
    if (!invoice) return INT64_MAX;
    return invoice->date_opened;
}

time64 gncInvoiceGetDatePosted (const GncInvoice *invoice)
{
    if (!invoice) return INT64_MAX;
    return invoice->date_posted;
}

time64 gncInvoiceGetDateDue (const GncInvoice *invoice)
{
    Transaction *txn;
    if (!invoice) return INT64_MAX;
    txn = gncInvoiceGetPostedTxn (invoice);
    if (!txn) return INT64_MAX;
    return xaccTransRetDateDue (txn);
}

GncBillTerm * gncInvoiceGetTerms (const GncInvoice *invoice)
{
    if (!invoice) return NULL;
    return invoice->terms;
}

const char * gncInvoiceGetBillingID (const GncInvoice *invoice)
{
    if (!invoice) return NULL;
    return invoice->billing_id;
}

const char * gncInvoiceGetNotes (const GncInvoice *invoice)
{
    if (!invoice) return NULL;
    return invoice->notes;
}

const char * gncInvoiceGetDocLink (const GncInvoice *invoice)
{
    if (!invoice) return NULL;

    GValue v = G_VALUE_INIT;
    qof_instance_get_kvp (QOF_INSTANCE(invoice), &v, 1, GNC_INVOICE_DOCLINK);
    const char *rv = G_VALUE_HOLDS_STRING(&v) ? g_value_get_string (&v) : NULL;
    g_value_unset (&v);

    return rv;
}

GncOwnerType gncInvoiceGetOwnerType (const GncInvoice *invoice)
{
    const GncOwner *owner;
    g_return_val_if_fail (invoice, GNC_OWNER_NONE);

    owner = gncOwnerGetEndOwner (gncInvoiceGetOwner (invoice));
    return (gncOwnerGetType (owner));
}

static gnc_numeric gncInvoiceSumTaxesInternal (AccountValueList *taxes)
{
    gnc_numeric tt = gnc_numeric_zero ();

    if (taxes)
    {
        GList *node;
        // Note we can use GNC_DENOM_AUTO below for rounding because
        // the values passed to this function should already have been rounded
        // to the desired denom and addition will just preserve it in that case.
        for (node = taxes; node; node=node->next)
        {
            GncAccountValue *acc_val = node->data;
            tt = gnc_numeric_add (tt, acc_val->value, GNC_DENOM_AUTO,
                                  GNC_HOW_DENOM_EXACT | GNC_HOW_RND_ROUND_HALF_UP);
        }
    }
    return tt;
}

static gnc_numeric gncInvoiceGetNetAndTaxesInternal (GncInvoice *invoice, gboolean use_value,
                                                     AccountValueList **taxes,
                                                     gboolean use_payment_type,
                                                     GncEntryPaymentType type)
{
    GList *node;
    gnc_numeric net_total = gnc_numeric_zero ();
    gboolean is_cust_doc, is_cn;
    AccountValueList *tv_list = NULL;
    int denom = gnc_commodity_get_fraction (gncInvoiceGetCurrency (invoice));

    g_return_val_if_fail (invoice, net_total);

    ENTER ("");
    /* Is the current document an invoice/credit note related to a customer or a vendor/employee ?
     * The GncEntry code needs to know to return the proper entry amounts
     */
    is_cust_doc = (gncInvoiceGetOwnerType (invoice) == GNC_OWNER_CUSTOMER);
    is_cn = gncInvoiceGetIsCreditNote (invoice);


    for (node = gncInvoiceGetEntries (invoice); node; node = node->next)
    {
        GncEntry *entry = node->data;
        gnc_numeric value;

        if (use_payment_type && gncEntryGetBillPayment (entry) != type)
            continue;

        if (use_value)
        {
            // Always use rounded net values to prevent creating imbalanced transactions on posting
            // https://bugs.gnucash.org/show_bug.cgi?id=628903
            value = gncEntryGetDocValue (entry, TRUE, is_cust_doc, is_cn);
            if (gnc_numeric_check (value) == GNC_ERROR_OK)
                net_total = gnc_numeric_add (net_total, value, GNC_DENOM_AUTO, GNC_HOW_DENOM_LCD);
            else
                PWARN ("bad value in our entry");
        }

        if (taxes)
        {
            AccountValueList *entrytaxes = gncEntryGetDocTaxValues (entry, is_cust_doc, is_cn);
            tv_list = gncAccountValueAddList (tv_list, entrytaxes);
            gncAccountValueDestroy (entrytaxes);
        }
    }

    if (taxes)
    {
        GList *node;
        // Round tax totals (accumulated per tax account) to prevent creating imbalanced transactions on posting
        // which could otherwise happen when using a tax table with multiple tax rates
        for (node = tv_list; node; node=node->next)
        {
            GncAccountValue *acc_val = node->data;
            acc_val->value = gnc_numeric_convert (acc_val->value,
                                  denom, GNC_HOW_DENOM_EXACT | GNC_HOW_RND_ROUND_HALF_UP);
        }
        *taxes = tv_list;
    }

    LEAVE ("%" PRId64 "/%" PRId64, net_total.num, net_total.denom);
    return net_total;
}

static gnc_numeric gncInvoiceGetTotalInternal (GncInvoice *invoice, gboolean use_value,
                                               gboolean use_tax,
                                               gboolean use_payment_type, GncEntryPaymentType type)
{
    AccountValueList *taxes;
    gnc_numeric total;

    if (!invoice) return gnc_numeric_zero ();

    ENTER ("");
    total = gncInvoiceGetNetAndTaxesInternal (invoice, use_value, use_tax? &taxes : NULL, use_payment_type, type);

    if (use_tax)
    {
        // Note we can use GNC_DENOM_AUTO below for rounding because
        // the values passed to this function should already have been rounded
        // to the desired denom and addition will just preserve it in that case.
        total = gnc_numeric_add (total, gncInvoiceSumTaxesInternal (taxes),
                                 GNC_DENOM_AUTO, GNC_HOW_DENOM_EXACT | GNC_HOW_RND_ROUND_HALF_UP);
        gncAccountValueDestroy (taxes);
    }
    LEAVE ("%" PRId64 "/%" PRId64, total.num, total.denom);
    return total;
}

gnc_numeric gncInvoiceGetTotal (GncInvoice *invoice)
{
    if (!invoice) return gnc_numeric_zero ();
    return gncInvoiceGetTotalInternal (invoice, TRUE, TRUE, FALSE, 0);
}

gnc_numeric gncInvoiceGetTotalSubtotal (GncInvoice *invoice)
{
    if (!invoice) return gnc_numeric_zero ();
    return gncInvoiceGetTotalInternal (invoice, TRUE, FALSE, FALSE, 0);
}

gnc_numeric gncInvoiceGetTotalTax (GncInvoice *invoice)
{
    if (!invoice) return gnc_numeric_zero ();
    return gncInvoiceGetTotalInternal (invoice, FALSE, TRUE, FALSE, 0);
}

gnc_numeric gncInvoiceGetTotalOf (GncInvoice *invoice, GncEntryPaymentType type)
{
    if (!invoice) return gnc_numeric_zero ();
    return gncInvoiceGetTotalInternal (invoice, TRUE, TRUE, TRUE, type);
}

AccountValueList *gncInvoiceGetTotalTaxList (GncInvoice *invoice)
{
    AccountValueList *taxes;
    if (!invoice) return NULL;

    gncInvoiceGetNetAndTaxesInternal (invoice, FALSE, &taxes, FALSE, 0);
    return taxes;
}

GList * gncInvoiceGetTypeListForOwnerType (GncOwnerType type)
{
    GList *type_list = NULL;
    switch (type)
    {
    case GNC_OWNER_CUSTOMER:
        type_list = g_list_append (type_list, GINT_TO_POINTER(GNC_INVOICE_CUST_INVOICE));
        type_list = g_list_append (type_list, GINT_TO_POINTER(GNC_INVOICE_CUST_CREDIT_NOTE));
        return type_list;
    case GNC_OWNER_VENDOR:
        type_list = g_list_append (type_list, GINT_TO_POINTER(GNC_INVOICE_VEND_INVOICE));
        type_list = g_list_append (type_list, GINT_TO_POINTER(GNC_INVOICE_VEND_CREDIT_NOTE));
        return type_list;
    case GNC_OWNER_EMPLOYEE:
        type_list = g_list_append (type_list, GINT_TO_POINTER(GNC_INVOICE_EMPL_INVOICE));
        type_list = g_list_append (type_list, GINT_TO_POINTER(GNC_INVOICE_EMPL_CREDIT_NOTE));
        return type_list;
    default:
        PWARN("Bad owner type, no invoices.");
        return NULL;
    }

}

GncInvoiceType gncInvoiceGetType (const GncInvoice *invoice)
{
    if (!invoice) return GNC_INVOICE_UNDEFINED;
    switch (gncInvoiceGetOwnerType (invoice))
    {
    case GNC_OWNER_CUSTOMER:
        return (gncInvoiceGetIsCreditNote (invoice) ?
                GNC_INVOICE_CUST_CREDIT_NOTE :
                GNC_INVOICE_CUST_INVOICE);
    case GNC_OWNER_VENDOR:
        return (gncInvoiceGetIsCreditNote (invoice) ?
                GNC_INVOICE_VEND_CREDIT_NOTE :
                GNC_INVOICE_VEND_INVOICE);
    case GNC_OWNER_EMPLOYEE:
        return (gncInvoiceGetIsCreditNote (invoice) ?
                GNC_INVOICE_EMPL_CREDIT_NOTE :
                GNC_INVOICE_EMPL_INVOICE);
    default:
        PWARN ("No invoice types defined for owner %d",
               gncInvoiceGetOwnerType (invoice));
        return GNC_INVOICE_UNDEFINED;
    }
}

const char * gncInvoiceGetTypeString (const GncInvoice *invoice)
{
    GncInvoiceType type = gncInvoiceGetType (invoice);
    switch (type)
    {
    case GNC_INVOICE_CUST_INVOICE:
        return _("Invoice");
    case GNC_INVOICE_VEND_INVOICE:
        return _("Bill");
    case GNC_INVOICE_EMPL_INVOICE:
        return _("Expense");
    case GNC_INVOICE_CUST_CREDIT_NOTE:
    case GNC_INVOICE_VEND_CREDIT_NOTE:
    case GNC_INVOICE_EMPL_CREDIT_NOTE:
        return _("Credit Note");
    default:
        PWARN("Unknown invoice type");
        return NULL;
    }
}

gnc_commodity * gncInvoiceGetCurrency (const GncInvoice *invoice)
{
    if (!invoice) return NULL;
    return invoice->currency;
}

GncOwner * gncInvoiceGetBillTo (GncInvoice *invoice)
{
    if (!invoice) return NULL;
    return &invoice->billto;
}

GNCLot * gncInvoiceGetPostedLot (const GncInvoice *invoice)
{
    if (!invoice) return NULL;
    return invoice->posted_lot;
}

Transaction * gncInvoiceGetPostedTxn (const GncInvoice *invoice)
{
    if (!invoice) return NULL;
    return invoice->posted_txn;
}

Account * gncInvoiceGetPostedAcc (const GncInvoice *invoice)
{
    if (!invoice) return NULL;
    return invoice->posted_acc;
}

gboolean gncInvoiceGetActive (const GncInvoice *invoice)
{
    if (!invoice) return FALSE;
    return invoice->active;
}

gboolean gncInvoiceGetIsCreditNote (const GncInvoice *invoice)
{
    GValue v = G_VALUE_INIT;
    gboolean retval;
    if (!invoice) return FALSE;
    qof_instance_get_kvp (QOF_INSTANCE(invoice), &v, 1, GNC_INVOICE_IS_CN);
    retval = G_VALUE_HOLDS_INT64(&v) && g_value_get_int64 (&v);
    g_value_unset (&v);
    return retval;
}


gnc_numeric gncInvoiceGetToChargeAmount (const GncInvoice *invoice)
{
    if (!invoice) return gnc_numeric_zero ();
    return invoice->to_charge_amount;
}

EntryList * gncInvoiceGetEntries (GncInvoice *invoice)
{
    if (!invoice) return NULL;
    return invoice->entries;
}

GNCPrice * gncInvoiceGetPrice (GncInvoice *invoice, gnc_commodity *commodity)
{
    GList *node = g_list_first (invoice->prices);

    while (node != NULL)
    {
        GNCPrice *curr = (GNCPrice*)node->data;

        if (gnc_commodity_equal (commodity, gnc_price_get_commodity (curr)))
            return curr;

        node = g_list_next (node);
    }

    return NULL;
}

static QofCollection*
qofInvoiceGetEntries (GncInvoice *invoice)
{
    QofCollection *entry_coll;
    GList         *list;
    QofInstance     *entry;

    entry_coll = qof_collection_new (GNC_ID_ENTRY);
    for (list = gncInvoiceGetEntries (invoice); list != NULL; list = list->next)
    {
        entry = QOF_INSTANCE(list->data);
        qof_collection_add_entity (entry_coll, entry);
    }
    return entry_coll;
}

static void
qofInvoiceEntryCB (QofInstance *ent, gpointer user_data)
{
    GncInvoice *invoice;

    invoice = (GncInvoice*)user_data;
    if (!invoice || !ent)
    {
        return;
    }
    switch (gncInvoiceGetOwnerType (invoice))
    {
    case GNC_OWNER_VENDOR:
    {
        gncBillAddEntry (invoice, (GncEntry*) ent);
        break;
    }
    default :
    {
        gncInvoiceAddEntry (invoice, (GncEntry*)ent);
        break;
    }
    }
}

static void
qofInvoiceSetEntries (GncInvoice *invoice, QofCollection *entry_coll)
{
    if (!entry_coll)
    {
        return;
    }
    if (0 == g_strcmp0 (qof_collection_get_type (entry_coll), GNC_ID_ENTRY))
    {
        qof_collection_foreach (entry_coll, qofInvoiceEntryCB, invoice);
    }
}

static GncJob*
qofInvoiceGetJob (const GncInvoice *invoice)
{
    if (!invoice)
    {
        return NULL;
    }
    return invoice->job;
}

static void
qofInvoiceSetJob (GncInvoice *invoice, GncJob *job)
{
    if (!invoice)
    {
        return;
    }
    invoice->job = job;
}

void
gncInvoiceDetachFromLot (GNCLot *lot)
{
    if (!lot) return;

    gnc_lot_begin_edit (lot);
    qof_instance_set (QOF_INSTANCE (lot), "invoice", NULL, NULL);
    gnc_lot_commit_edit (lot);
    gnc_lot_set_cached_invoice (lot, NULL);
}

void
gncInvoiceAttachToLot (GncInvoice *invoice, GNCLot *lot)
{
    GncGUID *guid;
    if (!invoice || !lot)
        return;

    if (invoice->posted_lot) return;    /* Cannot reset invoice's lot */
    guid  = (GncGUID*)qof_instance_get_guid (QOF_INSTANCE(invoice));
    gnc_lot_begin_edit (lot);
    qof_instance_set (QOF_INSTANCE (lot), "invoice", guid, NULL);
    gnc_lot_commit_edit (lot);
    gnc_lot_set_cached_invoice (lot, invoice);
    gncInvoiceSetPostedLot (invoice, lot);
}

GncInvoice * gncInvoiceGetInvoiceFromLot (GNCLot *lot)
{
    GncGUID *guid = NULL;
    QofBook *book;
    GncInvoice *invoice = NULL;

    if (!lot) return NULL;

    invoice = gnc_lot_get_cached_invoice (lot);
    if (!invoice)
    {
        book = gnc_lot_get_book (lot);
        qof_instance_get (QOF_INSTANCE(lot), "invoice", &guid, NULL);
        invoice = gncInvoiceLookup (book, guid);
        guid_free (guid);
        gnc_lot_set_cached_invoice (lot, invoice);
    }

    return invoice;
}

void
gncInvoiceAttachToTxn (GncInvoice *invoice, Transaction *txn)
{
    if (!invoice || !txn)
        return;

    if (invoice->posted_txn) return;    /* Cannot reset invoice's txn */

    xaccTransBeginEdit (txn);
    qof_instance_set (QOF_INSTANCE (txn), "invoice", //Prop INVOICE
              qof_instance_get_guid (QOF_INSTANCE (invoice)), NULL);
    xaccTransSetTxnType (txn, TXN_TYPE_INVOICE);
    xaccTransCommitEdit (txn);
    gncInvoiceSetPostedTxn (invoice, txn);
}

GncInvoice *
gncInvoiceGetInvoiceFromTxn (const Transaction *txn)
{
    GncGUID *guid = NULL;
    QofBook *book;
    GncInvoice *invoice = NULL;

    if (!txn) return NULL;

    book = xaccTransGetBook (txn);
    qof_instance_get (QOF_INSTANCE (txn), "invoice", &guid, NULL);
    invoice = gncInvoiceLookup (book, guid);
    guid_free (guid);
    return invoice;
}

gboolean gncInvoiceAmountPositive (const GncInvoice *invoice)
{
    switch (gncInvoiceGetType (invoice))
    {
    case GNC_INVOICE_CUST_INVOICE:
    case GNC_INVOICE_VEND_CREDIT_NOTE:
    case GNC_INVOICE_EMPL_CREDIT_NOTE:
        return TRUE;
    case GNC_INVOICE_CUST_CREDIT_NOTE:
    case GNC_INVOICE_VEND_INVOICE:
    case GNC_INVOICE_EMPL_INVOICE:
        return FALSE;
    case GNC_INVOICE_UNDEFINED:
    default:
        /* Should never be reached.
         * If it is, perhaps a new value is added to GncInvoiceType ? */
        g_assert_not_reached ();
        return FALSE;
    }
}

GHashTable *gncInvoiceGetForeignCurrencies (const GncInvoice *invoice)
{
    EntryList *entries_iter;
    gboolean is_cust_doc = (gncInvoiceGetOwnerType (invoice) == GNC_OWNER_CUSTOMER);
    gboolean is_cn = gncInvoiceGetIsCreditNote (invoice);
    GHashTable *amt_hash = g_hash_table_new_full (g_direct_hash, g_direct_equal,
                                                  NULL, g_free);
    ENTER ("");

    for (entries_iter = invoice->entries; entries_iter != NULL; entries_iter = g_list_next(entries_iter))
    {
        GncEntry *entry = (GncEntry*)entries_iter->data;
        Account *this_acc;
        gnc_commodity *account_currency;
        AccountValueList *tt_amts = NULL, *tt_iter;

        /* Check entry's account currency */
        this_acc = (is_cust_doc ? gncEntryGetInvAccount (entry) :
                    gncEntryGetBillAccount (entry));
        account_currency = xaccAccountGetCommodity (this_acc);

        if (this_acc &&
                !gnc_commodity_equal (gncInvoiceGetCurrency (invoice), account_currency))
        {
            gnc_numeric *curr_amt = (gnc_numeric*) g_hash_table_lookup (amt_hash, account_currency);
            gnc_numeric *entry_amt = (gnc_numeric*) g_new0 (gnc_numeric, 1);
            *entry_amt = gncEntryGetDocValue (entry, FALSE, is_cust_doc, is_cn);
            if (curr_amt)
                *entry_amt = gnc_numeric_add (*entry_amt, *curr_amt, GNC_DENOM_AUTO, GNC_HOW_RND_ROUND_HALF_UP);
            g_hash_table_insert (amt_hash, account_currency, entry_amt);
        }

        /* Check currencies of each account in the tax table linked
         * to the current entry */
        tt_amts = gncEntryGetDocTaxValues (entry, is_cust_doc, is_cn);

        if (!tt_amts)
            continue;

        for (tt_iter = tt_amts; tt_iter != NULL; tt_iter = g_list_next(tt_iter))
        {
            GncAccountValue *tt_amt_val = (GncAccountValue*)tt_iter->data;
            Account *tt_acc = tt_amt_val->account;
            gnc_commodity *tt_acc_currency = xaccAccountGetCommodity (tt_acc);

            if (tt_acc &&
                    !gnc_commodity_equal (gncInvoiceGetCurrency (invoice), tt_acc_currency))
            {
                gnc_numeric *curr_amt = (gnc_numeric*) g_hash_table_lookup (amt_hash, tt_acc_currency);
                gnc_numeric *tt_acc_amt = (gnc_numeric*) g_new0 (gnc_numeric, 1);
                *tt_acc_amt = tt_amt_val->value;
                if (curr_amt)
                    *tt_acc_amt = gnc_numeric_add (*tt_acc_amt, *curr_amt, GNC_DENOM_AUTO, GNC_HOW_RND_ROUND_HALF_UP);
                g_hash_table_insert (amt_hash, tt_acc_currency, tt_acc_amt);
            }
        }
        gncAccountValueDestroy (tt_amts);
    }

    LEAVE ("");
    return amt_hash;
}

static gboolean gncInvoicePostAddSplit (QofBook *book,
                                        Account *acc,
                                        Transaction *txn,
                                        gnc_numeric value,
                                        const gchar *memo,
                                        const gchar *type,
                                        GncInvoice *invoice)
{
    Split *split;

    ENTER ("");
    split = xaccMallocSplit (book);
    /* set action and memo? */

    xaccSplitSetMemo (split, memo);
    /* set per book option */
    gnc_set_num_action (NULL, split, gncInvoiceGetID (invoice), type);

    /* Need to insert this split into the account AND txn before
     * we set the Base Value.  Otherwise SetBaseValue complains
     * that we don't have an account and fails to set the value.
     */
    xaccAccountBeginEdit (acc);
    xaccAccountInsertSplit (acc, split);
    xaccAccountCommitEdit (acc);
    xaccTransAppendSplit (txn, split);

    /* General note on the split creations below:
     * Invoice and bill amounts are always stored as positive values in entries
     * So to convert them to proper splits, the amounts may have to be reverted
     * to have the proper effect on the account balance.
     * Credit notes have the opposite effect of invoices/bills, but their amounts
     * are stored as negative values as well. So to convert them into splits
     * they can be treated exactly the same as their invoice/bill counter parts.
     * The net effect is that the owner type is sufficient to determine whether a
     * value has to be reverted when converting an invoice/bill/cn amount to a split.
     */
    if (gnc_commodity_equal (xaccAccountGetCommodity (acc), invoice->currency))
    {
        xaccSplitSetBaseValue (split, value,
                               invoice->currency);
    }
    else
    {
        /*need to do conversion */
        GNCPrice *price = gncInvoiceGetPrice (invoice, xaccAccountGetCommodity (acc));

        if (price == NULL)
        {
            /*This is an error, which shouldn't even be able to happen.
              We can't really do anything sensible about it, and this is
                        a user-interface free zone so we can't try asking the user
              again either, have to return NULL*/
            PERR("Multiple commodities with no price.");
            LEAVE ("FALSE");
            return FALSE;
        }
        else
        {
            gnc_numeric converted_amount;
            xaccSplitSetValue (split, value);
            converted_amount = gnc_numeric_div (value, gnc_price_get_value (price), GNC_DENOM_AUTO, GNC_HOW_RND_ROUND_HALF_UP);
            DEBUG("converting from %f to %f\n", gnc_numeric_to_double (value), gnc_numeric_to_double (converted_amount));
            xaccSplitSetAmount (split, converted_amount);
        }
    }

    LEAVE ("TRUE");
    return TRUE;
}

Transaction * gncInvoicePostToAccount (GncInvoice *invoice, Account *acc,
                                       time64 post_date, time64 due_date,
                                       const char * memo, gboolean accumulatesplits,
                                       gboolean autopay)
{
    Transaction *txn;
    QofBook *book;
    GNCLot *lot = NULL;
    GList *iter;
    GList *splitinfo = NULL;
    gnc_numeric total;
    gboolean is_cust_doc;
    gboolean is_cn;
    const char *name, *type;
    char *lot_title;
    Account *ccard_acct = NULL;
    const GncOwner *owner;
    int denom = xaccAccountGetCommoditySCU (acc);
    AccountValueList *taxes;

    if (!invoice || !acc) return NULL;
    if (gncInvoiceIsPosted (invoice)) return NULL;

    ENTER ("");
    gncInvoiceBeginEdit (invoice);
    book = qof_instance_get_book (invoice);

    /* Stabilize the Billing Terms of this invoice */
    if (invoice->terms)
        gncInvoiceSetTerms (invoice,
                            gncBillTermReturnChild (invoice->terms, TRUE));

    /* GncEntry functions need to know if the invoice/credit note is for a customer or a vendor/employee. */
    is_cust_doc = (gncInvoiceGetOwnerType (invoice) == GNC_OWNER_CUSTOMER);
    is_cn = gncInvoiceGetIsCreditNote (invoice);

    /* Figure out if we need to separate out "credit-card" items */
    owner = gncOwnerGetEndOwner (gncInvoiceGetOwner (invoice));
    if (gncInvoiceGetOwnerType (invoice) == GNC_OWNER_EMPLOYEE)
        ccard_acct = gncEmployeeGetCCard (gncOwnerGetEmployee (owner));

    /* Create a new lot for this invoice */
    lot = gnc_lot_new (book);
    gncInvoiceAttachToLot (invoice, lot);
    gnc_lot_begin_edit (lot);

    type = gncInvoiceGetTypeString (invoice);

    /* Set the lot title */
    lot_title = g_strdup_printf ("%s %s", type, gncInvoiceGetID (invoice));
    gnc_lot_set_title (lot, lot_title);
    g_free (lot_title);

    /* Create a new transaction */
    txn = xaccMallocTransaction (book);
    xaccTransBeginEdit (txn);

    name = gncOwnerGetName (gncOwnerGetEndOwner (gncInvoiceGetOwner (invoice)));

    /* Set Transaction Description (Owner Name) , Num (invoice ID or type, based
     * on book option), Currency */
    xaccTransSetDescription (txn, name ? name : "");
    gnc_set_num_action (txn, NULL, gncInvoiceGetID (invoice), type);
    xaccTransSetCurrency (txn, invoice->currency);

    /* Entered and Posted at date */
    xaccTransSetDateEnteredSecs (txn, gnc_time (NULL));
    xaccTransSetDatePostedSecsNormalized (txn, post_date);
    gncInvoiceSetDatePosted (invoice, xaccTransRetDatePosted(txn));

    xaccTransSetDateDue (txn, due_date);

    /* Get invoice total and taxes. */
    total = gncInvoiceGetTotal (invoice);
    taxes = gncInvoiceGetTotalTaxList (invoice);
    /* The two functions above return signs relative to the document
     * We need to convert them to balance values before we can use them here
     * Note the odd construct comparing two booleans is to xor them
     * that is, only evaluate true if both are different.
     */
    if (is_cust_doc != is_cn)
    {
        GList *node;
        total = gnc_numeric_neg (total);
        for (node = taxes; node; node = node->next)
        {
            GncAccountValue *acc_val = node->data;
            acc_val->value = gnc_numeric_neg (acc_val->value);
        }
    }

    /* Iterate through the entries; sum up everything for each account.
     * then create the appropriate splits in this txn.
     */

    for (iter = gncInvoiceGetEntries (invoice); iter; iter = iter->next)
    {
        gnc_numeric value, tax;
        GncEntry * entry = iter->data;
        Account *this_acc;

        /* Stabilize the TaxTable in this entry */
        gncEntryBeginEdit (entry);
        if (is_cust_doc)
            gncEntrySetInvTaxTable
            (entry, gncTaxTableReturnChild (gncEntryGetInvTaxTable (entry), TRUE));
        else
        {
            gncEntrySetBillTaxTable
            (entry, gncTaxTableReturnChild (gncEntryGetBillTaxTable (entry), TRUE));

            /* If this is a bill, and the entry came from an invoice originally, copy the price */
            if (gncEntryGetBillable (entry))
            {
                /* We need to set the net price since it may be another tax rate for invoices than bills */
                gncEntrySetInvPrice (entry, gncEntryGetPrice (entry, FALSE, TRUE));
                gncEntrySetInvTaxIncluded (entry, FALSE);
            }
        }
        gncEntryCommitEdit (entry);

        /* Obtain the Entry's Value and TaxValues
           Note we use rounded values here and below to prevent creating an imbalanced transaction */
        value = gncEntryGetBalValue (entry, TRUE, is_cust_doc);
        tax   = gncEntryGetBalTaxValue (entry, TRUE, is_cust_doc);

        DEBUG ("Tax %" PRId64 "/%" PRId64 " on entry value %" PRId64 "/%" PRId64,
               tax.num, tax.denom, value.num, value.denom);
        /* add the value for the account split */
        this_acc = (is_cust_doc ? gncEntryGetInvAccount (entry) :
                    gncEntryGetBillAccount (entry));
        if (this_acc)
        {
            if (gnc_numeric_check (value) == GNC_ERROR_OK)
            {
                if (accumulatesplits)
                    splitinfo = gncAccountValueAdd (splitinfo, this_acc, value);
                    /* Adding to total in case of accumulatesplits will be deferred to later when each split is effectively added */
                else if (!gncInvoicePostAddSplit (book, this_acc, txn, value,
                                                  gncEntryGetDescription (entry),
                                                  type, invoice))
                {
                    /*This is an error, which shouldn't even be able to happen.
                      We can't really do anything sensible about it, and this is
                      a user-interface free zone so we can't try asking the user
                      again either, have to return NULL*/
                    PERR("Failed to add split %s", gncEntryGetDescription (entry));
                    LEAVE ("NULL");
                    return NULL;
                }

                /* If there is a credit-card account, and this is a CCard
                 * payment type, subtract it from the total, and instead
                 * create a split to the CC Acct with a memo of the entry
                 * description instead of the provided memo.  Note that the
                 * value reversal is the same as the post account.
                 *
                 * Note: we don't have to worry about the tax values --
                 * expense vouchers don't have them.
                 */
                if (ccard_acct && gncEntryGetBillPayment (entry) == GNC_PAYMENT_CARD)
                {
                    Split *split;

                    total = gnc_numeric_sub (total, value, denom,
                                             GNC_HOW_DENOM_EXACT | GNC_HOW_RND_ROUND_HALF_UP);

                    split = xaccMallocSplit (book);
                    xaccSplitSetMemo (split, gncEntryGetDescription (entry));
                    /* set action based on book option */
                    gnc_set_num_action (NULL, split, gncInvoiceGetID (invoice), type);
                    xaccAccountBeginEdit (ccard_acct);
                    xaccAccountInsertSplit (ccard_acct, split);
                    xaccAccountCommitEdit (ccard_acct);
                    xaccTransAppendSplit (txn, split);
                    xaccSplitSetBaseValue (split, gnc_numeric_neg (value),
                                           invoice->currency);

                }

            }
            else
                PWARN ("bad value in our entry");
        }

        /* check the taxes */
        if (gnc_numeric_check (tax) != GNC_ERROR_OK)
            PWARN ("bad tax in our entry");

    } /* for */


    /* now merge in the TaxValues */
    splitinfo = gncAccountValueAddList (splitinfo, taxes);
    gncAccountValueDestroy (taxes);

    /* Iterate through the splitinfo list and generate the splits */
    if (splitinfo)
        PINFO ("Processing Split List");
    for (iter = splitinfo; iter; iter = iter->next)
    {
        GncAccountValue *acc_val = iter->data;

        //gnc_numeric amt_rounded = gnc_numeric_convert(acc_val->value,
        //    denom, GNC_HOW_DENOM_EXACT | GNC_HOW_RND_ROUND_HALF_UP);
        if (!gncInvoicePostAddSplit (book, acc_val->account, txn, acc_val->value,
                                     memo, type, invoice))
        {
            /*This is an error, which shouldn't even be able to happen.
              We can't really do anything sensible about it, and this is
              a user-interface free zone so we can't try asking the user
              again either, have to return NULL*/
            PERR("Failed to add split %s, aborting accumulated splits.", memo);
            return NULL;
        }
    }

    /* If there is a ccard account, we may have an additional "to_card" payment.
     * we should make that now.
     */
    if (ccard_acct && !gnc_numeric_zero_p (invoice->to_charge_amount))
    {
        Split *split = xaccMallocSplit (book);

        /* To charge amount is stored in document value. We need balance value here
         * so convert if necessary. */
        gnc_numeric to_charge_bal_amount = (is_cn ? gnc_numeric_neg (invoice->to_charge_amount)
                                            : invoice->to_charge_amount);

        PINFO ("Process to_card payment split");
        /* Set memo. */
        xaccSplitSetMemo (split, _("Extra to Charge Card"));
        /* Set action based on book option */
        gnc_set_num_action (NULL, split, gncInvoiceGetID (invoice), type);

        xaccAccountBeginEdit (ccard_acct);
        xaccAccountInsertSplit (ccard_acct, split);
        xaccAccountCommitEdit (ccard_acct);
        xaccTransAppendSplit (txn, split);
        xaccSplitSetBaseValue (split, gnc_numeric_neg (to_charge_bal_amount),
                               invoice->currency);

        total = gnc_numeric_sub (total, to_charge_bal_amount, denom,
                                 GNC_HOW_DENOM_EXACT | GNC_HOW_RND_ROUND_HALF_UP);
    }

    /* Now create the Posted split (which is the opposite sign of the above splits) */
    {
        Split *split = xaccMallocSplit (book);

        PINFO ("Process to_card balancing split");
        /* Set memo */
        xaccSplitSetMemo (split, memo);
        /* Set action based on book option */
        gnc_set_num_action (NULL, split, gncInvoiceGetID (invoice), type);

        xaccAccountBeginEdit (acc);
        xaccAccountInsertSplit (acc, split);
        xaccAccountCommitEdit (acc);
        xaccTransAppendSplit (txn, split);
        xaccSplitSetBaseValue (split, gnc_numeric_neg (total),
                               invoice->currency);

        /* add this split to the lot */
        gnc_lot_add_split (lot, split);
    }

    /* Now attach this invoice to the txn and account */
    gncInvoiceAttachToTxn (invoice, txn);
    gncInvoiceSetPostedAcc (invoice, acc);

    xaccTransSetReadOnly (txn, _("Generated from an invoice. Try unposting the invoice."));
    xaccTransCommitEdit (txn);

    gncAccountValueDestroy (splitinfo);

    gnc_lot_commit_edit (lot);
    /* Not strictly necessary, since it was done by the Set calls
     * above, but good insurance. */
    DEBUG("Committing Invoice %s", invoice->id);
    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);

    /* If requested, attempt to automatically apply open payments
     * and reverse documents to this lot to close it (or at least
     * reduce its balance) */
    if (autopay)
        gncInvoiceAutoApplyPayments (invoice);

    LEAVE ("");
    return txn;
}

gboolean
gncInvoiceUnpost (GncInvoice *invoice, gboolean reset_tax_tables)
{
    Transaction *txn;
    GNCLot *lot;
    GList *lot_split_list, *lot_split_iter;

    if (!invoice) return FALSE;
    if (!gncInvoiceIsPosted (invoice)) return FALSE;

    txn = gncInvoiceGetPostedTxn (invoice);
    g_return_val_if_fail (txn, FALSE);

    lot = gncInvoiceGetPostedLot (invoice);
    g_return_val_if_fail (lot, FALSE);

    ENTER ("");
    /* Destroy the Posted Transaction */
    xaccTransClearReadOnly (txn);
    xaccTransBeginEdit (txn);
    xaccTransDestroy (txn);
    xaccTransCommitEdit (txn);

    /* Disconnect the lot from the invoice; re-attach to the invoice owner */
    gncInvoiceDetachFromLot (lot);
    gncOwnerAttachToLot (&invoice->owner, lot);

    /* Check if this invoice was linked to other lots (payments/inverse signed
     * invoices).
     * If this is the case, recreate the link transaction between all the remaining lots.
     *
     * Note that before GnuCash 2.6 payments were not stored in separate lots, but
     * always ended up in invoice lots when matched to an invoice. Over-payments
     * were copied to a new lot, to which later an invoice was added again and so on.
     * These over-payments were handled with automatic payment forward transactions.
     * You could consider these transactions to be links between lots as well, but
     * to avoid some unexpected behavior, these will not be altered here.
     */

    // Note: make a copy of the lot list here, when splits are deleted from the lot,
    //       the original list may be destroyed by the lot code.
    lot_split_list = g_list_copy (gnc_lot_get_split_list (lot));
    if (lot_split_list)
        PINFO ("Recreating link transactions for remaining lots");
    for (lot_split_iter = lot_split_list; lot_split_iter; lot_split_iter = lot_split_iter->next)
    {
        Split *split = lot_split_iter->data;
        GList *other_split_list, *list_iter;
        Transaction *other_txn = xaccSplitGetParent (split);
        GList *lot_list = NULL;

        /* Only work with transactions that link invoices and payments.
         * Note: this check also catches the possible case of NULL splits. */
        if (xaccTransGetTxnType (other_txn) != TXN_TYPE_LINK)
            continue;

        /* Save a list of lots this linking transaction linked to */
        other_split_list = xaccTransGetSplitList (other_txn);
        for (list_iter = other_split_list; list_iter; list_iter = list_iter->next)
        {
            Split *other_split = list_iter->data;
            GNCLot *other_lot = xaccSplitGetLot (other_split);

            /* Omit the lot we are about to delete */
            if (other_lot == lot)
                continue;

            lot_list = g_list_prepend (lot_list, other_lot);
        }
        /* Maintain original split order */
        lot_list = g_list_reverse (lot_list);

        /* Now remove this link transaction. */
        xaccTransClearReadOnly (other_txn);
        xaccTransBeginEdit (other_txn);
        xaccTransDestroy (other_txn);
        xaccTransCommitEdit (other_txn);

        /* Re-balance the saved lots as well as is possible */
        gncOwnerAutoApplyPaymentsWithLots (&invoice->owner, lot_list);

        /* If any of the saved lots has no more splits, then destroy it.
         * Otherwise if any has an invoice associated with it,
         * send it a modified event to reset its paid status */
        for (list_iter = lot_list; list_iter; list_iter = list_iter->next)
        {
            GNCLot *other_lot = list_iter->data;
            GncInvoice *other_invoice = gncInvoiceGetInvoiceFromLot (other_lot);

            if (!gnc_lot_count_splits (other_lot))
                gnc_lot_destroy (other_lot);
            else if (other_invoice)
                qof_event_gen (QOF_INSTANCE(other_invoice), QOF_EVENT_MODIFY, NULL);
        }
        g_list_free (lot_list);
    }
    g_list_free (lot_split_list);

    /* If the lot has no splits, then destroy it */
    if (!gnc_lot_count_splits (lot))
        gnc_lot_destroy (lot);

    /* Clear out the invoice posted information */
    gncInvoiceBeginEdit (invoice);

    invoice->posted_acc = NULL;
    invoice->posted_txn = NULL;
    invoice->posted_lot = NULL;
    invoice->date_posted = INT64_MAX;

    /* if we've been asked to reset the tax tables, then do so */
    if (reset_tax_tables)
    {
        gboolean is_cust_doc = (gncInvoiceGetOwnerType (invoice) == GNC_OWNER_CUSTOMER);
        GList *iter;

        for (iter = gncInvoiceGetEntries (invoice); iter; iter = iter->next)
        {
            GncEntry *entry = iter->data;

            gncEntryBeginEdit (entry);
            if (is_cust_doc)
                gncEntrySetInvTaxTable (entry,
                                        gncTaxTableGetParent (gncEntryGetInvTaxTable( entry)));
            else
                gncEntrySetBillTaxTable (entry,
                                         gncTaxTableGetParent (gncEntryGetBillTaxTable (entry)));
            gncEntryCommitEdit (entry);
        }
    }

    mark_invoice (invoice);
    gncInvoiceCommitEdit (invoice);

    LEAVE ("TRUE");

    return TRUE;
}

struct lotmatch
{
    const GncOwner *owner;
    gboolean positive_balance;
};

static gboolean
gnc_lot_match_owner_balancing (GNCLot *lot, gpointer user_data)
{
    struct lotmatch *lm = user_data;
    GncOwner owner_def;
    const GncOwner *owner;
    gnc_numeric balance = gnc_lot_get_balance (lot);

    /* Could (part of) this lot serve to balance the lot
     * for which this query was run ?*/
    if (lm->positive_balance == gnc_numeric_positive_p (balance))
        return FALSE;

    /* Is it ours? Either the lot owner or the lot invoice owner should match */
    if (!gncOwnerGetOwnerFromLot (lot, &owner_def))
    {
        const GncInvoice *invoice = gncInvoiceGetInvoiceFromLot (lot);
        if (!invoice)
            return FALSE;
        owner = gncOwnerGetEndOwner (gncInvoiceGetOwner (invoice));
    }
    else
        owner = gncOwnerGetEndOwner (&owner_def);

    return gncOwnerEqual (owner, lm->owner);
}

void gncInvoiceAutoApplyPayments (GncInvoice *invoice)
{
    GNCLot *inv_lot;
    Account *acct;
    const GncOwner *owner;
    GList *lot_list;
    struct lotmatch lm;

    /* General note: "paying" in this context means balancing
     * a lot, by linking opposite signed lots together. So below the term
     * "payment" can both mean a true payment or it can mean a document of
     * the opposite sign (invoice vs credit note). It just
     * depends on what type of document was given as parameter
     * to this function. */

    /* Payments can only be applied to posted invoices */
    g_return_if_fail (invoice);
    g_return_if_fail (invoice->posted_lot);

    inv_lot = invoice->posted_lot;
    acct = invoice->posted_acc;
    owner = gncOwnerGetEndOwner (gncInvoiceGetOwner (invoice));

    /* Find all lots whose balance (or part of their balance) could be
     * used to close this lot.
     * To be eligible, the lots have to have an opposite signed balance
     * and be for the same owner.
     * For example, for an invoice lot, payment lots and credit note lots
     * could be used. */
    lm.positive_balance =  gnc_numeric_positive_p (gnc_lot_get_balance (inv_lot));
    lm.owner = owner;
    lot_list = xaccAccountFindOpenLots (acct, gnc_lot_match_owner_balancing,
                                        &lm, NULL);

    lot_list = g_list_prepend (lot_list, inv_lot);
    gncOwnerAutoApplyPaymentsWithLots (owner, lot_list);
    g_list_free (lot_list);
}

/*
 * Create a payment of "amount" for the invoice owner and attempt
 * to balance it with the given invoice.
 */
void
gncInvoiceApplyPayment (const GncInvoice *invoice, Transaction *txn,
                        Account *xfer_acc, gnc_numeric amount,
                        gnc_numeric exch, time64 date,
                        const char *memo, const char *num)
{
    GNCLot *payment_lot;
    GList *selected_lots = NULL;
    const GncOwner *owner;

    /* Verify our arguments */
    if (!invoice || !gncInvoiceIsPosted (invoice) || !xfer_acc) return;

    owner = gncOwnerGetEndOwner (gncInvoiceGetOwner (invoice));
    g_return_if_fail (owner->owner.undefined);

    /* Create a lot for this payment */
    payment_lot = gncOwnerCreatePaymentLotSecs (owner, &txn,
                                                invoice->posted_acc,
                                                xfer_acc, amount, exch,
                                                date, memo, num);

    /* Select the invoice as only payment candidate */
    selected_lots = g_list_prepend (selected_lots, invoice->posted_lot);

    /* And link the invoice lot and the payment lot together as well as possible. */
    if (payment_lot)
        selected_lots = g_list_prepend (selected_lots, payment_lot);
    gncOwnerAutoApplyPaymentsWithLots (owner, selected_lots);
}

gboolean gncInvoiceIsPosted (const GncInvoice *invoice)
{
    if (!invoice) return FALSE;
    return GNC_IS_TRANSACTION(gncInvoiceGetPostedTxn (invoice));
}

gboolean gncInvoiceIsPaid (const GncInvoice *invoice)
{
    if (!invoice) return FALSE;
    if (!invoice->posted_lot) return FALSE;
    return gnc_lot_is_closed (invoice->posted_lot);
}

/* ================================================================== */

void gncInvoiceBeginEdit (GncInvoice *invoice)
{
    qof_begin_edit (&invoice->inst);
}

static void gncInvoiceOnError (QofInstance *inst, QofBackendError errcode)
{
    PERR("Invoice QofBackend Failure: %d", errcode);
    gnc_engine_signal_commit_error (errcode);
}

static void gncInvoiceOnDone (QofInstance *invoice) { }

static void invoice_free (QofInstance *inst)
{
    GncInvoice *invoice = (GncInvoice *) inst;
    gncInvoiceFree (invoice);
}

void gncInvoiceCommitEdit (GncInvoice *invoice)
{
    if (!qof_commit_edit (QOF_INSTANCE(invoice))) return;
    qof_commit_edit_part2 (&invoice->inst, gncInvoiceOnError,
                           gncInvoiceOnDone, invoice_free);
}

int gncInvoiceCompare (const GncInvoice *a, const GncInvoice *b)
{
    int compare;

    if (a == b) return 0;
    if (!a) return -1;
    if (!b) return 1;

    compare = g_strcmp0 (a->id, b->id);
    if (compare) return compare;
    if (a->date_opened != b->date_opened) return a->date_opened - b->date_opened;
    if (a->date_posted != b->date_posted) return a->date_posted - b->date_posted;
    return qof_instance_guid_compare(a, b);
}

gboolean gncInvoiceEqual(const GncInvoice *a, const GncInvoice *b)
{
    if (a == NULL && b == NULL) return TRUE;
    if (a == NULL || b == NULL) return FALSE;

    g_return_val_if_fail (GNC_IS_INVOICE(a), FALSE);
    g_return_val_if_fail (GNC_IS_INVOICE(b), FALSE);

    if (g_strcmp0 (a->id, b->id) != 0)
    {
        PWARN("IDs differ: %s vs %s", a->id, b->id);
        return FALSE;
    }

    if (g_strcmp0 (a->notes, b->notes) != 0)
    {
        PWARN("Notes differ: %s vs %s", a->notes, b->notes);
        return FALSE;
    }

    if (g_strcmp0 (a->billing_id, b->billing_id) != 0)
    {
        PWARN("Billing IDs differ: %s vs %s", a->billing_id, b->billing_id);
        return FALSE;
    }

    if (g_strcmp0 (a->printname, b->printname) != 0)
    {
        PWARN("Printnames differ: %s vs %s", a->printname, b->printname);
        return FALSE;
    }

    if (a->active != b->active)
    {
        PWARN("Active flags differ");
        return FALSE;
    }

    if (!gncBillTermEqual (a->terms, b->terms))
    {
        PWARN("Billterms differ");
        return FALSE;
    }

    if (!gncJobEqual (a->job, b->job))
    {
        PWARN("Jobs differ");
        return FALSE;
    }

    if (!gnc_commodity_equal (a->currency, b->currency))
    {
        PWARN("Currencies differ");
        return FALSE;
    }

    if (!xaccAccountEqual (a->posted_acc, b->posted_acc, TRUE))
    {
        PWARN("Posted accounts differ");
        return FALSE;
    }

    if (!xaccTransEqual (a->posted_txn, b->posted_txn, TRUE, TRUE, TRUE, FALSE))
    {
        PWARN("Posted tx differ");
        return FALSE;
    }

#if 0
    if (!gncLotEqual (a->posted_lot, b->posted_lot))
    {
        PWARN("Posted lots differ");
        return FALSE;
    }
#endif

    /* FIXME: Need real checks */
#if 0
    GList       *entries;
    GList       *prices;
    GncOwner    owner;
    GncOwner    billto;
    time64      date_opened;
    time64      date_posted;

    gnc_numeric to_charge_amount;
#endif

    return TRUE;
}

/* ============================================================= */
/* Package-Private functions */

static const char * _gncInvoicePrintable (gpointer obj)
{
    GncInvoice *invoice = obj;

    g_return_val_if_fail (invoice, NULL);

    if (qof_instance_get_dirty_flag (invoice) || invoice->printname == NULL)
    {
        if (invoice->printname) g_free (invoice->printname);

        invoice->printname =
            g_strdup_printf ("%s%s", invoice->id,
                             gncInvoiceIsPosted (invoice) ? _(" (posted)") : "");
    }

    return invoice->printname;
}

static void
destroy_invoice_on_book_close (QofInstance *ent, gpointer data)
{
    GncInvoice* invoice = GNC_INVOICE(ent);

    gncInvoiceBeginEdit (invoice);
    gncInvoiceDestroy (invoice);
}

static void
gnc_invoice_book_end (QofBook* book)
{
    QofCollection *col;

    col = qof_book_get_collection (book, GNC_ID_INVOICE);
    qof_collection_foreach (col, destroy_invoice_on_book_close, NULL);
}

static QofObject gncInvoiceDesc =
{
    DI(.interface_version = ) QOF_OBJECT_VERSION,
    DI(.e_type            = ) _GNC_MOD_NAME,
    DI(.type_label        = ) "Invoice",
    DI(.create            = ) (gpointer)gncInvoiceCreate,
    DI(.book_begin        = ) NULL,
    DI(.book_end          = ) gnc_invoice_book_end,
    DI(.is_dirty          = ) qof_collection_is_dirty,
    DI(.mark_clean        = ) qof_collection_mark_clean,
    DI(.foreach           = ) qof_collection_foreach,
    DI(.printable         = ) _gncInvoicePrintable,
    DI(.version_cmp       = ) (int (*)(gpointer, gpointer)) qof_instance_version_cmp,
};

static void
reg_lot (void)
{
    static QofParam params[] =
    {
        {
            INVOICE_FROM_LOT, _GNC_MOD_NAME,
            (QofAccessFunc)gncInvoiceGetInvoiceFromLot, NULL
        },
        { NULL },
    };

    qof_class_register (GNC_ID_LOT, NULL, params);
}

static void
reg_txn (void)
{
    static QofParam params[] =
    {
        {
            INVOICE_FROM_TXN, _GNC_MOD_NAME,
            (QofAccessFunc)gncInvoiceGetInvoiceFromTxn, NULL
        },
        { NULL },
    };

    qof_class_register (GNC_ID_TRANS, NULL, params);
}

gboolean gncInvoiceRegister (void)
{
    static QofParam params[] =
    {
        { INVOICE_ID,        QOF_TYPE_STRING,  (QofAccessFunc)gncInvoiceGetID,     (QofSetterFunc)gncInvoiceSetID },
        { INVOICE_OWNER,     GNC_ID_OWNER,     (QofAccessFunc)gncInvoiceGetOwner, NULL },
        { INVOICE_OPENED,    QOF_TYPE_DATE,    (QofAccessFunc)gncInvoiceGetDateOpened, (QofSetterFunc)gncInvoiceSetDateOpened },
        { INVOICE_DUE,       QOF_TYPE_DATE,    (QofAccessFunc)gncInvoiceGetDateDue, NULL },
        { INVOICE_POSTED,    QOF_TYPE_DATE,    (QofAccessFunc)gncInvoiceGetDatePosted, (QofSetterFunc)gncInvoiceSetDatePosted },
        { INVOICE_IS_POSTED, QOF_TYPE_BOOLEAN, (QofAccessFunc)gncInvoiceIsPosted, NULL },
        { INVOICE_IS_PAID,   QOF_TYPE_BOOLEAN, (QofAccessFunc)gncInvoiceIsPaid,    NULL },
        { INVOICE_BILLINGID, QOF_TYPE_STRING,  (QofAccessFunc)gncInvoiceGetBillingID, (QofSetterFunc)gncInvoiceSetBillingID },
        { INVOICE_NOTES,     QOF_TYPE_STRING,  (QofAccessFunc)gncInvoiceGetNotes,   (QofSetterFunc)gncInvoiceSetNotes },
        { INVOICE_DOCLINK, QOF_TYPE_STRING, (QofAccessFunc)gncInvoiceGetDocLink, (QofSetterFunc)gncInvoiceSetDocLink },
        { INVOICE_ACC,       GNC_ID_ACCOUNT,   (QofAccessFunc)gncInvoiceGetPostedAcc, (QofSetterFunc)gncInvoiceSetPostedAcc },
        { INVOICE_POST_TXN,  GNC_ID_TRANS,     (QofAccessFunc)gncInvoiceGetPostedTxn, (QofSetterFunc)gncInvoiceSetPostedTxn },
        { INVOICE_POST_LOT,  GNC_ID_LOT,       (QofAccessFunc)gncInvoiceGetPostedLot, NULL/*(QofSetterFunc)gncInvoiceSetPostedLot*/ },
        { INVOICE_TYPE,      QOF_TYPE_INT32,   (QofAccessFunc)gncInvoiceGetType,    NULL },
        { INVOICE_TYPE_STRING, QOF_TYPE_STRING, (QofAccessFunc)gncInvoiceGetTypeString,    NULL },
        { INVOICE_TERMS,     GNC_ID_BILLTERM,  (QofAccessFunc)gncInvoiceGetTerms,   (QofSetterFunc)gncInvoiceSetTerms },
        { INVOICE_BILLTO,    GNC_ID_OWNER,     (QofAccessFunc)gncInvoiceGetBillTo, NULL  },
        { INVOICE_ENTRIES,   QOF_TYPE_COLLECT, (QofAccessFunc)qofInvoiceGetEntries, (QofSetterFunc)qofInvoiceSetEntries },
        { INVOICE_JOB,       GNC_ID_JOB,       (QofAccessFunc)qofInvoiceGetJob,     (QofSetterFunc)qofInvoiceSetJob },
        { QOF_PARAM_ACTIVE,  QOF_TYPE_BOOLEAN, (QofAccessFunc)gncInvoiceGetActive, (QofSetterFunc)gncInvoiceSetActive },
        { INVOICE_IS_CN,     QOF_TYPE_BOOLEAN, (QofAccessFunc)gncInvoiceGetIsCreditNote, (QofSetterFunc)gncInvoiceSetIsCreditNote },
        { QOF_PARAM_BOOK,    QOF_ID_BOOK,      (QofAccessFunc)qof_instance_get_book, NULL },
        { QOF_PARAM_GUID,    QOF_TYPE_GUID,    (QofAccessFunc)qof_instance_get_guid, NULL },
        { NULL },
    };

    qof_class_register (_GNC_MOD_NAME, (QofSortFunc)gncInvoiceCompare, params);
    reg_lot ();
    reg_txn ();

    /* Make the compiler happy... */
    if (0)
    {
        qofInvoiceSetEntries (NULL, NULL);
        qofInvoiceGetEntries (NULL);
        qofInvoiceSetOwner (NULL, NULL);
        qofInvoiceGetOwner (NULL);
        qofInvoiceSetBillTo (NULL, NULL);
        qofInvoiceGetBillTo (NULL);
    }
    return qof_object_register (&gncInvoiceDesc);
}

gchar *gncInvoiceNextID (QofBook *book, const GncOwner *owner)
{
    gchar *nextID;
    switch (gncOwnerGetType (gncOwnerGetEndOwner (owner)))
    {
    case GNC_OWNER_CUSTOMER:
        nextID = qof_book_increment_and_format_counter (book, "gncInvoice");
        break;
    case GNC_OWNER_VENDOR:
        nextID = qof_book_increment_and_format_counter (book, "gncBill");
        break;
    case GNC_OWNER_EMPLOYEE:
        nextID = qof_book_increment_and_format_counter (book, "gncExpVoucher");
        break;
    default:
        nextID = qof_book_increment_and_format_counter (book, _GNC_MOD_NAME);
        break;
    }
    return nextID;
}