/* GStreamer

 *

 * Copyright (C) 2007 Rene Stadler <mail@renestadler.de>

 * Copyright (C) 2007-2009 Sebastian Dröge <sebastian.droege@collabora.co.uk>

 * 

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library 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

 * Library General Public License for more details.

 *

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

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif

#include "gstgiobasesrc.h"

#include <gst/base/gsttypefindhelper.h>

GST_DEBUG_CATEGORY_STATIC (gst_gio_base_src_debug);

#define GST_CAT_DEFAULT gst_gio_base_src_debug

static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src",

    GST_PAD_SRC,

    GST_PAD_ALWAYS,

    GST_STATIC_CAPS_ANY);

#define gst_gio_base_src_parent_class parent_class

G_DEFINE_TYPE (GstGioBaseSrc, gst_gio_base_src, GST_TYPE_BASE_SRC);

static void gst_gio_base_src_finalize (GObject * object);

static gboolean gst_gio_base_src_start (GstBaseSrc * base_src);

static gboolean gst_gio_base_src_stop (GstBaseSrc * base_src);

static gboolean gst_gio_base_src_get_size (GstBaseSrc * base_src,

    guint64 * size);

static gboolean gst_gio_base_src_is_seekable (GstBaseSrc * base_src);

static gboolean gst_gio_base_src_unlock (GstBaseSrc * base_src);

static gboolean gst_gio_base_src_unlock_stop (GstBaseSrc * base_src);

static GstFlowReturn gst_gio_base_src_create (GstBaseSrc * base_src,

    guint64 offset, guint size, GstBuffer ** buf);

static gboolean gst_gio_base_src_query (GstBaseSrc * base_src,

    GstQuery * query);

static void

gst_gio_base_src_class_init (GstGioBaseSrcClass * klass)

{

  GObjectClass *gobject_class = (GObjectClass *) klass;

  GstElementClass *gstelement_class = (GstElementClass *) klass;

  GstBaseSrcClass *gstbasesrc_class = (GstBaseSrcClass *) klass;

  GST_DEBUG_CATEGORY_INIT (gst_gio_base_src_debug, "gio_base_src", 0,

      "GIO base source");

  gobject_class->finalize = gst_gio_base_src_finalize;

  gst_element_class_add_static_pad_template (gstelement_class, &src_factory);

  gstbasesrc_class->start = GST_DEBUG_FUNCPTR (gst_gio_base_src_start);

  gstbasesrc_class->stop = GST_DEBUG_FUNCPTR (gst_gio_base_src_stop);

  gstbasesrc_class->get_size = GST_DEBUG_FUNCPTR (gst_gio_base_src_get_size);

  gstbasesrc_class->is_seekable =

      GST_DEBUG_FUNCPTR (gst_gio_base_src_is_seekable);

  gstbasesrc_class->unlock = GST_DEBUG_FUNCPTR (gst_gio_base_src_unlock);

  gstbasesrc_class->unlock_stop =

      GST_DEBUG_FUNCPTR (gst_gio_base_src_unlock_stop);

  gstbasesrc_class->create = GST_DEBUG_FUNCPTR (gst_gio_base_src_create);

  gstbasesrc_class->query = GST_DEBUG_FUNCPTR (gst_gio_base_src_query);

}

static void

gst_gio_base_src_init (GstGioBaseSrc * src)

{

  src->cancel = g_cancellable_new ();

}

static void

gst_gio_base_src_finalize (GObject * object)

{

  GstGioBaseSrc *src = GST_GIO_BASE_SRC (object);

  if (src->cancel) {

    g_object_unref (src->cancel);

    src->cancel = NULL;

  }

  if (src->stream) {

    g_object_unref (src->stream);

    src->stream = NULL;

  }

  if (src->cache) {

    gst_buffer_unref (src->cache);

    src->cache = NULL;

  }

  GST_CALL_PARENT (G_OBJECT_CLASS, finalize, (object));

}

static gboolean

gst_gio_base_src_start (GstBaseSrc * base_src)

{

  GstGioBaseSrc *src = GST_GIO_BASE_SRC (base_src);

  GstGioBaseSrcClass *gbsrc_class = GST_GIO_BASE_SRC_GET_CLASS (src);

  src->position = 0;

  /* FIXME: This will likely block */

  src->stream = gbsrc_class->get_stream (src);

  if (G_UNLIKELY (!G_IS_INPUT_STREAM (src->stream))) {

    GST_ELEMENT_ERROR (src, RESOURCE, OPEN_READ, (NULL),

        ("No input stream provided by subclass"));

    return FALSE;

  } else if (G_UNLIKELY (g_input_stream_is_closed (src->stream))) {

    GST_ELEMENT_ERROR (src, LIBRARY, FAILED, (NULL),

        ("Input stream is already closed"));

    return FALSE;

  }

  if (G_IS_SEEKABLE (src->stream))

    src->position = g_seekable_tell (G_SEEKABLE (src->stream));

  GST_DEBUG_OBJECT (src, "started source");

  return TRUE;

}

static gboolean

gst_gio_base_src_stop (GstBaseSrc * base_src)

{

  GstGioBaseSrc *src = GST_GIO_BASE_SRC (base_src);

  GstGioBaseSrcClass *klass = GST_GIO_BASE_SRC_GET_CLASS (src);

  gboolean success;

  GError *err = NULL;

  if (klass->close_on_stop && G_IS_INPUT_STREAM (src->stream)) {

    GST_DEBUG_OBJECT (src, "closing stream");

    /* FIXME: can block but unfortunately we can't use async operations

     * here because they require a running main loop */

    success = g_input_stream_close (src->stream, src->cancel, &err;;

    if (!success && !gst_gio_error (src, "g_input_stream_close", &err, NULL)) {

      GST_ELEMENT_WARNING (src, RESOURCE, CLOSE, (NULL),

          ("g_input_stream_close failed: %s", err->message));

      g_clear_error (&err;;

    } else if (!success) {

      GST_ELEMENT_WARNING (src, RESOURCE, CLOSE, (NULL),

          ("g_input_stream_close failed"));

    } else {

      GST_DEBUG_OBJECT (src, "g_input_stream_close succeeded");

    }

    g_object_unref (src->stream);

    src->stream = NULL;

  } else {

    g_object_unref (src->stream);

    src->stream = NULL;

  }

  return TRUE;

}

static gboolean

gst_gio_base_src_get_size (GstBaseSrc * base_src, guint64 * size)

{

  GstGioBaseSrc *src = GST_GIO_BASE_SRC (base_src);

  if (G_IS_FILE_INPUT_STREAM (src->stream)) {

    GFileInfo *info;

    GError *err = NULL;

    info = g_file_input_stream_query_info (G_FILE_INPUT_STREAM (src->stream),

        G_FILE_ATTRIBUTE_STANDARD_SIZE, src->cancel, &err;;

    if (info != NULL) {

      *size = g_file_info_get_size (info);

      g_object_unref (info);

      GST_DEBUG_OBJECT (src, "found size: %" G_GUINT64_FORMAT, *size);

      return TRUE;

    }

    if (!gst_gio_error (src, "g_file_input_stream_query_info", &err, NULL)) {

      if (GST_GIO_ERROR_MATCHES (err, NOT_SUPPORTED))

        GST_DEBUG_OBJECT (src, "size information not available");

      else

        GST_WARNING_OBJECT (src, "size information retrieval failed: %s",

            err->message);

      g_clear_error (&err;;

    }

  }

  if (GST_GIO_STREAM_IS_SEEKABLE (src->stream)) {

    goffset old;

    goffset stream_size;

    gboolean ret;

    GSeekable *seekable = G_SEEKABLE (src->stream);

    GError *err = NULL;

    old = g_seekable_tell (seekable);

    ret = g_seekable_seek (seekable, 0, G_SEEK_END, src->cancel, &err;;

    if (!ret) {

      if (!gst_gio_error (src, "g_seekable_seek", &err, NULL)) {

        if (GST_GIO_ERROR_MATCHES (err, NOT_SUPPORTED))

          GST_DEBUG_OBJECT (src,

              "Seeking to the end of stream is not supported");

        else

          GST_WARNING_OBJECT (src, "Seeking to end of stream failed: %s",

              err->message);

        g_clear_error (&err;;

      } else {

        GST_WARNING_OBJECT (src, "Seeking to end of stream failed");

      }

      return FALSE;

    }

    stream_size = g_seekable_tell (seekable);

    ret = g_seekable_seek (seekable, old, G_SEEK_SET, src->cancel, &err;;

    if (!ret) {

      if (!gst_gio_error (src, "g_seekable_seek", &err, NULL)) {

        if (GST_GIO_ERROR_MATCHES (err, NOT_SUPPORTED))

          GST_ERROR_OBJECT (src, "Seeking to the old position not supported");

        else

          GST_ERROR_OBJECT (src, "Seeking to the old position failed: %s",

              err->message);

        g_clear_error (&err;;

      } else {

        GST_ERROR_OBJECT (src, "Seeking to the old position faile");

      }

      return FALSE;

    }

    if (stream_size >= 0) {

      *size = stream_size;

      return TRUE;

    }

  }

  return FALSE;

}

static gboolean

gst_gio_base_src_is_seekable (GstBaseSrc * base_src)

{

  GstGioBaseSrc *src = GST_GIO_BASE_SRC (base_src);

  gboolean seekable;

  seekable = GST_GIO_STREAM_IS_SEEKABLE (src->stream);

  GST_DEBUG_OBJECT (src, "can seek: %d", seekable);

  return seekable;

}

static gboolean

gst_gio_base_src_unlock (GstBaseSrc * base_src)

{

  GstGioBaseSrc *src = GST_GIO_BASE_SRC (base_src);

  GST_LOG_OBJECT (src, "triggering cancellation");

  g_cancellable_cancel (src->cancel);

  return TRUE;

}

static gboolean

gst_gio_base_src_unlock_stop (GstBaseSrc * base_src)

{

  GstGioBaseSrc *src = GST_GIO_BASE_SRC (base_src);

  GST_LOG_OBJECT (src, "resetting cancellable");

  g_object_unref (src->cancel);

  src->cancel = g_cancellable_new ();

  return TRUE;

}

static GstFlowReturn

gst_gio_base_src_create (GstBaseSrc * base_src, guint64 offset, guint size,

    GstBuffer ** buf_return)

{

  GstGioBaseSrc *src = GST_GIO_BASE_SRC (base_src);

  GstBuffer *buf;

  GstFlowReturn ret = GST_FLOW_OK;

  g_return_val_if_fail (G_IS_INPUT_STREAM (src->stream), GST_FLOW_ERROR);

  /* If we have the requested part in our cache take a subbuffer of that,

   * otherwise fill the cache again with at least 4096 bytes from the

   * requested offset and return a subbuffer of that.

   *

   * We need caching because every read/seek operation will need to go

   * over DBus if our backend is GVfs and this is painfully slow. */

  if (src->cache && offset >= GST_BUFFER_OFFSET (src->cache) &&

      offset + size <= GST_BUFFER_OFFSET_END (src->cache)) {

    GST_DEBUG_OBJECT (src, "Creating subbuffer from cached buffer: offset %"

        G_GUINT64_FORMAT " length %u", offset, size);

    buf = gst_buffer_copy_region (src->cache, GST_BUFFER_COPY_ALL,

        offset - GST_BUFFER_OFFSET (src->cache), size);

    GST_BUFFER_OFFSET (buf) = offset;

    GST_BUFFER_OFFSET_END (buf) = offset + size;

  } else {

    guint cachesize = MAX (4096, size);

    GstMapInfo map;

    gssize read, streamread, res;

    guint64 readoffset;

    gboolean success, eos;

    GError *err = NULL;

    GstBuffer *newbuffer;

    GstMemory *mem;

    newbuffer = gst_buffer_new ();

    /* copy any overlapping data from the cached buffer */

    if (src->cache && offset >= GST_BUFFER_OFFSET (src->cache) &&

        offset <= GST_BUFFER_OFFSET_END (src->cache)) {

      read = GST_BUFFER_OFFSET_END (src->cache) - offset;

      GST_LOG_OBJECT (src,

          "Copying %" G_GSSIZE_FORMAT " bytes from cached buffer at %"

          G_GUINT64_FORMAT, read, offset - GST_BUFFER_OFFSET (src->cache));

      gst_buffer_copy_into (newbuffer, src->cache, GST_BUFFER_COPY_MEMORY,

          offset - GST_BUFFER_OFFSET (src->cache), read);

    } else {

      read = 0;

    }

    if (src->cache)

      gst_buffer_unref (src->cache);

    src->cache = newbuffer;

    readoffset = offset + read;

    GST_LOG_OBJECT (src,

        "Reading %u bytes from offset %" G_GUINT64_FORMAT, cachesize,

        readoffset);

    if (G_UNLIKELY (readoffset != src->position)) {

      if (!GST_GIO_STREAM_IS_SEEKABLE (src->stream))

        return GST_FLOW_NOT_SUPPORTED;

      GST_DEBUG_OBJECT (src, "Seeking to position %" G_GUINT64_FORMAT,

          readoffset);

      ret =

          gst_gio_seek (src, G_SEEKABLE (src->stream), readoffset, src->cancel);

      if (ret == GST_FLOW_OK)

        src->position = readoffset;

      else

        return ret;

    }

    /* GIO sometimes gives less bytes than requested although

     * it's not at the end of file. SMB for example only

     * supports reads up to 64k. So we loop here until we get at

     * at least the requested amount of bytes or a read returns

     * nothing. */

    mem = gst_allocator_alloc (NULL, cachesize, NULL);

    if (mem == NULL) {

      GST_ERROR_OBJECT (src, "Failed to allocate %u bytes", cachesize);

      return GST_FLOW_ERROR;

    }

    gst_memory_map (mem, &map, GST_MAP_WRITE);

    streamread = 0;

    while (size - read > 0 && (res =

            g_input_stream_read (G_INPUT_STREAM (src->stream),

                map.data + streamread, cachesize - streamread, src->cancel,

                &err)) > 0) {

      read += res;

      streamread += res;

      src->position += res;

    }

    gst_memory_unmap (mem, &map);

    gst_buffer_append_memory (src->cache, mem);

    success = (read >= 0);

    eos = (cachesize > 0 && read == 0);

    if (!success && !gst_gio_error (src, "g_input_stream_read", &err, &ret)) {

      GST_ELEMENT_ERROR (src, RESOURCE, READ, (NULL),

          ("Could not read from stream: %s", err->message));

      g_clear_error (&err;;

    }

    if (success && !eos) {

      GST_BUFFER_OFFSET (src->cache) = offset;

      GST_BUFFER_OFFSET_END (src->cache) = offset + read;

      GST_DEBUG_OBJECT (src, "Read successful");

      GST_DEBUG_OBJECT (src, "Creating subbuffer from new "

          "cached buffer: offset %" G_GUINT64_FORMAT " length %u", offset,

          size);

      buf =

          gst_buffer_copy_region (src->cache, GST_BUFFER_COPY_ALL, 0, MIN (size,

              read));

      GST_BUFFER_OFFSET (buf) = offset;

      GST_BUFFER_OFFSET_END (buf) = offset + MIN (size, read);

    } else {

      GST_DEBUG_OBJECT (src, "Read not successful");

      gst_buffer_unref (src->cache);

      src->cache = NULL;

      buf = NULL;

    }

    if (eos)

      ret = GST_FLOW_EOS;

  }

  *buf_return = buf;

  return ret;

}

static gboolean

gst_gio_base_src_query (GstBaseSrc * base_src, GstQuery * query)

{

  gboolean ret = FALSE;

  GstGioBaseSrc *src = GST_GIO_BASE_SRC (base_src);

  switch (GST_QUERY_TYPE (query)) {

    case GST_QUERY_URI:

      if (GST_IS_URI_HANDLER (src)) {

        gchar *uri = gst_uri_handler_get_uri (GST_URI_HANDLER (src));

        gst_query_set_uri (query, uri);

        g_free (uri);

        ret = TRUE;

      }

      break;

    default:

      ret = FALSE;

      break;

  }

  if (!ret)

    ret = GST_BASE_SRC_CLASS (parent_class)->query (base_src, query);

  return ret;

}