/* GStreamer
 * Copyright (C) 2006 David A. Schleef <ds@schleef.org>
 *
 * gstlistfilesrc.c:
 *
 * 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., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */
/**
 * SECTION:element-listfilesrc
 * @see_also: #GstFileSrc
 *
 * Reads buffers from files named in a list file, one per line. If used together
 * with an image decoder, one needs to use the #GstListFileSrc:caps property or
 * a capsfilter to force to caps containing a framerate. Otherwise image decoders
 * send EOS after the first picture.
 *
 * <refsect2>
 * <title>Example launch line</title>
 * |[
 * gst-launch listfilesrc location=imagelist index=0 caps="image/png,framerate=\(fraction\)12/1" ! \
 *     pngdec ! ffmpegcolorspace ! theoraenc ! oggmux ! \
 *     filesink location="images.ogg"
 * ]| This pipeline creates a video file "images.ogg" by joining PNG
 * files named in the file 'imagelist'.
 * </refsect2>
*/

#ifdef HAVE_CONFIG_H
#  include "config.h"
#endif

#include "gstlistfilesrc.h"


static GstFlowReturn gst_list_file_src_create (GstPushSrc * src,
    GstBuffer ** buffer);

static void gst_list_file_src_dispose (GObject * object);

static void gst_list_file_src_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec);
static void gst_list_file_src_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec);
static GstCaps *gst_list_file_src_getcaps (GstBaseSrc * src);
static gboolean gst_list_file_src_query (GstBaseSrc * src, GstQuery * query);


static GstStaticPadTemplate gst_list_file_src_pad_template =
GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS_ANY);

GST_DEBUG_CATEGORY_STATIC (gst_list_file_src_debug);
#define GST_CAT_DEFAULT gst_list_file_src_debug

enum
{
  ARG_0,
  ARG_LOCATION,
  ARG_INDEX,
  ARG_CAPS
};

#define DEFAULT_INDEX 0


GST_BOILERPLATE (GstListFileSrc, gst_list_file_src, GstPushSrc,
    GST_TYPE_PUSH_SRC);

static void
gst_list_file_src_base_init (gpointer g_class)
{
  GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);

  GST_DEBUG_CATEGORY_INIT (gst_list_file_src_debug, "listfilesrc", 0,
      "listfilesrc element");

  gst_element_class_add_pad_template (gstelement_class,
      gst_static_pad_template_get (&gst_list_file_src_pad_template));
  gst_element_class_set_details_simple (gstelement_class, "List-File Source",
      "Source/File",
      "Read a set of files named in a list file into buffers",
      "David Schleef <ds@schleef.org>");
}

static void
gst_list_file_src_class_init (GstListFileSrcClass * klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  GstPushSrcClass *gstpushsrc_class = GST_PUSH_SRC_CLASS (klass);
  GstBaseSrcClass *gstbasesrc_class = GST_BASE_SRC_CLASS (klass);

  gobject_class->set_property = gst_list_file_src_set_property;
  gobject_class->get_property = gst_list_file_src_get_property;

  g_object_class_install_property (gobject_class, ARG_LOCATION,
      g_param_spec_string ("location", "File Location",
          "Name of the list file. The list file must contain the names of "
	  "the source files, one per line.", NULL, G_PARAM_READWRITE));
  g_object_class_install_property (gobject_class, ARG_INDEX,
      g_param_spec_int ("index", "File Index",
          "Index to use with location property to create file names.  The "
          "index is incremented by one for each buffer read.",
          0, INT_MAX, DEFAULT_INDEX, G_PARAM_READWRITE));
  g_object_class_install_property (gobject_class, ARG_CAPS,
      g_param_spec_boxed ("caps", "Caps",
          "Caps describing the format of the data.",
          GST_TYPE_CAPS, G_PARAM_READWRITE));

  gobject_class->dispose = gst_list_file_src_dispose;

  gstbasesrc_class->get_caps = gst_list_file_src_getcaps;
  gstbasesrc_class->query = gst_list_file_src_query;

  gstpushsrc_class->create = gst_list_file_src_create;

  if (sizeof (off_t) < 8) {
    GST_LOG ("No large file support, sizeof (off_t) = %" G_GSIZE_FORMAT,
        sizeof (off_t));
  }
}

static void
gst_list_file_src_init (GstListFileSrc * listfilesrc,
    GstListFileSrcClass * g_class)
{
  listfilesrc->index = DEFAULT_INDEX;
  listfilesrc->successful_read = FALSE;
}

static void
gst_list_file_src_dispose (GObject * object)
{
  GstListFileSrc *src = GST_LIST_FILE_SRC (object);

  g_free (src->filename);
  src->filename = NULL;
  g_strfreev (src->filelist);
  src->filelist = NULL;
  if (src->caps)
    gst_caps_unref (src->caps);

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

static GstCaps *
gst_list_file_src_getcaps (GstBaseSrc * src)
{
  GstListFileSrc *list_file_src = GST_LIST_FILE_SRC (src);

  GST_DEBUG_OBJECT (src, "returning %" GST_PTR_FORMAT, list_file_src->caps);

  if (list_file_src->caps) {
    return gst_caps_ref (list_file_src->caps);
  } else {
    return gst_caps_new_any ();
  }
}

static gboolean
gst_list_file_src_query (GstBaseSrc * src, GstQuery * query)
{
  gboolean res;
  GstListFileSrc *mfsrc;

  mfsrc = GST_LIST_FILE_SRC (src);

  switch (GST_QUERY_TYPE (query)) {
    case GST_QUERY_POSITION:
    {
      GstFormat format;

      gst_query_parse_position (query, &format, NULL);
      switch (format) {
        case GST_FORMAT_BUFFERS:
        case GST_FORMAT_DEFAULT:
          gst_query_set_position (query, GST_FORMAT_BUFFERS, mfsrc->index);
          res = TRUE;
          break;
        default:
          res = GST_BASE_SRC_CLASS (parent_class)->query (src, query);
          break;
      }
      break;
    }
    default:
      res = GST_BASE_SRC_CLASS (parent_class)->query (src, query);
      break;
  }
  return res;
}

static gboolean
gst_list_file_src_set_location (GstListFileSrc * src, const gchar * location)
{
  g_free (src->filename);
  g_strfreev (src->filelist);
  src->filelist = NULL;
  if (location != NULL) {
    gboolean ret;
    gchar *data;
    gsize size;

    src->filename = g_strdup (location);
    ret = g_file_get_contents (src->filename, &data, &size, NULL);
    if (!ret) {
      GST_DEBUG_OBJECT (src, "unable to read list file %s", src->filename);
      return FALSE;
    }

    src->filelist = g_strsplit (data, "\n", 0);
    g_free (data);

  } else {
    src->filename = NULL;
  }

  return TRUE;
}

static void
gst_list_file_src_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstListFileSrc *src = GST_LIST_FILE_SRC (object);

  switch (prop_id) {
    case ARG_LOCATION:
      gst_list_file_src_set_location (src, g_value_get_string (value));
      break;
    case ARG_INDEX:
      src->index = g_value_get_int (value);
      break;
    case ARG_CAPS:
    {
      const GstCaps *caps = gst_value_get_caps (value);
      GstCaps *new_caps;

      if (caps == NULL) {
        new_caps = gst_caps_new_any ();
      } else {
        new_caps = gst_caps_copy (caps);
      }
      gst_caps_replace (&src->caps, new_caps);
      gst_pad_set_caps (GST_BASE_SRC_PAD (src), new_caps);
    }
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_list_file_src_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec)
{
  GstListFileSrc *src = GST_LIST_FILE_SRC (object);

  switch (prop_id) {
    case ARG_LOCATION:
      g_value_set_string (value, src->filename);
      break;
    case ARG_INDEX:
      g_value_set_int (value, src->index);
      break;
    case ARG_CAPS:
      gst_value_set_caps (value, src->caps);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static const gchar *
gst_list_file_src_get_filename (GstListFileSrc * listfilesrc)
{
  if (listfilesrc->filelist == NULL) {
    return NULL;
  }
  return listfilesrc->filelist[listfilesrc->index];
}

static GstFlowReturn
gst_list_file_src_create (GstPushSrc * src, GstBuffer ** buffer)
{
  GstListFileSrc *listfilesrc;
  gsize size;
  gchar *data;
  const gchar *filename;
  GstBuffer *buf;
  gboolean ret;
  GError *error = NULL;

  listfilesrc = GST_LIST_FILE_SRC (src);

  filename = gst_list_file_src_get_filename (listfilesrc);
  if (filename == NULL) {
    GST_DEBUG_OBJECT (listfilesrc, "reached the end of the list");
    return GST_FLOW_UNEXPECTED;
  }

  GST_DEBUG_OBJECT (listfilesrc, "reading from file \"%s\".", filename);

  ret = g_file_get_contents (filename, &data, &size, &error);
  if (!ret) {
    if (listfilesrc->successful_read) {
      /* If we've read at least one buffer successfully, not finding the
       * next file is EOS. */
      if (error != NULL)
        g_error_free (error);
      return GST_FLOW_UNEXPECTED;
    } else {
      goto handle_error;
    }
  }

  listfilesrc->successful_read = TRUE;
  listfilesrc->index++;

  buf = gst_buffer_new ();
  GST_BUFFER_DATA (buf) = (unsigned char *) data;
  GST_BUFFER_MALLOCDATA (buf) = GST_BUFFER_DATA (buf);
  GST_BUFFER_SIZE (buf) = size;
  GST_BUFFER_OFFSET (buf) = listfilesrc->offset;
  GST_BUFFER_OFFSET_END (buf) = listfilesrc->offset + size;
  listfilesrc->offset += size;
  gst_buffer_set_caps (buf, listfilesrc->caps);

  GST_DEBUG_OBJECT (listfilesrc, "read file \"%s\".", filename);

  *buffer = buf;
  return GST_FLOW_OK;

handle_error:
  {
    if (error != NULL) {
      GST_ELEMENT_ERROR (listfilesrc, RESOURCE, READ,
          ("Error while reading from file \"%s\".", filename),
          ("%s", error->message));
      g_error_free (error);
    } else {
      GST_ELEMENT_ERROR (listfilesrc, RESOURCE, READ,
          ("Error while reading from file \"%s\".", filename),
          ("%s", g_strerror (errno)));
    }
    return GST_FLOW_ERROR;
  }
}
