/*
 * This file Copyright (C) 2012-2014 Mnemosyne LLC
 *
 * It may be used under the GNU GPL versions 2 or 3
 * or any future license endorsed by Mnemosyne LLC.
 *
 */

#include <stdlib.h> /* qsort() */

#include <gtk/gtk.h>
#include <glib/gi18n.h>

#include <libtransmission/transmission.h>
#include <libtransmission/utils.h>

#include "favicon.h" /* gtr_get_favicon() */
#include "filter.h"
#include "hig.h" /* GUI_PAD */
#include "tr-core.h" /* MC_TORRENT */
#include "util.h" /* gtr_get_host_from_url() */

static GQuark DIRTY_KEY = 0;
static GQuark SESSION_KEY = 0;
static GQuark TEXT_KEY = 0;
static GQuark TORRENT_MODEL_KEY = 0;

/***
****
****  TRACKERS
****
***/

enum
{
    TRACKER_FILTER_TYPE_ALL,
    TRACKER_FILTER_TYPE_HOST,
    TRACKER_FILTER_TYPE_SEPARATOR,
};

enum
{
    TRACKER_FILTER_COL_NAME, /* human-readable name; ie, Legaltorrents */
    TRACKER_FILTER_COL_COUNT, /* how many matches there are */
    TRACKER_FILTER_COL_TYPE,
    TRACKER_FILTER_COL_HOST, /* pattern-matching text; ie, legaltorrents.com */
    TRACKER_FILTER_COL_PIXBUF,
    TRACKER_FILTER_N_COLS
};

static int pstrcmp(void const* a, void const* b)
{
    return g_strcmp0(*(char const* const*)a, *(char const* const*)b);
}

/* human-readable name; ie, Legaltorrents */
static char* get_name_from_host(char const* host)
{
    char* name;
    char const* dot = strrchr(host, '.');

    if (tr_addressIsIP(host))
    {
        name = g_strdup(host);
    }
    else if (dot != nullptr)
    {
        name = g_strndup(host, dot - host);
    }
    else
    {
        name = g_strdup(host);
    }

    *name = g_ascii_toupper(*name);

    return name;
}

static void tracker_model_update_count(GtkTreeStore* store, GtkTreeIter* iter, int n)
{
    int count;
    GtkTreeModel* model = GTK_TREE_MODEL(store);
    gtk_tree_model_get(model, iter, TRACKER_FILTER_COL_COUNT, &count, -1);

    if (n != count)
    {
        gtk_tree_store_set(store, iter, TRACKER_FILTER_COL_COUNT, n, -1);
    }
}

static void favicon_ready_cb(gpointer pixbuf, gpointer vreference)
{
    GtkTreeIter iter;
    auto* reference = static_cast<GtkTreeRowReference*>(vreference);

    if (pixbuf != nullptr)
    {
        GtkTreePath* path = gtk_tree_row_reference_get_path(reference);
        GtkTreeModel* model = gtk_tree_row_reference_get_model(reference);

        if (gtk_tree_model_get_iter(model, &iter, path))
        {
            gtk_tree_store_set(GTK_TREE_STORE(model), &iter, TRACKER_FILTER_COL_PIXBUF, pixbuf, -1);
        }

        gtk_tree_path_free(path);

        g_object_unref(pixbuf);
    }

    gtk_tree_row_reference_free(reference);
}

static gboolean tracker_filter_model_update(gpointer gstore)
{
    GObject* o = G_OBJECT(gstore);
    g_object_steal_qdata(o, DIRTY_KEY);

    /* Walk through all the torrents, tallying how many matches there are
     * for the various categories. Also make a sorted list of all tracker
     * hosts s.t. we can merge it with the existing list */
    int num_torrents = 0;
    GPtrArray* hosts = g_ptr_array_new();
    GStringChunk* strings = g_string_chunk_new(4096);
    GHashTable* hosts_hash = g_hash_table_new_full(g_str_hash, g_str_equal, nullptr, g_free);
    GtkTreeModel* tmodel = GTK_TREE_MODEL(g_object_get_qdata(o, TORRENT_MODEL_KEY));
    GtkTreeIter iter;
    if (gtk_tree_model_iter_nth_child(tmodel, &iter, nullptr, 0))
    {
        do
        {
            tr_torrent const* tor;
            gtk_tree_model_get(tmodel, &iter, MC_TORRENT, &tor, -1);
            tr_info const* const inf = tr_torrentInfo(tor);

            int keyCount = 0;
            char** const keys = g_new(char*, inf->trackerCount);

            for (unsigned int i = 0; i < inf->trackerCount; ++i)
            {
                char name[1024];
                gtr_get_host_from_url(name, sizeof(name), inf->trackers[i].announce);
                char* const key = g_string_chunk_insert_const(strings, name);

                auto* count = static_cast<int*>(g_hash_table_lookup(hosts_hash, key));
                if (count == nullptr)
                {
                    count = tr_new0(int, 1);
                    g_hash_table_insert(hosts_hash, key, count);
                    g_ptr_array_add(hosts, key);
                }

                bool found = false;

                for (int k = 0; !found && k < keyCount; ++k)
                {
                    found = g_strcmp0(keys[k], key) == 0;
                }

                if (!found)
                {
                    keys[keyCount++] = key;
                }
            }

            for (int i = 0; i < keyCount; ++i)
            {
                auto* incrementme = static_cast<int*>(g_hash_table_lookup(hosts_hash, keys[i]));
                ++*incrementme;
            }

            g_free(keys);

            ++num_torrents;
        } while (gtk_tree_model_iter_next(tmodel, &iter));
    }

    qsort(hosts->pdata, hosts->len, sizeof(char*), pstrcmp);

    // update the "all" count
    GtkTreeStore* store = GTK_TREE_STORE(gstore);
    GtkTreeModel* model = GTK_TREE_MODEL(gstore);
    if (gtk_tree_model_iter_children(model, &iter, nullptr))
    {
        tracker_model_update_count(store, &iter, num_torrents);
    }

    int store_pos = 2; // offset past the "All" and the separator
    guint i = 0;
    for (;;)
    {
        // are we done yet?
        gboolean const new_hosts_done = i >= hosts->len;
        gboolean const old_hosts_done = !gtk_tree_model_iter_nth_child(model, &iter, nullptr, store_pos);
        if (new_hosts_done && old_hosts_done)
        {
            break;
        }

        // decide what to do
        gboolean remove_row = FALSE;
        gboolean insert_row = FALSE;
        if (new_hosts_done)
        {
            remove_row = TRUE;
        }
        else if (old_hosts_done)
        {
            insert_row = TRUE;
        }
        else
        {
            char* host;
            gtk_tree_model_get(model, &iter, TRACKER_FILTER_COL_HOST, &host, -1);
            int const cmp = g_strcmp0(host, static_cast<char const*>(hosts->pdata[i]));

            if (cmp < 0)
            {
                remove_row = TRUE;
            }
            else if (cmp > 0)
            {
                insert_row = TRUE;
            }

            g_free(host);
        }

        // do something
        if (remove_row)
        {
            gtk_tree_store_remove(store, &iter);
        }
        else if (insert_row)
        {
            GtkTreeIter add;
            GtkTreePath* path;
            GtkTreeRowReference* reference;
            auto* session = static_cast<tr_session*>(g_object_get_qdata(G_OBJECT(store), SESSION_KEY));
            auto const* host = static_cast<char const*>(hosts->pdata[i]);
            char* name = get_name_from_host(host);
            int const count = *(int*)g_hash_table_lookup(hosts_hash, host);
            gtk_tree_store_insert_with_values(
                store,
                &add,
                nullptr,
                store_pos,
                TR_ARG_TUPLE(TRACKER_FILTER_COL_HOST, host),
                TR_ARG_TUPLE(TRACKER_FILTER_COL_NAME, name),
                TR_ARG_TUPLE(TRACKER_FILTER_COL_COUNT, count),
                TR_ARG_TUPLE(TRACKER_FILTER_COL_TYPE, TRACKER_FILTER_TYPE_HOST),
                -1);
            path = gtk_tree_model_get_path(model, &add);
            reference = gtk_tree_row_reference_new(model, path);
            gtr_get_favicon(session, host, favicon_ready_cb, reference);
            gtk_tree_path_free(path);
            g_free(name);
            ++store_pos;
            ++i;
        }
        else // update row
        {
            auto const* const host = static_cast<char const*>(hosts->pdata[i]);
            int const count = *(int*)g_hash_table_lookup(hosts_hash, host);
            tracker_model_update_count(store, &iter, count);
            ++store_pos;
            ++i;
        }
    }

    // cleanup
    g_ptr_array_free(hosts, TRUE);
    g_hash_table_unref(hosts_hash);
    g_string_chunk_free(strings);
    return G_SOURCE_REMOVE;
}

static GtkTreeModel* tracker_filter_model_new(GtkTreeModel* tmodel)
{
    GtkTreeStore* store = gtk_tree_store_new(
        TRACKER_FILTER_N_COLS,
        G_TYPE_STRING,
        G_TYPE_INT,
        G_TYPE_INT,
        G_TYPE_STRING,
        GDK_TYPE_PIXBUF);

    gtk_tree_store_insert_with_values(
        store,
        nullptr,
        nullptr,
        -1,
        TR_ARG_TUPLE(TRACKER_FILTER_COL_NAME, _("All")),
        TR_ARG_TUPLE(TRACKER_FILTER_COL_TYPE, TRACKER_FILTER_TYPE_ALL),
        -1);
    gtk_tree_store_insert_with_values(
        store,
        nullptr,
        nullptr,
        -1,
        TR_ARG_TUPLE(TRACKER_FILTER_COL_TYPE, TRACKER_FILTER_TYPE_SEPARATOR),
        -1);

    g_object_set_qdata(G_OBJECT(store), TORRENT_MODEL_KEY, tmodel);
    tracker_filter_model_update(store);
    return GTK_TREE_MODEL(store);
}

static gboolean is_it_a_separator(GtkTreeModel* m, GtkTreeIter* iter, gpointer data)
{
    TR_UNUSED(data);

    int type;
    gtk_tree_model_get(m, iter, TRACKER_FILTER_COL_TYPE, &type, -1);
    return type == TRACKER_FILTER_TYPE_SEPARATOR;
}

static void tracker_model_update_idle(gpointer tracker_model)
{
    GObject* o = G_OBJECT(tracker_model);
    gboolean const pending = g_object_get_qdata(o, DIRTY_KEY) != nullptr;

    if (!pending)
    {
        GSourceFunc func = tracker_filter_model_update;
        g_object_set_qdata(o, DIRTY_KEY, GINT_TO_POINTER(1));
        gdk_threads_add_idle(func, tracker_model);
    }
}

static void torrent_model_row_changed(GtkTreeModel* tmodel, GtkTreePath* path, GtkTreeIter* iter, gpointer tracker_model)
{
    TR_UNUSED(tmodel);
    TR_UNUSED(path);
    TR_UNUSED(iter);

    tracker_model_update_idle(tracker_model);
}

static void torrent_model_row_deleted_cb(GtkTreeModel* tmodel, GtkTreePath* path, gpointer tracker_model)
{
    TR_UNUSED(tmodel);
    TR_UNUSED(path);

    tracker_model_update_idle(tracker_model);
}

static void render_pixbuf_func(
    GtkCellLayout* cell_layout,
    GtkCellRenderer* cell_renderer,
    GtkTreeModel* tree_model,
    GtkTreeIter* iter,
    gpointer data)
{
    TR_UNUSED(cell_layout);
    TR_UNUSED(data);

    int type;
    int width;

    gtk_tree_model_get(tree_model, iter, TRACKER_FILTER_COL_TYPE, &type, -1);
    width = (type == TRACKER_FILTER_TYPE_HOST) ? 20 : 0;
    g_object_set(cell_renderer, "width", width, nullptr);
}

static void render_number_func(
    GtkCellLayout* cell_layout,
    GtkCellRenderer* cell_renderer,
    GtkTreeModel* tree_model,
    GtkTreeIter* iter,
    gpointer data)
{
    TR_UNUSED(cell_layout);
    TR_UNUSED(data);

    int count;
    char buf[32];

    gtk_tree_model_get(tree_model, iter, TRACKER_FILTER_COL_COUNT, &count, -1);

    if (count >= 0)
    {
        g_snprintf(buf, sizeof(buf), "%'d", count);
    }
    else
    {
        *buf = '\0';
    }

    g_object_set(cell_renderer, "text", buf, nullptr);
}

static GtkCellRenderer* number_renderer_new(void)
{
    GtkCellRenderer* r = gtk_cell_renderer_text_new();

    g_object_set(
        G_OBJECT(r),
        TR_ARG_TUPLE("alignment", PANGO_ALIGN_RIGHT),
        TR_ARG_TUPLE("weight", PANGO_WEIGHT_ULTRALIGHT),
        TR_ARG_TUPLE("xalign", 1.0),
        TR_ARG_TUPLE("xpad", GUI_PAD),
        nullptr);

    return r;
}

static void disconnect_cat_model_callbacks(gpointer tmodel, GObject* cat_model)
{
    g_signal_handlers_disconnect_by_func(tmodel, reinterpret_cast<gpointer>(torrent_model_row_changed), cat_model);
    g_signal_handlers_disconnect_by_func(tmodel, reinterpret_cast<gpointer>(torrent_model_row_deleted_cb), cat_model);
}

static GtkWidget* tracker_combo_box_new(GtkTreeModel* tmodel)
{
    GtkWidget* c;
    GtkCellRenderer* r;
    GtkTreeModel* cat_model;
    GtkCellLayout* c_cell_layout;
    GtkComboBox* c_combo_box;

    /* create the tracker combobox */
    cat_model = tracker_filter_model_new(tmodel);
    c = gtk_combo_box_new_with_model(cat_model);
    c_combo_box = GTK_COMBO_BOX(c);
    c_cell_layout = GTK_CELL_LAYOUT(c);
    gtk_combo_box_set_row_separator_func(c_combo_box, is_it_a_separator, nullptr, nullptr);
    gtk_combo_box_set_active(c_combo_box, 0);

    r = gtk_cell_renderer_pixbuf_new();
    gtk_cell_layout_pack_start(c_cell_layout, r, FALSE);
    gtk_cell_layout_set_cell_data_func(c_cell_layout, r, render_pixbuf_func, nullptr, nullptr);
    gtk_cell_layout_set_attributes(c_cell_layout, r, "pixbuf", TRACKER_FILTER_COL_PIXBUF, nullptr);

    r = gtk_cell_renderer_text_new();
    gtk_cell_layout_pack_start(c_cell_layout, r, FALSE);
    gtk_cell_layout_set_attributes(c_cell_layout, r, "text", TRACKER_FILTER_COL_NAME, nullptr);

    r = number_renderer_new();
    gtk_cell_layout_pack_end(c_cell_layout, r, TRUE);
    gtk_cell_layout_set_cell_data_func(c_cell_layout, r, render_number_func, nullptr, nullptr);

    g_object_weak_ref(G_OBJECT(cat_model), disconnect_cat_model_callbacks, tmodel);
    g_signal_connect(tmodel, "row-changed", G_CALLBACK(torrent_model_row_changed), cat_model);
    g_signal_connect(tmodel, "row-inserted", G_CALLBACK(torrent_model_row_changed), cat_model);
    g_signal_connect(tmodel, "row-deleted", G_CALLBACK(torrent_model_row_deleted_cb), cat_model);

    return c;
}

static gboolean test_tracker(tr_torrent const* tor, int active_tracker_type, char const* host)
{
    gboolean matches = TRUE;

    if (active_tracker_type == TRACKER_FILTER_TYPE_HOST)
    {
        char tmp[1024];
        tr_info const* const inf = tr_torrentInfo(tor);

        matches = FALSE;

        for (unsigned int i = 0; !matches && i < inf->trackerCount; ++i)
        {
            gtr_get_host_from_url(tmp, sizeof(tmp), inf->trackers[i].announce);
            matches = g_strcmp0(tmp, host) == 0;
        }
    }

    return matches;
}

/***
****
****  ACTIVITY
****
***/

enum
{
    ACTIVITY_FILTER_ALL,
    ACTIVITY_FILTER_DOWNLOADING,
    ACTIVITY_FILTER_SEEDING,
    ACTIVITY_FILTER_ACTIVE,
    ACTIVITY_FILTER_PAUSED,
    ACTIVITY_FILTER_FINISHED,
    ACTIVITY_FILTER_VERIFYING,
    ACTIVITY_FILTER_ERROR,
    ACTIVITY_FILTER_SEPARATOR
};

enum
{
    ACTIVITY_FILTER_COL_NAME,
    ACTIVITY_FILTER_COL_COUNT,
    ACTIVITY_FILTER_COL_TYPE,
    ACTIVITY_FILTER_COL_ICON_NAME,
    ACTIVITY_FILTER_N_COLS
};

static gboolean activity_is_it_a_separator(GtkTreeModel* m, GtkTreeIter* i, gpointer d)
{
    TR_UNUSED(d);

    int type;
    gtk_tree_model_get(m, i, ACTIVITY_FILTER_COL_TYPE, &type, -1);
    return type == ACTIVITY_FILTER_SEPARATOR;
}

static gboolean test_torrent_activity(tr_torrent* tor, int type)
{
    tr_stat const* st = tr_torrentStatCached(tor);

    switch (type)
    {
    case ACTIVITY_FILTER_DOWNLOADING:
        return st->activity == TR_STATUS_DOWNLOAD || st->activity == TR_STATUS_DOWNLOAD_WAIT;

    case ACTIVITY_FILTER_SEEDING:
        return st->activity == TR_STATUS_SEED || st->activity == TR_STATUS_SEED_WAIT;

    case ACTIVITY_FILTER_ACTIVE:
        return st->peersSendingToUs > 0 || st->peersGettingFromUs > 0 || st->webseedsSendingToUs > 0 ||
            st->activity == TR_STATUS_CHECK;

    case ACTIVITY_FILTER_PAUSED:
        return st->activity == TR_STATUS_STOPPED;

    case ACTIVITY_FILTER_FINISHED:
        return st->finished == TRUE;

    case ACTIVITY_FILTER_VERIFYING:
        return st->activity == TR_STATUS_CHECK || st->activity == TR_STATUS_CHECK_WAIT;

    case ACTIVITY_FILTER_ERROR:
        return st->error != 0;

    default: /* ACTIVITY_FILTER_ALL */
        return TRUE;
    }
}

static void status_model_update_count(GtkListStore* store, GtkTreeIter* iter, int n)
{
    int count;
    GtkTreeModel* model = GTK_TREE_MODEL(store);
    gtk_tree_model_get(model, iter, ACTIVITY_FILTER_COL_COUNT, &count, -1);

    if (n != count)
    {
        gtk_list_store_set(store, iter, ACTIVITY_FILTER_COL_COUNT, n, -1);
    }
}

static gboolean activity_filter_model_update(gpointer gstore)
{
    GtkTreeIter iter;
    GObject* o = G_OBJECT(gstore);
    GtkListStore* store = GTK_LIST_STORE(gstore);
    GtkTreeModel* model = GTK_TREE_MODEL(store);
    GtkTreeModel* tmodel = GTK_TREE_MODEL(g_object_get_qdata(o, TORRENT_MODEL_KEY));

    g_object_steal_qdata(o, DIRTY_KEY);

    if (gtk_tree_model_iter_nth_child(model, &iter, nullptr, 0))
    {
        do
        {
            int hits;
            int type;
            GtkTreeIter torrent_iter;

            gtk_tree_model_get(model, &iter, ACTIVITY_FILTER_COL_TYPE, &type, -1);

            hits = 0;

            if (gtk_tree_model_iter_nth_child(tmodel, &torrent_iter, nullptr, 0))
            {
                do
                {
                    tr_torrent* tor;
                    gtk_tree_model_get(tmodel, &torrent_iter, MC_TORRENT, &tor, -1);

                    if (test_torrent_activity(tor, type))
                    {
                        ++hits;
                    }
                } while (gtk_tree_model_iter_next(tmodel, &torrent_iter));
            }

            status_model_update_count(store, &iter, hits);
        } while (gtk_tree_model_iter_next(model, &iter));
    }

    return G_SOURCE_REMOVE;
}

static GtkTreeModel* activity_filter_model_new(GtkTreeModel* tmodel)
{
    struct
    {
        int type;
        char const* context;
        char const* name;
        char const* icon_name;
    } types[] = {
        { ACTIVITY_FILTER_ALL, nullptr, N_("All"), nullptr },
        { ACTIVITY_FILTER_SEPARATOR, nullptr, nullptr, nullptr },
        { ACTIVITY_FILTER_ACTIVE, nullptr, N_("Active"), "system-run" },
        { ACTIVITY_FILTER_DOWNLOADING, "Verb", NC_("Verb", "Downloading"), "network-receive" },
        { ACTIVITY_FILTER_SEEDING, "Verb", NC_("Verb", "Seeding"), "network-transmit" },
        { ACTIVITY_FILTER_PAUSED, nullptr, N_("Paused"), "media-playback-pause" },
        { ACTIVITY_FILTER_FINISHED, nullptr, N_("Finished"), "media-playback-stop" },
        { ACTIVITY_FILTER_VERIFYING, "Verb", NC_("Verb", "Verifying"), "view-refresh" },
        { ACTIVITY_FILTER_ERROR, nullptr, N_("Error"), "dialog-error" },
    };

    GtkListStore* store = gtk_list_store_new(ACTIVITY_FILTER_N_COLS, G_TYPE_STRING, G_TYPE_INT, G_TYPE_INT, G_TYPE_STRING);

    for (size_t i = 0; i < G_N_ELEMENTS(types); ++i)
    {
        char const* name = types[i].context != nullptr ? g_dpgettext2(nullptr, types[i].context, types[i].name) :
                                                         _(types[i].name);
        gtk_list_store_insert_with_values(
            store,
            nullptr,
            -1,
            TR_ARG_TUPLE(ACTIVITY_FILTER_COL_NAME, name),
            TR_ARG_TUPLE(ACTIVITY_FILTER_COL_TYPE, types[i].type),
            TR_ARG_TUPLE(ACTIVITY_FILTER_COL_ICON_NAME, types[i].icon_name),
            -1);
    }

    g_object_set_qdata(G_OBJECT(store), TORRENT_MODEL_KEY, tmodel);
    activity_filter_model_update(store);
    return GTK_TREE_MODEL(store);
}

static void render_activity_pixbuf_func(
    GtkCellLayout* cell_layout,
    GtkCellRenderer* cell_renderer,
    GtkTreeModel* tree_model,
    GtkTreeIter* iter,
    gpointer data)
{
    TR_UNUSED(cell_layout);
    TR_UNUSED(data);

    int type;
    int width;
    int ypad;

    gtk_tree_model_get(tree_model, iter, ACTIVITY_FILTER_COL_TYPE, &type, -1);
    width = type == ACTIVITY_FILTER_ALL ? 0 : 20;
    ypad = type == ACTIVITY_FILTER_ALL ? 0 : 2;

    g_object_set(cell_renderer, "width", width, "ypad", ypad, nullptr);
}

static void activity_model_update_idle(gpointer activity_model)
{
    GObject* o = G_OBJECT(activity_model);
    gboolean const pending = g_object_get_qdata(o, DIRTY_KEY) != nullptr;

    if (!pending)
    {
        GSourceFunc func = activity_filter_model_update;
        g_object_set_qdata(o, DIRTY_KEY, GINT_TO_POINTER(1));
        gdk_threads_add_idle(func, activity_model);
    }
}

static void activity_torrent_model_row_changed(
    GtkTreeModel const* tmodel,
    GtkTreePath const* path,
    GtkTreeIter const* iter,
    gpointer activity_model)
{
    TR_UNUSED(tmodel);
    TR_UNUSED(path);
    TR_UNUSED(iter);

    activity_model_update_idle(activity_model);
}

static void activity_torrent_model_row_deleted_cb(GtkTreeModel const* tmodel, GtkTreePath const* path, gpointer activity_model)
{
    TR_UNUSED(tmodel);
    TR_UNUSED(path);

    activity_model_update_idle(activity_model);
}

static void disconnect_activity_model_callbacks(gpointer tmodel, GObject* cat_model)
{
    g_signal_handlers_disconnect_by_func(tmodel, reinterpret_cast<gpointer>(activity_torrent_model_row_changed), cat_model);
    g_signal_handlers_disconnect_by_func(tmodel, reinterpret_cast<gpointer>(activity_torrent_model_row_deleted_cb), cat_model);
}

static GtkWidget* activity_combo_box_new(GtkTreeModel* tmodel)
{
    GtkWidget* c;
    GtkCellRenderer* r;
    GtkTreeModel* activity_model;
    GtkComboBox* c_combo_box;
    GtkCellLayout* c_cell_layout;

    activity_model = activity_filter_model_new(tmodel);
    c = gtk_combo_box_new_with_model(activity_model);
    c_combo_box = GTK_COMBO_BOX(c);
    c_cell_layout = GTK_CELL_LAYOUT(c);
    gtk_combo_box_set_row_separator_func(c_combo_box, activity_is_it_a_separator, nullptr, nullptr);
    gtk_combo_box_set_active(c_combo_box, 0);

    r = gtk_cell_renderer_pixbuf_new();
    gtk_cell_layout_pack_start(c_cell_layout, r, FALSE);
    gtk_cell_layout_set_attributes(c_cell_layout, r, TR_ARG_TUPLE("icon-name", ACTIVITY_FILTER_COL_ICON_NAME), nullptr);
    gtk_cell_layout_set_cell_data_func(c_cell_layout, r, render_activity_pixbuf_func, nullptr, nullptr);

    r = gtk_cell_renderer_text_new();
    gtk_cell_layout_pack_start(c_cell_layout, r, TRUE);
    gtk_cell_layout_set_attributes(c_cell_layout, r, TR_ARG_TUPLE("text", ACTIVITY_FILTER_COL_NAME), nullptr);

    r = number_renderer_new();
    gtk_cell_layout_pack_end(c_cell_layout, r, TRUE);
    gtk_cell_layout_set_cell_data_func(c_cell_layout, r, render_number_func, nullptr, nullptr);

    g_object_weak_ref(G_OBJECT(activity_model), disconnect_activity_model_callbacks, tmodel);
    g_signal_connect(tmodel, "row-changed", G_CALLBACK(activity_torrent_model_row_changed), activity_model);
    g_signal_connect(tmodel, "row-inserted", G_CALLBACK(activity_torrent_model_row_changed), activity_model);
    g_signal_connect(tmodel, "row-deleted", G_CALLBACK(activity_torrent_model_row_deleted_cb), activity_model);

    return c;
}

/****
*****
*****  ENTRY FIELD
*****
****/

static gboolean testText(tr_torrent const* tor, char const* key)
{
    gboolean ret = FALSE;

    if (tr_str_is_empty(key))
    {
        ret = TRUE;
    }
    else
    {
        tr_info const* inf = tr_torrentInfo(tor);

        /* test the torrent name... */
        char* pch = g_utf8_casefold(tr_torrentName(tor), -1);
        ret = key == nullptr || strstr(pch, key) != nullptr;
        g_free(pch);

        /* test the files... */
        for (tr_file_index_t i = 0; i < inf->fileCount && !ret; ++i)
        {
            pch = g_utf8_casefold(inf->files[i].name, -1);
            ret = key == nullptr || strstr(pch, key) != nullptr;
            g_free(pch);
        }
    }

    return ret;
}

static void entry_clear(GtkEntry* e)
{
    gtk_entry_set_text(e, "");
}

static void filter_entry_changed(GtkEditable* e, gpointer filter_model)
{
    char* pch;
    char* folded;

    pch = gtk_editable_get_chars(e, 0, -1);
    folded = g_utf8_casefold(pch, -1);
    g_strstrip(folded);
    g_object_set_qdata_full(static_cast<GObject*>(filter_model), TEXT_KEY, folded, g_free);
    g_free(pch);

    gtk_tree_model_filter_refilter(GTK_TREE_MODEL_FILTER(filter_model));
}

/*****
******
******
******
*****/

struct filter_data
{
    GtkWidget* activity;
    GtkWidget* tracker;
    GtkWidget* entry;
    GtkWidget* show_lb;
    GtkTreeModel* filter_model;
    int active_activity_type;
    int active_tracker_type;
    char* active_tracker_host;
};

static gboolean is_row_visible(GtkTreeModel* model, GtkTreeIter* iter, gpointer vdata)
{
    char const* text;
    tr_torrent* tor;
    auto* data = static_cast<filter_data*>(vdata);
    GObject* o = G_OBJECT(data->filter_model);

    gtk_tree_model_get(model, iter, MC_TORRENT, &tor, -1);

    text = (char const*)g_object_get_qdata(o, TEXT_KEY);

    return tor != nullptr && test_tracker(tor, data->active_tracker_type, data->active_tracker_host) &&
        test_torrent_activity(tor, data->active_activity_type) && testText(tor, text);
}

static void selection_changed_cb(GtkComboBox* combo, gpointer vdata)
{
    int type;
    char* host;
    GtkTreeIter iter;
    GtkTreeModel* model;
    auto* data = static_cast<filter_data*>(vdata);

    /* set data->active_activity_type from the activity combobox */
    combo = GTK_COMBO_BOX(data->activity);
    model = gtk_combo_box_get_model(combo);

    if (gtk_combo_box_get_active_iter(combo, &iter))
    {
        gtk_tree_model_get(model, &iter, ACTIVITY_FILTER_COL_TYPE, &type, -1);
    }
    else
    {
        type = ACTIVITY_FILTER_ALL;
    }

    data->active_activity_type = type;

    /* set the active tracker type & host from the tracker combobox */
    combo = GTK_COMBO_BOX(data->tracker);
    model = gtk_combo_box_get_model(combo);

    if (gtk_combo_box_get_active_iter(combo, &iter))
    {
        gtk_tree_model_get(
            model,
            &iter,
            TR_ARG_TUPLE(TRACKER_FILTER_COL_TYPE, &type),
            TR_ARG_TUPLE(TRACKER_FILTER_COL_HOST, &host),
            -1);
    }
    else
    {
        type = TRACKER_FILTER_TYPE_ALL;
        host = nullptr;
    }

    g_free(data->active_tracker_host);
    data->active_tracker_host = host;
    data->active_tracker_type = type;

    /* refilter */
    gtk_tree_model_filter_refilter(GTK_TREE_MODEL_FILTER(data->filter_model));
}

/***
****
***/

static gboolean update_count_label(gpointer gdata)
{
    char buf[512];
    int visibleCount;
    int trackerCount;
    int activityCount;
    GtkTreeModel* model;
    GtkComboBox* combo;
    GtkTreeIter iter;
    auto* data = static_cast<filter_data*>(gdata);

    /* get the visible count */
    visibleCount = gtk_tree_model_iter_n_children(data->filter_model, nullptr);

    /* get the tracker count */
    combo = GTK_COMBO_BOX(data->tracker);
    model = gtk_combo_box_get_model(combo);

    if (gtk_combo_box_get_active_iter(combo, &iter))
    {
        gtk_tree_model_get(model, &iter, TRACKER_FILTER_COL_COUNT, &trackerCount, -1);
    }
    else
    {
        trackerCount = 0;
    }

    /* get the activity count */
    combo = GTK_COMBO_BOX(data->activity);
    model = gtk_combo_box_get_model(combo);

    if (gtk_combo_box_get_active_iter(combo, &iter))
    {
        gtk_tree_model_get(model, &iter, ACTIVITY_FILTER_COL_COUNT, &activityCount, -1);
    }
    else
    {
        activityCount = 0;
    }

    /* set the text */
    if (visibleCount == MIN(activityCount, trackerCount))
    {
        g_snprintf(buf, sizeof(buf), _("_Show:"));
    }
    else
    {
        g_snprintf(buf, sizeof(buf), _("_Show %'d of:"), visibleCount);
    }

    gtk_label_set_markup_with_mnemonic(GTK_LABEL(data->show_lb), buf);

    g_object_steal_qdata(G_OBJECT(data->show_lb), DIRTY_KEY);
    return G_SOURCE_REMOVE;
}

static void update_count_label_idle(struct filter_data* data)
{
    GObject* o = G_OBJECT(data->show_lb);
    gboolean const pending = g_object_get_qdata(o, DIRTY_KEY) != nullptr;

    if (!pending)
    {
        g_object_set_qdata(o, DIRTY_KEY, GINT_TO_POINTER(1));
        gdk_threads_add_idle(update_count_label, data);
    }
}

static void on_filter_model_row_inserted(
    GtkTreeModel const* tree_model,
    GtkTreePath const* path,
    GtkTreeIter const* iter,
    gpointer data)
{
    TR_UNUSED(tree_model);
    TR_UNUSED(path);
    TR_UNUSED(iter);

    update_count_label_idle(static_cast<filter_data*>(data));
}

static void on_filter_model_row_deleted(GtkTreeModel const* tree_model, GtkTreePath const* path, gpointer data)
{
    TR_UNUSED(tree_model);
    TR_UNUSED(path);

    update_count_label_idle(static_cast<filter_data*>(data));
}

/***
****
***/

GtkWidget* gtr_filter_bar_new(tr_session* session, GtkTreeModel* tmodel, GtkTreeModel** filter_model)
{
    GtkWidget* l;
    GtkWidget* w;
    GtkWidget* h;
    GtkWidget* s;
    GtkWidget* activity;
    GtkWidget* tracker;
    GtkBox* h_box;
    struct filter_data* data;

    g_assert(DIRTY_KEY == 0);
    TEXT_KEY = g_quark_from_static_string("tr-filter-text-key");
    DIRTY_KEY = g_quark_from_static_string("tr-filter-dirty-key");
    SESSION_KEY = g_quark_from_static_string("tr-session-key");
    TORRENT_MODEL_KEY = g_quark_from_static_string("tr-filter-torrent-model-key");

    data = g_new0(struct filter_data, 1);
    data->show_lb = gtk_label_new(nullptr);
    data->activity = activity = activity_combo_box_new(tmodel);
    data->tracker = tracker = tracker_combo_box_new(tmodel);
    data->filter_model = gtk_tree_model_filter_new(tmodel, nullptr);
    g_signal_connect(data->filter_model, "row-deleted", G_CALLBACK(on_filter_model_row_deleted), data);
    g_signal_connect(data->filter_model, "row-inserted", G_CALLBACK(on_filter_model_row_inserted), data);

    g_object_set(G_OBJECT(data->tracker), "width-request", 170, nullptr);
    g_object_set_qdata(G_OBJECT(gtk_combo_box_get_model(GTK_COMBO_BOX(data->tracker))), SESSION_KEY, session);

    gtk_tree_model_filter_set_visible_func(GTK_TREE_MODEL_FILTER(data->filter_model), is_row_visible, data, g_free);

    g_signal_connect(data->tracker, "changed", G_CALLBACK(selection_changed_cb), data);
    g_signal_connect(data->activity, "changed", G_CALLBACK(selection_changed_cb), data);

    h = gtk_box_new(GTK_ORIENTATION_HORIZONTAL, GUI_PAD_SMALL);
    h_box = GTK_BOX(h);

    /* add the activity combobox */
    w = activity;
    l = data->show_lb;
    gtk_label_set_mnemonic_widget(GTK_LABEL(l), w);
    gtk_box_pack_start(h_box, l, FALSE, FALSE, 0);
    gtk_box_pack_start(h_box, w, TRUE, TRUE, 0);
#if GTK_CHECK_VERSION(3, 12, 0)
    gtk_widget_set_margin_end(w, GUI_PAD);
#else
    gtk_widget_set_margin_right(w, GUI_PAD);
#endif

    /* add the tracker combobox */
    w = tracker;
    gtk_box_pack_start(h_box, w, TRUE, TRUE, 0);
#if GTK_CHECK_VERSION(3, 12, 0)
    gtk_widget_set_margin_end(w, GUI_PAD);
#else
    gtk_widget_set_margin_right(w, GUI_PAD);
#endif

    /* add the entry field */
    s = gtk_entry_new();
    gtk_entry_set_icon_from_icon_name(GTK_ENTRY(s), GTK_ENTRY_ICON_SECONDARY, "edit-clear");
    g_signal_connect(s, "icon-release", G_CALLBACK(entry_clear), nullptr);
    gtk_box_pack_start(h_box, s, TRUE, TRUE, 0);

    g_signal_connect(s, "changed", G_CALLBACK(filter_entry_changed), data->filter_model);
    selection_changed_cb(nullptr, data);

    *filter_model = data->filter_model;
    update_count_label(data);
    return h;
}