/* WirePlumber
 *
 * Copyright © 2020 Collabora Ltd.
 *    @author George Kiagiadakis <george.kiagiadakis@collabora.com>
 *
 * SPDX-License-Identifier: MIT
 */

#include <wp/wp.h>
#include <pipewire/pipewire.h>
#include <spa/debug/types.h>
#include <spa/param/audio/type-info.h>

#define SI_FACTORY_NAME "si-standard-link"

struct _WpSiStandardLink
{
  WpSessionItem parent;

  /* configuration */
  GWeakRef out_item;
  GWeakRef in_item;
  const gchar *out_item_port_context;
  const gchar *in_item_port_context;
  gboolean passive;

  /* activate */
  GPtrArray *node_links;
  guint n_async_ops_wait;
};

static void si_standard_link_link_init (WpSiLinkInterface * iface);

G_DECLARE_FINAL_TYPE (WpSiStandardLink, si_standard_link, WP, SI_STANDARD_LINK,
    WpSessionItem)
G_DEFINE_TYPE_WITH_CODE (WpSiStandardLink, si_standard_link,
    WP_TYPE_SESSION_ITEM,
    G_IMPLEMENT_INTERFACE (WP_TYPE_SI_LINK, si_standard_link_link_init))

static void
si_standard_link_init (WpSiStandardLink * self)
{
  g_weak_ref_init (&self->out_item, NULL);
  g_weak_ref_init (&self->in_item, NULL);
}

static void
si_standard_link_reset (WpSessionItem * item)
{
  WpSiStandardLink *self = WP_SI_STANDARD_LINK (item);

  /* deactivate first */
  wp_object_deactivate (WP_OBJECT (self),
      WP_SESSION_ITEM_FEATURE_ACTIVE | WP_SESSION_ITEM_FEATURE_EXPORTED);

  /* reset */
  g_weak_ref_set (&self->out_item, NULL);
  g_weak_ref_set (&self->in_item, NULL);
  self->out_item_port_context = NULL;
  self->in_item_port_context = NULL;
  self->passive = FALSE;

  WP_SESSION_ITEM_CLASS (si_standard_link_parent_class)->reset (item);
}

static WpSessionItem *
get_and_validate_item (WpProperties * props, const gchar *key)
{
  WpSessionItem *res = NULL;
  const gchar *str = NULL;

  str = wp_properties_get (props, key);
  if (!str || sscanf(str, "%p", &res) != 1 || !WP_IS_SI_LINKABLE (res) ||
      !(wp_object_get_active_features (WP_OBJECT (res)) &
          WP_SESSION_ITEM_FEATURE_ACTIVE))
    return NULL;

  return res;
}

static gboolean
si_standard_link_configure (WpSessionItem * item, WpProperties * p)
{
  WpSiStandardLink *self = WP_SI_STANDARD_LINK (item);
  g_autoptr (WpProperties) si_props = wp_properties_ensure_unique_owner (p);
  WpSessionItem *out_item, *in_item;
  const gchar *str;

  /* reset previous config */
  si_standard_link_reset (item);

  out_item = get_and_validate_item (si_props, "out.item");
  if (!out_item)
    return FALSE;
  wp_properties_setf (si_props, "out.item.id", "%u",
      wp_session_item_get_id (out_item));

  in_item = get_and_validate_item (si_props, "in.item");
  if (!in_item)
    return FALSE;
  wp_properties_setf (si_props, "in.item.id", "%u",
      wp_session_item_get_id (in_item));

  self->out_item_port_context = wp_properties_get (si_props,
      "out.item.port.context");

  self->in_item_port_context = wp_properties_get (si_props,
      "in.item.port.context");

  str = wp_properties_get (si_props, "passive");
  if (str && sscanf(str, "%u", &self->passive) != 1)
    return FALSE;
  if (!str)
    wp_properties_setf (si_props, "passive", "%u",
        self->passive);

  g_weak_ref_set(&self->out_item, out_item);
  g_weak_ref_set(&self->in_item, in_item);

  wp_properties_set (si_props, "si.factory.name", SI_FACTORY_NAME);
  wp_session_item_set_properties (WP_SESSION_ITEM (self),
      g_steal_pointer (&si_props));
  return TRUE;
}

static gpointer
si_standard_link_get_associated_proxy (WpSessionItem * item, GType proxy_type)
{
  return NULL;
}

static void
si_standard_link_disable_active (WpSessionItem *si)
{
  WpSiStandardLink *self = WP_SI_STANDARD_LINK (si);
  g_autoptr (WpSessionItem) si_out = g_weak_ref_get (&self->out_item);
  g_autoptr (WpSessionItem) si_in = g_weak_ref_get (&self->in_item);
  WpSiAcquisition *out_acquisition, *in_acquisition;

  if (si_out) {
    out_acquisition = wp_si_linkable_get_acquisition (
        WP_SI_LINKABLE (si_out));
    if (out_acquisition)
      wp_si_acquisition_release (out_acquisition, WP_SI_LINK (self),
          WP_SI_LINKABLE (si_out));
  }
  if (si_in) {
    in_acquisition = wp_si_linkable_get_acquisition (WP_SI_LINKABLE (si_in));
    if (in_acquisition)
      wp_si_acquisition_release (in_acquisition, WP_SI_LINK (self),
          WP_SI_LINKABLE (si_in));
  }

  g_clear_pointer (&self->node_links, g_ptr_array_unref);
  self->n_async_ops_wait = 0;

  wp_object_update_features (WP_OBJECT (self), 0,
      WP_SESSION_ITEM_FEATURE_ACTIVE);
}

static void
on_link_activated (WpObject * proxy, GAsyncResult * res,
    WpTransition * transition)
{
  WpSiStandardLink *self = wp_transition_get_source_object (transition);
  g_autoptr (GError) error = NULL;

  if (!wp_object_activate_finish (proxy, res, &error)) {
    wp_transition_return_error (transition, g_steal_pointer (&error));
    return;
  }

  self->n_async_ops_wait--;
  if (self->n_async_ops_wait == 0)
    wp_object_update_features (WP_OBJECT (self),
        WP_SESSION_ITEM_FEATURE_ACTIVE, 0);
}

static gboolean
create_links (WpSiStandardLink * self, WpTransition * transition,
    GVariant * out_ports, GVariant * in_ports, gboolean link_all)
{
  g_autoptr (GPtrArray) in_ports_arr = NULL;
  g_autoptr (WpCore) core = NULL;
  GVariantIter *iter = NULL;
  GVariant *child;
  guint32 out_node_id, in_node_id;
  guint32 out_port_id, in_port_id;
  guint32 out_channel, in_channel;
  guint i;

  /* tuple format:
      uint32 node_id;
      uint32 port_id;
      uint32 channel;  // enum spa_audio_channel
   */
  if (!out_ports || !g_variant_is_of_type (out_ports, G_VARIANT_TYPE("a(uuu)")))
    return FALSE;
  if (!in_ports || !g_variant_is_of_type (in_ports, G_VARIANT_TYPE("a(uuu)")))
    return FALSE;

  core = wp_object_get_core (WP_OBJECT (self));
  g_return_val_if_fail (core, FALSE);

  self->n_async_ops_wait = 0;
  self->node_links = g_ptr_array_new_with_free_func (g_object_unref);

  /* transfer the in ports to an array so that we can
     delete them when they are linked */
  i = g_variant_n_children (in_ports);
  in_ports_arr = g_ptr_array_new_full (i, (GDestroyNotify) g_variant_unref);
  g_ptr_array_set_size (in_ports_arr, i);

  g_variant_get (in_ports, "a(uuu)", &iter);
  while ((child = g_variant_iter_next_value (iter))) {
    g_ptr_array_index (in_ports_arr, --i) = child;
  }
  g_variant_iter_free (iter);

  /* now loop over the out ports and figure out where they should be linked */
  g_variant_get (out_ports, "a(uuu)", &iter);

  while (g_variant_iter_loop (iter, "(uuu)", &out_node_id, &out_port_id,
              &out_channel))
  {
    for (i = in_ports_arr->len; i > 0; i--) {
      child = g_ptr_array_index (in_ports_arr, i - 1);
      g_variant_get (child, "(uuu)", &in_node_id, &in_port_id, &in_channel);

      /* the channel has to match, unless we don't have any information
         on channel ordering on either side */
      if (link_all ||
          out_channel == in_channel ||
          out_channel == SPA_AUDIO_CHANNEL_UNKNOWN ||
          in_channel == SPA_AUDIO_CHANNEL_UNKNOWN ||
          in_channel == SPA_AUDIO_CHANNEL_MONO)
      {
        g_autoptr (WpProperties) props = NULL;
        WpLink *link;

        /* Create the properties */
        props = wp_properties_new_empty ();
        wp_properties_setf (props, PW_KEY_LINK_OUTPUT_NODE, "%u", out_node_id);
        wp_properties_setf (props, PW_KEY_LINK_OUTPUT_PORT, "%u", out_port_id);
        wp_properties_setf (props, PW_KEY_LINK_INPUT_NODE, "%u", in_node_id);
        wp_properties_setf (props, PW_KEY_LINK_INPUT_PORT, "%u", in_port_id);
        if (self->passive)
          wp_properties_set (props, PW_KEY_LINK_PASSIVE, "true");

        wp_debug_object (self, "create pw link: %u:%u (%s) -> %u:%u (%s)",
            out_node_id, out_port_id,
            spa_debug_type_find_name (spa_type_audio_channel, out_channel),
            in_node_id, in_port_id,
            spa_debug_type_find_name (spa_type_audio_channel, in_channel));

        /* create the link */
        link = wp_link_new_from_factory (core, "link-factory",
            g_steal_pointer (&props));
        g_ptr_array_add (self->node_links, link);

        /* activate to ensure it is created without errors */
        self->n_async_ops_wait++;
        wp_object_activate (WP_OBJECT (link),
            WP_PIPEWIRE_OBJECT_FEATURES_MINIMAL, NULL,
            (GAsyncReadyCallback) on_link_activated, transition);

        /* continue to link all input ports, if requested */
        if (link_all)
          continue;

        /* remove the linked input port from the array */
        g_ptr_array_remove_index (in_ports_arr, i - 1);

        /* break out of the for loop; go for the next out port */
        break;
      }
    }
  }
  g_variant_iter_free (iter);
  return self->node_links->len > 0;
}

static void
get_ports_and_create_links (WpSiStandardLink *self, WpTransition *transition)
{
  g_autoptr (WpSiLinkable) si_out = NULL;
  g_autoptr (WpSiLinkable) si_in = NULL;
  g_autoptr (GVariant) out_ports = NULL;
  g_autoptr (GVariant) in_ports = NULL;

  si_out = WP_SI_LINKABLE (g_weak_ref_get (&self->out_item));
  si_in = WP_SI_LINKABLE (g_weak_ref_get (&self->in_item));

  g_return_if_fail (si_out);
  g_return_if_fail (si_in);

  out_ports = wp_si_linkable_get_ports (si_out, self->out_item_port_context);
  in_ports = wp_si_linkable_get_ports (si_in, self->in_item_port_context);

  if (!create_links (self, transition, out_ports, in_ports, FALSE))
      wp_transition_return_error (transition, g_error_new (WP_DOMAIN_LIBRARY,
          WP_LIBRARY_ERROR_INVARIANT,
          "Failed to create links because of wrong ports"));
}

static void
on_adapters_ready (GObject *obj, GAsyncResult * res, gpointer p)
{
  WpTransition *transition = p;
  WpSiStandardLink *self = wp_transition_get_source_object (transition);
  g_autoptr (GError) error = NULL;

  wp_si_adapter_set_ports_format_finish (WP_SI_ADAPTER (obj), res, &error);
  if (error) {
    wp_transition_return_error (transition, g_steal_pointer (&error));
    return;
  }

  /* create links */
  get_ports_and_create_links (self, transition);
}

static void
on_out_adapter_ready (GObject *obj, GAsyncResult * res, gpointer p)
{
  WpTransition *transition = p;
  WpSiStandardLink *self = wp_transition_get_source_object (transition);
  g_autoptr (GError) error = NULL;
  g_autoptr (WpSiAdapter) si_out = NULL;
  g_autoptr (WpSiAdapter) si_in = NULL;
  g_autoptr (WpSpaPod) format = NULL;
  const gchar *mode = NULL;

  wp_si_adapter_set_ports_format_finish (WP_SI_ADAPTER (obj), res, &error);
  if (error) {
    wp_transition_return_error (transition, g_steal_pointer (&error));
    return;
  }

  si_out = WP_SI_ADAPTER (g_weak_ref_get (&self->out_item));
  si_in = WP_SI_ADAPTER (g_weak_ref_get (&self->in_item));

  g_return_if_fail (si_out);
  g_return_if_fail (si_in);

  /* Get out-format and set in-format */
  format = wp_si_adapter_get_ports_format (si_out, &mode);
  g_return_if_fail (mode);
  g_return_if_fail (format);
  wp_si_adapter_set_ports_format (si_in, wp_spa_pod_ref (format), mode,
      on_adapters_ready, transition);
}

static void
configure_and_link_adapters (WpSiStandardLink *self,
    WpTransition *transition)
{
  g_autoptr (WpSiAdapter) si_out = NULL;
  g_autoptr (WpSiAdapter) si_in = NULL;
  gboolean out_is_device = FALSE;
  gboolean in_is_device = FALSE;
  gboolean in_dont_remix = FALSE;
  gboolean out_dont_remix = FALSE;
  const gchar *str = NULL;

  si_out = WP_SI_ADAPTER (g_weak_ref_get (&self->out_item));
  si_in = WP_SI_ADAPTER (g_weak_ref_get (&self->in_item));

  g_return_if_fail (si_out);
  g_return_if_fail (si_in);

  str = wp_session_item_get_property (WP_SESSION_ITEM (si_out), "is.device");
  out_is_device = str && pw_properties_parse_bool (str);
  str = wp_session_item_get_property (WP_SESSION_ITEM (si_in), "is.device");
  in_is_device = str && pw_properties_parse_bool (str);

  str = wp_session_item_get_property (WP_SESSION_ITEM (si_out), "si.factory.name");
  out_is_device = (str && !g_strcmp0 (str, "si-audio-endpoint") && !in_is_device)
      || out_is_device;
  str = wp_session_item_get_property (WP_SESSION_ITEM (si_in), "si.factory.name");
  in_is_device = (str && !g_strcmp0 (str, "si-audio-endpoint") && !out_is_device)
      || in_is_device;

  str = wp_session_item_get_property (WP_SESSION_ITEM (si_out), "dont.remix");
  out_dont_remix = str && pw_properties_parse_bool (str);
  str = wp_session_item_get_property (WP_SESSION_ITEM (si_in), "dont.remix");
  in_dont_remix = str && pw_properties_parse_bool (str);

  wp_debug_object (self, "out [device:%d, dont_remix %d], "
      "in: [device %d, dont_remix %d]",
      out_is_device, out_dont_remix,
      in_is_device, in_dont_remix);

  /* Out is device node, In is not */
  if (out_is_device && !in_is_device) {
    const gchar *out_mode = NULL;
    g_autoptr (WpSpaPod) out_format =
        wp_si_adapter_get_ports_format (si_out, &out_mode);
    g_autoptr (WpSpaPod) in_format =
        wp_si_adapter_get_ports_format (si_in, NULL);
    g_return_if_fail (out_mode);
    g_return_if_fail (out_format);
    if (in_dont_remix || (in_format && wp_spa_pod_equal (out_format, in_format)))
      get_ports_and_create_links (self, transition);
    else
      wp_si_adapter_set_ports_format (si_in, wp_spa_pod_ref (out_format),
          out_mode, on_adapters_ready, transition);
  }

  /* Out is not device node, In is */
  else if (!out_is_device && in_is_device) {
    const gchar *in_mode = NULL;
    g_autoptr (WpSpaPod) in_format =
        wp_si_adapter_get_ports_format (si_in, &in_mode);
    g_autoptr (WpSpaPod) out_format =
        wp_si_adapter_get_ports_format (si_out, NULL);
    g_return_if_fail (in_format);
    g_return_if_fail (in_mode);
    if (out_dont_remix || (out_format && wp_spa_pod_equal (in_format, out_format)))
      get_ports_and_create_links (self, transition);
    else
      wp_si_adapter_set_ports_format (si_out, wp_spa_pod_ref (in_format),
          in_mode, on_adapters_ready, transition);
  }

  /* Both Out and In are device nodes */
  else if (out_is_device && in_is_device) {
    const gchar *out_mode = NULL;
    g_autoptr (WpSpaPod) out_format =
        wp_si_adapter_get_ports_format (si_out, &out_mode);
    g_autoptr (WpSpaPod) in_format =
        wp_si_adapter_get_ports_format (si_out, NULL);
    g_return_if_fail (out_mode);
    g_return_if_fail (out_format);
    g_return_if_fail (in_format);
    if (wp_spa_pod_equal (out_format, in_format))
      get_ports_and_create_links (self, transition);
    else
      wp_si_adapter_set_ports_format (si_in, wp_spa_pod_ref (out_format),
          out_mode, on_adapters_ready, transition);
  }

  /* Neither Out or In are device nodes */
  else if (!out_is_device && !in_is_device) {
    const gchar *mode = NULL;
    g_autoptr (WpSpaPod) out_format = wp_si_adapter_get_ports_format (si_out,
        &mode);
    if (out_format) {
      wp_si_adapter_set_ports_format (si_in, wp_spa_pod_ref (out_format), mode,
          on_adapters_ready, transition);
    } else {
      g_autoptr (WpSpaPod) in_format = wp_si_adapter_get_ports_format (si_in,
          &mode);
      if (in_format) {
        wp_si_adapter_set_ports_format (si_out, wp_spa_pod_ref (in_format),
            mode, on_adapters_ready, transition);
      } else {
        /* Use default format */
        wp_si_adapter_set_ports_format (si_out, NULL, NULL,
            on_out_adapter_ready, transition);
      }
    }
  }
}

static void
si_standard_link_do_link (WpSiStandardLink *self, WpTransition *transition)
{
  g_autoptr (WpSessionItem) si_out = g_weak_ref_get (&self->out_item);
  g_autoptr (WpSessionItem) si_in = g_weak_ref_get (&self->in_item);

  if (WP_IS_SI_ADAPTER (si_out) && WP_IS_SI_ADAPTER (si_in))
    configure_and_link_adapters (self, transition);
  else if (!WP_IS_SI_ADAPTER (si_out) && !WP_IS_SI_ADAPTER (si_in))
    get_ports_and_create_links (self, transition);
  else
    wp_transition_return_error (transition, g_error_new (WP_DOMAIN_LIBRARY,
          WP_LIBRARY_ERROR_INVARIANT,
          "Adapters cannot be linked with non-adapters"));
}

static void
on_item_acquired (WpSiAcquisition * acq, GAsyncResult * res,
    WpTransition * transition)
{
  WpSiStandardLink *self = wp_transition_get_source_object (transition);
  g_autoptr (GError) error = NULL;

  if (!wp_si_acquisition_acquire_finish (acq, res, &error)) {
    wp_transition_return_error (transition, g_steal_pointer (&error));
    return;
  }

  self->n_async_ops_wait--;
  if (self->n_async_ops_wait == 0)
    si_standard_link_do_link (self, transition);
}

static void
si_standard_link_enable_active (WpSessionItem *si, WpTransition *transition)
{
  WpSiStandardLink *self = WP_SI_STANDARD_LINK (si);
  g_autoptr (WpSessionItem) si_out = NULL;
  g_autoptr (WpSessionItem) si_in = NULL;
  WpSiAcquisition *out_acquisition = NULL, *in_acquisition = NULL;

  if (!wp_session_item_is_configured (si)) {
    wp_transition_return_error (transition,
        g_error_new (WP_DOMAIN_LIBRARY, WP_LIBRARY_ERROR_INVARIANT,
            "si-standard-link: item is not configured"));
    return;
  }

  /* make sure in/out items are valid */
  si_out = g_weak_ref_get (&self->out_item);
  si_in = g_weak_ref_get (&self->in_item);
  if (!si_out || !si_in) {
    wp_transition_return_error (transition,
        g_error_new (WP_DOMAIN_LIBRARY, WP_LIBRARY_ERROR_INVARIANT,
            "si-standard-link: in/out items are not valid anymore"));
    return;
  }

  /* acquire */
  out_acquisition = wp_si_linkable_get_acquisition (WP_SI_LINKABLE (si_out));
  in_acquisition = wp_si_linkable_get_acquisition (WP_SI_LINKABLE (si_in));
  if (out_acquisition && in_acquisition)
    self->n_async_ops_wait = 2;
  else if (out_acquisition || in_acquisition)
    self->n_async_ops_wait = 1;
  else {
    self->n_async_ops_wait = 0;
    si_standard_link_do_link (self, transition);
    return;
  }

  if (out_acquisition) {
    wp_si_acquisition_acquire (out_acquisition, WP_SI_LINK (self),
        WP_SI_LINKABLE (si_out), (GAsyncReadyCallback) on_item_acquired,
        transition);
  }
  if (in_acquisition) {
    wp_si_acquisition_acquire (in_acquisition, WP_SI_LINK (self),
        WP_SI_LINKABLE (si_in), (GAsyncReadyCallback) on_item_acquired,
        transition);
  }
}

static void
si_standard_link_finalize (GObject * object)
{
  WpSiStandardLink *self = WP_SI_STANDARD_LINK (object);

  g_weak_ref_clear (&self->out_item);
  g_weak_ref_clear (&self->in_item);

  G_OBJECT_CLASS (si_standard_link_parent_class)->finalize (object);
}

static void
si_standard_link_class_init (WpSiStandardLinkClass * klass)
{
  GObjectClass *object_class = (GObjectClass *) klass;
  WpSessionItemClass *si_class = (WpSessionItemClass *) klass;

  object_class->finalize = si_standard_link_finalize;

  si_class->reset = si_standard_link_reset;
  si_class->configure = si_standard_link_configure;
  si_class->get_associated_proxy = si_standard_link_get_associated_proxy;
  si_class->disable_active = si_standard_link_disable_active;
  si_class->enable_active = si_standard_link_enable_active;
}

static GVariant *
si_standard_link_get_registration_info (WpSiLink * item)
{
  GVariantBuilder b;
  g_variant_builder_init (&b, G_VARIANT_TYPE ("a{ss}"));
  return g_variant_builder_end (&b);
}

static WpSiLinkable *
si_standard_link_get_out_item (WpSiLink * item)
{
  WpSiStandardLink *self = WP_SI_STANDARD_LINK (item);
  return WP_SI_LINKABLE (g_weak_ref_get (&self->out_item));
}

static WpSiLinkable *
si_standard_link_get_in_item (WpSiLink * item)
{
  WpSiStandardLink *self = WP_SI_STANDARD_LINK (item);
  return WP_SI_LINKABLE (g_weak_ref_get (&self->in_item));
}

static void
si_standard_link_link_init (WpSiLinkInterface * iface)
{
  iface->get_registration_info = si_standard_link_get_registration_info;
  iface->get_out_item = si_standard_link_get_out_item;
  iface->get_in_item = si_standard_link_get_in_item;
}

WP_PLUGIN_EXPORT gboolean
wireplumber__module_init (WpCore * core, GVariant * args, GError ** error)
{
  wp_si_factory_register (core, wp_si_factory_new_simple (SI_FACTORY_NAME,
      si_standard_link_get_type ()));
  return TRUE;
}