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

   caja-clipboard-monitor.c: catch clipboard changes.

   Copyright (C) 2004 Red Hat, Inc.

   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, write to the
   Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
   Boston, MA 02110-1301, USA.

   Author: Alexander Larsson <alexl@redhat.com>
*/

#include <config.h>
#include "caja-clipboard-monitor.h"
#include "caja-file.h"

#include <eel/eel-debug.h>
#include <eel/eel-gtk-macros.h>
#include <eel/eel-glib-extensions.h>
#include <gtk/gtk.h>

/* X11 has a weakness when it comes to clipboard handling,
 * there is no way to get told when the owner of the clipboard
 * changes. This is often needed, for instance to set the
 * sensitivity of the paste menu item. We work around this
 * internally in an app by telling the clipboard monitor when
 * we changed the clipboard. Unfortunately this doesn't give
 * us perfect results, we still don't catch changes made by
 * other clients
 *
 * This is fixed with the XFIXES extensions, which recent versions
 * of Gtk+ supports as the owner_change signal on GtkClipboard. We
 * use this now, but keep the old code since not all X servers support
 * XFIXES.
 */

enum
{
    CLIPBOARD_CHANGED,
    CLIPBOARD_INFO,
    LAST_SIGNAL
};

struct CajaClipboardMonitorDetails
{
    CajaClipboardInfo *info;
};

static guint signals[LAST_SIGNAL];
static GdkAtom copied_files_atom;

G_DEFINE_TYPE (CajaClipboardMonitor, caja_clipboard_monitor, G_TYPE_OBJECT);

static CajaClipboardMonitor *clipboard_monitor = NULL;

static void
destroy_clipboard_monitor (void)
{
    if (clipboard_monitor != NULL)
    {
        g_object_unref (clipboard_monitor);
    }
}

CajaClipboardMonitor *
caja_clipboard_monitor_get (void)
{
    GtkClipboard *clipboard;

    if (clipboard_monitor == NULL)
    {
        clipboard_monitor = CAJA_CLIPBOARD_MONITOR (g_object_new (CAJA_TYPE_CLIPBOARD_MONITOR, NULL));
        eel_debug_call_at_shutdown (destroy_clipboard_monitor);

        clipboard = gtk_clipboard_get (GDK_SELECTION_CLIPBOARD);
        g_signal_connect (clipboard, "owner_change",
                          G_CALLBACK (caja_clipboard_monitor_emit_changed), NULL);
    }
    return clipboard_monitor;
}

void
caja_clipboard_monitor_emit_changed (void)
{
    CajaClipboardMonitor *monitor;

    monitor = caja_clipboard_monitor_get ();

    g_signal_emit (monitor, signals[CLIPBOARD_CHANGED], 0);
}

static CajaClipboardInfo *
caja_clipboard_info_new (GList *files,
                         gboolean cut)
{
    CajaClipboardInfo *info;

    info = g_slice_new0 (CajaClipboardInfo);
    info->files = caja_file_list_copy (files);
    info->cut = cut;

    return info;
}

static CajaClipboardInfo *
caja_clipboard_info_copy (CajaClipboardInfo *info)
{
    CajaClipboardInfo *new_info;

    new_info = NULL;

    if (info != NULL)
    {
        new_info = caja_clipboard_info_new (info->files,
                                            info->cut);
    }

    return new_info;
}

static void
caja_clipboard_info_free (CajaClipboardInfo *info)
{
    caja_file_list_free (info->files);

    g_slice_free (CajaClipboardInfo, info);
}

static void
caja_clipboard_monitor_init (CajaClipboardMonitor *monitor)
{
    monitor->details =
        G_TYPE_INSTANCE_GET_PRIVATE (monitor, CAJA_TYPE_CLIPBOARD_MONITOR,
                                     CajaClipboardMonitorDetails);
}

static void
clipboard_monitor_finalize (GObject *object)
{
    CajaClipboardMonitor *monitor;

    monitor = CAJA_CLIPBOARD_MONITOR (object);

    if (monitor->details->info != NULL)
    {
        caja_clipboard_info_free (monitor->details->info);
        monitor->details->info = NULL;
    }

    G_OBJECT_CLASS (caja_clipboard_monitor_parent_class)->finalize (object);
}

static void
caja_clipboard_monitor_class_init (CajaClipboardMonitorClass *klass)
{
    GObjectClass *object_class;

    object_class = G_OBJECT_CLASS (klass);
    object_class->finalize = clipboard_monitor_finalize;

    copied_files_atom = gdk_atom_intern ("x-special/mate-copied-files", FALSE);

    signals[CLIPBOARD_CHANGED] =
        g_signal_new ("clipboard_changed",
                      G_TYPE_FROM_CLASS (klass),
                      G_SIGNAL_RUN_LAST,
                      G_STRUCT_OFFSET (CajaClipboardMonitorClass, clipboard_changed),
                      NULL, NULL,
                      g_cclosure_marshal_VOID__VOID,
                      G_TYPE_NONE, 0);
    signals[CLIPBOARD_INFO] =
        g_signal_new ("clipboard_info",
                      G_TYPE_FROM_CLASS (klass),
                      G_SIGNAL_RUN_LAST,
                      G_STRUCT_OFFSET (CajaClipboardMonitorClass, clipboard_info),
                      NULL, NULL,
                      g_cclosure_marshal_VOID__POINTER,
                      G_TYPE_NONE,
                      1, G_TYPE_POINTER);

    g_type_class_add_private (klass, sizeof (CajaClipboardMonitorDetails));
}

void
caja_clipboard_monitor_set_clipboard_info (CajaClipboardMonitor *monitor,
        CajaClipboardInfo *info)
{
    if (monitor->details->info != NULL)
    {
        caja_clipboard_info_free (monitor->details->info);
        monitor->details->info = NULL;
    }

    monitor->details->info = caja_clipboard_info_copy (info);

    g_signal_emit (monitor, signals[CLIPBOARD_INFO], 0, monitor->details->info);

    caja_clipboard_monitor_emit_changed ();
}

CajaClipboardInfo *
caja_clipboard_monitor_get_clipboard_info (CajaClipboardMonitor *monitor)
{
    return monitor->details->info;
}

void
caja_clear_clipboard_callback (GtkClipboard *clipboard,
                               gpointer      user_data)
{
    caja_clipboard_monitor_set_clipboard_info
    (caja_clipboard_monitor_get (), NULL);
}

static char *
convert_file_list_to_string (CajaClipboardInfo *info,
                             gboolean format_for_text,
                             gsize *len)
{
    GString *uris;
    char *uri, *tmp;
    GFile *f;
    guint i;
    GList *l;

    if (format_for_text)
    {
        uris = g_string_new (NULL);
    }
    else
    {
        uris = g_string_new (info->cut ? "cut" : "copy");
    }

    for (i = 0, l = info->files; l != NULL; l = l->next, i++)
    {
        uri = caja_file_get_uri (l->data);

        if (format_for_text)
        {
            f = g_file_new_for_uri (uri);
            tmp = g_file_get_parse_name (f);
            g_object_unref (f);

            if (tmp != NULL)
            {
                g_string_append (uris, tmp);
                g_free (tmp);
            }
            else
            {
                g_string_append (uris, uri);
            }

            /* skip newline for last element */
            if (i + 1 < g_list_length (info->files))
            {
                g_string_append_c (uris, '\n');
            }
        }
        else
        {
            g_string_append_c (uris, '\n');
            g_string_append (uris, uri);
        }

        g_free (uri);
    }

    *len = uris->len;
    return g_string_free (uris, FALSE);
}

void
caja_get_clipboard_callback (GtkClipboard     *clipboard,
                             GtkSelectionData *selection_data,
                             guint             info,
                             gpointer          user_data)
{
    char **uris;
    GList *l;
    int i;
    CajaClipboardInfo *clipboard_info;
    GdkAtom target;

    clipboard_info =
        caja_clipboard_monitor_get_clipboard_info (caja_clipboard_monitor_get ());

    target = gtk_selection_data_get_target (selection_data);

    if (gtk_targets_include_uri (&target, 1))
    {
        uris = g_malloc ((g_list_length (clipboard_info->files) + 1) * sizeof (char *));
        i = 0;

        for (l = clipboard_info->files; l != NULL; l = l->next)
        {
            uris[i] = caja_file_get_uri (l->data);
            i++;
        }

        uris[i] = NULL;

        gtk_selection_data_set_uris (selection_data, uris);

        g_strfreev (uris);
    }
    else if (gtk_targets_include_text (&target, 1))
    {
        char *str;
        gsize len;

        str = convert_file_list_to_string (clipboard_info, TRUE, &len);
        gtk_selection_data_set_text (selection_data, str, len);
        g_free (str);
    }
    else if (target == copied_files_atom)
    {
        char *str;
        gsize len;

        str = convert_file_list_to_string (clipboard_info, FALSE, &len);
        gtk_selection_data_set (selection_data, copied_files_atom, 8, str, len);
        g_free (str);
    }
}
