#ifndef RAVA_GC_H
#define RAVA_GC_H

#include <stdint.h>
#include <stddef.h>
#include <stdbool.h>

#define RAVA_GC_BLOCK_SIZE      (32 * 1024)
#define RAVA_GC_LINE_SIZE       128
#define RAVA_GC_LINES_PER_BLOCK (RAVA_GC_BLOCK_SIZE / RAVA_GC_LINE_SIZE)

#define RAVA_GC_GRAY_STACK_SIZE 4096

#define RAVA_GC_INITIAL_THRESHOLD (1024 * 1024)

#define RAVA_ALIGN(size, align) (((size) + (align) - 1) & ~((align) - 1))

struct RavaGCHeader;
typedef struct RavaGCHeader RavaGCHeader_t;

typedef struct RavaGCBlock {
    uint8_t line_marks[RAVA_GC_LINES_PER_BLOCK];
    uint8_t flags;
    uint16_t free_lines;
    struct RavaGCBlock *next;
    struct RavaGCBlock *prev;
    uint8_t data[RAVA_GC_BLOCK_SIZE];
} RavaGCBlock_t;

#define RAVA_GC_BLOCK_FLAG_EVACUATE 0x01
#define RAVA_GC_BLOCK_FLAG_FULL     0x02

typedef struct RavaGCHeap {
    RavaGCBlock_t *all_blocks;
    RavaGCBlock_t *current_block;
    uint8_t *bump_ptr;
    uint8_t *block_limit;
    RavaGCBlock_t *free_blocks;
    RavaGCBlock_t *recyclable_blocks;
    size_t total_allocated;
    size_t live_bytes;
    size_t gc_threshold;
    RavaGCHeader_t *all_objects;
} RavaGCHeap_t;

typedef struct RavaGCStats {
    size_t total_collections;
    size_t objects_allocated;
    size_t objects_freed;
    size_t bytes_allocated;
    size_t bytes_freed;
    size_t current_live_objects;
    size_t current_live_bytes;
    size_t peak_live_bytes;
} RavaGCStats_t;

typedef struct RavaGCState {
    RavaGCHeader_t *gray_stack[RAVA_GC_GRAY_STACK_SIZE];
    size_t gray_count;
    bool gc_active;
    bool gc_enabled;
    size_t objects_marked;
    size_t bytes_marked;
} RavaGCState_t;

void rava_gc_init(void);
void rava_gc_shutdown(void);

void* rava_gc_alloc(size_t size, uint8_t type);
void rava_gc_free(void *ptr);

void rava_gc_collect(void);
void rava_gc_collect_if_needed(void);

void rava_gc_enable(void);
void rava_gc_disable(void);
bool rava_gc_is_enabled(void);

void rava_gc_pin(void *ptr);
void rava_gc_unpin(void *ptr);

RavaGCStats_t rava_gc_get_stats(void);
void rava_gc_print_stats(void);

#endif