/*
 * Copyright (C) 2017 Collabora Inc.
 *    Author: Nicolas Dufresne <nicolas.dufresne@collabora.com>
 *
 * 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 <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>

#include "gstv4l2object.h"
#include "gstv4l2mpeg4enc.h"

#include <string.h>
#include <gst/gst-i18n-plugin.h>

GST_DEBUG_CATEGORY_STATIC (gst_v4l2_mpeg4_enc_debug);
#define GST_CAT_DEFAULT gst_v4l2_mpeg4_enc_debug

static GstStaticCaps src_template_caps =
GST_STATIC_CAPS ("video/mpeg, mpegversion=(int)4, systemstream=(boolean)FALSE");

enum
{
  PROP_0,
  V4L2_STD_OBJECT_PROPS,
  /* TODO */
};

#define gst_v4l2_mpeg4_enc_parent_class parent_class
G_DEFINE_TYPE (GstV4l2Mpeg4Enc, gst_v4l2_mpeg4_enc, GST_TYPE_V4L2_VIDEO_ENC);

static void
gst_v4l2_mpeg4_enc_set_property (GObject * object,
    guint prop_id, const GValue * value, GParamSpec * pspec)
{
  /* TODO */
}

static void
gst_v4l2_mpeg4_enc_get_property (GObject * object,
    guint prop_id, GValue * value, GParamSpec * pspec)
{
  /* TODO */
}

static gint
v4l2_profile_from_string (const gchar * profile)
{
  gint v4l2_profile = -1;

  if (g_str_equal (profile, "simple"))
    v4l2_profile = V4L2_MPEG_VIDEO_MPEG4_PROFILE_SIMPLE;
  else if (g_str_equal (profile, "advanced-simple"))
    v4l2_profile = V4L2_MPEG_VIDEO_MPEG4_PROFILE_ADVANCED_SIMPLE;
  else if (g_str_equal (profile, "core"))
    v4l2_profile = V4L2_MPEG_VIDEO_MPEG4_PROFILE_CORE;
  else if (g_str_equal (profile, "simple-scalable"))
    v4l2_profile = V4L2_MPEG_VIDEO_MPEG4_PROFILE_SIMPLE_SCALABLE;
  else if (g_str_equal (profile, "advanced-coding-efficiency"))
    v4l2_profile = V4L2_MPEG_VIDEO_MPEG4_PROFILE_ADVANCED_CODING_EFFICIENCY;
  else
    GST_WARNING ("Unsupported profile string '%s'", profile);

  return v4l2_profile;
}

static const gchar *
v4l2_profile_to_string (gint v4l2_profile)
{
  switch (v4l2_profile) {
    case V4L2_MPEG_VIDEO_MPEG4_PROFILE_SIMPLE:
      return "simple";
    case V4L2_MPEG_VIDEO_MPEG4_PROFILE_ADVANCED_SIMPLE:
      return "advanced-simple";
    case V4L2_MPEG_VIDEO_MPEG4_PROFILE_CORE:
      return "core";
    case V4L2_MPEG_VIDEO_MPEG4_PROFILE_SIMPLE_SCALABLE:
      return "simple-scalable";
    case V4L2_MPEG_VIDEO_MPEG4_PROFILE_ADVANCED_CODING_EFFICIENCY:
      return "advanced-coding-efficiency";
    default:
      GST_WARNING ("Unsupported V4L2 profile %i", v4l2_profile);
      break;
  }

  return NULL;
}

static gint
v4l2_level_from_string (const gchar * level)
{
  gint v4l2_level = -1;

  if (g_str_equal (level, "0"))
    v4l2_level = V4L2_MPEG_VIDEO_MPEG4_LEVEL_0;
  else if (g_str_equal (level, "0b"))
    v4l2_level = V4L2_MPEG_VIDEO_MPEG4_LEVEL_0B;
  else if (g_str_equal (level, "1"))
    v4l2_level = V4L2_MPEG_VIDEO_MPEG4_LEVEL_1;
  else if (g_str_equal (level, "2"))
    v4l2_level = V4L2_MPEG_VIDEO_MPEG4_LEVEL_2;
  else if (g_str_equal (level, "3"))
    v4l2_level = V4L2_MPEG_VIDEO_MPEG4_LEVEL_3;
  else if (g_str_equal (level, "3b"))
    v4l2_level = V4L2_MPEG_VIDEO_MPEG4_LEVEL_3B;
  else if (g_str_equal (level, "4"))
    v4l2_level = V4L2_MPEG_VIDEO_MPEG4_LEVEL_4;
  else if (g_str_equal (level, "5"))
    v4l2_level = V4L2_MPEG_VIDEO_MPEG4_LEVEL_5;
  else
    GST_WARNING ("Unsupported level '%s'", level);

  return v4l2_level;
}

static const gchar *
v4l2_level_to_string (gint v4l2_level)
{
  switch (v4l2_level) {
    case V4L2_MPEG_VIDEO_MPEG4_LEVEL_0:
      return "0";
    case V4L2_MPEG_VIDEO_MPEG4_LEVEL_0B:
      return "0b";
    case V4L2_MPEG_VIDEO_MPEG4_LEVEL_1:
      return "1";
    case V4L2_MPEG_VIDEO_MPEG4_LEVEL_2:
      return "2";
    case V4L2_MPEG_VIDEO_MPEG4_LEVEL_3:
      return "3";
    case V4L2_MPEG_VIDEO_MPEG4_LEVEL_3B:
      return "3b";
    case V4L2_MPEG_VIDEO_MPEG4_LEVEL_4:
      return "4";
    case V4L2_MPEG_VIDEO_MPEG4_LEVEL_5:
      return "5";
    default:
      GST_WARNING ("Unsupported V4L2 level %i", v4l2_level);
      break;
  }

  return NULL;
}

struct ProfileLevelCtx
{
  GstV4l2Mpeg4Enc *self;
  const gchar *profile;
  const gchar *level;
};

static gboolean
get_string_list (GstStructure * s, const gchar * field, GQueue * queue)
{
  const GValue *value;

  value = gst_structure_get_value (s, field);

  if (!value)
    return FALSE;

  if (GST_VALUE_HOLDS_LIST (value)) {
    guint i;

    if (gst_value_list_get_size (value) == 0)
      return FALSE;

    for (i = 0; i < gst_value_list_get_size (value); i++) {
      const GValue *item = gst_value_list_get_value (value, i);

      if (G_VALUE_HOLDS_STRING (item))
        g_queue_push_tail (queue, g_value_dup_string (item));
    }
  } else if (G_VALUE_HOLDS_STRING (value)) {
    g_queue_push_tail (queue, g_value_dup_string (value));
  }

  return TRUE;
}

static gboolean
negotiate_profile_and_level (GstCapsFeatures * features, GstStructure * s,
    gpointer user_data)
{
  struct ProfileLevelCtx *ctx = user_data;
  GstV4l2Object *v4l2object = GST_V4L2_VIDEO_ENC (ctx->self)->v4l2output;
  GQueue profiles = G_QUEUE_INIT;
  GQueue levels = G_QUEUE_INIT;
  gboolean failed = FALSE;

  if (get_string_list (s, "profile", &profiles)) {
    GList *l;

    for (l = profiles.head; l; l = l->next) {
      struct v4l2_control control = { 0, };
      gint v4l2_profile;
      const gchar *profile = l->data;

      GST_TRACE_OBJECT (ctx->self, "Trying profile %s", profile);

      control.id = V4L2_CID_MPEG_VIDEO_MPEG4_PROFILE;
      control.value = v4l2_profile = v4l2_profile_from_string (profile);

      if (control.value < 0)
        continue;

      if (v4l2object->ioctl (v4l2object->video_fd, VIDIOC_S_CTRL, &control) < 0) {
        GST_WARNING_OBJECT (ctx->self, "Failed to set MPEG4 profile: '%s'",
            g_strerror (errno));
        break;
      }

      profile = v4l2_profile_to_string (control.value);

      if (control.value == v4l2_profile) {
        ctx->profile = profile;
        break;
      }

      if (g_list_find_custom (l, profile, g_str_equal)) {
        ctx->profile = profile;
        break;
      }
    }

    if (profiles.length && !ctx->profile)
      failed = TRUE;

    g_queue_foreach (&profiles, (GFunc) g_free, NULL);
    g_queue_clear (&profiles);
  }

  if (!failed && get_string_list (s, "level", &levels)) {
    GList *l;

    for (l = levels.head; l; l = l->next) {
      struct v4l2_control control = { 0, };
      gint v4l2_level;
      const gchar *level = l->data;

      GST_TRACE_OBJECT (ctx->self, "Trying level %s", level);

      control.id = V4L2_CID_MPEG_VIDEO_MPEG4_LEVEL;
      control.value = v4l2_level = v4l2_level_from_string (level);

      if (control.value < 0)
        continue;

      if (v4l2object->ioctl (v4l2object->video_fd, VIDIOC_S_CTRL, &control) < 0) {
        GST_WARNING_OBJECT (ctx->self, "Failed to set MPEG4 level: '%s'",
            g_strerror (errno));
        break;
      }

      level = v4l2_level_to_string (control.value);

      if (control.value == v4l2_level) {
        ctx->level = level;
        break;
      }

      if (g_list_find_custom (l, level, g_str_equal)) {
        ctx->level = level;
        break;
      }
    }

    if (levels.length && !ctx->level)
      failed = TRUE;

    g_queue_foreach (&levels, (GFunc) g_free, NULL);
    g_queue_clear (&levels);
  }

  /* If it failed, we continue */
  return failed;
}

static gboolean
gst_v4l2_mpeg4_enc_negotiate (GstVideoEncoder * encoder)
{
  GstV4l2Mpeg4Enc *self = GST_V4L2_MPEG4_ENC (encoder);
  GstV4l2VideoEnc *venc = GST_V4L2_VIDEO_ENC (encoder);
  GstV4l2Object *v4l2object = venc->v4l2output;
  GstCaps *allowed_caps;
  struct ProfileLevelCtx ctx = { self, NULL, NULL };
  GstVideoCodecState *state;
  GstStructure *s;

  GST_DEBUG_OBJECT (self, "Negotiating MPEG4 profile and level.");

  allowed_caps = gst_pad_get_allowed_caps (GST_VIDEO_ENCODER_SRC_PAD (encoder));

  if (allowed_caps) {

    if (gst_caps_is_empty (allowed_caps))
      goto not_negotiated;

    allowed_caps = gst_caps_make_writable (allowed_caps);

    /* negotiate_profile_and_level() will return TRUE on failure to keep
     * iterating, if gst_caps_foreach() returns TRUE it means there was no
     * compatible profile and level in any of the structure */
    if (gst_caps_foreach (allowed_caps, negotiate_profile_and_level, &ctx)) {
      goto no_profile_level;
    }
  }

  if (!ctx.profile) {
    struct v4l2_control control = { 0, };

    control.id = V4L2_CID_MPEG_VIDEO_MPEG4_PROFILE;

    if (v4l2object->ioctl (v4l2object->video_fd, VIDIOC_G_CTRL, &control) < 0)
      goto g_ctrl_failed;

    ctx.profile = v4l2_profile_to_string (control.value);
  }

  if (!ctx.level) {
    struct v4l2_control control = { 0, };

    control.id = V4L2_CID_MPEG_VIDEO_MPEG4_LEVEL;

    if (v4l2object->ioctl (v4l2object->video_fd, VIDIOC_G_CTRL, &control) < 0)
      goto g_ctrl_failed;

    ctx.level = v4l2_level_to_string (control.value);
  }

  GST_DEBUG_OBJECT (self, "Selected MPEG4 profile %s at level %s",
      ctx.profile, ctx.level);

  state = gst_video_encoder_get_output_state (encoder);
  s = gst_caps_get_structure (state->caps, 0);
  gst_structure_set (s, "profile", G_TYPE_STRING, ctx.profile,
      "level", G_TYPE_STRING, ctx.level, NULL);

  return GST_VIDEO_ENCODER_CLASS (parent_class)->negotiate (encoder);

g_ctrl_failed:
  GST_WARNING_OBJECT (self, "Failed to get MPEG4 profile and level: '%s'",
      g_strerror (errno));
  goto not_negotiated;

no_profile_level:
  GST_WARNING_OBJECT (self, "No compatible level and profiled in caps: %"
      GST_PTR_FORMAT, allowed_caps);
  goto not_negotiated;

not_negotiated:
  if (allowed_caps)
    gst_caps_unref (allowed_caps);
  return FALSE;
}

static void
gst_v4l2_mpeg4_enc_init (GstV4l2Mpeg4Enc * self)
{
}

static void
gst_v4l2_mpeg4_enc_class_init (GstV4l2Mpeg4EncClass * klass)
{
  GstElementClass *element_class;
  GObjectClass *gobject_class;
  GstVideoEncoderClass *baseclass;

  parent_class = g_type_class_peek_parent (klass);

  element_class = (GstElementClass *) klass;
  gobject_class = (GObjectClass *) klass;
  baseclass = GST_VIDEO_ENCODER_CLASS (klass);

  GST_DEBUG_CATEGORY_INIT (gst_v4l2_mpeg4_enc_debug, "v4l2mpeg4enc", 0,
      "V4L2 MPEG4 Encoder");

  gst_element_class_set_static_metadata (element_class,
      "V4L2 MPEG4 Encoder",
      "Codec/Encoder/Video",
      "Encode MPEG4 video streams via V4L2 API",
      "Nicolas Dufresne <nicolas.dufresne@collabora.com");

  gobject_class->set_property =
      GST_DEBUG_FUNCPTR (gst_v4l2_mpeg4_enc_set_property);
  gobject_class->get_property =
      GST_DEBUG_FUNCPTR (gst_v4l2_mpeg4_enc_get_property);
  baseclass->negotiate = GST_DEBUG_FUNCPTR (gst_v4l2_mpeg4_enc_negotiate);
}

/* Probing functions */
gboolean
gst_v4l2_is_mpeg4_enc (GstCaps * sink_caps, GstCaps * src_caps)
{
  return gst_v4l2_is_video_enc (sink_caps, src_caps,
      gst_static_caps_get (&src_template_caps));
}

void
gst_v4l2_mpeg4_enc_register (GstPlugin * plugin, const gchar * basename,
    const gchar * device_path, GstCaps * sink_caps, GstCaps * src_caps)
{
  gst_v4l2_video_enc_register (plugin, GST_TYPE_V4L2_MPEG4_ENC,
      "mpeg4", basename, device_path, sink_caps,
      gst_static_caps_get (&src_template_caps), src_caps);
}