#define _POSIX_C_SOURCE 200112L
#include <stdlib.h>
#include <assert.h>
#include "node.h"

static void destroy_notify(struct wl_listener *listener, void *data)
{
    struct diyac_node_descriptor *node_descriptor =
        wl_container_of(listener, node_descriptor, destroy);
    wl_list_remove(&node_descriptor->destroy.link);
    free(node_descriptor);
}

void diyac_node_descriptor_create(struct wlr_scene_node *scene_node, enum diyac_node_descriptor_type type, void *data)
{
    struct diyac_node_descriptor *node_descriptor = calloc(1, sizeof(*node_descriptor));
    node_descriptor->type = type;
    node_descriptor->data = data;
    node_descriptor->destroy.notify = destroy_notify;
    wl_signal_add(&scene_node->events.destroy, &node_descriptor->destroy);
    scene_node->data = node_descriptor;
}

struct diyac_layer_surface *diyac_layer_surface_from_node(struct wlr_scene_node *wlr_scene_node)
{
    assert(wlr_scene_node->data);
    struct diyac_node_descriptor *node_descriptor = wlr_scene_node->data;
    assert(node_descriptor->type == DIYAC_NODE_LAYER_SURFACE);
    return (struct diyac_layer_surface *)node_descriptor->data;
}
struct diyac_view *diyac_view_from_node(struct wlr_scene_node *wlr_scene_node)
{
    assert(wlr_scene_node->data);
    struct diyac_node_descriptor *node_descriptor = wlr_scene_node->data;
    assert(node_descriptor->type == DIYAC_NODE_VIEW || node_descriptor->type == DIYAC_NODE_XDG_POPUP);
    return (struct diyac_view *)node_descriptor->data;
}

struct diyac_node_descriptor * diyac_node_at(struct diyac_server* server, double lx, double ly, struct wlr_surface **surface, double *sx, double *sy)
{
    /* This returns the topmost node in the scene at the given layout coords.
     * We only care about surface nodes as we are specifically looking for a
     * surface in the surface tree of a diyac_view. */
    struct wlr_scene_node *node = wlr_scene_node_at(
        &server->scene->tree.node, lx, ly, sx, sy);
    if (node == NULL || node->type != WLR_SCENE_NODE_BUFFER)
    {
        return NULL;
    }
    struct wlr_scene_buffer *scene_buffer = wlr_scene_buffer_from_node(node);
    struct wlr_scene_surface *scene_surface =
        wlr_scene_surface_try_from_buffer(scene_buffer);
    if (!scene_surface)
    {
        return NULL;
    }

    *surface = scene_surface->surface;
    /* Find the node corresponding to the diyac_view at the root of this
     * surface tree, it is the only one for which we set the data field. */
    struct wlr_scene_tree *tree = node->parent;
    while (tree != NULL && tree->node.data == NULL)
    {
        tree = tree->node.parent;
    }
    return tree->node.data;
}