/* ========================== *
 * Startup
 * ========================== */

typedef struct S_StartupReceipt S_StartupReceipt;
struct S_StartupReceipt { i32 _; };
S_StartupReceipt sprite_startup(void);

/* ========================== *
 * Tag
 * ========================== */

typedef struct S_Tag S_Tag;
struct S_Tag {
    u64 hash;
    String path;
};

INLINE S_Tag sprite_tag_nil(void) { return (S_Tag) { 0 }; }

S_Tag sprite_tag_from_path(String path);
b32 sprite_tag_is_nil(S_Tag tag);
b32 sprite_tag_eq(S_Tag t1, S_Tag t2);

/* ========================== *
 * Scope
 * ========================== */

typedef struct S_Scope S_Scope;
struct S_Scope {
    struct sprite_scope_cache_ref **ref_node_bins;
    struct sprite_scope_cache_ref *ref_node_pool;
    u64 num_references;
    S_Scope *next_free;
};

S_Scope *sprite_scope_begin(void);
void sprite_scope_end(S_Scope *scope);

/* ========================== *
 * Texture load
 * ========================== */

typedef struct S_Texture S_Texture;
struct S_Texture {
    b32 loaded;
    b32 valid;
    G_Resource *gp_texture;
    u32 width;
    u32 height;
};

S_Texture *sprite_texture_from_tag_await(S_Scope *scope, S_Tag tag);
S_Texture *sprite_texture_from_tag_async(S_Scope *scope, S_Tag tag);
void sprite_texture_from_tag_prefetch(S_Scope *scope, S_Tag tag);

/* ========================== *
 * Sheet load
 * ========================== */

typedef struct S_SheetSliceGroup S_SheetSliceGroup;
typedef struct S_SheetSpan S_SheetSpan;
typedef struct S_SheetFrame S_SheetFrame;
typedef struct S_Sheet S_Sheet;
struct S_Sheet {
    b32 loaded;
    b32 valid;
    V2 image_size;
    V2 frame_size;

    u32 frames_count;
    S_SheetFrame *frames;

    u32 spans_count;
    S_SheetSpan *spans;
    Dict *spans_dict;

    u32 slice_groups_count;
    S_SheetSliceGroup *slice_groups;
    Dict *slice_groups_dict;
};

S_Sheet *sprite_sheet_from_tag_await(S_Scope *scope, S_Tag tag);
S_Sheet *sprite_sheet_from_tag_async(S_Scope *scope, S_Tag tag);
void sprite_sheet_from_tag_prefetch(S_Scope *scope, S_Tag tag);

/* ========================== *
 * Sheet query
 * ========================== */

typedef struct S_SheetFrame S_SheetFrame;
struct S_SheetFrame {
    u32 index;
    f64 duration;
    ClipRect clip;
};

typedef struct S_SheetSpan S_SheetSpan;
struct S_SheetSpan {
    String name;
    u32 start;
    u32 end;
};

typedef struct S_SheetSlice S_SheetSlice;
struct S_SheetSlice {
    /* If 1, this slice was not copied over from another frame in the sprite sheet */
    b32 original;

    /* If 1, the slice has a corresponding '.ray' slice affecting the 'dir' fields */
    b32 has_ray;

    /* Values are in the range -0.5 (top / left edge) -> +0.5 (bottom / right edge) */
    Rect rect;
    V2 center;
    V2 dir;

    /* '_px' values retain the original sprite pixel dimensions */
    Rect rect_px;
    V2 center_px;
    V2 dir_px;
};

typedef struct S_SheetSliceArray S_SheetSliceArray;
struct S_SheetSliceArray {
    u64 count;
    S_SheetSlice *slices;
};

typedef struct S_SheetSliceGroup S_SheetSliceGroup;
struct S_SheetSliceGroup {
    String name;
    u64 per_frame_count;

    /* 2d array of slices with length (num frames) * (num slices per frame).
     * Index with [(frame index * num slices per frame) + slice index in frame] */
    S_SheetSlice *frame_slices;
};

S_SheetFrame sprite_sheet_get_frame(S_Sheet *sheet, u32 index);

S_SheetSpan sprite_sheet_get_span(S_Sheet *sheet, String name);

/* Returns first slice with name in frame */
S_SheetSlice sprite_sheet_get_slice(S_Sheet *sheet, String name, u32 frame_index);

/* Returns all slices with name in frame */
S_SheetSliceArray sprite_sheet_get_slices(S_Sheet *sheet, String name, u32 frame_index);