gncVendor.c

/********************************************************************\
 * gncVendor.c -- the Core Vendor Interface                         *
 *                                                                  *
 * 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 Derek Atkins
 * Copyright (C) 2003 <linas@linas.org>
 * Author: Derek Atkins <warlord@MIT.EDU>
 */

#include <config.h>

#include <glib.h>
#include <string.h>
#include <qofinstance-p.h>

#include "gnc-commodity.h"
#include "gncAddressP.h"
#include "gncBillTermP.h"
#include "gncInvoice.h"
#include "gncJobP.h"
#include "gncTaxTableP.h"
#include "gncVendor.h"
#include "gncVendorP.h"

static gint vend_qof_event_handler_id = 0;
static void vend_handle_qof_events (QofInstance *entity, QofEventId event_type,
                                    gpointer user_data, gpointer event_data);
static void qofVendorSetAddr (GncVendor *vendor, QofInstance *addr_ent);
static const char* qofVendorGetTaxIncluded(const GncVendor *vendor);
static void qofVendorSetTaxIncluded(GncVendor *vendor, const char* type_string);

struct _gncVendor
{
    QofInstance     inst;

    const char *    id;
    const char *    name;
    const char *    notes;
    GncBillTerm *   terms;
    GncAddress *    addr;
    gnc_commodity * currency;
    GncTaxTable*    taxtable;
    gboolean        taxtable_override;
    GncTaxIncluded  taxincluded;
    gboolean        active;
    GList *         jobs;
    gnc_numeric *   balance; /* cached vendor balance, will not be stored */
};

struct _gncVendorClass
{
    QofInstanceClass parent_class;
};

static QofLogModule log_module = GNC_MOD_BUSINESS;

#define _GNC_MOD_NAME        GNC_ID_VENDOR

/* ============================================================ */
/* Misc inline funcs */

static inline void mark_vendor (GncVendor *vendor);
void mark_vendor (GncVendor *vendor)
{
    qof_instance_set_dirty(&vendor->inst);
    qof_event_gen (&vendor->inst, QOF_EVENT_MODIFY, NULL);
}

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

enum
{
    PROP_0,
    PROP_NAME,          /* Table */
    PROP_ID,            /* Table */
    PROP_NOTES,         /* Table */
    PROP_CURRENCY,      /* Table */
    PROP_ACTIVE,        /* Table */
    PROP_TAXTABLE_OVERRIDE, /* Table */
    PROP_BILLTERMS,     /* Table */
    PROP_TAXTABLE,      /* Table */
    PROP_ADDRESS,       /* Table, 8 fields */
    PROP_TAX_INCLUDED,      /* Table */
    PROP_TAX_INCLUDED_STR,  /* Alternate setter for PROP_TAX_INCLUDED */
    PROP_PDF_DIRNAME,       /* KVP */
    PROP_LAST_POSTED,       /* KVP */
    PROP_PAYMENT_LAST_ACCT, /* KVP */
};

/* GObject Initialization */
G_DEFINE_TYPE(GncVendor, gnc_vendor, QOF_TYPE_INSTANCE)

static void
gnc_vendor_init(GncVendor* vendor)
{
}

static void
gnc_vendor_dispose(GObject *vendorp)
{
    G_OBJECT_CLASS(gnc_vendor_parent_class)->dispose(vendorp);
}

static void
gnc_vendor_finalize(GObject* vendorp)
{
    G_OBJECT_CLASS(gnc_vendor_parent_class)->finalize(vendorp);
}

/* Note that g_value_set_object() refs the object, as does
 * g_object_get(). But g_object_get() only unrefs once when it disgorges
 * the object, leaving an unbalanced ref, which leaks. So instead of
 * using g_value_set_object(), use g_value_take_object() which doesn't
 * ref the object when used in get_property().
 */
static void
gnc_vendor_get_property (GObject         *object,
                         guint            prop_id,
                         GValue          *value,
                         GParamSpec      *pspec)
{
    GncVendor *vendor;

    g_return_if_fail(GNC_IS_VENDOR(object));

    vendor = GNC_VENDOR(object);
    switch (prop_id)
    {
    case PROP_NAME:
        g_value_set_string(value, vendor->name);
        break;
    case PROP_ID:
        g_value_set_string(value, vendor->id);
        break;
    case PROP_NOTES:
        g_value_set_string(value, vendor->notes);
        break;
    case PROP_CURRENCY:
        g_value_take_object(value, vendor->currency);
        break;
    case PROP_ACTIVE:
        g_value_set_boolean(value, vendor->active);
        break;
    case PROP_TAXTABLE_OVERRIDE:
        g_value_set_boolean(value, vendor->taxtable_override);
        break;
    case PROP_BILLTERMS:
        g_value_take_object(value, vendor->terms);
        break;
    case PROP_TAXTABLE:
        g_value_take_object(value, vendor->taxtable);
        break;
    case PROP_ADDRESS:
        g_value_take_object(value, vendor->addr);
        break;
    case PROP_TAX_INCLUDED:
        g_value_set_int(value, vendor->taxincluded);
        break;
    case PROP_TAX_INCLUDED_STR:
        g_value_set_string(value, qofVendorGetTaxIncluded(vendor));
        break;
    case PROP_PDF_DIRNAME:
        qof_instance_get_kvp (QOF_INSTANCE (vendor), value, 1, OWNER_EXPORT_PDF_DIRNAME);
        break;
    case PROP_LAST_POSTED:
        qof_instance_get_kvp (QOF_INSTANCE (vendor), value, 1, LAST_POSTED_TO_ACCT);
        break;
    case PROP_PAYMENT_LAST_ACCT:
        qof_instance_get_kvp (QOF_INSTANCE (vendor), value, 2, GNC_PAYMENT, GNC_LAST_ACCOUNT);
        break;
    default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
        break;
    }
}

static void
gnc_vendor_set_property (GObject         *object,
                         guint            prop_id,
                         const GValue          *value,
                         GParamSpec      *pspec)
{
    GncVendor *vendor;

    g_return_if_fail(GNC_IS_VENDOR(object));

    vendor = GNC_VENDOR(object);
    g_assert (qof_instance_get_editlevel(vendor));

    switch (prop_id)
    {
    case PROP_NAME:
        gncVendorSetName(vendor, g_value_get_string(value));
        break;
    case PROP_ID:
        gncVendorSetID(vendor, g_value_get_string(value));
        break;
    case PROP_NOTES:
        gncVendorSetNotes(vendor, g_value_get_string(value));
        break;
    case PROP_CURRENCY:
        gncVendorSetCurrency(vendor, g_value_get_object(value));
        break;
    case PROP_ACTIVE:
        gncVendorSetActive(vendor, g_value_get_boolean(value));
        break;
    case PROP_TAXTABLE_OVERRIDE:
        gncVendorSetTaxTableOverride(vendor, g_value_get_boolean(value));
        break;
    case PROP_BILLTERMS:
        gncVendorSetTerms(vendor, g_value_get_object(value));
        break;
    case PROP_TAXTABLE:
        gncVendorSetTaxTable(vendor, g_value_get_object(value));
        break;
    case PROP_ADDRESS:
        qofVendorSetAddr(vendor, g_value_get_object(value));
        break;
    case PROP_TAX_INCLUDED:
        gncVendorSetTaxIncluded(vendor, (GncTaxIncluded)g_value_get_int(value));
        break;
    case PROP_TAX_INCLUDED_STR:
        qofVendorSetTaxIncluded(vendor, g_value_get_string(value));
        break;
    case PROP_PDF_DIRNAME:
        qof_instance_set_kvp (QOF_INSTANCE (vendor), value, 1, OWNER_EXPORT_PDF_DIRNAME);
        break;
    case PROP_LAST_POSTED:
        qof_instance_set_kvp (QOF_INSTANCE (vendor), value, 1, LAST_POSTED_TO_ACCT);
        break;
    case PROP_PAYMENT_LAST_ACCT:
        qof_instance_set_kvp (QOF_INSTANCE (vendor), value, 2, GNC_PAYMENT, GNC_LAST_ACCOUNT);
        break;
    default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
        break;
    }
}

static gboolean
impl_refers_to_object(const QofInstance* inst, const QofInstance* ref)
{
    GncVendor* v;

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

    v = GNC_VENDOR(inst);

    if (GNC_IS_BILLTERM(ref))
    {
        return (v->terms == GNC_BILLTERM(ref));
    }
    else if (GNC_IS_TAXTABLE(ref))
    {
        return (v->taxtable == GNC_TAXTABLE(ref));
    }

    return FALSE;
}

static GList*
impl_get_typed_referring_object_list(const QofInstance* inst, const QofInstance* ref)
{
    if (!GNC_IS_BILLTERM(ref) && !GNC_IS_TAXTABLE(ref))
    {
        return NULL;
    }

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

static void
gnc_vendor_class_init (GncVendorClass *klass)
{
    GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
    QofInstanceClass* qof_class = QOF_INSTANCE_CLASS(klass);

    gobject_class->dispose = gnc_vendor_dispose;
    gobject_class->finalize = gnc_vendor_finalize;
    gobject_class->set_property = gnc_vendor_set_property;
    gobject_class->get_property = gnc_vendor_get_property;

    qof_class->get_display_name = NULL;
    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_NAME,
     g_param_spec_string ("name",
                          "Vendor Name",
                          "The vendor name is an arbitrary string "
                          "assigned by the user to provide the vendor name.",
                          NULL,
                          G_PARAM_READWRITE));

    g_object_class_install_property
    (gobject_class,
     PROP_ID,
     g_param_spec_string ("id",
                          "Vendor ID",
                          "The vendor id is an arbitrary string "
                          "assigned by the user to identify the vendor.",
                          NULL,
                          G_PARAM_READWRITE));

    g_object_class_install_property
    (gobject_class,
     PROP_NOTES,
     g_param_spec_string ("notes",
                          "Vendor notes",
                          "The vendor notes is an arbitrary string "
                          "assigned by the user to add extra information about the vendor.",
                          NULL,
                          G_PARAM_READWRITE));

    g_object_class_install_property
    (gobject_class,
     PROP_CURRENCY,
     g_param_spec_object ("currency",
                          "Currency",
                          "The currency property denotes the currency used by this vendor.",
                          GNC_TYPE_COMMODITY,
                          G_PARAM_READWRITE));

    g_object_class_install_property
    (gobject_class,
     PROP_ACTIVE,
     g_param_spec_boolean ("active",
                           "Active",
                           "TRUE if the vendor is active.  FALSE if inactive.",
                           FALSE,
                           G_PARAM_READWRITE));

    g_object_class_install_property
    (gobject_class,
     PROP_TAXTABLE_OVERRIDE,
     g_param_spec_boolean ("tax-table-override",
                           "Tax table override",
                           "TRUE if the vendor has a specific tax table which overrides the default "
                           "tax table.  FALSE if the default table should be used.",
                           FALSE,
                           G_PARAM_READWRITE));

    g_object_class_install_property
    (gobject_class,
     PROP_BILLTERMS,
     g_param_spec_object ("terms",
                          "Terms",
                          "The billing terms used by this vendor.",
                          GNC_TYPE_BILLTERM,
                          G_PARAM_READWRITE));

    g_object_class_install_property
    (gobject_class,
     PROP_TAXTABLE,
     g_param_spec_object ("tax-table",
                          "Tax table",
                          "The tax table which applies to this vendor.",
                          GNC_TYPE_TAXTABLE,
                          G_PARAM_READWRITE));

    g_object_class_install_property
    (gobject_class,
     PROP_ADDRESS,
     g_param_spec_object ("address",
                          "Address",
                          "The address property contains the address information for this vendor.",
                          GNC_TYPE_ADDRESS,
                          G_PARAM_READWRITE));

    g_object_class_install_property
    (gobject_class,
     PROP_TAX_INCLUDED,
     g_param_spec_int  ("tax-included",
                        "Tax included",
                        "The tax-included property contains the information about tax calculation this vendor.",
                        GNC_TAXINCLUDED_YES,       /* min */
                        GNC_TAXINCLUDED_USEGLOBAL, /* max */
                        GNC_TAXINCLUDED_USEGLOBAL, /* default */
                        G_PARAM_READWRITE));

    g_object_class_install_property
    (gobject_class,
     PROP_TAX_INCLUDED_STR,
     g_param_spec_string("tax-included-string",
                         "Tax included string",
                         "The tax-included-string property contains a character version of tax-included.",
                         FALSE,
                         G_PARAM_READWRITE));
    g_object_class_install_property
    (gobject_class,
     PROP_PDF_DIRNAME,
     g_param_spec_string ("export-pdf-dir",
                          "Export PDF Directory Name",
                          "A subdirectory for exporting PDF reports which is "
              "appended to the target directory when writing them "
              "out. It is retrieved from preferences and stored on "
              "each 'Owner' object which prints items after "
              "printing.",
                          NULL,
                          G_PARAM_READWRITE));

    g_object_class_install_property(
       gobject_class,
       PROP_LAST_POSTED,
       g_param_spec_boxed("invoice-last-posted-account",
              "Invoice Last Posted Account",
              "The last account to which an invoice belonging to "
              "this owner was posted.",
              GNC_TYPE_GUID,
              G_PARAM_READWRITE));

    g_object_class_install_property(
       gobject_class,
       PROP_PAYMENT_LAST_ACCT,
       g_param_spec_boxed("payment-last-account",
              "Payment Last Account",
              "The last account to which an payment belonging to "
              "this owner was posted.",
              GNC_TYPE_GUID,
              G_PARAM_READWRITE));
}

/* Create/Destroy Functions */
GncVendor *gncVendorCreate (QofBook *book)
{
    GncVendor *vendor;

    if (!book) return NULL;

    vendor = g_object_new (GNC_TYPE_VENDOR, NULL);
    qof_instance_init_data (&vendor->inst, _GNC_MOD_NAME, book);

    vendor->id = CACHE_INSERT ("");
    vendor->name = CACHE_INSERT ("");
    vendor->notes = CACHE_INSERT ("");
    vendor->addr = gncAddressCreate (book, &vendor->inst);
    vendor->taxincluded = GNC_TAXINCLUDED_USEGLOBAL;
    vendor->active = TRUE;
    vendor->jobs = NULL;
    vendor->balance = NULL;

    if (vend_qof_event_handler_id == 0)
        vend_qof_event_handler_id = qof_event_register_handler (vend_handle_qof_events, NULL);

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

    return vendor;
}

void gncVendorDestroy (GncVendor *vendor)
{
    if (!vendor) return;
    qof_instance_set_destroying(vendor, TRUE);
    gncVendorCommitEdit (vendor);
}

static void gncVendorFree (GncVendor *vendor)
{
    if (!vendor) return;

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

    CACHE_REMOVE (vendor->id);
    CACHE_REMOVE (vendor->name);
    CACHE_REMOVE (vendor->notes);
    gncAddressBeginEdit (vendor->addr);
    gncAddressDestroy (vendor->addr);

    gncJobFreeList (vendor->jobs);
    g_list_free (vendor->jobs);
    g_free (vendor->balance);

    if (!qof_book_shutting_down (qof_instance_get_book (QOF_INSTANCE(vendor))))
    {
        if (vendor->terms)
            gncBillTermDecRef (vendor->terms);
        if (vendor->taxtable)
            gncTaxTableDecRef (vendor->taxtable);
    }

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

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

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

void gncVendorSetID (GncVendor *vendor, const char *id)
{
    if (!vendor) return;
    if (!id) return;
    SET_STR(vendor, vendor->id, id);
    mark_vendor (vendor);
    gncVendorCommitEdit (vendor);
}

void gncVendorSetName (GncVendor *vendor, const char *name)
{
    if (!vendor) return;
    if (!name) return;
    SET_STR(vendor, vendor->name, name);
    mark_vendor (vendor);
    gncVendorCommitEdit (vendor);
}

void gncVendorSetNotes (GncVendor *vendor, const char *notes)
{
    if (!vendor) return;
    if (!notes) return;
    SET_STR(vendor, vendor->notes, notes);
    mark_vendor (vendor);
    gncVendorCommitEdit (vendor);
}

void gncVendorSetTerms (GncVendor *vendor, GncBillTerm *terms)
{
    if (!vendor) return;
    if (vendor->terms == terms) return;

    gncVendorBeginEdit (vendor);
    if (vendor->terms)
        gncBillTermDecRef (vendor->terms);
    vendor->terms = terms;
    if (vendor->terms)
        gncBillTermIncRef (vendor->terms);
    mark_vendor (vendor);
    gncVendorCommitEdit (vendor);
}

void gncVendorSetTaxIncluded (GncVendor *vendor, GncTaxIncluded taxincl)
{
    if (!vendor) return;
    if (taxincl == vendor->taxincluded) return;
    gncVendorBeginEdit (vendor);
    vendor->taxincluded = taxincl;
    mark_vendor (vendor);
    gncVendorCommitEdit (vendor);
}

void gncVendorSetCurrency (GncVendor *vendor, gnc_commodity *currency)
{
    if (!vendor || !currency) return;
    if (vendor->currency &&
            gnc_commodity_equal (vendor->currency, currency))
        return;
    gncVendorBeginEdit (vendor);
    vendor->currency = currency;
    mark_vendor (vendor);
    gncVendorCommitEdit (vendor);
}

void gncVendorSetActive (GncVendor *vendor, gboolean active)
{
    if (!vendor) return;
    if (active == vendor->active) return;
    gncVendorBeginEdit (vendor);
    vendor->active = active;
    mark_vendor (vendor);
    gncVendorCommitEdit (vendor);
}

void gncVendorSetTaxTableOverride (GncVendor *vendor, gboolean override)
{
    if (!vendor) return;
    if (vendor->taxtable_override == override) return;
    gncVendorBeginEdit (vendor);
    vendor->taxtable_override = override;
    mark_vendor (vendor);
    gncVendorCommitEdit (vendor);
}

void gncVendorSetTaxTable (GncVendor *vendor, GncTaxTable *table)
{
    if (!vendor) return;
    if (vendor->taxtable == table) return;
    gncVendorBeginEdit (vendor);
    if (vendor->taxtable)
        gncTaxTableDecRef (vendor->taxtable);
    if (table)
        gncTaxTableIncRef (table);
    vendor->taxtable = table;
    mark_vendor (vendor);
    gncVendorCommitEdit (vendor);
}

static void
qofVendorSetAddr (GncVendor *vendor, QofInstance *addr_ent)
{
    GncAddress *addr;

    if (!vendor || !addr_ent)
    {
        return;
    }
    addr = (GncAddress*)addr_ent;
    if (addr == vendor->addr)
    {
        return;
    }
    if (vendor->addr != NULL)
    {
        gncAddressBeginEdit(vendor->addr);
        gncAddressDestroy(vendor->addr);
    }
    gncVendorBeginEdit(vendor);
    vendor->addr = addr;
    gncVendorCommitEdit(vendor);
}

static void
qofVendorSetTaxIncluded(GncVendor *vendor, const char* type_string)
{
    GncTaxIncluded inc;

    if (!gncTaxIncludedStringToType(type_string, &inc))
    {
        return;
    }
    gncVendorBeginEdit(vendor);
    vendor->taxincluded = inc;
    gncVendorCommitEdit(vendor);
}

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

const char * gncVendorGetID (const GncVendor *vendor)
{
    if (!vendor) return NULL;
    return vendor->id;
}

const char * gncVendorGetName (const GncVendor *vendor)
{
    if (!vendor) return NULL;
    return vendor->name;
}

GncAddress * gncVendorGetAddr (const GncVendor *vendor)
{
    if (!vendor) return NULL;
    return vendor->addr;
}

const char * gncVendorGetNotes (const GncVendor *vendor)
{
    if (!vendor) return NULL;
    return vendor->notes;
}

GncBillTerm * gncVendorGetTerms (const GncVendor *vendor)
{
    if (!vendor) return 0;
    return vendor->terms;
}

GncTaxIncluded gncVendorGetTaxIncluded (const GncVendor *vendor)
{
    if (!vendor) return GNC_TAXINCLUDED_USEGLOBAL;
    return vendor->taxincluded;
}

gnc_commodity * gncVendorGetCurrency (const GncVendor *vendor)
{
    if (!vendor) return NULL;
    return vendor->currency;
}

gboolean gncVendorGetActive (const GncVendor *vendor)
{
    if (!vendor) return FALSE;
    return vendor->active;
}

gboolean gncVendorGetTaxTableOverride (const GncVendor *vendor)
{
    if (!vendor) return FALSE;
    return vendor->taxtable_override;
}

GncTaxTable* gncVendorGetTaxTable (const GncVendor *vendor)
{
    if (!vendor) return NULL;
    return vendor->taxtable;
}

static const char*
qofVendorGetTaxIncluded(const GncVendor *vendor)
{
    return gncTaxIncludedTypeToString(vendor->taxincluded);
}

/* Note that JobList changes do not affect the "dirtiness" of the vendor */
void gncVendorAddJob (GncVendor *vendor, GncJob *job)
{
    if (!vendor) return;
    if (!job) return;

    if (g_list_index(vendor->jobs, job) == -1)
        vendor->jobs = g_list_insert_sorted (vendor->jobs, job,
                                             (GCompareFunc)gncJobCompare);

    qof_event_gen (&vendor->inst, QOF_EVENT_MODIFY, NULL);
}

void gncVendorRemoveJob (GncVendor *vendor, GncJob *job)
{
    GList *node;

    if (!vendor) return;
    if (!job) return;

    node = g_list_find (vendor->jobs, job);
    if (!node)
    {
        /*    PERR ("split not in account"); */
    }
    else
    {
        vendor->jobs = g_list_remove_link (vendor->jobs, node);
        g_list_free_1 (node);
    }

    qof_event_gen (&vendor->inst, QOF_EVENT_MODIFY, NULL);
}

void gncVendorBeginEdit (GncVendor *vendor)
{
    qof_begin_edit(&vendor->inst);
}

static void gncVendorOnError (QofInstance *vendor, QofBackendError errcode)
{
    PERR("Vendor QofBackend Failure: %d", errcode);
    gnc_engine_signal_commit_error( errcode );
}

static void gncVendorOnDone (QofInstance *inst)
{
    GncVendor *vendor = (GncVendor *) inst;
    gncAddressClearDirty (vendor->addr);
}

static void vendor_free (QofInstance *inst)
{
    GncVendor *vendor = (GncVendor *) inst;
    gncVendorFree (vendor);
}

void gncVendorCommitEdit (GncVendor *vendor)
{
    if (!qof_commit_edit (QOF_INSTANCE(vendor))) return;
    qof_commit_edit_part2 (&vendor->inst, gncVendorOnError,
                           gncVendorOnDone, vendor_free);
}

/* ============================================================== */
/* Other functions */

int gncVendorCompare (const GncVendor *a, const GncVendor *b)
{
    if (!a && !b) return 0;
    if (!a && b) return 1;
    if (a && !b) return -1;

    return(strcmp(a->name, b->name));
}

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

    g_return_val_if_fail(GNC_IS_VENDOR(a), FALSE);
    g_return_val_if_fail(GNC_IS_VENDOR(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->name, b->name) != 0)
    {
        PWARN("Names differ: %s vs %s", a->name, b->name);
        return FALSE;
    }

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

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

    if (!gncAddressEqual(a->addr, b->addr))
    {
        PWARN("Addresses differ");
        return FALSE;
    }

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

    if (!gncTaxTableEqual(a->taxtable, b->taxtable))
    {
        PWARN("Tax tables differ");
        return FALSE;
    }

    if (a->taxtable_override != b->taxtable_override)
    {
        PWARN("Tax table override flags differ");
        return FALSE;
    }

    if (a->taxincluded != b->taxincluded)
    {
        PWARN("Tax included flags differ");
        return FALSE;
    }

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

//    GList *         jobs;
    return TRUE;
}

gboolean
gncVendorIsDirty (const GncVendor *vendor)
{
    if (!vendor) return FALSE;
    return (qof_instance_get_dirty_flag(vendor)
            || gncAddressIsDirty (vendor->addr));
}

static void
vend_handle_qof_events (QofInstance *entity, QofEventId event_type,
                        gpointer user_data, gpointer event_data)
{
    /* Handle address change events */
    if ((GNC_IS_ADDRESS (entity) &&
        (event_type & QOF_EVENT_MODIFY) != 0))
    {
        if (GNC_IS_VENDOR (event_data))
        {
            GncVendor* vend = GNC_VENDOR (event_data);
            gncVendorBeginEdit (vend);
            mark_vendor (vend);
            gncVendorCommitEdit (vend);
        }
        return;
    }

    /* Handle lot change events */
    if (GNC_IS_LOT (entity))
    {
        GNCLot *lot = GNC_LOT (entity);
        GncOwner lot_owner;
        const GncOwner *end_owner = NULL;
        GncInvoice *invoice = gncInvoiceGetInvoiceFromLot (lot);

        /* Determine the owner associated with the lot */
        if (invoice)
            /* Invoice lots */
            end_owner = gncOwnerGetEndOwner (gncInvoiceGetOwner (invoice));
        else if (gncOwnerGetOwnerFromLot (lot, &lot_owner))
            /* Pre-payment lots */
            end_owner = gncOwnerGetEndOwner (&lot_owner);

        if (gncOwnerGetType (end_owner) == GNC_OWNER_VENDOR)
        {
            /* Clear the cached balance */
            GncVendor* vend = gncOwnerGetVendor (end_owner);
            g_free (vend->balance);
            vend->balance = NULL;
        }
        return;
    }
}

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

static const char * _gncVendorPrintable (gpointer item)
{
    GncVendor *v = item;
    if (!item) return NULL;
    return v->name;
}

static void
destroy_vendor_on_book_close(QofInstance *ent, gpointer data)
{
    GncVendor* v = GNC_VENDOR(ent);

    gncVendorBeginEdit(v);
    gncVendorDestroy(v);
}

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

    col = qof_book_get_collection(book, GNC_ID_VENDOR);
    qof_collection_foreach(col, destroy_vendor_on_book_close, NULL);
}

static QofObject gncVendorDesc =
{
    DI(.interface_version = ) QOF_OBJECT_VERSION,
    DI(.e_type            = ) _GNC_MOD_NAME,
    DI(.type_label        = ) "Vendor",
    DI(.create            = ) (gpointer)gncVendorCreate,
    DI(.book_begin        = ) NULL,
    DI(.book_end          = ) gnc_vendor_book_end,
    DI(.is_dirty          = ) qof_collection_is_dirty,
    DI(.mark_clean        = ) qof_collection_mark_clean,
    DI(.foreach           = ) qof_collection_foreach,
    DI(.printable         = ) _gncVendorPrintable,
    DI(.version_cmp       = ) (int (*)(gpointer, gpointer)) qof_instance_version_cmp,
};

gboolean gncVendorRegister (void)
{
    static QofParam params[] =
    {
        { VENDOR_ID, QOF_TYPE_STRING, (QofAccessFunc)gncVendorGetID, (QofSetterFunc)gncVendorSetID },
        { VENDOR_NAME, QOF_TYPE_STRING, (QofAccessFunc)gncVendorGetName, (QofSetterFunc)gncVendorSetName },
        { VENDOR_ADDR,    GNC_ID_ADDRESS, (QofAccessFunc)gncVendorGetAddr, (QofSetterFunc)qofVendorSetAddr },
        { VENDOR_NOTES,   QOF_TYPE_STRING, (QofAccessFunc)gncVendorGetNotes, (QofSetterFunc)gncVendorSetNotes },
        { VENDOR_TERMS,   GNC_ID_BILLTERM, (QofAccessFunc)gncVendorGetTerms, (QofSetterFunc)gncVendorSetTerms },
        {
            VENDOR_TAX_OVERRIDE, QOF_TYPE_BOOLEAN, (QofAccessFunc)gncVendorGetTaxTableOverride,
            (QofSetterFunc)gncVendorSetTaxTableOverride
        },
        {
            VENDOR_TAX_TABLE, GNC_ID_TAXTABLE, (QofAccessFunc)gncVendorGetTaxTable,
            (QofSetterFunc)gncVendorSetTaxTable
        },
        {
            VENDOR_TAX_INC, QOF_TYPE_STRING, (QofAccessFunc)qofVendorGetTaxIncluded,
            (QofSetterFunc)qofVendorSetTaxIncluded
        },
        { QOF_PARAM_BOOK, QOF_ID_BOOK, (QofAccessFunc)qof_instance_get_book, NULL },
        { QOF_PARAM_GUID, QOF_TYPE_GUID, (QofAccessFunc)qof_instance_get_guid, NULL },
        { QOF_PARAM_ACTIVE, QOF_TYPE_BOOLEAN, (QofAccessFunc)gncVendorGetActive, NULL },
        { NULL },
    };

    qof_class_register (_GNC_MOD_NAME, (QofSortFunc)gncVendorCompare, params);

    return qof_object_register (&gncVendorDesc);
}

gchar *gncVendorNextID (QofBook *book)
{
    return qof_book_increment_and_format_counter (book, _GNC_MOD_NAME);
}

const gnc_numeric*
gncVendorGetCachedBalance (GncVendor *vend)
{
    return vend->balance;
}

void gncVendorSetCachedBalance (GncVendor *vend, const gnc_numeric *new_bal)
{
    if (!new_bal)
    {
        if (vend->balance)
        {
            g_free (vend->balance);
            vend->balance = NULL;
        }
        return;
    }

    if (!vend->balance)
        vend->balance = g_new0 (gnc_numeric, 1);

    *vend->balance = *new_bal;
}