path: root/e-util/e-attachment.c

/*
 * e-attachment.c
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) version 3.
 *
 * 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 the program; if not, see <http://www.gnu.org/licenses/>
 *
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 *
 */

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

#include "e-attachment.h"

#include <errno.h>
#include <glib/gi18n.h>
#include <glib/gstdio.h>

#include <libedataserver/libedataserver.h>

#include "e-attachment-store.h"
#include "e-icon-factory.h"
#include "e-mktemp.h"

#define E_ATTACHMENT_GET_PRIVATE(obj) \
    (G_TYPE_INSTANCE_GET_PRIVATE \
    ((obj), E_TYPE_ATTACHMENT, EAttachmentPrivate))

/* Fallback Icon */
#define DEFAULT_ICON_NAME   "mail-attachment"

/* Emblems */
#define EMBLEM_CANCELLED    "gtk-cancel"
#define EMBLEM_LOADING      "emblem-downloads"
#define EMBLEM_SAVING       "document-save"
#define EMBLEM_ENCRYPT_WEAK "security-low"
#define EMBLEM_ENCRYPT_STRONG   "security-high"
#define EMBLEM_ENCRYPT_UNKNOWN  "security-medium"
#define EMBLEM_SIGN_BAD     "stock_signature-bad"
#define EMBLEM_SIGN_GOOD    "stock_signature-ok"
#define EMBLEM_SIGN_UNKNOWN "stock_signature"

/* Attributes needed for EAttachmentStore columns. */
#define ATTACHMENT_QUERY "standard::*,preview::*,thumbnail::*"

struct _EAttachmentPrivate {
    GMutex property_lock;

    GFile *file;
    GIcon *icon;
    GFileInfo *file_info;
    GCancellable *cancellable;
    CamelMimePart *mime_part;
    guint emblem_timeout_id;
    gchar *disposition;
    gint percent;
    gint64 last_percent_notify; /* to avoid excessive notifications */

    guint can_show : 1;
    guint loading  : 1;
    guint saving   : 1;
    guint shown    : 1;

    camel_cipher_validity_encrypt_t encrypted;
    camel_cipher_validity_sign_t signed_;

    /* This is a reference to our row in an EAttachmentStore,
     * serving as a means of broadcasting "row-changed" signals.
     * If we are removed from the store, we lazily free the
     * reference when it is found to be to be invalid. */
    GtkTreeRowReference *reference;

    /* These are IDs for idle callbacks,
     * protected by the idle_lock mutex. */
    GMutex idle_lock;
    guint update_icon_column_idle_id;
    guint update_progress_columns_idle_id;
    guint update_file_info_columns_idle_id;
};

enum {
    PROP_0,
    PROP_CAN_SHOW,
    PROP_DISPOSITION,
    PROP_ENCRYPTED,
    PROP_FILE,
    PROP_FILE_INFO,
    PROP_ICON,
    PROP_LOADING,
    PROP_MIME_PART,
    PROP_PERCENT,
    PROP_REFERENCE,
    PROP_SAVING,
    PROP_SHOWN,
    PROP_SIGNED
};

G_DEFINE_TYPE (
    EAttachment,
    e_attachment,
    G_TYPE_OBJECT)

static gboolean
create_system_thumbnail (EAttachment *attachment,
                         GIcon **icon)
{
    GFile *file;
    GFile *icon_file;
    gchar *file_path = NULL;
    gchar *thumbnail = NULL;
    gboolean success = FALSE;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), FALSE);
    g_return_val_if_fail (icon != NULL, FALSE);

    file = e_attachment_ref_file (attachment);
    if (file != NULL)
        file_path = g_file_get_path (file);

    if (file_path != NULL) {
        thumbnail = e_icon_factory_create_thumbnail (file_path);
        g_free (file_path);
    }

    if (thumbnail == NULL)
        goto exit;

    icon_file = g_file_new_for_path (thumbnail);

    if (*icon != NULL)
        g_object_unref (*icon);

    *icon = g_file_icon_new (icon_file);

    g_object_unref (icon_file);

    if (file != NULL) {
        GFileInfo *file_info;
        const gchar *attribute;

        file_info = e_attachment_ref_file_info (attachment);
        attribute = G_FILE_ATTRIBUTE_THUMBNAIL_PATH;

        if (file_info != NULL) {
            g_file_info_set_attribute_byte_string (
                file_info, attribute, thumbnail);
            g_object_unref (file_info);
        }
    }

    g_free (thumbnail);

    success = TRUE;

exit:
    g_clear_object (&file);

    return success;
}

static gchar *
attachment_get_default_charset (void)
{
    GSettings *settings;
    gchar *charset;

    /* XXX This doesn't really belong here. */

    settings = g_settings_new ("org.gnome.evolution.mail");
    charset = g_settings_get_string (settings, "composer-charset");
    if (charset == NULL || *charset == '\0') {
        g_free (charset);
        /* FIXME This was "/apps/evolution/mail/format/charset",
         *       not sure it relates to "charset" */
        charset = g_settings_get_string (settings, "charset");
        if (charset == NULL || *charset == '\0') {
            g_free (charset);
            charset = NULL;
        }
    }
    g_object_unref (settings);

    if (charset == NULL)
        charset = g_strdup (camel_iconv_locale_charset ());

    if (charset == NULL)
        charset = g_strdup ("us-ascii");

    return charset;
}

static gboolean
attachment_update_file_info_columns_idle_cb (gpointer weak_ref)
{
    EAttachment *attachment;
    GtkTreeRowReference *reference;
    GtkTreeModel *model;
    GtkTreePath *path;
    GtkTreeIter iter;
    GFileInfo *file_info;
    const gchar *content_type;
    const gchar *display_name;
    gchar *content_desc;
    gchar *display_size;
    gchar *description;
    gchar *caption;
    goffset size;

    attachment = g_weak_ref_get (weak_ref);
    if (attachment == NULL)
        goto exit;

    g_mutex_lock (&attachment->priv->idle_lock);
    attachment->priv->update_file_info_columns_idle_id = 0;
    g_mutex_unlock (&attachment->priv->idle_lock);

    reference = e_attachment_get_reference (attachment);
    if (!gtk_tree_row_reference_valid (reference))
        goto exit;

    file_info = e_attachment_ref_file_info (attachment);
    if (file_info == NULL)
        goto exit;

    model = gtk_tree_row_reference_get_model (reference);
    path = gtk_tree_row_reference_get_path (reference);
    gtk_tree_model_get_iter (model, &iter, path);
    gtk_tree_path_free (path);

    content_type = g_file_info_get_content_type (file_info);
    display_name = g_file_info_get_display_name (file_info);
    size = g_file_info_get_size (file_info);

    content_desc = g_content_type_get_description (content_type);
    display_size = g_format_size (size);

    description = e_attachment_dup_description (attachment);
    if (description == NULL || *description == '\0') {
        g_free (description);
        description = g_strdup (display_name);
    }

    if (size > 0)
        caption = g_strdup_printf (
            "%s\n(%s)", description, display_size);
    else
        caption = g_strdup (description);

    gtk_list_store_set (
        GTK_LIST_STORE (model), &iter,
        E_ATTACHMENT_STORE_COLUMN_CAPTION, caption,
        E_ATTACHMENT_STORE_COLUMN_CONTENT_TYPE, content_desc,
        E_ATTACHMENT_STORE_COLUMN_DESCRIPTION, description,
        E_ATTACHMENT_STORE_COLUMN_SIZE, size,
        -1);

    g_free (content_desc);
    g_free (display_size);
    g_free (description);
    g_free (caption);

    g_clear_object (&file_info);

exit:
    g_clear_object (&attachment);

    return FALSE;
}

static void
attachment_update_file_info_columns (EAttachment *attachment)
{
    g_mutex_lock (&attachment->priv->idle_lock);

    if (attachment->priv->update_file_info_columns_idle_id == 0) {
        guint idle_id;

        idle_id = g_idle_add_full (
            G_PRIORITY_HIGH_IDLE,
            attachment_update_file_info_columns_idle_cb,
            e_weak_ref_new (attachment),
            (GDestroyNotify) e_weak_ref_free);
        attachment->priv->update_file_info_columns_idle_id = idle_id;
    }

    g_mutex_unlock (&attachment->priv->idle_lock);
}

static gboolean
attachment_update_icon_column_idle_cb (gpointer weak_ref)
{
    EAttachment *attachment;
    GtkTreeRowReference *reference;
    GtkTreeModel *model;
    GtkTreePath *path;
    GtkTreeIter iter;
    GFileInfo *file_info;
    GCancellable *cancellable;
    GIcon *icon = NULL;
    const gchar *emblem_name = NULL;
    const gchar *thumbnail_path = NULL;

    attachment = g_weak_ref_get (weak_ref);
    if (attachment == NULL)
        goto exit;

    g_mutex_lock (&attachment->priv->idle_lock);
    attachment->priv->update_icon_column_idle_id = 0;
    g_mutex_unlock (&attachment->priv->idle_lock);

    reference = e_attachment_get_reference (attachment);
    if (!gtk_tree_row_reference_valid (reference))
        goto exit;

    model = gtk_tree_row_reference_get_model (reference);
    path = gtk_tree_row_reference_get_path (reference);
    gtk_tree_model_get_iter (model, &iter, path);
    gtk_tree_path_free (path);

    cancellable = attachment->priv->cancellable;
    file_info = e_attachment_ref_file_info (attachment);

    if (file_info != NULL) {
        icon = g_file_info_get_icon (file_info);
        thumbnail_path = g_file_info_get_attribute_byte_string (
            file_info, G_FILE_ATTRIBUTE_THUMBNAIL_PATH);
    }

    /* Prefer the thumbnail if we have one. */
    if (thumbnail_path != NULL && *thumbnail_path != '\0') {
        GFile *file;

        file = g_file_new_for_path (thumbnail_path);
        icon = g_file_icon_new (file);
        g_object_unref (file);

    /* Try the system thumbnailer. */
    } else if (create_system_thumbnail (attachment, &icon)) {
        /* Nothing to do, just use the icon. */

    /* Else use the standard icon for the content type. */
    } else if (icon != NULL)
        g_object_ref (icon);

    /* Last ditch fallback.  (GFileInfo not yet loaded?) */
    else
        icon = g_themed_icon_new (DEFAULT_ICON_NAME);

    /* Pick an emblem, limit one.  Choices listed by priority. */

    if (g_cancellable_is_cancelled (cancellable))
        emblem_name = EMBLEM_CANCELLED;

    else if (e_attachment_get_loading (attachment))
        emblem_name = EMBLEM_LOADING;

    else if (e_attachment_get_saving (attachment))
        emblem_name = EMBLEM_SAVING;

    else if (e_attachment_get_encrypted (attachment))
        switch (e_attachment_get_encrypted (attachment)) {
            case CAMEL_CIPHER_VALIDITY_ENCRYPT_WEAK:
                emblem_name = EMBLEM_ENCRYPT_WEAK;
                break;

            case CAMEL_CIPHER_VALIDITY_ENCRYPT_ENCRYPTED:
                emblem_name = EMBLEM_ENCRYPT_UNKNOWN;
                break;

            case CAMEL_CIPHER_VALIDITY_ENCRYPT_STRONG:
                emblem_name = EMBLEM_ENCRYPT_STRONG;
                break;

            default:
                g_warn_if_reached ();
                break;
        }

    else if (e_attachment_get_signed (attachment))
        switch (e_attachment_get_signed (attachment)) {
            case CAMEL_CIPHER_VALIDITY_SIGN_GOOD:
                emblem_name = EMBLEM_SIGN_GOOD;
                break;

            case CAMEL_CIPHER_VALIDITY_SIGN_BAD:
                emblem_name = EMBLEM_SIGN_BAD;
                break;

            case CAMEL_CIPHER_VALIDITY_SIGN_UNKNOWN:
            case CAMEL_CIPHER_VALIDITY_SIGN_NEED_PUBLIC_KEY:
                emblem_name = EMBLEM_SIGN_UNKNOWN;
                break;

            default:
                g_warn_if_reached ();
                break;
        }

    if (emblem_name != NULL) {
        GIcon *emblemed_icon;
        GEmblem *emblem;

        emblemed_icon = g_themed_icon_new (emblem_name);
        emblem = g_emblem_new (emblemed_icon);
        g_object_unref (emblemed_icon);

        emblemed_icon = g_emblemed_icon_new (icon, emblem);
        g_object_unref (emblem);
        g_object_unref (icon);

        icon = emblemed_icon;
    }

    gtk_list_store_set (
        GTK_LIST_STORE (model), &iter,
        E_ATTACHMENT_STORE_COLUMN_ICON, icon,
        -1);

    /* Cache the icon to reuse for things like drag-n-drop. */
    if (attachment->priv->icon != NULL)
        g_object_unref (attachment->priv->icon);
    attachment->priv->icon = icon;
    g_object_notify (G_OBJECT (attachment), "icon");

    g_clear_object (&file_info);

exit:
    g_clear_object (&attachment);

    return FALSE;
}

static void
attachment_update_icon_column (EAttachment *attachment)
{
    g_mutex_lock (&attachment->priv->idle_lock);

    if (attachment->priv->update_icon_column_idle_id == 0) {
        guint idle_id;

        idle_id = g_idle_add_full (
            G_PRIORITY_HIGH_IDLE,
            attachment_update_icon_column_idle_cb,
            e_weak_ref_new (attachment),
            (GDestroyNotify) e_weak_ref_free);
        attachment->priv->update_icon_column_idle_id = idle_id;
    }

    g_mutex_unlock (&attachment->priv->idle_lock);
}

static gboolean
attachment_update_progress_columns_idle_cb (gpointer weak_ref)
{
    EAttachment *attachment;
    GtkTreeRowReference *reference;
    GtkTreeModel *model;
    GtkTreePath *path;
    GtkTreeIter iter;
    gboolean loading;
    gboolean saving;
    gint percent;

    attachment = g_weak_ref_get (weak_ref);
    if (attachment == NULL)
        goto exit;

    g_mutex_lock (&attachment->priv->idle_lock);
    attachment->priv->update_progress_columns_idle_id = 0;
    g_mutex_unlock (&attachment->priv->idle_lock);

    reference = e_attachment_get_reference (attachment);
    if (!gtk_tree_row_reference_valid (reference))
        goto exit;

    model = gtk_tree_row_reference_get_model (reference);
    path = gtk_tree_row_reference_get_path (reference);
    gtk_tree_model_get_iter (model, &iter, path);
    gtk_tree_path_free (path);

    /* Don't show progress bars until we have progress to report. */
    percent = e_attachment_get_percent (attachment);
    loading = e_attachment_get_loading (attachment) && (percent > 0);
    saving = e_attachment_get_saving (attachment) && (percent > 0);

    gtk_list_store_set (
        GTK_LIST_STORE (model), &iter,
        E_ATTACHMENT_STORE_COLUMN_LOADING, loading,
        E_ATTACHMENT_STORE_COLUMN_PERCENT, percent,
        E_ATTACHMENT_STORE_COLUMN_SAVING, saving,
        -1);

exit:
    g_clear_object (&attachment);

    return FALSE;
}

static void
attachment_update_progress_columns (EAttachment *attachment)
{
    g_mutex_lock (&attachment->priv->idle_lock);

    if (attachment->priv->update_progress_columns_idle_id == 0) {
        guint idle_id;

        idle_id = g_idle_add_full (
            G_PRIORITY_HIGH_IDLE,
            attachment_update_progress_columns_idle_cb,
            e_weak_ref_new (attachment),
            (GDestroyNotify) e_weak_ref_free);
        attachment->priv->update_progress_columns_idle_id = idle_id;
    }

    g_mutex_unlock (&attachment->priv->idle_lock);
}

static void
attachment_set_loading (EAttachment *attachment,
                        gboolean loading)
{
    GtkTreeRowReference *reference;

    reference = e_attachment_get_reference (attachment);

    attachment->priv->percent = 0;
    attachment->priv->loading = loading;
    attachment->priv->last_percent_notify = 0;

    g_object_freeze_notify (G_OBJECT (attachment));
    g_object_notify (G_OBJECT (attachment), "percent");
    g_object_notify (G_OBJECT (attachment), "loading");
    g_object_thaw_notify (G_OBJECT (attachment));

    if (gtk_tree_row_reference_valid (reference)) {
        GtkTreeModel *model;
        model = gtk_tree_row_reference_get_model (reference);
        g_object_notify (G_OBJECT (model), "num-loading");
    }
}

static void
attachment_set_saving (EAttachment *attachment,
                       gboolean saving)
{
    attachment->priv->percent = 0;
    attachment->priv->saving = saving;
    attachment->priv->last_percent_notify = 0;

    /* g_object_freeze_notify (G_OBJECT (attachment));
    g_object_notify (G_OBJECT (attachment), "percent");
    g_object_notify (G_OBJECT (attachment), "saving");
    g_object_thaw_notify (G_OBJECT (attachment)); */
}

static void
attachment_progress_cb (goffset current_num_bytes,
                        goffset total_num_bytes,
                        EAttachment *attachment)
{
    gint new_percent;

    /* Avoid dividing by zero. */
    if (total_num_bytes == 0)
        return;

    /* do not notify too often, 5 times per second is sufficient */
    if (g_get_monotonic_time () - attachment->priv->last_percent_notify < 200000)
        return;

    attachment->priv->last_percent_notify = g_get_monotonic_time ();

    new_percent = (current_num_bytes * 100) / total_num_bytes;

    if (new_percent != attachment->priv->percent) {
        attachment->priv->percent = new_percent;
        /* g_object_notify (G_OBJECT (attachment), "percent"); */
    }
}

static gboolean
attachment_cancelled_timeout_cb (EAttachment *attachment)
{
    attachment->priv->emblem_timeout_id = 0;
    g_cancellable_reset (attachment->priv->cancellable);

    attachment_update_icon_column (attachment);

    return FALSE;
}

static void
attachment_cancelled_cb (EAttachment *attachment)
{
    /* Reset the GCancellable after one second.  This causes a
     * cancel emblem to be briefly shown on the attachment icon
     * as visual feedback that an operation was cancelled. */

    if (attachment->priv->emblem_timeout_id > 0)
        g_source_remove (attachment->priv->emblem_timeout_id);

    attachment->priv->emblem_timeout_id = g_timeout_add_seconds (
        1, (GSourceFunc) attachment_cancelled_timeout_cb, attachment);

    attachment_update_icon_column (attachment);
}

static void
attachment_set_property (GObject *object,
                         guint property_id,
                         const GValue *value,
                         GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_CAN_SHOW:
            e_attachment_set_can_show (
                E_ATTACHMENT (object),
                g_value_get_boolean (value));
            return;

        case PROP_DISPOSITION:
            e_attachment_set_disposition (
                E_ATTACHMENT (object),
                g_value_get_string (value));
            return;

        case PROP_ENCRYPTED:
            e_attachment_set_encrypted (
                E_ATTACHMENT (object),
                g_value_get_int (value));
            return;

        case PROP_FILE:
            e_attachment_set_file (
                E_ATTACHMENT (object),
                g_value_get_object (value));
            return;

        case PROP_SHOWN:
            e_attachment_set_shown (
                E_ATTACHMENT (object),
                g_value_get_boolean (value));
            return;

        case PROP_MIME_PART:
            e_attachment_set_mime_part (
                E_ATTACHMENT (object),
                g_value_get_object (value));
            return;

        case PROP_REFERENCE:
            e_attachment_set_reference (
                E_ATTACHMENT (object),
                g_value_get_boxed (value));
            return;

        case PROP_SIGNED:
            e_attachment_set_signed (
                E_ATTACHMENT (object),
                g_value_get_int (value));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
attachment_get_property (GObject *object,
                         guint property_id,
                         GValue *value,
                         GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_CAN_SHOW:
            g_value_set_boolean (
                value,
                e_attachment_get_can_show (
                E_ATTACHMENT (object)));
            return;

        case PROP_DISPOSITION:
            g_value_set_string (
                value,
                e_attachment_get_disposition (
                E_ATTACHMENT (object)));
            return;

        case PROP_ENCRYPTED:
            g_value_set_int (
                value,
                e_attachment_get_encrypted (
                E_ATTACHMENT (object)));
            return;

        case PROP_FILE:
            g_value_take_object (
                value,
                e_attachment_ref_file (
                E_ATTACHMENT (object)));
            return;

        case PROP_FILE_INFO:
            g_value_take_object (
                value,
                e_attachment_ref_file_info (
                E_ATTACHMENT (object)));
            return;

        case PROP_ICON:
            g_value_take_object (
                value,
                e_attachment_ref_icon (
                E_ATTACHMENT (object)));
            return;

        case PROP_SHOWN:
            g_value_set_boolean (
                value,
                e_attachment_get_shown (
                E_ATTACHMENT (object)));
            return;

        case PROP_LOADING:
            g_value_set_boolean (
                value,
                e_attachment_get_loading (
                E_ATTACHMENT (object)));
            return;

        case PROP_MIME_PART:
            g_value_take_object (
                value,
                e_attachment_ref_mime_part (
                E_ATTACHMENT (object)));
            return;

        case PROP_PERCENT:
            g_value_set_int (
                value,
                e_attachment_get_percent (
                E_ATTACHMENT (object)));
            return;

        case PROP_REFERENCE:
            g_value_set_boxed (
                value,
                e_attachment_get_reference (
                E_ATTACHMENT (object)));
            return;

        case PROP_SAVING:
            g_value_set_boolean (
                value,
                e_attachment_get_saving (
                E_ATTACHMENT (object)));
            return;

        case PROP_SIGNED:
            g_value_set_int (
                value,
                e_attachment_get_signed (
                E_ATTACHMENT (object)));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
attachment_dispose (GObject *object)
{
    EAttachmentPrivate *priv;

    priv = E_ATTACHMENT_GET_PRIVATE (object);

    g_clear_object (&priv->file);
    g_clear_object (&priv->icon);
    g_clear_object (&priv->file_info);
    g_clear_object (&priv->cancellable);
    g_clear_object (&priv->mime_part);

    if (priv->emblem_timeout_id > 0) {
        g_source_remove (priv->emblem_timeout_id);
        priv->emblem_timeout_id = 0;
    }

    /* This accepts NULL arguments. */
    gtk_tree_row_reference_free (priv->reference);
    priv->reference = NULL;

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

static void
attachment_finalize (GObject *object)
{
    EAttachmentPrivate *priv;

    priv = E_ATTACHMENT_GET_PRIVATE (object);

    if (priv->update_icon_column_idle_id > 0)
        g_source_remove (priv->update_icon_column_idle_id);

    if (priv->update_progress_columns_idle_id > 0)
        g_source_remove (priv->update_progress_columns_idle_id);

    if (priv->update_file_info_columns_idle_id > 0)
        g_source_remove (priv->update_file_info_columns_idle_id);

    g_mutex_clear (&priv->property_lock);
    g_mutex_clear (&priv->idle_lock);

    g_free (priv->disposition);

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

static void
e_attachment_class_init (EAttachmentClass *class)
{
    GObjectClass *object_class;

    g_type_class_add_private (class, sizeof (EAttachmentPrivate));

    object_class = G_OBJECT_CLASS (class);
    object_class->set_property = attachment_set_property;
    object_class->get_property = attachment_get_property;
    object_class->dispose = attachment_dispose;
    object_class->finalize = attachment_finalize;

    g_object_class_install_property (
        object_class,
        PROP_CAN_SHOW,
        g_param_spec_boolean (
            "can-show",
            "Can Show",
            NULL,
            FALSE,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT));

    g_object_class_install_property (
        object_class,
        PROP_DISPOSITION,
        g_param_spec_string (
            "disposition",
            "Disposition",
            NULL,
            "attachment",
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT));

    /* FIXME Define a GEnumClass for this. */
    g_object_class_install_property (
        object_class,
        PROP_ENCRYPTED,
        g_param_spec_int (
            "encrypted",
            "Encrypted",
            NULL,
            CAMEL_CIPHER_VALIDITY_ENCRYPT_NONE,
            CAMEL_CIPHER_VALIDITY_ENCRYPT_STRONG,
            CAMEL_CIPHER_VALIDITY_ENCRYPT_NONE,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT));

    g_object_class_install_property (
        object_class,
        PROP_FILE,
        g_param_spec_object (
            "file",
            "File",
            NULL,
            G_TYPE_FILE,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT));

    g_object_class_install_property (
        object_class,
        PROP_FILE_INFO,
        g_param_spec_object (
            "file-info",
            "File Info",
            NULL,
            G_TYPE_FILE_INFO,
            G_PARAM_READABLE));

    g_object_class_install_property (
        object_class,
        PROP_ICON,
        g_param_spec_object (
            "icon",
            "Icon",
            NULL,
            G_TYPE_ICON,
            G_PARAM_READABLE));

    g_object_class_install_property (
        object_class,
        PROP_LOADING,
        g_param_spec_boolean (
            "loading",
            "Loading",
            NULL,
            FALSE,
            G_PARAM_READABLE));

    g_object_class_install_property (
        object_class,
        PROP_MIME_PART,
        g_param_spec_object (
            "mime-part",
            "MIME Part",
            NULL,
            CAMEL_TYPE_MIME_PART,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_PERCENT,
        g_param_spec_int (
            "percent",
            "Percent",
            NULL,
            0,
            100,
            0,
            G_PARAM_READABLE));

    g_object_class_install_property (
        object_class,
        PROP_REFERENCE,
        g_param_spec_boxed (
            "reference",
            "Reference",
            NULL,
            GTK_TYPE_TREE_ROW_REFERENCE,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_SAVING,
        g_param_spec_boolean (
            "saving",
            "Saving",
            NULL,
            FALSE,
            G_PARAM_READABLE));

    g_object_class_install_property (
        object_class,
        PROP_SHOWN,
        g_param_spec_boolean (
            "shown",
            "Shown",
            NULL,
            FALSE,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT));

    /* FIXME Define a GEnumClass for this. */
    g_object_class_install_property (
        object_class,
        PROP_SIGNED,
        g_param_spec_int (
            "signed",
            "Signed",
            NULL,
            CAMEL_CIPHER_VALIDITY_SIGN_NONE,
            CAMEL_CIPHER_VALIDITY_SIGN_NEED_PUBLIC_KEY,
            CAMEL_CIPHER_VALIDITY_SIGN_NONE,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT));
}

static void
e_attachment_init (EAttachment *attachment)
{
    attachment->priv = E_ATTACHMENT_GET_PRIVATE (attachment);
    attachment->priv->cancellable = g_cancellable_new ();
    attachment->priv->encrypted = CAMEL_CIPHER_VALIDITY_ENCRYPT_NONE;
    attachment->priv->signed_ = CAMEL_CIPHER_VALIDITY_SIGN_NONE;

    g_mutex_init (&attachment->priv->property_lock);
    g_mutex_init (&attachment->priv->idle_lock);

    g_signal_connect (
        attachment, "notify::encrypted",
        G_CALLBACK (attachment_update_icon_column), NULL);

    g_signal_connect (
        attachment, "notify::file-info",
        G_CALLBACK (attachment_update_file_info_columns), NULL);

    g_signal_connect (
        attachment, "notify::file-info",
        G_CALLBACK (attachment_update_icon_column), NULL);

    g_signal_connect (
        attachment, "notify::loading",
        G_CALLBACK (attachment_update_icon_column), NULL);

    g_signal_connect (
        attachment, "notify::loading",
        G_CALLBACK (attachment_update_progress_columns), NULL);

    g_signal_connect (
        attachment, "notify::percent",
        G_CALLBACK (attachment_update_progress_columns), NULL);

    g_signal_connect (
        attachment, "notify::reference",
        G_CALLBACK (attachment_update_file_info_columns), NULL);

    g_signal_connect (
        attachment, "notify::reference",
        G_CALLBACK (attachment_update_icon_column), NULL);

    g_signal_connect (
        attachment, "notify::reference",
        G_CALLBACK (attachment_update_progress_columns), NULL);

    g_signal_connect (
        attachment, "notify::saving",
        G_CALLBACK (attachment_update_icon_column), NULL);

    g_signal_connect (
        attachment, "notify::saving",
        G_CALLBACK (attachment_update_progress_columns), NULL);

    g_signal_connect (
        attachment, "notify::signed",
        G_CALLBACK (attachment_update_icon_column), NULL);

    g_signal_connect_swapped (
        attachment->priv->cancellable, "cancelled",
        G_CALLBACK (attachment_cancelled_cb), attachment);
}

EAttachment *
e_attachment_new (void)
{
    return g_object_new (E_TYPE_ATTACHMENT, NULL);
}

EAttachment *
e_attachment_new_for_path (const gchar *path)
{
    EAttachment *attachment;
    GFile *file;

    g_return_val_if_fail (path != NULL, NULL);

    file = g_file_new_for_path (path);
    attachment = g_object_new (E_TYPE_ATTACHMENT, "file", file, NULL);
    g_object_unref (file);

    return attachment;
}

EAttachment *
e_attachment_new_for_uri (const gchar *uri)
{
    EAttachment *attachment;
    GFile *file;

    g_return_val_if_fail (uri != NULL, NULL);

    file = g_file_new_for_uri (uri);
    attachment = g_object_new (E_TYPE_ATTACHMENT, "file", file, NULL);
    g_object_unref (file);

    return attachment;
}

EAttachment *
e_attachment_new_for_message (CamelMimeMessage *message)
{
    CamelDataWrapper *wrapper;
    CamelMimePart *mime_part;
    EAttachment *attachment;
    GString *description;
    const gchar *subject;

    g_return_val_if_fail (CAMEL_IS_MIME_MESSAGE (message), NULL);

    mime_part = camel_mime_part_new ();
    camel_mime_part_set_disposition (mime_part, "inline");
    subject = camel_mime_message_get_subject (message);

    /* To Translators: This text is set as a description of an attached
     * message when, for example, attaching it to a composer. When the
     * message to be attached has also filled Subject, then this text is
     * of form "Attached message - Subject", otherwise it's left as is. */
    description = g_string_new (_("Attached message"));
    if (subject != NULL)
        g_string_append_printf (description, " - %s", subject);
    camel_mime_part_set_description (mime_part, description->str);
    g_string_free (description, TRUE);

    wrapper = CAMEL_DATA_WRAPPER (message);
    camel_medium_set_content (CAMEL_MEDIUM (mime_part), wrapper);
    camel_mime_part_set_content_type (mime_part, "message/rfc822");

    attachment = e_attachment_new ();
    e_attachment_set_mime_part (attachment, mime_part);
    g_object_unref (mime_part);

    return attachment;
}

void
e_attachment_add_to_multipart (EAttachment *attachment,
                               CamelMultipart *multipart,
                               const gchar *default_charset)
{
    CamelContentType *content_type;
    CamelDataWrapper *wrapper;
    CamelMimePart *mime_part;

    /* XXX EMsgComposer might be a better place for this function. */

    g_return_if_fail (E_IS_ATTACHMENT (attachment));
    g_return_if_fail (CAMEL_IS_MULTIPART (multipart));

    /* Still loading?  Too bad. */
    mime_part = e_attachment_ref_mime_part (attachment);
    if (mime_part == NULL)
        return;

    content_type = camel_mime_part_get_content_type (mime_part);
    wrapper = camel_medium_get_content (CAMEL_MEDIUM (mime_part));

    if (CAMEL_IS_MULTIPART (wrapper))
        goto exit;

    /* For text content, determine the best encoding and character set. */
    if (camel_content_type_is (content_type, "text", "*")) {
        CamelTransferEncoding encoding;
        CamelStream *filtered_stream;
        CamelMimeFilter *filter;
        CamelStream *stream;
        const gchar *charset;

        charset = camel_content_type_param (content_type, "charset");

        /* Determine the best encoding by writing the MIME
         * part to a NULL stream with a "bestenc" filter. */
        stream = camel_stream_null_new ();
        filtered_stream = camel_stream_filter_new (stream);
        filter = camel_mime_filter_bestenc_new (
            CAMEL_BESTENC_GET_ENCODING);
        camel_stream_filter_add (
            CAMEL_STREAM_FILTER (filtered_stream),
            CAMEL_MIME_FILTER (filter));
        camel_data_wrapper_decode_to_stream_sync (
            wrapper, filtered_stream, NULL, NULL);
        g_object_unref (filtered_stream);
        g_object_unref (stream);

        /* Retrieve the best encoding from the filter. */
        encoding = camel_mime_filter_bestenc_get_best_encoding (
            CAMEL_MIME_FILTER_BESTENC (filter),
            CAMEL_BESTENC_8BIT);
        camel_mime_part_set_encoding (mime_part, encoding);
        g_object_unref (filter);

        if (encoding == CAMEL_TRANSFER_ENCODING_7BIT) {
            /* The text fits within us-ascii, so this is safe.
             * FIXME Check that this isn't iso-2022-jp? */
            default_charset = "us-ascii";

        } else if (charset == NULL && default_charset == NULL) {
            default_charset = attachment_get_default_charset ();
            /* FIXME Check that this fits within the
             *       default_charset and if not, find one
             *       that does and/or allow the user to
             *       specify. */
        }

        if (charset == NULL) {
            gchar *type;

            camel_content_type_set_param (
                content_type, "charset", default_charset);
            type = camel_content_type_format (content_type);
            camel_mime_part_set_content_type (mime_part, type);
            g_free (type);
        }

    /* Otherwise, unless it's a message/rfc822, Base64 encode it. */
    } else if (!CAMEL_IS_MIME_MESSAGE (wrapper))
        camel_mime_part_set_encoding (
            mime_part, CAMEL_TRANSFER_ENCODING_BASE64);

exit:
    camel_multipart_add_part (multipart, mime_part);

    g_clear_object (&mime_part);
}

void
e_attachment_cancel (EAttachment *attachment)
{
    g_return_if_fail (E_IS_ATTACHMENT (attachment));

    g_cancellable_cancel (attachment->priv->cancellable);
}

gboolean
e_attachment_get_can_show (EAttachment *attachment)
{
    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), FALSE);

    return attachment->priv->can_show;
}

void
e_attachment_set_can_show (EAttachment *attachment,
                           gboolean can_show)
{
    g_return_if_fail (E_IS_ATTACHMENT (attachment));

    attachment->priv->can_show = can_show;

    g_object_notify (G_OBJECT (attachment), "can-show");
}

const gchar *
e_attachment_get_disposition (EAttachment *attachment)
{
    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), NULL);

    return attachment->priv->disposition;
}

gchar *
e_attachment_dup_disposition (EAttachment *attachment)
{
    const gchar *protected;
    gchar *duplicate;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), NULL);

    g_mutex_lock (&attachment->priv->property_lock);

    protected = e_attachment_get_disposition (attachment);
    duplicate = g_strdup (protected);

    g_mutex_unlock (&attachment->priv->property_lock);

    return duplicate;
}

void
e_attachment_set_disposition (EAttachment *attachment,
                              const gchar *disposition)
{
    g_return_if_fail (E_IS_ATTACHMENT (attachment));

    g_mutex_lock (&attachment->priv->property_lock);

    g_free (attachment->priv->disposition);
    attachment->priv->disposition = g_strdup (disposition);

    g_mutex_unlock (&attachment->priv->property_lock);

    g_object_notify (G_OBJECT (attachment), "disposition");
}

GFile *
e_attachment_ref_file (EAttachment *attachment)
{
    GFile *file = NULL;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), NULL);

    g_mutex_lock (&attachment->priv->property_lock);

    if (attachment->priv->file != NULL)
        file = g_object_ref (attachment->priv->file);

    g_mutex_unlock (&attachment->priv->property_lock);

    return file;
}

void
e_attachment_set_file (EAttachment *attachment,
                       GFile *file)
{
    g_return_if_fail (E_IS_ATTACHMENT (attachment));

    if (file != NULL) {
        g_return_if_fail (G_IS_FILE (file));
        g_object_ref (file);
    }

    g_mutex_lock (&attachment->priv->property_lock);

    g_clear_object (&attachment->priv->file);
    attachment->priv->file = file;

    g_mutex_unlock (&attachment->priv->property_lock);

    g_object_notify (G_OBJECT (attachment), "file");
}

GFileInfo *
e_attachment_ref_file_info (EAttachment *attachment)
{
    GFileInfo *file_info = NULL;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), NULL);

    g_mutex_lock (&attachment->priv->property_lock);

    if (attachment->priv->file_info != NULL)
        file_info = g_object_ref (attachment->priv->file_info);

    g_mutex_unlock (&attachment->priv->property_lock);

    return file_info;
}

void
e_attachment_set_file_info (EAttachment *attachment,
                            GFileInfo *file_info)
{
    GtkTreeRowReference *reference;
    GIcon *icon;

    reference = e_attachment_get_reference (attachment);

    if (file_info != NULL)
        g_object_ref (file_info);

    if (attachment->priv->file_info != NULL)
        g_object_unref (attachment->priv->file_info);

    attachment->priv->file_info = file_info;

    /* If the GFileInfo contains a GThemedIcon, append a
     * fallback icon name to ensure we display something. */
    icon = g_file_info_get_icon (file_info);
    if (G_IS_THEMED_ICON (icon))
        g_themed_icon_append_name (
            G_THEMED_ICON (icon), DEFAULT_ICON_NAME);

    g_object_notify (G_OBJECT (attachment), "file-info");

    /* Tell the EAttachmentStore its total size changed. */
    if (gtk_tree_row_reference_valid (reference)) {
        GtkTreeModel *model;
        model = gtk_tree_row_reference_get_model (reference);
        g_object_notify (G_OBJECT (model), "total-size");
    }
}

/**
 * e_attachment_dup_mime_type:
 * @attachment: an #EAttachment
 *
 * Returns the MIME type of @attachment according to its #GFileInfo.
 * If the @attachment has no #GFileInfo then the function returns %NULL.
 * Free the returned MIME type string with g_free().
 *
 * Returns: a newly-allocated MIME type string, or %NULL
 **/
gchar *
e_attachment_dup_mime_type (EAttachment *attachment)
{
    GFileInfo *file_info;
    const gchar *content_type = NULL;
    gchar *mime_type = NULL;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), NULL);

    file_info = e_attachment_ref_file_info (attachment);
    if (file_info != NULL)
        content_type = g_file_info_get_content_type (file_info);

    if (content_type != NULL)
        mime_type = g_content_type_get_mime_type (content_type);

    if (mime_type != NULL)
        camel_strdown (mime_type);

    g_clear_object (&file_info);

    return mime_type;
}

GIcon *
e_attachment_ref_icon (EAttachment *attachment)
{
    GIcon *icon = NULL;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), NULL);

    g_mutex_lock (&attachment->priv->property_lock);

    if (attachment->priv->icon != NULL)
        icon = g_object_ref (attachment->priv->icon);

    g_mutex_unlock (&attachment->priv->property_lock);

    return icon;
}

gboolean
e_attachment_get_loading (EAttachment *attachment)
{
    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), FALSE);

    return attachment->priv->loading;
}

CamelMimePart *
e_attachment_ref_mime_part (EAttachment *attachment)
{
    CamelMimePart *mime_part = NULL;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), NULL);

    g_mutex_lock (&attachment->priv->property_lock);

    if (attachment->priv->mime_part != NULL)
        mime_part = g_object_ref (attachment->priv->mime_part);

    g_mutex_unlock (&attachment->priv->property_lock);

    return mime_part;
}

void
e_attachment_set_mime_part (EAttachment *attachment,
                            CamelMimePart *mime_part)
{
    g_return_if_fail (E_IS_ATTACHMENT (attachment));

    if (mime_part != NULL) {
        g_return_if_fail (CAMEL_IS_MIME_PART (mime_part));
        g_object_ref (mime_part);
    }

    g_mutex_lock (&attachment->priv->property_lock);

    g_clear_object (&attachment->priv->mime_part);
    attachment->priv->mime_part = mime_part;

    g_mutex_unlock (&attachment->priv->property_lock);

    g_object_notify (G_OBJECT (attachment), "mime-part");
}

gint
e_attachment_get_percent (EAttachment *attachment)
{
    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), 0);

    return attachment->priv->percent;
}

GtkTreeRowReference *
e_attachment_get_reference (EAttachment *attachment)
{
    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), NULL);

    return attachment->priv->reference;
}

void
e_attachment_set_reference (EAttachment *attachment,
                            GtkTreeRowReference *reference)
{
    g_return_if_fail (E_IS_ATTACHMENT (attachment));

    if (reference != NULL)
        reference = gtk_tree_row_reference_copy (reference);

    gtk_tree_row_reference_free (attachment->priv->reference);
    attachment->priv->reference = reference;

    g_object_notify (G_OBJECT (attachment), "reference");
}

gboolean
e_attachment_get_saving (EAttachment *attachment)
{
    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), FALSE);

    return attachment->priv->saving;
}

gboolean
e_attachment_get_shown (EAttachment *attachment)
{
    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), FALSE);

    return attachment->priv->shown;
}

void
e_attachment_set_shown (EAttachment *attachment,
                        gboolean shown)
{
    g_return_if_fail (E_IS_ATTACHMENT (attachment));

    attachment->priv->shown = shown;

    g_object_notify (G_OBJECT (attachment), "shown");
}

camel_cipher_validity_encrypt_t
e_attachment_get_encrypted (EAttachment *attachment)
{
    g_return_val_if_fail (
        E_IS_ATTACHMENT (attachment),
        CAMEL_CIPHER_VALIDITY_ENCRYPT_NONE);

    return attachment->priv->encrypted;
}

void
e_attachment_set_encrypted (EAttachment *attachment,
                            camel_cipher_validity_encrypt_t encrypted)
{
    g_return_if_fail (E_IS_ATTACHMENT (attachment));

    attachment->priv->encrypted = encrypted;

    g_object_notify (G_OBJECT (attachment), "encrypted");
}

camel_cipher_validity_sign_t
e_attachment_get_signed (EAttachment *attachment)
{
    g_return_val_if_fail (
        E_IS_ATTACHMENT (attachment),
        CAMEL_CIPHER_VALIDITY_SIGN_NONE);

    return attachment->priv->signed_;
}

void
e_attachment_set_signed (EAttachment *attachment,
                         camel_cipher_validity_sign_t signed_)
{
    g_return_if_fail (E_IS_ATTACHMENT (attachment));

    attachment->priv->signed_ = signed_;

    g_object_notify (G_OBJECT (attachment), "signed");
}

gchar *
e_attachment_dup_description (EAttachment *attachment)
{
    GFileInfo *file_info;
    const gchar *attribute;
    const gchar *protected;
    gchar *duplicate;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), NULL);

    file_info = e_attachment_ref_file_info (attachment);
    if (file_info == NULL)
        return NULL;

    attribute = G_FILE_ATTRIBUTE_STANDARD_DESCRIPTION;
    protected = g_file_info_get_attribute_string (file_info, attribute);
    duplicate = g_strdup (protected);

    g_object_unref (file_info);

    return duplicate;
}

gchar *
e_attachment_dup_thumbnail_path (EAttachment *attachment)
{
    GFileInfo *file_info;
    const gchar *attribute;
    const gchar *protected;
    gchar *duplicate;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), NULL);

    file_info = e_attachment_ref_file_info (attachment);
    if (file_info == NULL)
        return NULL;

    attribute = G_FILE_ATTRIBUTE_THUMBNAIL_PATH;
    protected = g_file_info_get_attribute_string (file_info, attribute);
    duplicate = g_strdup (protected);

    g_object_unref (file_info);

    return duplicate;
}

gboolean
e_attachment_is_rfc822 (EAttachment *attachment)
{
    gchar *mime_type;
    gboolean is_rfc822;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), FALSE);

    mime_type = e_attachment_dup_mime_type (attachment);
    is_rfc822 =
        (mime_type != NULL) &&
        (g_ascii_strcasecmp (mime_type, "message/rfc822") == 0);
    g_free (mime_type);

    return is_rfc822;
}

GList *
e_attachment_list_apps (EAttachment *attachment)
{
    GList *app_info_list;
    GList *guessed_infos;
    GFileInfo *file_info;
    const gchar *content_type;
    const gchar *display_name;
    gboolean type_is_unknown;
    gchar *allocated;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), NULL);

    file_info = e_attachment_ref_file_info (attachment);
    if (file_info == NULL)
        return NULL;

    content_type = g_file_info_get_content_type (file_info);
    display_name = g_file_info_get_display_name (file_info);
    g_return_val_if_fail (content_type != NULL, NULL);

    app_info_list = g_app_info_get_all_for_type (content_type);
    type_is_unknown = g_content_type_is_unknown (content_type);

    if (app_info_list != NULL && !type_is_unknown)
        goto exit;

    if (display_name == NULL)
        goto exit;

    allocated = g_content_type_guess (display_name, NULL, 0, NULL);
    guessed_infos = g_app_info_get_all_for_type (allocated);
    app_info_list = g_list_concat (guessed_infos, app_info_list);
    g_free (allocated);

exit:
    g_clear_object (&file_info);

    return app_info_list;
}

/************************* e_attachment_load_async() *************************/

typedef struct _LoadContext LoadContext;

struct _LoadContext {
    EAttachment *attachment;
    CamelMimePart *mime_part;
    GSimpleAsyncResult *simple;

    GInputStream *input_stream;
    GOutputStream *output_stream;
    GFileInfo *file_info;
    goffset total_num_bytes;
    gssize bytes_read;
    gchar buffer[4096];
};

/* Forward Declaration */
static void
attachment_load_stream_read_cb (GInputStream *input_stream,
                                GAsyncResult *result,
                                LoadContext *load_context);

static LoadContext *
attachment_load_context_new (EAttachment *attachment,
                             GAsyncReadyCallback callback,
                             gpointer user_data)
{
    LoadContext *load_context;
    GSimpleAsyncResult *simple;

    simple = g_simple_async_result_new (
        G_OBJECT (attachment), callback,
        user_data, e_attachment_load_async);

    load_context = g_slice_new0 (LoadContext);
    load_context->attachment = g_object_ref (attachment);
    load_context->simple = simple;

    attachment_set_loading (load_context->attachment, TRUE);

    return load_context;
}

static void
attachment_load_context_free (LoadContext *load_context)
{
    g_object_unref (load_context->attachment);

    if (load_context->mime_part != NULL)
        g_object_unref (load_context->mime_part);

    if (load_context->simple)
        g_object_unref (load_context->simple);

    if (load_context->input_stream != NULL)
        g_object_unref (load_context->input_stream);

    if (load_context->output_stream != NULL)
        g_object_unref (load_context->output_stream);

    if (load_context->file_info != NULL)
        g_object_unref (load_context->file_info);

    g_slice_free (LoadContext, load_context);
}

static gboolean
attachment_load_check_for_error (LoadContext *load_context,
                                 GError *error)
{
    GSimpleAsyncResult *simple;

    if (error == NULL)
        return FALSE;

    simple = load_context->simple;
    g_simple_async_result_take_error (simple, error);
    g_simple_async_result_complete (simple);

    attachment_load_context_free (load_context);

    return TRUE;
}

static void
attachment_load_finish (LoadContext *load_context)
{
    GFileInfo *file_info;
    EAttachment *attachment;
    GMemoryOutputStream *output_stream;
    GSimpleAsyncResult *simple;
    CamelDataWrapper *wrapper;
    CamelMimePart *mime_part;
    CamelStream *stream;
    const gchar *attribute;
    const gchar *content_type;
    const gchar *display_name;
    const gchar *description;
    const gchar *disposition;
    gchar *mime_type;
    gpointer data;
    gsize size;

    simple = load_context->simple;

    file_info = load_context->file_info;
    attachment = load_context->attachment;
    output_stream = G_MEMORY_OUTPUT_STREAM (load_context->output_stream);

    if (e_attachment_is_rfc822 (attachment))
        wrapper = (CamelDataWrapper *) camel_mime_message_new ();
    else
        wrapper = camel_data_wrapper_new ();

    content_type = g_file_info_get_content_type (file_info);
    mime_type = g_content_type_get_mime_type (content_type);

    data = g_memory_output_stream_get_data (output_stream);
    size = g_memory_output_stream_get_data_size (output_stream);

    stream = camel_stream_mem_new_with_buffer (data, size);
    camel_data_wrapper_construct_from_stream_sync (
        wrapper, stream, NULL, NULL);
    camel_data_wrapper_set_mime_type (wrapper, mime_type);
    camel_stream_close (stream, NULL, NULL);
    g_object_unref (stream);

    mime_part = camel_mime_part_new ();
    camel_medium_set_content (CAMEL_MEDIUM (mime_part), wrapper);

    g_object_unref (wrapper);
    g_free (mime_type);

    display_name = g_file_info_get_display_name (file_info);
    if (display_name != NULL)
        camel_mime_part_set_filename (mime_part, display_name);

    attribute = G_FILE_ATTRIBUTE_STANDARD_DESCRIPTION;
    description = g_file_info_get_attribute_string (file_info, attribute);
    if (description != NULL)
        camel_mime_part_set_description (mime_part, description);

    disposition = e_attachment_get_disposition (attachment);
    if (disposition != NULL)
        camel_mime_part_set_disposition (mime_part, disposition);

    /* Correctly report the size of zero length special files. */
    if (g_file_info_get_size (file_info) == 0)
        g_file_info_set_size (file_info, size);

    load_context->mime_part = mime_part;

    g_simple_async_result_set_op_res_gpointer (
        simple, load_context, (GDestroyNotify) attachment_load_context_free);

    g_simple_async_result_complete (simple);

    /* make sure it's freed on operation end */
    load_context->simple = NULL;
    g_object_unref (simple);
}

static void
attachment_load_write_cb (GOutputStream *output_stream,
                          GAsyncResult *result,
                          LoadContext *load_context)
{
    EAttachment *attachment;
    GCancellable *cancellable;
    GInputStream *input_stream;
    gssize bytes_written;
    GError *error = NULL;

    bytes_written = g_output_stream_write_finish (
        output_stream, result, &error);

    if (attachment_load_check_for_error (load_context, error))
        return;

    attachment = load_context->attachment;
    cancellable = attachment->priv->cancellable;
    input_stream = load_context->input_stream;

    attachment_progress_cb (
        g_seekable_tell (G_SEEKABLE (output_stream)),
        load_context->total_num_bytes, attachment);

    if (bytes_written < load_context->bytes_read) {
        g_memmove (
            load_context->buffer,
            load_context->buffer + bytes_written,
            load_context->bytes_read - bytes_written);
        load_context->bytes_read -= bytes_written;

        g_output_stream_write_async (
            output_stream,
            load_context->buffer,
            load_context->bytes_read,
            G_PRIORITY_DEFAULT, cancellable,
            (GAsyncReadyCallback) attachment_load_write_cb,
            load_context);
    } else
        g_input_stream_read_async (
            input_stream,
            load_context->buffer,
            sizeof (load_context->buffer),
            G_PRIORITY_DEFAULT, cancellable,
            (GAsyncReadyCallback) attachment_load_stream_read_cb,
            load_context);
}

static void
attachment_load_stream_read_cb (GInputStream *input_stream,
                                GAsyncResult *result,
                                LoadContext *load_context)
{
    EAttachment *attachment;
    GCancellable *cancellable;
    GOutputStream *output_stream;
    gssize bytes_read;
    GError *error = NULL;

    bytes_read = g_input_stream_read_finish (
        input_stream, result, &error);

    if (attachment_load_check_for_error (load_context, error))
        return;

    if (bytes_read == 0) {
        attachment_load_finish (load_context);
        return;
    }

    attachment = load_context->attachment;
    cancellable = attachment->priv->cancellable;
    output_stream = load_context->output_stream;
    load_context->bytes_read = bytes_read;

    g_output_stream_write_async (
        output_stream,
        load_context->buffer,
        load_context->bytes_read,
        G_PRIORITY_DEFAULT, cancellable,
        (GAsyncReadyCallback) attachment_load_write_cb,
        load_context);
}

static void
attachment_load_file_read_cb (GFile *file,
                              GAsyncResult *result,
                              LoadContext *load_context)
{
    EAttachment *attachment;
    GCancellable *cancellable;
    GFileInputStream *input_stream;
    GOutputStream *output_stream;
    GError *error = NULL;

    /* Input stream might be NULL, so don't use cast macro. */
    input_stream = g_file_read_finish (file, result, &error);
    load_context->input_stream = (GInputStream *) input_stream;

    if (attachment_load_check_for_error (load_context, error))
        return;

    /* Load the contents into a GMemoryOutputStream. */
    output_stream = g_memory_output_stream_new (
        NULL, 0, g_realloc, g_free);

    attachment = load_context->attachment;
    cancellable = attachment->priv->cancellable;
    load_context->output_stream = output_stream;

    g_input_stream_read_async (
        load_context->input_stream,
        load_context->buffer,
        sizeof (load_context->buffer),
        G_PRIORITY_DEFAULT, cancellable,
        (GAsyncReadyCallback) attachment_load_stream_read_cb,
        load_context);
}

static void
attachment_load_query_info_cb (GFile *file,
                               GAsyncResult *result,
                               LoadContext *load_context)
{
    EAttachment *attachment;
    GCancellable *cancellable;
    GFileInfo *file_info;
    GError *error = NULL;

    attachment = load_context->attachment;
    cancellable = attachment->priv->cancellable;

    file_info = g_file_query_info_finish (file, result, &error);
    if (attachment_load_check_for_error (load_context, error))
        return;

    e_attachment_set_file_info (attachment, file_info);
    load_context->file_info = file_info;

    load_context->total_num_bytes = g_file_info_get_size (file_info);

    g_file_read_async (
        file, G_PRIORITY_DEFAULT,
        cancellable, (GAsyncReadyCallback)
        attachment_load_file_read_cb, load_context);
}

#define ATTACHMENT_LOAD_CONTEXT "attachment-load-context-data"

static void
attachment_load_from_mime_part_thread (GSimpleAsyncResult *simple,
                                       GObject *object,
                                       GCancellable *cancellable)
{
    LoadContext *load_context;
    GFileInfo *file_info;
    EAttachment *attachment;
    CamelContentType *content_type;
    CamelMimePart *mime_part;
    const gchar *attribute;
    const gchar *string;
    gchar *allocated, *decoded_string = NULL;
    CamelStream *null;
    CamelDataWrapper *dw;

    load_context = g_object_get_data (
        G_OBJECT (simple), ATTACHMENT_LOAD_CONTEXT);
    g_return_if_fail (load_context != NULL);
    g_object_set_data (G_OBJECT (simple), ATTACHMENT_LOAD_CONTEXT, NULL);

    attachment = load_context->attachment;
    mime_part = e_attachment_ref_mime_part (attachment);

    file_info = g_file_info_new ();
    load_context->file_info = file_info;

    content_type = camel_mime_part_get_content_type (mime_part);
    allocated = camel_content_type_simple (content_type);
    if (allocated != NULL) {
        GIcon *icon;
        gchar *cp;

        /* GIO expects lowercase MIME types. */
        for (cp = allocated; *cp != '\0'; cp++)
            *cp = g_ascii_tolower (*cp);

        /* Swap the MIME type for a content type. */
        cp = g_content_type_from_mime_type (allocated);
        g_free (allocated);
        allocated = cp;

        /* Use the MIME part's filename if we have to. */
        if (g_content_type_is_unknown (allocated)) {
            string = camel_mime_part_get_filename (mime_part);
            if (string != NULL) {
                g_free (allocated);
                allocated = g_content_type_guess (
                    string, NULL, 0, NULL);
            }
        }

        g_file_info_set_content_type (file_info, allocated);

        icon = g_content_type_get_icon (allocated);
        if (icon != NULL) {
            g_file_info_set_icon (file_info, icon);
            g_object_unref (icon);
        }
    }
    g_free (allocated);

    /* Strip any path components from the filename. */
    string = camel_mime_part_get_filename (mime_part);
    if (string == NULL) {
        /* Translators: Default attachment filename. */
        string = _("attachment.dat");

        if (camel_content_type_is (content_type, "message", "rfc822")) {
            CamelMimeMessage *msg = NULL;
            const gchar *subject = NULL;

            if (CAMEL_IS_MIME_MESSAGE (mime_part)) {
                msg = CAMEL_MIME_MESSAGE (mime_part);
            } else {
                CamelDataWrapper *content;

                content = camel_medium_get_content (
                    CAMEL_MEDIUM (mime_part));
                if (CAMEL_IS_MIME_MESSAGE (content))
                    msg = CAMEL_MIME_MESSAGE (content);
            }

            if (msg != NULL)
                subject = camel_mime_message_get_subject (msg);

            if (subject != NULL && *subject != '\0')
                string = subject;
        }
    } else {
        decoded_string = camel_header_decode_string (string, "UTF-8");
        if (decoded_string && *decoded_string && !g_str_equal (decoded_string, string)) {
            string = decoded_string;
        } else {
            g_free (decoded_string);
            decoded_string = NULL;
        }
    }
    allocated = g_path_get_basename (string);
    g_file_info_set_display_name (file_info, allocated);
    g_free (decoded_string);
    g_free (allocated);

    attribute = G_FILE_ATTRIBUTE_STANDARD_DESCRIPTION;
    string = camel_mime_part_get_description (mime_part);
    if (string != NULL)
        g_file_info_set_attribute_string (
            file_info, attribute, string);

    dw = camel_medium_get_content (CAMEL_MEDIUM (mime_part));
    null = camel_stream_null_new ();
    /* this actually downloads the part and makes it available later */
    camel_data_wrapper_decode_to_stream_sync (
        dw, null, attachment->priv->cancellable, NULL);
    g_file_info_set_size (file_info, CAMEL_STREAM_NULL (null)->written);
    g_object_unref (null);

    load_context->mime_part = g_object_ref (mime_part);

    /* make sure it's freed on operation end */
    g_object_unref (load_context->simple);
    load_context->simple = NULL;

    g_simple_async_result_set_op_res_gpointer (
        simple, load_context,
        (GDestroyNotify) attachment_load_context_free);

    g_clear_object (&mime_part);
}

void
e_attachment_load_async (EAttachment *attachment,
                         GAsyncReadyCallback callback,
                         gpointer user_data)
{
    LoadContext *load_context;
    GCancellable *cancellable;
    CamelMimePart *mime_part;
    GFile *file;

    g_return_if_fail (E_IS_ATTACHMENT (attachment));

    if (e_attachment_get_loading (attachment)) {
        g_simple_async_report_error_in_idle (
            G_OBJECT (attachment), callback, user_data,
            G_IO_ERROR, G_IO_ERROR_BUSY,
            _("A load operation is already in progress"));
        return;
    }

    if (e_attachment_get_saving (attachment)) {
        g_simple_async_report_error_in_idle (
            G_OBJECT (attachment), callback, user_data,
            G_IO_ERROR, G_IO_ERROR_BUSY,
            _("A save operation is already in progress"));
        return;
    }

    file = e_attachment_ref_file (attachment);
    mime_part = e_attachment_ref_mime_part (attachment);
    g_return_if_fail (file != NULL || mime_part != NULL);

    load_context = attachment_load_context_new (
        attachment, callback, user_data);

    cancellable = attachment->priv->cancellable;
    g_cancellable_reset (cancellable);

    if (file != NULL) {
        g_file_query_info_async (
            file, ATTACHMENT_QUERY,
            G_FILE_QUERY_INFO_NONE,G_PRIORITY_DEFAULT,
            cancellable, (GAsyncReadyCallback)
            attachment_load_query_info_cb, load_context);

    } else if (mime_part != NULL) {
        g_object_set_data (
            G_OBJECT (load_context->simple),
            ATTACHMENT_LOAD_CONTEXT, load_context);

        g_simple_async_result_run_in_thread (
            load_context->simple,
            attachment_load_from_mime_part_thread,
            G_PRIORITY_DEFAULT,
            cancellable);
    }

    g_clear_object (&file);
    g_clear_object (&mime_part);
}

gboolean
e_attachment_load_finish (EAttachment *attachment,
                          GAsyncResult *result,
                          GError **error)
{
    GSimpleAsyncResult *simple;
    const LoadContext *load_context;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), FALSE);
    g_return_val_if_fail (G_IS_SIMPLE_ASYNC_RESULT (result), FALSE);

    simple = G_SIMPLE_ASYNC_RESULT (result);
    load_context = g_simple_async_result_get_op_res_gpointer (simple);

    if (load_context != NULL && load_context->mime_part != NULL) {
        const gchar *string;

        string = camel_mime_part_get_disposition (
            load_context->mime_part);
        e_attachment_set_disposition (attachment, string);

        e_attachment_set_file_info (
            attachment, load_context->file_info);
        e_attachment_set_mime_part (
            attachment, load_context->mime_part);
    }

    g_simple_async_result_propagate_error (simple, error);

    attachment_set_loading (attachment, FALSE);

    return (load_context != NULL);
}

void
e_attachment_load_handle_error (EAttachment *attachment,
                                GAsyncResult *result,
                                GtkWindow *parent)
{
    GtkWidget *dialog;
    GFileInfo *file_info;
    GtkTreeRowReference *reference;
    const gchar *display_name;
    const gchar *primary_text;
    GError *error = NULL;

    g_return_if_fail (E_IS_ATTACHMENT (attachment));
    g_return_if_fail (G_IS_ASYNC_RESULT (result));
    g_return_if_fail (!parent || GTK_IS_WINDOW (parent));

    if (e_attachment_load_finish (attachment, result, &error))
        return;

    /* XXX Calling EAttachmentStore functions from here violates
     *     the abstraction, but for now it's not hurting anything. */
    reference = e_attachment_get_reference (attachment);
    if (gtk_tree_row_reference_valid (reference)) {
        GtkTreeModel *model;

        model = gtk_tree_row_reference_get_model (reference);

        e_attachment_store_remove_attachment (
            E_ATTACHMENT_STORE (model), attachment);
    }

    /* Ignore cancellations. */
    if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED)) {
        g_error_free (error);
        return;
    }

    file_info = e_attachment_ref_file_info (attachment);

    if (file_info != NULL)
        display_name = g_file_info_get_display_name (file_info);
    else
        display_name = NULL;

    if (display_name != NULL)
        primary_text = g_strdup_printf (
            _("Could not load '%s'"), display_name);
    else
        primary_text = g_strdup_printf (
            _("Could not load the attachment"));

    g_clear_object (&file_info);

    dialog = gtk_message_dialog_new_with_markup (
        parent, GTK_DIALOG_DESTROY_WITH_PARENT,
        GTK_MESSAGE_ERROR, GTK_BUTTONS_OK,
        "<big><b>%s</b></big>", primary_text);

    gtk_message_dialog_format_secondary_text (
        GTK_MESSAGE_DIALOG (dialog), "%s", error->message);

    gtk_dialog_run (GTK_DIALOG (dialog));

    gtk_widget_destroy (dialog);
    g_error_free (error);
}

gboolean
e_attachment_load (EAttachment *attachment,
                   GError **error)
{
    EAsyncClosure *closure;
    GAsyncResult *result;
    gboolean success;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), FALSE);

    closure = e_async_closure_new ();

    e_attachment_load_async (attachment, e_async_closure_callback, closure);

    result = e_async_closure_wait (closure);

    success = e_attachment_load_finish (attachment, result, error);

    e_async_closure_free (closure);

    return success;
}

/************************* e_attachment_open_async() *************************/

typedef struct _OpenContext OpenContext;

struct _OpenContext {
    EAttachment *attachment;
    GSimpleAsyncResult *simple;

    GAppInfo *app_info;
};

static OpenContext *
attachment_open_context_new (EAttachment *attachment,
                             GAsyncReadyCallback callback,
                             gpointer user_data)
{
    OpenContext *open_context;
    GSimpleAsyncResult *simple;

    simple = g_simple_async_result_new (
        G_OBJECT (attachment), callback,
        user_data, e_attachment_open_async);

    open_context = g_slice_new0 (OpenContext);
    open_context->attachment = g_object_ref (attachment);
    open_context->simple = simple;

    return open_context;
}

static void
attachment_open_context_free (OpenContext *open_context)
{
    g_object_unref (open_context->attachment);
    g_object_unref (open_context->simple);

    if (open_context->app_info != NULL)
        g_object_unref (open_context->app_info);

    g_slice_free (OpenContext, open_context);
}

static gboolean
attachment_open_check_for_error (OpenContext *open_context,
                                 GError *error)
{
    GSimpleAsyncResult *simple;

    if (error == NULL)
        return FALSE;

    simple = open_context->simple;
    g_simple_async_result_take_error (simple, error);
    g_simple_async_result_complete (simple);

    attachment_open_context_free (open_context);

    return TRUE;
}

static void
attachment_open_file (GFile *file,
                      OpenContext *open_context)
{
    GdkAppLaunchContext *context;
    GSimpleAsyncResult *simple;
    GdkDisplay *display;
    gboolean success;
    GError *error = NULL;

    simple = open_context->simple;

    display = gdk_display_get_default ();
    context = gdk_display_get_app_launch_context (display);

    if (open_context->app_info != NULL) {
        GList *file_list;

        file_list = g_list_prepend (NULL, file);
        success = g_app_info_launch (
            open_context->app_info, file_list,
            G_APP_LAUNCH_CONTEXT (context), &error);
        g_list_free (file_list);
    } else {
        gchar *uri;

        uri = g_file_get_uri (file);
        success = g_app_info_launch_default_for_uri (
            uri, G_APP_LAUNCH_CONTEXT (context), &error);
        g_free (uri);
    }

    g_object_unref (context);

    g_simple_async_result_set_op_res_gboolean (simple, success);

    if (error != NULL)
        g_simple_async_result_take_error (simple, error);

    g_simple_async_result_complete (simple);
    attachment_open_context_free (open_context);
}

static void
attachment_open_save_finished_cb (EAttachment *attachment,
                                  GAsyncResult *result,
                                  OpenContext *open_context)
{
    GFile *file;
    gchar *path;
    GError *error = NULL;

    file = e_attachment_save_finish (attachment, result, &error);

    if (attachment_open_check_for_error (open_context, error))
        return;

    /* Make the temporary file read-only.
     *
     * This step is non-critical, so if an error occurs just
     * emit a warning and move on.
     *
     * XXX I haven't figured out how to do this through GIO.
     *     Attempting to set the "access::can-write" attribute via
     *     g_file_set_attribute() returned G_IO_ERROR_NOT_SUPPORTED
     *     and the only other possibility I see is "unix::mode",
     *     which is obviously not portable.
     */
    path = g_file_get_path (file);
#ifndef G_OS_WIN32
    if (g_chmod (path, S_IRUSR | S_IRGRP | S_IROTH) < 0)
        g_warning ("%s", g_strerror (errno));
#endif
    g_free (path);

    attachment_open_file (file, open_context);
    g_object_unref (file);
}

static void
attachment_open_save_temporary (OpenContext *open_context)
{
    GFile *temp_directory;
    gchar *template;
    gchar *path;
    GError *error = NULL;

    errno = 0;

    /* Save the file to a temporary directory.
     * We use a directory so the files can retain their basenames.
     * XXX This could trigger a blocking temp directory cleanup. */
    template = g_strdup_printf (PACKAGE "-%s-XXXXXX", g_get_user_name ());
    path = e_mkdtemp (template);
    g_free (template);

    /* XXX Let's hope errno got set properly. */
    if (path == NULL)
        g_set_error (
            &error, G_FILE_ERROR,
            g_file_error_from_errno (errno),
            "%s", g_strerror (errno));

    /* We already know if there's an error, but this does the cleanup. */
    if (attachment_open_check_for_error (open_context, error))
        return;

    temp_directory = g_file_new_for_path (path);

    e_attachment_save_async (
        open_context->attachment,
        temp_directory, (GAsyncReadyCallback)
        attachment_open_save_finished_cb, open_context);

    g_object_unref (temp_directory);
    g_free (path);
}

void
e_attachment_open_async (EAttachment *attachment,
                         GAppInfo *app_info,
                         GAsyncReadyCallback callback,
                         gpointer user_data)
{
    OpenContext *open_context;
    CamelMimePart *mime_part;
    GFile *file;

    g_return_if_fail (E_IS_ATTACHMENT (attachment));

    file = e_attachment_ref_file (attachment);
    mime_part = e_attachment_ref_mime_part (attachment);
    g_return_if_fail (file != NULL || mime_part != NULL);

    open_context = attachment_open_context_new (
        attachment, callback, user_data);

    if (G_IS_APP_INFO (app_info))
        open_context->app_info = g_object_ref (app_info);

    /* If the attachment already references a GFile, we can launch
     * the application directly.  Otherwise we have to save the MIME
     * part to a temporary file and launch the application from that. */
    if (file != NULL) {
        attachment_open_file (file, open_context);

    } else if (mime_part != NULL)
        attachment_open_save_temporary (open_context);

    g_clear_object (&file);
    g_clear_object (&mime_part);
}

gboolean
e_attachment_open_finish (EAttachment *attachment,
                          GAsyncResult *result,
                          GError **error)
{
    GSimpleAsyncResult *simple;
    gboolean success;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), FALSE);
    g_return_val_if_fail (G_IS_SIMPLE_ASYNC_RESULT (result), FALSE);

    simple = G_SIMPLE_ASYNC_RESULT (result);
    success = g_simple_async_result_get_op_res_gboolean (simple);
    g_simple_async_result_propagate_error (simple, error);

    return success;
}

void
e_attachment_open_handle_error (EAttachment *attachment,
                                GAsyncResult *result,
                                GtkWindow *parent)
{
    GtkWidget *dialog;
    GFileInfo *file_info;
    const gchar *display_name;
    const gchar *primary_text;
    GError *error = NULL;

    g_return_if_fail (E_IS_ATTACHMENT (attachment));
    g_return_if_fail (G_IS_ASYNC_RESULT (result));
    g_return_if_fail (GTK_IS_WINDOW (parent));

    if (e_attachment_open_finish (attachment, result, &error))
        return;

    /* Ignore cancellations. */
    if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
        return;

    file_info = e_attachment_ref_file_info (attachment);

    if (file_info != NULL)
        display_name = g_file_info_get_display_name (file_info);
    else
        display_name = NULL;

    if (display_name != NULL)
        primary_text = g_strdup_printf (
            _("Could not open '%s'"), display_name);
    else
        primary_text = g_strdup_printf (
            _("Could not open the attachment"));

    g_clear_object (&file_info);

    dialog = gtk_message_dialog_new_with_markup (
        parent, GTK_DIALOG_DESTROY_WITH_PARENT,
        GTK_MESSAGE_ERROR, GTK_BUTTONS_OK,
        "<big><b>%s</b></big>", primary_text);

    gtk_message_dialog_format_secondary_text (
        GTK_MESSAGE_DIALOG (dialog), "%s", error->message);

    gtk_dialog_run (GTK_DIALOG (dialog));

    gtk_widget_destroy (dialog);
    g_error_free (error);
}

gboolean
e_attachment_open (EAttachment *attachment,
                   GAppInfo *app_info,
                   GError **error)
{
    EAsyncClosure *closure;
    GAsyncResult *result;
    gboolean success;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), FALSE);

    closure = e_async_closure_new ();

    e_attachment_open_async (attachment, app_info, e_async_closure_callback, closure);

    result = e_async_closure_wait (closure);

    success = e_attachment_open_finish (attachment, result, error);

    e_async_closure_free (closure);

    return success;
}

/************************* e_attachment_save_async() *************************/

typedef struct _SaveContext SaveContext;

struct _SaveContext {
    EAttachment *attachment;
    GSimpleAsyncResult *simple;

    GFile *directory;
    GFile *destination;
    GInputStream *input_stream;
    GOutputStream *output_stream;
    goffset total_num_bytes;
    gssize bytes_read;
    gchar buffer[4096];
    gint count;
};

/* Forward Declaration */
static void
attachment_save_read_cb (GInputStream *input_stream,
                         GAsyncResult *result,
                         SaveContext *save_context);

static SaveContext *
attachment_save_context_new (EAttachment *attachment,
                             GAsyncReadyCallback callback,
                             gpointer user_data)
{
    SaveContext *save_context;
    GSimpleAsyncResult *simple;

    simple = g_simple_async_result_new (
        G_OBJECT (attachment), callback,
        user_data, e_attachment_save_async);

    save_context = g_slice_new0 (SaveContext);
    save_context->attachment = g_object_ref (attachment);
    save_context->simple = simple;

    attachment_set_saving (save_context->attachment, TRUE);

    return save_context;
}

static void
attachment_save_context_free (SaveContext *save_context)
{
    g_object_unref (save_context->attachment);
    g_object_unref (save_context->simple);

    if (save_context->directory != NULL)
        g_object_unref (save_context->directory);

    if (save_context->destination != NULL)
        g_object_unref (save_context->destination);

    if (save_context->input_stream != NULL)
        g_object_unref (save_context->input_stream);

    if (save_context->output_stream != NULL)
        g_object_unref (save_context->output_stream);

    g_slice_free (SaveContext, save_context);
}

static gboolean
attachment_save_check_for_error (SaveContext *save_context,
                                 GError *error)
{
    GSimpleAsyncResult *simple;

    if (error == NULL)
        return FALSE;

    simple = save_context->simple;
    g_simple_async_result_take_error (simple, error);
    g_simple_async_result_complete (simple);

    attachment_save_context_free (save_context);

    return TRUE;
}

static GFile *
attachment_save_new_candidate (SaveContext *save_context)
{
    GFile *candidate;
    GFileInfo *file_info;
    EAttachment *attachment;
    const gchar *display_name = NULL;
    gchar *basename;

    attachment = save_context->attachment;
    file_info = e_attachment_ref_file_info (attachment);

    if (file_info != NULL)
        display_name = g_file_info_get_display_name (file_info);
    if (display_name == NULL)
        /* Translators: Default attachment filename. */
        display_name = _("attachment.dat");

    if (save_context->count == 0)
        basename = g_strdup (display_name);
    else {
        GString *string;
        const gchar *ext;
        gsize length;

        string = g_string_sized_new (strlen (display_name));
        ext = g_utf8_strchr (display_name, -1, '.');

        if (ext != NULL)
            length = ext - display_name;
        else
            length = strlen (display_name);

        g_string_append_len (string, display_name, length);
        g_string_append_printf (string, " (%d)", save_context->count);
        g_string_append (string, (ext != NULL) ? ext : "");

        basename = g_string_free (string, FALSE);
    }

    save_context->count++;

    candidate = g_file_get_child (save_context->directory, basename);

    g_free (basename);

    g_clear_object (&file_info);

    return candidate;
}

static void
attachment_save_write_cb (GOutputStream *output_stream,
                          GAsyncResult *result,
                          SaveContext *save_context)
{
    EAttachment *attachment;
    GCancellable *cancellable;
    GInputStream *input_stream;
    gssize bytes_written;
    GError *error = NULL;

    bytes_written = g_output_stream_write_finish (
        output_stream, result, &error);

    if (attachment_save_check_for_error (save_context, error))
        return;

    attachment = save_context->attachment;
    cancellable = attachment->priv->cancellable;
    input_stream = save_context->input_stream;

    if (bytes_written < save_context->bytes_read) {
        g_memmove (
            save_context->buffer,
            save_context->buffer + bytes_written,
            save_context->bytes_read - bytes_written);
        save_context->bytes_read -= bytes_written;

        g_output_stream_write_async (
            output_stream,
            save_context->buffer,
            save_context->bytes_read,
            G_PRIORITY_DEFAULT, cancellable,
            (GAsyncReadyCallback) attachment_save_write_cb,
            save_context);
    } else
        g_input_stream_read_async (
            input_stream,
            save_context->buffer,
            sizeof (save_context->buffer),
            G_PRIORITY_DEFAULT, cancellable,
            (GAsyncReadyCallback) attachment_save_read_cb,
            save_context);
}

static void
attachment_save_read_cb (GInputStream *input_stream,
                         GAsyncResult *result,
                         SaveContext *save_context)
{
    EAttachment *attachment;
    GCancellable *cancellable;
    GOutputStream *output_stream;
    gssize bytes_read;
    GError *error = NULL;

    bytes_read = g_input_stream_read_finish (
        input_stream, result, &error);

    if (attachment_save_check_for_error (save_context, error))
        return;

    if (bytes_read == 0) {
        GSimpleAsyncResult *simple;
        GFile *destination;

        /* Steal the destination. */
        destination = save_context->destination;
        save_context->destination = NULL;

        simple = save_context->simple;
        g_simple_async_result_set_op_res_gpointer (
            simple, destination, (GDestroyNotify) g_object_unref);
        g_simple_async_result_complete (simple);

        attachment_save_context_free (save_context);

        return;
    }

    attachment = save_context->attachment;
    cancellable = attachment->priv->cancellable;
    output_stream = save_context->output_stream;
    save_context->bytes_read = bytes_read;

    attachment_progress_cb (
        g_seekable_tell (G_SEEKABLE (input_stream)),
        save_context->total_num_bytes, attachment);

    g_output_stream_write_async (
        output_stream,
        save_context->buffer,
        save_context->bytes_read,
        G_PRIORITY_DEFAULT, cancellable,
        (GAsyncReadyCallback) attachment_save_write_cb,
        save_context);
}

static void
attachment_save_got_output_stream (SaveContext *save_context)
{
    GCancellable *cancellable;
    GInputStream *input_stream;
    CamelDataWrapper *wrapper;
    CamelMimePart *mime_part;
    CamelStream *stream;
    EAttachment *attachment;
    GByteArray *buffer;

    attachment = save_context->attachment;
    cancellable = attachment->priv->cancellable;
    mime_part = e_attachment_ref_mime_part (attachment);

    /* Decode the MIME part to an in-memory buffer.  We have to do
     * this because CamelStream is synchronous-only, and using threads
     * is dangerous because CamelDataWrapper is not reentrant. */
    buffer = g_byte_array_new ();
    stream = camel_stream_mem_new ();
    camel_stream_mem_set_byte_array (CAMEL_STREAM_MEM (stream), buffer);
    wrapper = camel_medium_get_content (CAMEL_MEDIUM (mime_part));
    camel_data_wrapper_decode_to_stream_sync (wrapper, stream, NULL, NULL);
    g_object_unref (stream);

    /* Load the buffer into a GMemoryInputStream.
     * But watch out for zero length MIME parts. */
    input_stream = g_memory_input_stream_new ();
    if (buffer->len > 0)
        g_memory_input_stream_add_data (
            G_MEMORY_INPUT_STREAM (input_stream),
            buffer->data, (gssize) buffer->len,
            (GDestroyNotify) g_free);
    save_context->input_stream = input_stream;
    save_context->total_num_bytes = (goffset) buffer->len;
    g_byte_array_free (buffer, FALSE);

    g_input_stream_read_async (
        input_stream,
        save_context->buffer,
        sizeof (save_context->buffer),
        G_PRIORITY_DEFAULT, cancellable,
        (GAsyncReadyCallback) attachment_save_read_cb,
        save_context);

    g_clear_object (&mime_part);
}

static void
attachment_save_create_cb (GFile *destination,
                           GAsyncResult *result,
                           SaveContext *save_context)
{
    EAttachment *attachment;
    GCancellable *cancellable;
    GFileOutputStream *output_stream;
    GError *error = NULL;

    /* Output stream might be NULL, so don't use cast macro. */
    output_stream = g_file_create_finish (destination, result, &error);
    save_context->output_stream = (GOutputStream *) output_stream;

    attachment = save_context->attachment;
    cancellable = attachment->priv->cancellable;

    if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_EXISTS)) {
        destination = attachment_save_new_candidate (save_context);

        g_file_create_async (
            destination, G_FILE_CREATE_NONE,
            G_PRIORITY_DEFAULT, cancellable,
            (GAsyncReadyCallback) attachment_save_create_cb,
            save_context);

        g_object_unref (destination);
        g_error_free (error);
        return;
    }

    if (attachment_save_check_for_error (save_context, error))
        return;

    save_context->destination = g_object_ref (destination);
    attachment_save_got_output_stream (save_context);
}

static void
attachment_save_replace_cb (GFile *destination,
                            GAsyncResult *result,
                            SaveContext *save_context)
{
    GFileOutputStream *output_stream;
    GError *error = NULL;

    /* Output stream might be NULL, so don't use cast macro. */
    output_stream = g_file_replace_finish (destination, result, &error);
    save_context->output_stream = (GOutputStream *) output_stream;

    if (attachment_save_check_for_error (save_context, error))
        return;

    save_context->destination = g_object_ref (destination);
    attachment_save_got_output_stream (save_context);
}

static void
attachment_save_query_info_cb (GFile *destination,
                               GAsyncResult *result,
                               SaveContext *save_context)
{
    EAttachment *attachment;
    GCancellable *cancellable;
    GFileInfo *file_info;
    GFileType file_type;
    GError *error = NULL;

    attachment = save_context->attachment;
    cancellable = attachment->priv->cancellable;

    file_info = g_file_query_info_finish (destination, result, &error);

    /* G_IO_ERROR_NOT_FOUND just means we're creating a new file. */
    if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_NOT_FOUND)) {
        g_error_free (error);
        goto replace;
    }

    if (attachment_save_check_for_error (save_context, error))
        return;

    file_type = g_file_info_get_file_type (file_info);
    g_object_unref (file_info);

    if (file_type == G_FILE_TYPE_DIRECTORY) {
        save_context->directory = g_object_ref (destination);
        destination = attachment_save_new_candidate (save_context);

        g_file_create_async (
            destination, G_FILE_CREATE_NONE,
            G_PRIORITY_DEFAULT, cancellable,
            (GAsyncReadyCallback) attachment_save_create_cb,
            save_context);

        g_object_unref (destination);

        return;
    }

replace:
    g_file_replace_async (
        destination, NULL, FALSE,
        G_FILE_CREATE_REPLACE_DESTINATION,
        G_PRIORITY_DEFAULT, cancellable,
        (GAsyncReadyCallback) attachment_save_replace_cb,
        save_context);
}

void
e_attachment_save_async (EAttachment *attachment,
                         GFile *destination,
                         GAsyncReadyCallback callback,
                         gpointer user_data)
{
    SaveContext *save_context;
    GCancellable *cancellable;

    g_return_if_fail (E_IS_ATTACHMENT (attachment));
    g_return_if_fail (G_IS_FILE (destination));

    if (e_attachment_get_loading (attachment)) {
        g_simple_async_report_error_in_idle (
            G_OBJECT (attachment), callback, user_data,
            G_IO_ERROR, G_IO_ERROR_BUSY,
            _("A load operation is already in progress"));
        return;
    }

    if (e_attachment_get_saving (attachment)) {
        g_simple_async_report_error_in_idle (
            G_OBJECT (attachment), callback, user_data,
            G_IO_ERROR, G_IO_ERROR_BUSY,
            _("A save operation is already in progress"));
        return;
    }

    /* Just peek, don't reference. */
    if (attachment->priv->mime_part == NULL) {
        g_simple_async_report_error_in_idle (
            G_OBJECT (attachment), callback, user_data,
            G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
            _("Attachment contents not loaded"));
        return;
    }

    save_context = attachment_save_context_new (
        attachment, callback, user_data);

    cancellable = attachment->priv->cancellable;
    g_cancellable_reset (cancellable);

    /* First we need to know if destination is a directory. */
    g_file_query_info_async (
        destination, G_FILE_ATTRIBUTE_STANDARD_TYPE,
        G_FILE_QUERY_INFO_NONE, G_PRIORITY_DEFAULT,
        cancellable, (GAsyncReadyCallback)
        attachment_save_query_info_cb, save_context);
}

GFile *
e_attachment_save_finish (EAttachment *attachment,
                          GAsyncResult *result,
                          GError **error)
{
    GSimpleAsyncResult *simple;
    GFile *destination;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), NULL);
    g_return_val_if_fail (G_IS_SIMPLE_ASYNC_RESULT (result), NULL);

    simple = G_SIMPLE_ASYNC_RESULT (result);
    destination = g_simple_async_result_get_op_res_gpointer (simple);
    if (destination != NULL)
        g_object_ref (destination);
    g_simple_async_result_propagate_error (simple, error);

    attachment_set_saving (attachment, FALSE);

    return destination;
}

void
e_attachment_save_handle_error (EAttachment *attachment,
                                GAsyncResult *result,
                                GtkWindow *parent)
{
    GFile *file;
    GFileInfo *file_info;
    GtkWidget *dialog;
    const gchar *display_name;
    const gchar *primary_text;
    GError *error = NULL;

    g_return_if_fail (E_IS_ATTACHMENT (attachment));
    g_return_if_fail (G_IS_ASYNC_RESULT (result));
    g_return_if_fail (GTK_IS_WINDOW (parent));

    file = e_attachment_save_finish (attachment, result, &error);

    if (file != NULL) {
        g_object_unref (file);
        return;
    }

    /* Ignore cancellations. */
    if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
        return;

    file_info = e_attachment_ref_file_info (attachment);

    if (file_info != NULL)
        display_name = g_file_info_get_display_name (file_info);
    else
        display_name = NULL;

    if (display_name != NULL)
        primary_text = g_strdup_printf (
            _("Could not save '%s'"), display_name);
    else
        primary_text = g_strdup_printf (
            _("Could not save the attachment"));

    g_clear_object (&file_info);

    dialog = gtk_message_dialog_new_with_markup (
        parent, GTK_DIALOG_DESTROY_WITH_PARENT,
        GTK_MESSAGE_ERROR, GTK_BUTTONS_OK,
        "<big><b>%s</b></big>", primary_text);

    gtk_message_dialog_format_secondary_text (
        GTK_MESSAGE_DIALOG (dialog), "%s", error->message);

    gtk_dialog_run (GTK_DIALOG (dialog));

    gtk_widget_destroy (dialog);
    g_error_free (error);
}

gboolean
e_attachment_save (EAttachment *attachment,
                   GFile *in_destination,
                   GFile **out_destination,
                   GError **error)
{
    EAsyncClosure *closure;
    GAsyncResult *result;

    g_return_val_if_fail (E_IS_ATTACHMENT (attachment), FALSE);
    g_return_val_if_fail (out_destination != NULL, FALSE);

    closure = e_async_closure_new ();

    e_attachment_save_async (attachment, in_destination, e_async_closure_callback, closure);

    result = e_async_closure_wait (closure);

    *out_destination = e_attachment_save_finish (attachment, result, error);

    e_async_closure_free (closure);

    return *out_destination != NULL;
}