path: root/e-util/e-contact-store.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */

/* e-contact-store.c - Contacts store with GtkTreeModel interface.
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU Lesser General Public
 * License as published by the Free Software Foundation.
 *
 * 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * Authors: Hans Petter Jansson <hpj@novell.com>
 */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <string.h>
#include <glib/gi18n-lib.h>

#include "e-contact-store.h"

#define ITER_IS_VALID(contact_store, iter) \
    ((iter)->stamp == (contact_store)->priv->stamp)
#define ITER_GET(iter) \
    GPOINTER_TO_INT (iter->user_data)
#define ITER_SET(contact_store, iter, index) \
    G_STMT_START { \
    (iter)->stamp = (contact_store)->priv->stamp; \
    (iter)->user_data = GINT_TO_POINTER (index); \
    } G_STMT_END

#define E_CONTACT_STORE_GET_PRIVATE(obj) \
    (G_TYPE_INSTANCE_GET_PRIVATE \
    ((obj), E_TYPE_CONTACT_STORE, EContactStorePrivate))

struct _EContactStorePrivate {
    gint stamp;
    EBookQuery *query;
    GArray *contact_sources;
};

/* Signals */

enum {
    START_CLIENT_VIEW,
    STOP_CLIENT_VIEW,
    LAST_SIGNAL
};

static guint signals[LAST_SIGNAL] = { 0 };

static void e_contact_store_tree_model_init (GtkTreeModelIface *iface);

G_DEFINE_TYPE_WITH_CODE (
    EContactStore, e_contact_store, G_TYPE_OBJECT,
    G_IMPLEMENT_INTERFACE (GTK_TYPE_TREE_MODEL, e_contact_store_tree_model_init))

static GtkTreeModelFlags e_contact_store_get_flags       (GtkTreeModel       *tree_model);
static gint         e_contact_store_get_n_columns   (GtkTreeModel       *tree_model);
static GType        e_contact_store_get_column_type (GtkTreeModel       *tree_model,
                             gint                index);
static gboolean     e_contact_store_get_iter        (GtkTreeModel       *tree_model,
                             GtkTreeIter        *iter,
                             GtkTreePath        *path);
static GtkTreePath *e_contact_store_get_path        (GtkTreeModel       *tree_model,
                             GtkTreeIter        *iter);
static void         e_contact_store_get_value       (GtkTreeModel       *tree_model,
                             GtkTreeIter        *iter,
                             gint                column,
                             GValue             *value);
static gboolean     e_contact_store_iter_next       (GtkTreeModel       *tree_model,
                             GtkTreeIter        *iter);
static gboolean     e_contact_store_iter_children   (GtkTreeModel       *tree_model,
                             GtkTreeIter        *iter,
                             GtkTreeIter        *parent);
static gboolean     e_contact_store_iter_has_child  (GtkTreeModel       *tree_model,
                             GtkTreeIter        *iter);
static gint         e_contact_store_iter_n_children (GtkTreeModel       *tree_model,
                             GtkTreeIter        *iter);
static gboolean     e_contact_store_iter_nth_child  (GtkTreeModel       *tree_model,
                             GtkTreeIter        *iter,
                             GtkTreeIter        *parent,
                             gint                n);
static gboolean     e_contact_store_iter_parent     (GtkTreeModel       *tree_model,
                             GtkTreeIter        *iter,
                             GtkTreeIter        *child);

typedef struct
{
    EBookClient *book_client;

    EBookClientView *client_view;
    GPtrArray *contacts;

    EBookClientView *client_view_pending;
    GPtrArray *contacts_pending;
}
ContactSource;

static void free_contact_ptrarray (GPtrArray *contacts);
static void clear_contact_source  (EContactStore *contact_store, ContactSource *source);
static void stop_view             (EContactStore *contact_store, EBookClientView *view);

static void
contact_store_dispose (GObject *object)
{
    EContactStorePrivate *priv;
    gint ii;

    priv = E_CONTACT_STORE_GET_PRIVATE (object);

    /* Free sources and cached contacts */
    for (ii = 0; ii < priv->contact_sources->len; ii++) {
        ContactSource *source;

        /* clear from back, because clear_contact_source can later access freed memory */
        source = &g_array_index (
            priv->contact_sources, ContactSource, priv->contact_sources->len - ii - 1);

        clear_contact_source (E_CONTACT_STORE (object), source);
        free_contact_ptrarray (source->contacts);
        g_object_unref (source->book_client);
    }
    g_array_set_size (priv->contact_sources, 0);

    if (priv->query != NULL) {
        e_book_query_unref (priv->query);
        priv->query = NULL;
    }

    /* Chain up to parent's dispose() method. */
    G_OBJECT_CLASS (e_contact_store_parent_class)->dispose (object);
}

static void
contact_store_finalize (GObject *object)
{
    EContactStorePrivate *priv;

    priv = E_CONTACT_STORE_GET_PRIVATE (object);

    g_array_free (priv->contact_sources, TRUE);

    /* Chain up to parent's finalize() method. */
    G_OBJECT_CLASS (e_contact_store_parent_class)->finalize (object);
}

static void
e_contact_store_class_init (EContactStoreClass *class)
{
    GObjectClass *object_class;

    g_type_class_add_private (class, sizeof (EContactStorePrivate));

    object_class = G_OBJECT_CLASS (class);
    object_class->dispose = contact_store_dispose;
    object_class->finalize = contact_store_finalize;

    signals[START_CLIENT_VIEW] = g_signal_new (
        "start-client-view",
        G_OBJECT_CLASS_TYPE (object_class),
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (EContactStoreClass, start_client_view),
        NULL, NULL,
        g_cclosure_marshal_VOID__OBJECT,
        G_TYPE_NONE, 1,
        E_TYPE_BOOK_CLIENT_VIEW);

    signals[STOP_CLIENT_VIEW] = g_signal_new (
        "stop-client-view",
        G_OBJECT_CLASS_TYPE (object_class),
        G_SIGNAL_RUN_LAST,
        G_STRUCT_OFFSET (EContactStoreClass, stop_client_view),
        NULL, NULL,
        g_cclosure_marshal_VOID__OBJECT,
        G_TYPE_NONE, 1,
        E_TYPE_BOOK_CLIENT_VIEW);
}

static void
e_contact_store_tree_model_init (GtkTreeModelIface *iface)
{
    iface->get_flags       = e_contact_store_get_flags;
    iface->get_n_columns   = e_contact_store_get_n_columns;
    iface->get_column_type = e_contact_store_get_column_type;
    iface->get_iter        = e_contact_store_get_iter;
    iface->get_path        = e_contact_store_get_path;
    iface->get_value       = e_contact_store_get_value;
    iface->iter_next       = e_contact_store_iter_next;
    iface->iter_children   = e_contact_store_iter_children;
    iface->iter_has_child  = e_contact_store_iter_has_child;
    iface->iter_n_children = e_contact_store_iter_n_children;
    iface->iter_nth_child  = e_contact_store_iter_nth_child;
    iface->iter_parent     = e_contact_store_iter_parent;
}

static void
e_contact_store_init (EContactStore *contact_store)
{
    GArray *contact_sources;

    contact_sources = g_array_new (FALSE, FALSE, sizeof (ContactSource));

    contact_store->priv = E_CONTACT_STORE_GET_PRIVATE (contact_store);
    contact_store->priv->stamp = g_random_int ();
    contact_store->priv->contact_sources = contact_sources;
}

/**
 * e_contact_store_new:
 *
 * Creates a new #EContactStore.
 *
 * Returns: A new #EContactStore.
 **/
EContactStore *
e_contact_store_new (void)
{
    return g_object_new (E_TYPE_CONTACT_STORE, NULL);
}

/* ------------------ *
 * Row update helpers *
 * ------------------ */

static void
row_deleted (EContactStore *contact_store,
             gint n)
{
    GtkTreePath *path;

    path = gtk_tree_path_new ();
    gtk_tree_path_append_index (path, n);
    gtk_tree_model_row_deleted (GTK_TREE_MODEL (contact_store), path);
    gtk_tree_path_free (path);
}

static void
row_inserted (EContactStore *contact_store,
              gint n)
{
    GtkTreePath *path;
    GtkTreeIter  iter;

    path = gtk_tree_path_new ();
    gtk_tree_path_append_index (path, n);

    if (gtk_tree_model_get_iter (GTK_TREE_MODEL (contact_store), &iter, path))
        gtk_tree_model_row_inserted (GTK_TREE_MODEL (contact_store), path, &iter);

    gtk_tree_path_free (path);
}

static void
row_changed (EContactStore *contact_store,
             gint n)
{
    GtkTreePath *path;
    GtkTreeIter  iter;

    path = gtk_tree_path_new ();
    gtk_tree_path_append_index (path, n);

    if (gtk_tree_model_get_iter (GTK_TREE_MODEL (contact_store), &iter, path))
        gtk_tree_model_row_changed (GTK_TREE_MODEL (contact_store), path, &iter);

    gtk_tree_path_free (path);
}

/* ---------------------- *
 * Contact source helpers *
 * ---------------------- */

static gint
find_contact_source_by_client (EContactStore *contact_store,
                               EBookClient *book_client)
{
    GArray *array;
    gint i;

    array = contact_store->priv->contact_sources;

    for (i = 0; i < array->len; i++) {
        ContactSource *source;

        source = &g_array_index (array, ContactSource, i);
        if (source->book_client == book_client)
            return i;
    }

    return -1;
}

static gint
find_contact_source_by_view (EContactStore *contact_store,
                             EBookClientView *client_view)
{
    GArray *array;
    gint i;

    array = contact_store->priv->contact_sources;

    for (i = 0; i < array->len; i++) {
        ContactSource *source;

        source = &g_array_index (array, ContactSource, i);
        if (source->client_view == client_view ||
            source->client_view_pending == client_view)
            return i;
    }

    return -1;
}

static gint
find_contact_source_by_offset (EContactStore *contact_store,
                               gint offset)
{
    GArray *array;
    gint i;

    array = contact_store->priv->contact_sources;

    for (i = 0; i < array->len; i++) {
        ContactSource *source;

        source = &g_array_index (array, ContactSource, i);
        if (source->contacts->len > offset)
            return i;

        offset -= source->contacts->len;
    }

    return -1;
}

static gint
find_contact_source_by_pointer (EContactStore *contact_store,
                                ContactSource *source)
{
    GArray *array;
    gint i;

    array = contact_store->priv->contact_sources;

    i = ((gchar *) source - (gchar *) array->data) / sizeof (ContactSource);

    if (i < 0 || i >= array->len)
        return -1;

    return i;
}

static gint
get_contact_source_offset (EContactStore *contact_store,
                           gint contact_source_index)
{
    GArray *array;
    gint offset = 0;
    gint i;

    array = contact_store->priv->contact_sources;

    g_assert (contact_source_index < array->len);

    for (i = 0; i < contact_source_index; i++) {
        ContactSource *source;

        source = &g_array_index (array, ContactSource, i);
        offset += source->contacts->len;
    }

    return offset;
}

static gint
count_contacts (EContactStore *contact_store)
{
    GArray *array;
    gint count = 0;
    gint i;

    array = contact_store->priv->contact_sources;

    for (i = 0; i < array->len; i++) {
        ContactSource *source;

        source = &g_array_index (array, ContactSource, i);
        count += source->contacts->len;
    }

    return count;
}

static gint
find_contact_by_view_and_uid (EContactStore *contact_store,
                              EBookClientView *find_view,
                              const gchar *find_uid)
{
    GArray *array;
    ContactSource *source;
    GPtrArray *contacts;
    gint source_index;
    gint i;

    g_return_val_if_fail (find_uid != NULL, -1);

    source_index = find_contact_source_by_view (contact_store, find_view);
    if (source_index < 0)
        return -1;

    array = contact_store->priv->contact_sources;
    source = &g_array_index (array, ContactSource, source_index);

    if (find_view == source->client_view)
        contacts = source->contacts;          /* Current view */
    else
        contacts = source->contacts_pending;  /* Pending view */

    for (i = 0; i < contacts->len; i++) {
        EContact    *contact = g_ptr_array_index (contacts, i);
        const gchar *uid     = e_contact_get_const (contact, E_CONTACT_UID);

        if (uid && !strcmp (find_uid, uid))
            return i;
    }

    return -1;
}

static gint
find_contact_by_uid (EContactStore *contact_store,
                     const gchar *find_uid)
{
    GArray *array;
    gint i;

    array = contact_store->priv->contact_sources;

    for (i = 0; i < array->len; i++) {
        ContactSource *source = &g_array_index (array, ContactSource, i);
        gint           j;

        for (j = 0; j < source->contacts->len; j++) {
            EContact    *contact = g_ptr_array_index (source->contacts, j);
            const gchar *uid     = e_contact_get_const (contact, E_CONTACT_UID);

            if (!strcmp (find_uid, uid))
                return get_contact_source_offset (contact_store, i) + j;
        }
    }

    return -1;
}

static EBookClient *
get_book_at_row (EContactStore *contact_store,
                 gint row)
{
    GArray *array;
    ContactSource *source;
    gint source_index;

    source_index = find_contact_source_by_offset (contact_store, row);
    if (source_index < 0)
        return NULL;

    array = contact_store->priv->contact_sources;
    source = &g_array_index (array, ContactSource, source_index);

    return source->book_client;
}

static EContact *
get_contact_at_row (EContactStore *contact_store,
                    gint row)
{
    GArray *array;
    ContactSource *source;
    gint source_index;
    gint offset;

    source_index = find_contact_source_by_offset (contact_store, row);
    if (source_index < 0)
        return NULL;

    array = contact_store->priv->contact_sources;
    source = &g_array_index (array, ContactSource, source_index);
    offset = get_contact_source_offset (contact_store, source_index);
    row -= offset;

    g_assert (row < source->contacts->len);

    return g_ptr_array_index (source->contacts, row);
}

static gboolean
find_contact_source_details_by_view (EContactStore *contact_store,
                                     EBookClientView *client_view,
                                     ContactSource **contact_source,
                                     gint *offset)
{
    GArray *array;
    gint source_index;

    source_index = find_contact_source_by_view (contact_store, client_view);
    if (source_index < 0)
        return FALSE;

    array = contact_store->priv->contact_sources;
    *contact_source = &g_array_index (array, ContactSource, source_index);
    *offset = get_contact_source_offset (contact_store, source_index);

    return TRUE;
}

/* ------------------------- *
 * EBookView signal handlers *
 * ------------------------- */

static void
view_contacts_added (EContactStore *contact_store,
                     const GSList *contacts,
                     EBookClientView *client_view)
{
    ContactSource *source;
    gint           offset;
    const GSList  *l;

    if (!find_contact_source_details_by_view (contact_store, client_view, &source, &offset)) {
        g_warning ("EContactStore got 'contacts_added' signal from unknown EBookView!");
        return;
    }

    for (l = contacts; l; l = g_slist_next (l)) {
        EContact *contact = l->data;

        g_object_ref (contact);

        if (client_view == source->client_view) {
            /* Current view */
            g_ptr_array_add (source->contacts, contact);
            row_inserted (contact_store, offset + source->contacts->len - 1);
        } else {
            /* Pending view */
            g_ptr_array_add (source->contacts_pending, contact);
        }
    }
}

static void
view_contacts_removed (EContactStore *contact_store,
                       const GSList *uids,
                       EBookClientView *client_view)
{
    ContactSource *source;
    gint           offset;
    const GSList  *l;

    if (!find_contact_source_details_by_view (contact_store, client_view, &source, &offset)) {
        g_warning ("EContactStore got 'contacts_removed' signal from unknown EBookView!");
        return;
    }

    for (l = uids; l; l = g_slist_next (l)) {
        const gchar *uid = l->data;
        gint         n   = find_contact_by_view_and_uid (contact_store, client_view, uid);
        EContact    *contact;

        if (n < 0) {
            g_warning ("EContactStore got 'contacts_removed' on unknown contact!");
            continue;
        }

        if (client_view == source->client_view) {
            /* Current view */
            contact = g_ptr_array_index (source->contacts, n);
            g_object_unref (contact);
            g_ptr_array_remove_index (source->contacts, n);
            row_deleted (contact_store, offset + n);
        } else {
            /* Pending view */
            contact = g_ptr_array_index (source->contacts_pending, n);
            g_object_unref (contact);
            g_ptr_array_remove_index (source->contacts_pending, n);
        }
    }
}

static void
view_contacts_modified (EContactStore *contact_store,
                        const GSList *contacts,
                        EBookClientView *client_view)
{
    GPtrArray     *cached_contacts;
    ContactSource *source;
    gint           offset;
    const GSList  *l;

    if (!find_contact_source_details_by_view (contact_store, client_view, &source, &offset)) {
        g_warning ("EContactStore got 'contacts_changed' signal from unknown EBookView!");
        return;
    }

    if (client_view == source->client_view)
        cached_contacts = source->contacts;
    else
        cached_contacts = source->contacts_pending;

    for (l = contacts; l; l = g_slist_next (l)) {
        EContact    *cached_contact;
        EContact    *contact = l->data;
        const gchar *uid     = e_contact_get_const (contact, E_CONTACT_UID);
        gint         n       = find_contact_by_view_and_uid (contact_store, client_view, uid);

        if (n < 0) {
            g_warning ("EContactStore got change notification on unknown contact!");
            continue;
        }

        cached_contact = g_ptr_array_index (cached_contacts, n);

        /* Update cached contact */
        if (cached_contact != contact) {
            g_object_unref (cached_contact);
            cached_contacts->pdata[n] = g_object_ref (contact);
        }

        /* Emit changes for current view only */
        if (client_view == source->client_view)
            row_changed (contact_store, offset + n);
    }
}

static void
view_complete (EContactStore *contact_store,
               const GError *error,
               EBookClientView *client_view)
{
    ContactSource *source;
    gint           offset;
    gint           i;

    if (!find_contact_source_details_by_view (contact_store, client_view, &source, &offset)) {
        g_warning ("EContactStore got 'complete' signal from unknown EBookClientView!");
        return;
    }

    /* If current view finished, do nothing */
    if (client_view == source->client_view) {
        stop_view (contact_store, source->client_view);
        return;
    }

    g_assert (client_view == source->client_view_pending);

    /* However, if it was a pending view, calculate and emit the differences between that
     * and the current view, and move the pending view up to current.
     *
     * This is O(m * n), and can be sped up with a temporary hash table if needed. */

    /* Deletions */
    for (i = 0; i < source->contacts->len; i++) {
        EContact    *old_contact = g_ptr_array_index (source->contacts, i);
        const gchar *old_uid     = e_contact_get_const (old_contact, E_CONTACT_UID);
        gint         result;

        result = find_contact_by_view_and_uid (contact_store, source->client_view_pending, old_uid);
        if (result < 0) {
            /* Contact is not in new view; removed */
            g_object_unref (old_contact);
            g_ptr_array_remove_index (source->contacts, i);
            row_deleted (contact_store, offset + i);
            i--;  /* Stay in place */
        }
    }

    /* Insertions */
    for (i = 0; i < source->contacts_pending->len; i++) {
        EContact    *new_contact = g_ptr_array_index (source->contacts_pending, i);
        const gchar *new_uid     = e_contact_get_const (new_contact, E_CONTACT_UID);
        gint         result;

        result = find_contact_by_view_and_uid (contact_store, source->client_view, new_uid);
        if (result < 0) {
            /* Contact is not in old view; inserted */
            g_ptr_array_add (source->contacts, new_contact);
            row_inserted (contact_store, offset + source->contacts->len - 1);
        } else {
            /* Contact already in old view; drop the new one */
            g_object_unref (new_contact);
        }
    }

    /* Move pending view up to current */
    stop_view (contact_store, source->client_view);
    g_object_unref (source->client_view);
    source->client_view = source->client_view_pending;
    source->client_view_pending = NULL;

    /* Free array of pending contacts (members have been either moved or unreffed) */
    g_ptr_array_free (source->contacts_pending, TRUE);
    source->contacts_pending = NULL;
}

/* --------------------- *
 * View/Query management *
 * --------------------- */

static gpointer
contact_store_stop_view_in_thread (gpointer user_data)
{
    EBookClientView *view = user_data;

    g_return_val_if_fail (E_IS_BOOK_CLIENT_VIEW (view), NULL);

    /* this does blocking D-Bus call, thus do it in a dedicated thread */
    e_book_client_view_stop (view, NULL);
    g_object_unref (view);

    return NULL;
}

static void
start_view (EContactStore *contact_store,
            EBookClientView *view)
{
    g_signal_emit (contact_store, signals[START_CLIENT_VIEW], 0, view);

    g_signal_connect_swapped (
        view, "objects-added",
        G_CALLBACK (view_contacts_added), contact_store);
    g_signal_connect_swapped (
        view, "objects-removed",
        G_CALLBACK (view_contacts_removed), contact_store);
    g_signal_connect_swapped (
        view, "objects-modified",
        G_CALLBACK (view_contacts_modified), contact_store);
    g_signal_connect_swapped (
        view, "complete",
        G_CALLBACK (view_complete), contact_store);

    e_book_client_view_start (view, NULL);
}

static void
stop_view (EContactStore *contact_store,
           EBookClientView *view)
{
    GThread *thread;

    thread = g_thread_new (NULL, contact_store_stop_view_in_thread, g_object_ref (view));
    g_thread_unref (thread);

    g_signal_handlers_disconnect_matched (
        view, G_SIGNAL_MATCH_DATA,
        0, 0, NULL, NULL, contact_store);

    g_signal_emit (contact_store, signals[STOP_CLIENT_VIEW], 0, view);
}

static void
clear_contact_ptrarray (GPtrArray *contacts)
{
    gint i;

    for (i = 0; i < contacts->len; i++) {
        EContact *contact = g_ptr_array_index (contacts, i);
        g_object_unref (contact);
    }

    g_ptr_array_set_size (contacts, 0);
}

static void
free_contact_ptrarray (GPtrArray *contacts)
{
    clear_contact_ptrarray (contacts);
    g_ptr_array_free (contacts, TRUE);
}

static void
clear_contact_source (EContactStore *contact_store,
                      ContactSource *source)
{
    gint source_index;
    gint offset;

    source_index = find_contact_source_by_pointer (contact_store, source);
    g_assert (source_index >= 0);

    offset = get_contact_source_offset (contact_store, source_index);
    g_assert (offset >= 0);

    /* Inform listeners that contacts went away */

    if (source->contacts && source->contacts->len > 0) {
        GtkTreePath *path = gtk_tree_path_new ();
        gint         i;

        gtk_tree_path_append_index (path, source->contacts->len);

        for (i = source->contacts->len - 1; i >= 0; i--) {
            EContact *contact = g_ptr_array_index (source->contacts, i);

            g_object_unref (contact);
            g_ptr_array_remove_index_fast (source->contacts, i);

            gtk_tree_path_prev (path);
            gtk_tree_model_row_deleted (GTK_TREE_MODEL (contact_store), path);
        }

        gtk_tree_path_free (path);
    }

    /* Free main and pending views, clear cached contacts */

    if (source->client_view) {
        stop_view (contact_store, source->client_view);
        g_object_unref (source->client_view);

        source->client_view = NULL;
    }

    if (source->client_view_pending) {
        stop_view (contact_store, source->client_view_pending);
        g_object_unref (source->client_view_pending);
        free_contact_ptrarray (source->contacts_pending);

        source->client_view_pending = NULL;
        source->contacts_pending  = NULL;
    }
}

static void
client_view_ready_cb (GObject *source_object,
                      GAsyncResult *result,
                      gpointer user_data)
{
    EContactStore *contact_store = user_data;
    gint source_idx;
    EBookClient *book_client;
    EBookClientView *client_view = NULL;

    g_return_if_fail (contact_store != NULL);
    g_return_if_fail (source_object != NULL);

    book_client = E_BOOK_CLIENT (source_object);
    g_return_if_fail (book_client != NULL);

    if (!e_book_client_get_view_finish (book_client, result, &client_view, NULL))
        client_view = NULL;

    source_idx = find_contact_source_by_client (contact_store, book_client);
    if (source_idx >= 0) {
        ContactSource *source;

        source = &g_array_index (contact_store->priv->contact_sources, ContactSource, source_idx);

        if (source->client_view) {
            if (source->client_view_pending) {
                stop_view (contact_store, source->client_view_pending);
                g_object_unref (source->client_view_pending);
                free_contact_ptrarray (source->contacts_pending);
            }

            source->client_view_pending = client_view;

            if (source->client_view_pending) {
                source->contacts_pending = g_ptr_array_new ();
                start_view (contact_store, client_view);
            } else {
                source->contacts_pending = NULL;
            }
        } else {
            source->client_view = client_view;

            if (source->client_view) {
                start_view (contact_store, client_view);
            }
        }
    }

    g_object_unref (contact_store);
}

static void
query_contact_source (EContactStore *contact_store,
                      ContactSource *source)
{
    gchar *query_str;

    g_assert (source->book_client != NULL);

    if (!contact_store->priv->query) {
        clear_contact_source (contact_store, source);
        return;
    }

    if (source->client_view) {
        if (source->client_view_pending) {
            stop_view (contact_store, source->client_view_pending);
            g_object_unref (source->client_view_pending);
            free_contact_ptrarray (source->contacts_pending);
            source->client_view_pending = NULL;
            source->contacts_pending = NULL;
        }
    }

    query_str = e_book_query_to_string (contact_store->priv->query);
    e_book_client_get_view (source->book_client, query_str, NULL, client_view_ready_cb, g_object_ref (contact_store));
    g_free (query_str);
}

/* ----------------- *
 * EContactStore API *
 * ----------------- */

/**
 * e_contact_store_get_client:
 * @contact_store: an #EContactStore
 * @iter: a #GtkTreeIter from @contact_store
 *
 * Gets the #EBookClient that provided the contact at @iter.
 *
 * Returns: An #EBookClient.
 *
 * Since: 3.2
 **/
EBookClient *
e_contact_store_get_client (EContactStore *contact_store,
                            GtkTreeIter *iter)
{
    gint index;

    g_return_val_if_fail (E_IS_CONTACT_STORE (contact_store), NULL);
    g_return_val_if_fail (ITER_IS_VALID (contact_store, iter), NULL);

    index = ITER_GET (iter);

    return get_book_at_row (contact_store, index);
}

/**
 * e_contact_store_get_contact:
 * @contact_store: an #EContactStore
 * @iter: a #GtkTreeIter from @contact_store
 *
 * Gets the #EContact at @iter.
 *
 * Returns: An #EContact.
 **/
EContact *
e_contact_store_get_contact (EContactStore *contact_store,
                             GtkTreeIter *iter)
{
    gint index;

    g_return_val_if_fail (E_IS_CONTACT_STORE (contact_store), NULL);
    g_return_val_if_fail (ITER_IS_VALID (contact_store, iter), NULL);

    index = ITER_GET (iter);

    return get_contact_at_row (contact_store, index);
}

/**
 * e_contact_store_find_contact:
 * @contact_store: an #EContactStore
 * @uid: a unique contact identifier
 * @iter: a destination #GtkTreeIter to set
 *
 * Sets @iter to point to the contact row matching @uid.
 *
 * Returns: %TRUE if the contact was found, and @iter was set. %FALSE otherwise.
 **/
gboolean
e_contact_store_find_contact (EContactStore *contact_store,
                              const gchar *uid,
                              GtkTreeIter *iter)
{
    gint index;

    g_return_val_if_fail (E_IS_CONTACT_STORE (contact_store), FALSE);
    g_return_val_if_fail (uid != NULL, FALSE);

    index = find_contact_by_uid (contact_store, uid);
    if (index < 0)
        return FALSE;

    ITER_SET (contact_store, iter, index);
    return TRUE;
}

/**
 * e_contact_store_get_clients:
 * @contact_store: an #EContactStore
 *
 * Gets the list of book clients that provide contacts for @contact_store.
 *
 * Returns: A #GSList of pointers to #EBookClient. The caller owns the list,
 * but not the book clients.
 *
 * Since: 3.2
 **/
GSList *
e_contact_store_get_clients (EContactStore *contact_store)
{
    GArray *array;
    GSList *client_list = NULL;
    gint i;

    g_return_val_if_fail (E_IS_CONTACT_STORE (contact_store), NULL);

    array = contact_store->priv->contact_sources;

    for (i = 0; i < array->len; i++) {
        ContactSource *source;

        source = &g_array_index (array, ContactSource, i);
        client_list = g_slist_prepend (client_list, source->book_client);
    }

    return client_list;
}

/**
 * e_contact_store_add_client:
 * @contact_store: an #EContactStore
 * @book_client: an #EBookClient
 *
 * Adds @book_client to the list of clients that provide contacts for
 * @contact_store.  The @contact_store adds a reference to @book_client,
 * if added.
 *
 * Since: 3.2
 **/
void
e_contact_store_add_client (EContactStore *contact_store,
                            EBookClient *book_client)
{
    GArray *array;
    ContactSource source;
    ContactSource *indexed_source;

    g_return_if_fail (E_IS_CONTACT_STORE (contact_store));
    g_return_if_fail (E_IS_BOOK_CLIENT (book_client));

    /* Return silently if we already have this EBookClient. */
    if (find_contact_source_by_client (contact_store, book_client) >= 0)
        return;

    array = contact_store->priv->contact_sources;

    memset (&source, 0, sizeof (ContactSource));
    source.book_client = g_object_ref (book_client);
    source.contacts = g_ptr_array_new ();
    g_array_append_val (array, source);

    indexed_source = &g_array_index (array, ContactSource, array->len - 1);

    query_contact_source (contact_store, indexed_source);
}

/**
 * e_contact_store_remove_client:
 * @contact_store: an #EContactStore
 * @book_client: an #EBookClient
 *
 * Removes @book_client from the list of clients that provide contacts for
 * @contact_store.
 *
 * Returns: whether @book_client was found and removed
 *
 * Since: 3.2
 **/
gboolean
e_contact_store_remove_client (EContactStore *contact_store,
                               EBookClient *book_client)
{
    GArray *array;
    ContactSource *source;
    gint source_index;

    g_return_val_if_fail (E_IS_CONTACT_STORE (contact_store), FALSE);
    g_return_val_if_fail (E_IS_BOOK_CLIENT (book_client), FALSE);

    source_index = find_contact_source_by_client (contact_store, book_client);
    if (source_index < 0)
        return FALSE;

    array = contact_store->priv->contact_sources;

    source = &g_array_index (array, ContactSource, source_index);
    clear_contact_source (contact_store, source);
    free_contact_ptrarray (source->contacts);
    g_object_unref (book_client);

    g_array_remove_index (array, source_index);  /* Preserve order */

    return TRUE;
}

/**
 * e_contact_store_set_query:
 * @contact_store: an #EContactStore
 * @book_query: an #EBookQuery
 *
 * Sets @book_query to be the query used to fetch contacts from the books
 * assigned to @contact_store.
 **/
void
e_contact_store_set_query (EContactStore *contact_store,
                           EBookQuery *book_query)
{
    GArray *array;
    gint i;

    g_return_if_fail (E_IS_CONTACT_STORE (contact_store));

    if (book_query == contact_store->priv->query)
        return;

    if (contact_store->priv->query)
        e_book_query_unref (contact_store->priv->query);

    contact_store->priv->query = book_query;
    if (book_query)
        e_book_query_ref (book_query);

    /* Query books */
    array = contact_store->priv->contact_sources;
    for (i = 0; i < array->len; i++) {
        ContactSource *contact_source;

        contact_source = &g_array_index (array, ContactSource, i);
        query_contact_source (contact_store, contact_source);
    }
}

/**
 * e_contact_store_peek_query:
 * @contact_store: an #EContactStore
 *
 * Gets the query that's being used to fetch contacts from the books
 * assigned to @contact_store.
 *
 * Returns: The #EBookQuery being used.
 **/
EBookQuery *
e_contact_store_peek_query (EContactStore *contact_store)
{
    g_return_val_if_fail (E_IS_CONTACT_STORE (contact_store), NULL);

    return contact_store->priv->query;
}

/* ---------------- *
 * GtkTreeModel API *
 * ---------------- */

static GtkTreeModelFlags
e_contact_store_get_flags (GtkTreeModel *tree_model)
{
    g_return_val_if_fail (E_IS_CONTACT_STORE (tree_model), 0);

    return GTK_TREE_MODEL_LIST_ONLY;
}

static gint
e_contact_store_get_n_columns (GtkTreeModel *tree_model)
{
    g_return_val_if_fail (E_IS_CONTACT_STORE (tree_model), 0);

    return E_CONTACT_FIELD_LAST;
}

static GType
get_column_type (EContactStore *contact_store,
                 gint column)
{
    const gchar  *field_name;
    GObjectClass *contact_class;
    GParamSpec   *param_spec;
    GType         value_type;

    /* Silently suppress requests for columns lower than the first EContactField.
     * GtkTreeView automatically queries the type of all columns up to the maximum
     * provided, and we have to return a valid value type, so let it be a generic
     * pointer. */
    if (column < E_CONTACT_FIELD_FIRST) {
        return G_TYPE_POINTER;
    }

    field_name = e_contact_field_name (column);
    contact_class = g_type_class_ref (E_TYPE_CONTACT);
    param_spec = g_object_class_find_property (contact_class, field_name);
    value_type = G_PARAM_SPEC_VALUE_TYPE (param_spec);
    g_type_class_unref (contact_class);

    return value_type;
}

static GType
e_contact_store_get_column_type (GtkTreeModel *tree_model,
                                 gint index)
{
    EContactStore *contact_store = E_CONTACT_STORE (tree_model);

    g_return_val_if_fail (E_IS_CONTACT_STORE (tree_model), G_TYPE_INVALID);
    g_return_val_if_fail (index >= 0 && index < E_CONTACT_FIELD_LAST, G_TYPE_INVALID);

    return get_column_type (contact_store, index);
}

static gboolean
e_contact_store_get_iter (GtkTreeModel *tree_model,
                          GtkTreeIter *iter,
                          GtkTreePath *path)
{
    EContactStore *contact_store = E_CONTACT_STORE (tree_model);
    gint           index;

    g_return_val_if_fail (E_IS_CONTACT_STORE (tree_model), FALSE);
    g_return_val_if_fail (gtk_tree_path_get_depth (path) > 0, FALSE);

    index = gtk_tree_path_get_indices (path)[0];
    if (index >= count_contacts (contact_store))
        return FALSE;

    ITER_SET (contact_store, iter, index);
    return TRUE;
}

static GtkTreePath *
e_contact_store_get_path (GtkTreeModel *tree_model,
                          GtkTreeIter *iter)
{
    EContactStore *contact_store = E_CONTACT_STORE (tree_model);
    GtkTreePath   *path;
    gint           index;

    g_return_val_if_fail (E_IS_CONTACT_STORE (tree_model), NULL);
    g_return_val_if_fail (ITER_IS_VALID (contact_store, iter), NULL);

    index = ITER_GET (iter);
    path = gtk_tree_path_new ();
    gtk_tree_path_append_index (path, index);

    return path;
}

static gboolean
e_contact_store_iter_next (GtkTreeModel *tree_model,
                           GtkTreeIter *iter)
{
    EContactStore *contact_store = E_CONTACT_STORE (tree_model);
    gint           index;

    g_return_val_if_fail (E_IS_CONTACT_STORE (tree_model), FALSE);
    g_return_val_if_fail (ITER_IS_VALID (contact_store, iter), FALSE);

    index = ITER_GET (iter);

    if (index + 1 < count_contacts (contact_store)) {
        ITER_SET (contact_store, iter, index + 1);
        return TRUE;
    }

    return FALSE;
}

static gboolean
e_contact_store_iter_children (GtkTreeModel *tree_model,
                               GtkTreeIter *iter,
                               GtkTreeIter *parent)
{
    EContactStore *contact_store = E_CONTACT_STORE (tree_model);

    g_return_val_if_fail (E_IS_CONTACT_STORE (tree_model), FALSE);

    /* This is a list, nodes have no children. */
    if (parent)
        return FALSE;

    /* But if parent == NULL we return the list itself as children of the root. */
    if (count_contacts (contact_store) <= 0)
        return FALSE;

    ITER_SET (contact_store, iter, 0);
    return TRUE;
}

static gboolean
e_contact_store_iter_has_child (GtkTreeModel *tree_model,
                                GtkTreeIter *iter)
{
    g_return_val_if_fail (E_IS_CONTACT_STORE (tree_model), FALSE);

    if (iter == NULL)
        return TRUE;

    return FALSE;
}

static gint
e_contact_store_iter_n_children (GtkTreeModel *tree_model,
                                 GtkTreeIter *iter)
{
    EContactStore *contact_store = E_CONTACT_STORE (tree_model);

    g_return_val_if_fail (E_IS_CONTACT_STORE (tree_model), -1);

    if (iter == NULL)
        return count_contacts (contact_store);

    g_return_val_if_fail (ITER_IS_VALID (contact_store, iter), -1);
    return 0;
}

static gboolean
e_contact_store_iter_nth_child (GtkTreeModel *tree_model,
                                GtkTreeIter *iter,
                                GtkTreeIter *parent,
                                gint n)
{
    EContactStore *contact_store = E_CONTACT_STORE (tree_model);

    g_return_val_if_fail (E_IS_CONTACT_STORE (tree_model), FALSE);

    if (parent)
        return FALSE;

    if (n < count_contacts (contact_store)) {
        ITER_SET (contact_store, iter, n);
        return TRUE;
    }

    return FALSE;
}

static gboolean
e_contact_store_iter_parent (GtkTreeModel *tree_model,
                             GtkTreeIter *iter,
                             GtkTreeIter *child)
{
    return FALSE;
}

static void
e_contact_store_get_value (GtkTreeModel *tree_model,
                           GtkTreeIter *iter,
                           gint column,
                           GValue *value)
{
    EContactStore *contact_store = E_CONTACT_STORE (tree_model);
    EContact      *contact;
    const gchar   *field_name;
    gint           row;

    g_return_if_fail (E_IS_CONTACT_STORE (tree_model));
    g_return_if_fail (column < E_CONTACT_FIELD_LAST);
    g_return_if_fail (ITER_IS_VALID (contact_store, iter));

    g_value_init (value, get_column_type (contact_store, column));

    row = ITER_GET (iter);
    contact = get_contact_at_row (contact_store, row);
    if (!contact || column < E_CONTACT_FIELD_FIRST)
        return;

    field_name = e_contact_field_name (column);
    g_object_get_property (G_OBJECT (contact), field_name, value);
}