#pragma once

#include <stddef.h>

// #define offsetof(TYPE, MEMBER)          ((size_t) &((TYPE *)0)->MEMBER)
#define rb_container_of(ptr, type, member) (type *)((char *)(ptr) - offsetof(type,member));

#ifdef _WIN32
__declspec(align(8)) struct rb_node {
#else
struct rb_node {
#endif
    unsigned long   rb_parent_color;
    struct rb_node *rb_right;
    struct rb_node *rb_left;
#ifdef _WIN32
};
#else
} __attribute__((aligned(sizeof(long))));
#endif

struct rb_root {
    struct rb_node *rb_node;
};

#define	RB_RED		0
#define	RB_BLACK	1

#define rb_parent(r)    ((struct rb_node *)((r)->rb_parent_color & ~3))
#define rb_color(r)     ((r)->rb_parent_color & 1)
#define rb_is_red(r)    (!rb_color(r))
#define rb_is_black(r)  rb_color(r)
#define rb_set_red(r)   do { (r)->rb_parent_color &= ~1; } while (0)
#define rb_set_black(r) do { (r)->rb_parent_color |= 1; } while (0)

static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p) {
    rb->rb_parent_color = (rb->rb_parent_color & 3) | (unsigned long)p;
}

static inline void rb_set_color(struct rb_node *rb, int color) {
    rb->rb_parent_color = (rb->rb_parent_color & ~1) | color;
}

#define RB_ROOT	(struct rb_root)    { NULL }
#define	rb_entry(ptr, type, member) rb_container_of(ptr, type, member)

#define RB_IS_ROOT_EMPTY(root)  ((root)->rb_node == NULL)
#define RB_IS_NODE_EMPTY(node)  (rb_parent(node) == node)
#define RB_CLEAR_NODE(node)     (rb_set_parent(node, node))

static inline void rb_init_node(struct rb_node *rb) {
    rb->rb_parent_color = 0;
    rb->rb_right = NULL;
    rb->rb_left = NULL;
    RB_CLEAR_NODE(rb);
}

void rb_insert_color(struct rb_node *node, struct rb_root *root);
void rb_erase(struct rb_node *node, struct rb_root *root);

typedef void (*rb_augment_f)(struct rb_node *node, void *data);
void rb_augment_insert(struct rb_node *node, rb_augment_f func, void *data);
struct rb_node *rb_augment_erase_begin(struct rb_node *node);
void rb_augment_erase_end(struct rb_node *node, rb_augment_f func, void *data);

struct rb_node *rb_next(const struct rb_node *node);
struct rb_node *rb_prev(const struct rb_node *node);
struct rb_node *rb_first(const struct rb_root *root);
struct rb_node *rb_last(const struct rb_root *root);

/* Fast replacement of a single node without remove/rebalance/add/rebalance */
void rb_replace_node(struct rb_node *victim, struct rb_node *node, struct rb_root *root);

static inline void rb_link_node(struct rb_node *node, struct rb_node *parent, struct rb_node **rb_link) {
    node->rb_parent_color = (unsigned long )parent;
    node->rb_left = node->rb_right = NULL;
    *rb_link = node;
}