/* Spa
 * Copyright (C) 2016 Wim Taymans <wim.taymans@gmail.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.
 */

#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <dlfcn.h>
#include <poll.h>
#include <pthread.h>
#include <errno.h>

#include <SDL2/SDL.h>

#include <spa/type-map.h>
#include <spa/log.h>
#include <spa/node.h>
#include <spa/loop.h>
#include <spa/video/format-utils.h>
#include <spa/format-builder.h>
#include <lib/debug.h>
#include <lib/props.h>
#include <lib/mapper.h>

typedef struct {
  uint32_t node;
  uint32_t props;
  uint32_t format;
  uint32_t props_device;
  uint32_t SDL_Texture;
  SpaTypeMeta meta;
  SpaTypeData data;
  SpaTypeMediaType media_type;
  SpaTypeMediaSubtype media_subtype;
  SpaTypeFormatVideo format_video;
  SpaTypeVideoFormat video_format;
  SpaTypeEventNode event_node;
  SpaTypeCommandNode command_node;
} Type;

static inline void
init_type (Type *type, SpaTypeMap *map)
{
  type->node = spa_type_map_get_id (map, SPA_TYPE__Node);
  type->props = spa_type_map_get_id (map, SPA_TYPE__Props);
  type->format = spa_type_map_get_id (map, SPA_TYPE__Format);
  type->props_device = spa_type_map_get_id (map, SPA_TYPE_PROPS__device);
  type->SDL_Texture = spa_type_map_get_id (map, SPA_TYPE_POINTER_BASE "SDL_Texture");
  spa_type_meta_map (map, &type->meta);
  spa_type_data_map (map, &type->data);
  spa_type_media_type_map (map, &type->media_type);
  spa_type_media_subtype_map (map, &type->media_subtype);
  spa_type_format_video_map (map, &type->format_video);
  spa_type_video_format_map (map, &type->video_format);
  spa_type_event_node_map (map, &type->event_node);
  spa_type_command_node_map (map, &type->command_node);
}

#define MAX_BUFFERS     8

typedef struct {
  SpaBuffer buffer;
  SpaMeta metas[2];
  SpaMetaHeader header;
  SpaMetaPointer ptr;
  SpaData datas[1];
  SpaChunk chunks[1];
} SDLBuffer;

typedef struct {
  Type type;

  SpaTypeMap *map;
  SpaLog *log;
  SpaLoop data_loop;

  SpaSupport support[4];
  uint32_t   n_support;

  SpaNode *source;
  SpaPortIO source_output[1];

  SDL_Renderer *renderer;
  SDL_Window *window;
  SDL_Texture *texture;

  bool use_buffer;

  bool running;
  pthread_t thread;

  SpaSource sources[16];
  unsigned int n_sources;

  bool rebuild_fds;
  struct pollfd fds[16];
  unsigned int n_fds;

  SpaBuffer *bp[MAX_BUFFERS];
  SDLBuffer buffers[MAX_BUFFERS];
  unsigned int n_buffers;
} AppData;

static SpaResult
make_node (AppData *data, SpaNode **node, const char *lib, const char *name)
{
  SpaHandle *handle;
  SpaResult res;
  void *hnd;
  SpaEnumHandleFactoryFunc enum_func;
  unsigned int i;
  uint32_t state = 0;

  if ((hnd = dlopen (lib, RTLD_NOW)) == NULL) {
    printf ("can't load %s: %s\n", lib, dlerror());
    return SPA_RESULT_ERROR;
  }
  if ((enum_func = dlsym (hnd, "spa_enum_handle_factory")) == NULL) {
    printf ("can't find enum function\n");
    return SPA_RESULT_ERROR;
  }

  for (i = 0; ;i++) {
    const SpaHandleFactory *factory;
    void *iface;

    if ((res = enum_func (&factory, state)) < 0) {
      if (res != SPA_RESULT_ENUM_END)
        printf ("can't enumerate factories: %d\n", res);
      break;
    }
    if (strcmp (factory->name, name))
      continue;

    handle = calloc (1, factory->size);
    if ((res = spa_handle_factory_init (factory, handle, NULL, data->support, data->n_support)) < 0) {
      printf ("can't make factory instance: %d\n", res);
      return res;
    }
    if ((res = spa_handle_get_interface (handle, data->type.node, &iface)) < 0) {
      printf ("can't get interface %d\n", res);
      return res;
    }
    *node = iface;
    return SPA_RESULT_OK;
  }
  return SPA_RESULT_ERROR;
}

static void
on_source_event (SpaNode *node, SpaEvent *event, void *user_data)
{
  AppData *data = user_data;

  if (SPA_EVENT_TYPE (event) == data->type.event_node.HaveOutput) {
    SpaResult res;
    SpaBuffer *b;
    void *sdata, *ddata;
    int sstride, dstride;
    int i;
    uint8_t *src, *dst;
    SpaMeta *metas;
    SpaData *datas;

    b = data->bp[data->source_output[0].buffer_id];

    metas = b->metas;
    datas = b->datas;

    if (metas[1].type == data->type.meta.Pointer &&
        ((SpaMetaPointer *)metas[1].data)->type == data->type.SDL_Texture) {
      SDL_Texture *texture;
      texture = ((SpaMetaPointer *)metas[1].data)->ptr;

      SDL_UnlockTexture(texture);

      SDL_RenderClear (data->renderer);
      SDL_RenderCopy (data->renderer, texture, NULL, NULL);
      SDL_RenderPresent (data->renderer);

      if (SDL_LockTexture (texture, NULL, &sdata, &sstride) < 0) {
        fprintf (stderr, "Couldn't lock texture: %s\n", SDL_GetError());
        return;
      }
      datas[0].type = data->type.data.MemPtr;
      datas[0].flags = 0;
      datas[0].fd = -1;
      datas[0].mapoffset = 0;
      datas[0].maxsize = sstride * 240;
      datas[0].data = sdata;
      datas[0].chunk->offset = 0;
      datas[0].chunk->size = sstride * 240;
      datas[0].chunk->stride = sstride;
    } else {
      if (SDL_LockTexture (data->texture, NULL, &ddata, &dstride) < 0) {
        fprintf (stderr, "Couldn't lock texture: %s\n", SDL_GetError());
        return;
      }
      sdata = datas[0].data;
      sstride = datas[0].chunk->stride;

      for (i = 0; i < 240; i++) {
        src = ((uint8_t*)sdata + i * sstride);
        dst = ((uint8_t*)ddata + i * dstride);
        memcpy (dst, src, SPA_MIN (sstride, dstride));
      }
      SDL_UnlockTexture(data->texture);

      SDL_RenderClear (data->renderer);
      SDL_RenderCopy (data->renderer, data->texture, NULL, NULL);
      SDL_RenderPresent (data->renderer);
    }

    if ((res = spa_node_process_output (data->source)) < 0)
      printf ("got pull error %d\n", res);
  }
  else {
    printf ("got event %d\n", SPA_EVENT_TYPE (event));
  }
}

static SpaResult
do_add_source (SpaLoop   *loop,
               SpaSource *source)
{
  AppData *data = SPA_CONTAINER_OF (loop, AppData, data_loop);

  data->sources[data->n_sources] = *source;
  data->n_sources++;
  data->rebuild_fds = true;

  return SPA_RESULT_OK;
}

static SpaResult
do_update_source (SpaSource  *source)
{
  return SPA_RESULT_OK;
}

static void
do_remove_source (SpaSource  *source)
{
}

static SpaResult
do_invoke (SpaLoop       *loop,
           SpaInvokeFunc  func,
           uint32_t       seq,
           size_t         size,
           void          *data,
           void          *user_data)
{
  return func (loop, false, seq, size, data, user_data);
}

static SpaResult
make_nodes (AppData *data, const char *device)
{
  SpaResult res;
  SpaProps *props;
  SpaPODBuilder b = { 0 };
  SpaPODFrame f[2];
  uint8_t buffer[256];

  if ((res = make_node (data, &data->source, "build/spa/plugins/v4l2/libspa-v4l2.so", "v4l2-source")) < 0) {
    printf ("can't create v4l2-source: %d\n", res);
    return res;
  }
  spa_node_set_event_callback (data->source, on_source_event, data);

  spa_pod_builder_init (&b, buffer, sizeof (buffer));
  spa_pod_builder_props (&b, &f[0], data->type.props,
      SPA_POD_PROP (&f[1], data->type.props_device, 0,
                           SPA_POD_TYPE_STRING, 1,
                           device ? device : "/dev/video0"));
  props = SPA_POD_BUILDER_DEREF (&b, f[0].ref, SpaProps);

  if ((res = spa_node_set_props (data->source, props)) < 0)
    printf ("got set_props error %d\n", res);

  return res;
}

static SpaResult
alloc_buffers (AppData *data)
{
  int i;

  for (i = 0; i < MAX_BUFFERS; i++) {
    SDLBuffer *b = &data->buffers[i];
    SDL_Texture *texture;
    void *ptr;
    int stride;

    data->bp[i] = &b->buffer;

    texture = SDL_CreateTexture (data->renderer,
                                 SDL_PIXELFORMAT_YUY2,
                                 SDL_TEXTUREACCESS_STREAMING,
                                 320, 240);
    if (!texture) {
      printf ("can't create texture: %s\n", SDL_GetError ());
      return SPA_RESULT_ERROR;
    }
    if (SDL_LockTexture (texture, NULL, &ptr, &stride) < 0) {
      fprintf (stderr, "Couldn't lock texture: %s\n", SDL_GetError());
      return SPA_RESULT_ERROR;
    }

    b->buffer.id = i;
    b->buffer.n_metas = 2;
    b->buffer.metas = b->metas;
    b->buffer.n_datas = 1;
    b->buffer.datas = b->datas;

    b->header.flags = 0;
    b->header.seq = 0;
    b->header.pts = 0;
    b->header.dts_offset = 0;
    b->metas[0].type = data->type.meta.Header;
    b->metas[0].data = &b->header;
    b->metas[0].size = sizeof (b->header);

    b->ptr.type = data->type.SDL_Texture;
    b->ptr.ptr = texture;
    b->metas[1].type = data->type.meta.Pointer;
    b->metas[1].data = &b->ptr;
    b->metas[1].size = sizeof (b->ptr);

    b->datas[0].type = data->type.data.MemPtr;
    b->datas[0].flags = 0;
    b->datas[0].fd = -1;
    b->datas[0].mapoffset = 0;
    b->datas[0].maxsize = stride * 240;
    b->datas[0].data = ptr;
    b->datas[0].chunk = &b->chunks[0];
    b->datas[0].chunk->offset = 0;
    b->datas[0].chunk->size = stride * 240;
    b->datas[0].chunk->stride = stride;
  }
  data->n_buffers = MAX_BUFFERS;

  return spa_node_port_use_buffers (data->source, SPA_DIRECTION_OUTPUT, 0, data->bp, data->n_buffers);
}

static SpaResult
negotiate_formats (AppData *data)
{
  SpaResult res;
  const SpaPortInfo *info;
  SpaFormat *format;
  SpaPODFrame f[2];
  uint8_t buffer[256];
  SpaPODBuilder b = SPA_POD_BUILDER_INIT (buffer, sizeof (buffer));

  if ((res = spa_node_port_set_io (data->source, SPA_DIRECTION_OUTPUT, 0, &data->source_output[0])) < 0)
    return res;

#if 0
  void *state = NULL;

  if ((res = spa_node_port_enum_formats (data->source, 0, &format, NULL, &state)) < 0)
    return res;
#else

  spa_pod_builder_format (&b, &f[0], data->type.format,
      data->type.media_type.video, data->type.media_subtype.raw,
      SPA_POD_PROP (&f[1], data->type.format_video.format, 0,
                           SPA_POD_TYPE_ID, 1,
                           data->type.video_format.YUY2),
      SPA_POD_PROP (&f[1], data->type.format_video.size, 0,
                           SPA_POD_TYPE_RECTANGLE, 1,
                           320, 240),
      SPA_POD_PROP (&f[1], data->type.format_video.framerate, 0,
                           SPA_POD_TYPE_FRACTION, 1,
                           25, 1));
  format = SPA_POD_BUILDER_DEREF (&b, f[0].ref, SpaFormat);
#endif

  if ((res = spa_node_port_set_format (data->source, SPA_DIRECTION_OUTPUT, 0, 0, format)) < 0)
    return res;

  if ((res = spa_node_port_get_info (data->source, SPA_DIRECTION_OUTPUT, 0, &info)) < 0)
    return res;

  if (data->use_buffer) {
    if ((res = alloc_buffers (data)) < 0)
      return res;
  } else {
    unsigned int n_buffers;

    data->texture = SDL_CreateTexture (data->renderer,
                                       SDL_PIXELFORMAT_YUY2,
                                       SDL_TEXTUREACCESS_STREAMING,
                                       320, 240);
    if (!data->texture) {
      printf ("can't create texture: %s\n", SDL_GetError ());
      return -1;
    }
    n_buffers = MAX_BUFFERS;
    if ((res = spa_node_port_alloc_buffers (data->source, SPA_DIRECTION_OUTPUT, 0, NULL, 0, data->bp, &n_buffers)) < 0) {
      printf ("can't allocate buffers: %s\n", SDL_GetError ());
      return -1;
    }
    data->n_buffers = n_buffers;
  }
  return SPA_RESULT_OK;
}

static void *
loop (void *user_data)
{
  AppData *data = user_data;

  printf ("enter thread\n");
  while (data->running) {
    int i, r;

    /* rebuild */
    if (data->rebuild_fds) {
      for (i = 0; i < data->n_sources; i++) {
        SpaSource *p = &data->sources[i];
        data->fds[i].fd = p->fd;
        data->fds[i].events = p->mask;
      }
      data->n_fds = data->n_sources;
      data->rebuild_fds = false;
    }

    r = poll ((struct pollfd *) data->fds, data->n_fds, -1);
    if (r < 0) {
      if (errno == EINTR)
        continue;
      break;
    }
    if (r == 0) {
      fprintf (stderr, "select timeout");
      break;
    }

    /* after */
    for (i = 0; i < data->n_sources; i++) {
      SpaSource *p = &data->sources[i];
      p->rmask = 0;
      if (data->fds[i].revents & POLLIN)
        p->rmask |= SPA_IO_IN;
      if (data->fds[i].revents & POLLOUT)
        p->rmask |= SPA_IO_OUT;
      if (data->fds[i].revents & POLLHUP)
        p->rmask |= SPA_IO_HUP;
      if (data->fds[i].revents & POLLERR)
        p->rmask |= SPA_IO_ERR;
    }
    for (i = 0; i < data->n_sources; i++) {
      SpaSource *p = &data->sources[i];
      if (p->rmask)
        p->func (p);
    }
  }
  printf ("leave thread\n");
  return NULL;
}

static void
run_async_source (AppData *data)
{
  SpaResult res;
  int err;

  {
    SpaCommand cmd = SPA_COMMAND_INIT (data->type.command_node.Start);
    if ((res = spa_node_send_command (data->source, &cmd)) < 0)
      printf ("got error %d\n", res);
  }

  data->running = true;
  if ((err = pthread_create (&data->thread, NULL, loop, data)) != 0) {
    printf ("can't create thread: %d %s", err, strerror (err));
    data->running = false;
  }

  sleep (10);

  if (data->running) {
    data->running = false;
    pthread_join (data->thread, NULL);
  }

  {
    SpaCommand cmd = SPA_COMMAND_INIT (data->type.command_node.Pause);
    if ((res = spa_node_send_command (data->source, &cmd)) < 0)
      printf ("got error %d\n", res);
  }
}

int
main (int argc, char *argv[])
{
  AppData data = { 0 };
  SpaResult res;

  data.use_buffer = true;

  data.map = spa_type_map_get_default ();
  data.log = spa_log_get_default ();

  data.data_loop.size = sizeof (SpaLoop);
  data.data_loop.add_source = do_add_source;
  data.data_loop.update_source = do_update_source;
  data.data_loop.remove_source = do_remove_source;
  data.data_loop.invoke = do_invoke;

  data.support[0].type = SPA_TYPE__TypeMap;
  data.support[0].data = data.map;
  data.support[1].type = SPA_TYPE__Log;
  data.support[1].data = data.log;
  data.support[2].type = SPA_TYPE_LOOP__DataLoop;
  data.support[2].data = &data.data_loop;
  data.support[3].type = SPA_TYPE_LOOP__MainLoop;
  data.support[3].data = &data.data_loop;
  data.n_support = 4;

  init_type (&data.type, data.map);

  if (SDL_Init (SDL_INIT_VIDEO) < 0) {
    printf ("can't initialize SDL: %s\n", SDL_GetError ());
    return -1;
  }

  if (SDL_CreateWindowAndRenderer (320, 240, SDL_WINDOW_RESIZABLE, &data.window, &data.renderer)) {
    printf ("can't create window: %s\n", SDL_GetError ());
    return -1;
  }


  if ((res = make_nodes (&data, argv[1])) < 0) {
    printf ("can't make nodes: %d\n", res);
    return -1;
  }
  if ((res = negotiate_formats (&data)) < 0) {
    printf ("can't negotiate nodes: %d\n", res);
    return -1;
  }

  run_async_source (&data);

  SDL_DestroyRenderer (data.renderer);

  return 0;
}