/* GIO - GLib Input, Output and Streaming Library
 *
 * Copyright 2010 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 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/>.
 */

#include "config.h"
#include "gtlsinputstream-gnutls.h"

static void g_tls_input_stream_gnutls_pollable_iface_init (GPollableInputStreamInterface *iface);

G_DEFINE_TYPE_WITH_CODE (GTlsInputStreamGnutls, g_tls_input_stream_gnutls, G_TYPE_INPUT_STREAM,
			 G_IMPLEMENT_INTERFACE (G_TYPE_POLLABLE_INPUT_STREAM, g_tls_input_stream_gnutls_pollable_iface_init)
			 )

struct _GTlsInputStreamGnutlsPrivate
{
  GTlsConnectionGnutls *conn;

  /* pending operation metadata */
  GCancellable *cancellable;
  gpointer buffer;
  gsize count;
};

static void
g_tls_input_stream_gnutls_dispose (GObject *object)
{
  GTlsInputStreamGnutls *stream = G_TLS_INPUT_STREAM_GNUTLS (object);

  if (stream->priv->conn)
    {
      g_object_remove_weak_pointer (G_OBJECT (stream->priv->conn),
				    (gpointer *)&stream->priv->conn);
      stream->priv->conn = NULL;
    }

  G_OBJECT_CLASS (g_tls_input_stream_gnutls_parent_class)->dispose (object);
}

static gssize
g_tls_input_stream_gnutls_read (GInputStream  *stream,
				void          *buffer,
				gsize          count,
				GCancellable  *cancellable,
				GError       **error)
{
  GTlsInputStreamGnutls *tls_stream = G_TLS_INPUT_STREAM_GNUTLS (stream);

  g_return_val_if_fail (tls_stream->priv->conn != NULL, -1);

  return g_tls_connection_gnutls_read (tls_stream->priv->conn,
				       buffer, count, TRUE,
				       cancellable, error);
}

static gboolean
g_tls_input_stream_gnutls_read_ready (GPollableInputStream *stream,
				      gpointer              user_data)
{
  GTlsInputStreamGnutls *tls_stream;
  GSimpleAsyncResult *simple = user_data;
  gssize nread;
  GError *error = NULL;

  tls_stream = G_TLS_INPUT_STREAM_GNUTLS (g_async_result_get_source_object (G_ASYNC_RESULT (simple)));
  g_object_unref (tls_stream);

  nread = g_tls_connection_gnutls_read (tls_stream->priv->conn,
					tls_stream->priv->buffer,
					tls_stream->priv->count, FALSE,
					tls_stream->priv->cancellable,
					&error);
  if (nread == -1 &&
      g_error_matches (error, G_IO_ERROR, G_IO_ERROR_WOULD_BLOCK))
    {
      g_error_free (error);
      return TRUE;
    }

  if (error)
    {
      g_simple_async_result_set_from_error (simple, error);
      g_error_free (error);
    }
  else
    g_simple_async_result_set_op_res_gssize (simple, nread);

  if (tls_stream->priv->cancellable)
    g_object_unref (tls_stream->priv->cancellable);
  g_simple_async_result_complete (simple);
  g_object_unref (simple);

  return FALSE;
}

static void
g_tls_input_stream_gnutls_read_async (GInputStream        *stream,
				      void                *buffer,
				      gsize                count,
				      gint                 io_priority,
				      GCancellable        *cancellable,
				      GAsyncReadyCallback  callback,
				      gpointer             user_data)
{
  GTlsInputStreamGnutls *tls_stream = G_TLS_INPUT_STREAM_GNUTLS (stream);
  GSimpleAsyncResult *simple;
  gssize nread;
  GError *error = NULL;
  GSource *source;

  g_return_if_fail (tls_stream->priv->conn != NULL);

  simple = g_simple_async_result_new (G_OBJECT (stream), callback, user_data,
				      g_tls_input_stream_gnutls_read_async);
  nread = g_tls_connection_gnutls_read (tls_stream->priv->conn,
					buffer, count, FALSE,
					cancellable, &error);

  if (nread >= 0 ||
      !g_error_matches (error, G_IO_ERROR, G_IO_ERROR_WOULD_BLOCK))
    {
      if (error)
	{
	  g_simple_async_result_set_from_error (simple, error);
	  g_error_free (error);
	}
      else
	g_simple_async_result_set_op_res_gssize (simple, nread);
      g_simple_async_result_complete_in_idle (simple);
      g_object_unref (simple);
      return;
    }

  if (error)
    g_error_free (error);

  tls_stream->priv->cancellable = cancellable ? g_object_ref (cancellable) : NULL;
  tls_stream->priv->buffer = buffer;
  tls_stream->priv->count = count;

  source = g_tls_connection_gnutls_create_source (tls_stream->priv->conn,
						  G_IO_IN,
						  tls_stream->priv->cancellable);
  g_source_set_callback (source,
			 (GSourceFunc) g_tls_input_stream_gnutls_read_ready,
			 simple, NULL);
  g_source_attach (source, g_main_context_get_thread_default ());
  g_source_unref (source);
}

static gssize
g_tls_input_stream_gnutls_read_finish (GInputStream  *stream,
				       GAsyncResult  *result,
				       GError       **error)
{
  g_return_val_if_fail (G_IS_TLS_INPUT_STREAM_GNUTLS (stream), -1);
  g_return_val_if_fail (g_simple_async_result_is_valid (result, G_OBJECT (stream), g_tls_input_stream_gnutls_read_async), -1);

  return g_simple_async_result_get_op_res_gssize (G_SIMPLE_ASYNC_RESULT (result));
}

static gboolean
g_tls_input_stream_gnutls_pollable_is_readable (GPollableInputStream *pollable)
{
  GTlsInputStreamGnutls *tls_stream = G_TLS_INPUT_STREAM_GNUTLS (pollable);

  g_return_val_if_fail (tls_stream->priv->conn != NULL, FALSE);

  return g_tls_connection_gnutls_check (tls_stream->priv->conn, G_IO_IN); 
}

static GSource *
g_tls_input_stream_gnutls_pollable_create_source (GPollableInputStream *pollable,
						  GCancellable         *cancellable)
{
  GTlsInputStreamGnutls *tls_stream = G_TLS_INPUT_STREAM_GNUTLS (pollable);

  g_return_val_if_fail (tls_stream->priv->conn != NULL, NULL);

  return g_tls_connection_gnutls_create_source (tls_stream->priv->conn,
						G_IO_IN,
						cancellable);
}

static gssize
g_tls_input_stream_gnutls_pollable_read_nonblocking (GPollableInputStream  *pollable,
						     void                  *buffer,
						     gsize                  size,
						     GError               **error)
{
  GTlsInputStreamGnutls *tls_stream = G_TLS_INPUT_STREAM_GNUTLS (pollable);

  return g_tls_connection_gnutls_read (tls_stream->priv->conn,
				       buffer, size, FALSE,
				       NULL, error);
}

static void
g_tls_input_stream_gnutls_class_init (GTlsInputStreamGnutlsClass *klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  GInputStreamClass *input_stream_class = G_INPUT_STREAM_CLASS (klass);

  g_type_class_add_private (klass, sizeof (GTlsInputStreamGnutlsPrivate));

  gobject_class->dispose = g_tls_input_stream_gnutls_dispose;

  input_stream_class->read_fn = g_tls_input_stream_gnutls_read;
  input_stream_class->read_async = g_tls_input_stream_gnutls_read_async;
  input_stream_class->read_finish = g_tls_input_stream_gnutls_read_finish;
}

static void
g_tls_input_stream_gnutls_pollable_iface_init (GPollableInputStreamInterface *iface)
{
  iface->is_readable = g_tls_input_stream_gnutls_pollable_is_readable;
  iface->create_source = g_tls_input_stream_gnutls_pollable_create_source;
  iface->read_nonblocking = g_tls_input_stream_gnutls_pollable_read_nonblocking;
}

static void
g_tls_input_stream_gnutls_init (GTlsInputStreamGnutls *stream)
{
  stream->priv = G_TYPE_INSTANCE_GET_PRIVATE (stream, G_TYPE_TLS_INPUT_STREAM_GNUTLS, GTlsInputStreamGnutlsPrivate);
}

GInputStream *
g_tls_input_stream_gnutls_new (GTlsConnectionGnutls *conn)
{
  GTlsInputStreamGnutls *tls_stream;

  tls_stream = g_object_new (G_TYPE_TLS_INPUT_STREAM_GNUTLS, NULL);
  tls_stream->priv->conn = conn;
  g_object_add_weak_pointer (G_OBJECT (conn),
			     (gpointer *)&tls_stream->priv->conn);

  return G_INPUT_STREAM (tls_stream);
}