/*

 * libvirt-gobject-output-stream.h: libvirt gobject integration

 *

 * Copyright (C) 2011 Red Hat, Inc.

 *

 * This library 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 2.1 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library. If not, see

 * <http://www.gnu.org/licenses/>.

 *

 * Authors: Daniel P. Berrange <berrange@redhat.com>

 *          Marc-André Lureau <marcandre.lureau@redhat.com>

 */

#include <config.h>

#include <libvirt/virterror.h>

#include <string.h>

#include "libvirt-glib/libvirt-glib.h"

#include "libvirt-gobject/libvirt-gobject.h"

#include "libvirt-gobject-output-stream.h"

#include "libvirt-gobject-compat.h"

enum

{

    PROP_0,

    PROP_STREAM

};

struct _GVirOutputStreamPrivate

{

    GVirStream *stream;

    /* pending operation metadata */

    GTask *task;

    const void * buffer;

    gsize count;

};

#define gvir_output_stream_get_type _gvir_output_stream_get_type

G_DEFINE_TYPE_WITH_PRIVATE(GVirOutputStream, gvir_output_stream, G_TYPE_OUTPUT_STREAM);

static void gvir_output_stream_get_property(GObject *object,

                                            guint prop_id,

                                            GValue *value,

                                            GParamSpec *pspec)

{

    GVirOutputStream *stream = GVIR_OUTPUT_STREAM(object);

    switch (prop_id) {

    case PROP_STREAM:

        g_value_set_object(value, stream->priv->stream);

        break;

    default:

        G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);

    }

}

static void gvir_output_stream_set_property(GObject *object,

                                            guint prop_id,

                                            const GValue *value,

                                            GParamSpec *pspec)

{

    GVirOutputStream *stream = GVIR_OUTPUT_STREAM(object);

    switch (prop_id) {

    case PROP_STREAM:

        stream->priv->stream = g_value_get_object(value);

        break;

    default:

        G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);

    }

}

static void gvir_output_stream_finalize(GObject *object)

{

    GVirOutputStream *stream = GVIR_OUTPUT_STREAM(object);

    stream->priv->stream = NULL; // unowned

    if (G_OBJECT_CLASS(gvir_output_stream_parent_class)->finalize)

        (*G_OBJECT_CLASS(gvir_output_stream_parent_class)->finalize)(object);

}

static gboolean

gvir_output_stream_write_ready(GVirStream *stream,

                               GVirStreamIOCondition cond,

                               void *opaque)

{

    GVirOutputStream *output_stream = GVIR_OUTPUT_STREAM(opaque);

    GVirOutputStreamPrivate *priv = output_stream->priv;

    GTask *task = priv->task;

    GCancellable *cancellable = g_task_get_cancellable(task);

    GError *error = NULL;

    gssize result;

    if (!(cond & GVIR_STREAM_IO_CONDITION_WRITABLE)) {

        g_warn_if_reached();

        g_task_return_new_error(task,

                                G_IO_ERROR,

                                G_IO_ERROR_INVALID_ARGUMENT,

                                "%s",

                                "Expected stream to be readable");

        goto cleanup;

    }

    result  = gvir_stream_send(stream, priv->buffer, priv->count,

                               cancellable, &error);

    if (error != NULL) {

        if (g_error_matches(error, G_IO_ERROR, G_IO_ERROR_WOULD_BLOCK)) {

            g_warn_if_reached();

            g_task_return_new_error(task,

                                    G_IO_ERROR,

                                    G_IO_ERROR_INVALID_ARGUMENT,

                                    "%s",

                                    "Expected stream to be writable");

            g_error_free (error);

        } else {

            g_task_return_error(task, error);

        }

        goto cleanup;

    }

    g_task_return_int(task, result);

cleanup:

    priv->task = NULL;

    g_object_unref(task);

    return FALSE;

}

static void gvir_output_stream_write_async(GOutputStream *stream,

                                           const void *buffer,

                                           gsize count,

                                           int io_priority G_GNUC_UNUSED,

                                           GCancellable *cancellable,

                                           GAsyncReadyCallback callback,

                                           gpointer user_data)

{

    GVirOutputStream *output_stream = GVIR_OUTPUT_STREAM(stream);

    g_return_if_fail(GVIR_IS_OUTPUT_STREAM(stream));

    g_return_if_fail(output_stream->priv->task == NULL);

    gvir_stream_add_watch_full(output_stream->priv->stream,

                               G_PRIORITY_DEFAULT,

                               GVIR_STREAM_IO_CONDITION_WRITABLE,

                               gvir_output_stream_write_ready,

                               g_object_ref(stream),

                               (GDestroyNotify)g_object_unref);

    output_stream->priv->task =

        g_task_new(stream, cancellable, callback, user_data);

    output_stream->priv->buffer = buffer;

    output_stream->priv->count = count;

}

static gssize gvir_output_stream_write_finish(GOutputStream *stream,

                                              GAsyncResult *result,

                                              GError **error)

{

    GVirOutputStream *output_stream = GVIR_OUTPUT_STREAM(stream);

    virStreamPtr handle;

    gssize count;

    g_return_val_if_fail(GVIR_IS_OUTPUT_STREAM(stream), -1);

    g_return_val_if_fail(g_task_is_valid(result, stream), -1);

    g_return_val_if_fail(error == NULL || *error == NULL, -1);

    g_object_get(output_stream->priv->stream, "handle", &handle, NULL);

    count = g_task_propagate_int(G_TASK(result), error);

    virStreamFree(handle);

    return count;

}

static void gvir_output_stream_class_init(GVirOutputStreamClass *klass)

{

    GObjectClass *gobject_class = G_OBJECT_CLASS(klass);

    GOutputStreamClass *goutputstream_class = G_OUTPUT_STREAM_CLASS(klass);

    gobject_class->finalize = gvir_output_stream_finalize;

    gobject_class->get_property = gvir_output_stream_get_property;

    gobject_class->set_property = gvir_output_stream_set_property;

    goutputstream_class->write_fn = NULL;

    goutputstream_class->write_async = gvir_output_stream_write_async;

    goutputstream_class->write_finish = gvir_output_stream_write_finish;

    g_object_class_install_property(gobject_class, PROP_STREAM,

                                    g_param_spec_object("stream",

                                                        "stream",

                                                        "GVirStream",

                                                        GVIR_TYPE_STREAM, G_PARAM_CONSTRUCT_ONLY |

                                                        G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

}

static void gvir_output_stream_init(GVirOutputStream *stream)

{

    stream->priv = G_TYPE_INSTANCE_GET_PRIVATE(stream, GVIR_TYPE_OUTPUT_STREAM, GVirOutputStreamPrivate);

}

GVirOutputStream* _gvir_output_stream_new(GVirStream *stream)

{

    return GVIR_OUTPUT_STREAM(g_object_new(GVIR_TYPE_OUTPUT_STREAM, "stream", stream, NULL));

}