#ifndef _API_H
#define _API_H

#include <stdafx.h>
#include <vecmath.h>

typedef int Error;

#define ERROR_NONE 0
#define ERROR_OUT_OF_MEMORY 1
#define ERROR_OUT_OF_BLOCKS 2
#define ERROR_OUT_OF_MATERIALS 3
#define ERROR_OUT_OF_TEXTURES 4

typedef int Orientation;

#define ORIENTATION_NEGATIVE_X ~0
#define ORIENTATION_POSITIVE_X 0
#define ORIENTATION_NEGATIVE_Y ~1
#define ORIENTATION_POSITIVE_Y 1
#define ORIENTATION_NEGATIVE_Z ~2
#define ORIENTATION_POSITIVE_Z 2

#define ORIENTATION_INIT_SIGN_INDEX(sign, index) ((sign) > 0 ? (index) : ~(index))
#define ORIENTATION_GET_INDEX(orientation) ((orientation) & 0x4 ? ~(orientation) : (orientation))
#define ORIENTATION_GET_SIGN(orientation) ((oritentation) & 0x4 ? -1 : 1)

typedef int Transform;

#define TRANSFORM_IDENTITY 0
#define TRANSFORM_ROTATE_CW 1
#define TRANSFORM_ROTATE_CCW 2
#define TRANSFORM_ROTATE_180 3
#define TRANSFORM_MIRROR 4
#define TRANSFORM_MIRROR_ROTATE_CW 5
#define TRANSFORM_MIRROR_ROTATE_CCW 6
#define TRANSFORM_MIRROR_ROTATE_180 7

typedef unsigned short BlockId;

#define BLOCK_ID_AIR 0

typedef unsigned short MaterialId;

#define MATERIAL_ID_EMPTY 0

typedef unsigned short TextureId;

#define TEXTURE_ID_EMPTY_BASE_COLOR 0
#define TEXTURE_ID_EMPTY_EMISSIVE 1
#define TEXTURE_ID_EMPTY_NORMAL 2
#define TEXTURE_ID_EMPTY_OCCLUSION_ROUGHNESS_METALLIC 3

typedef int TextureUsage;

#define TEXTURE_USAGE_BASE_COLOR 0
#define TEXTURE_USAGE_NORMAL 1
#define TEXTURE_USAGE_OCCLUSION_ROUGHNESS_METALLIC 2
#define TEXTURE_USAGE_EMISSIVE 3

typedef struct String {
    const char* ptr;
    size_t len;
} String;

#define STRING_NULL (String){ .ptr = NULL, .len = 0 }

typedef struct BlockDefinitionWall {
    MaterialId material;
    Transform transform;
} BlockDefinitionWall;

typedef struct BlockDefinitionWalls {
    BlockDefinitionWall negative_x;
    BlockDefinitionWall positive_x;
    BlockDefinitionWall negative_y;
    BlockDefinitionWall positive_y;
    BlockDefinitionWall negative_z;
    BlockDefinitionWall positive_z;
} BlockDefinitionWalls;

typedef struct BlockDefinition {
    BlockDefinitionWalls walls;
} BlockDefinition;

typedef struct MaterialDefinition {
    vec3_t base_color;
    vec3_t emissive;
    float ior;
    float metallic;
    float normal_scale;
    float occlusion_texture_strength;
    float roughness;

    TextureId base_color_texture;
    TextureId emissive_texture;
    TextureId normal_texture;
    TextureId occlusion_roughness_metallic_texture;
} MaterialDefinition;

typedef struct TextureData {
    TextureUsage usage;
    unsigned int width;
    unsigned int height;
    const char *data;
} TextureData;

typedef struct TextureDataMutable {
    TextureUsage usage;
    unsigned int width;
    unsigned int height;
    char *data;
} TextureDataMutable;

Error BlockIdFromName(String name, bool *exists, BlockId *out);
Error BlockDefinitionFromId(BlockId id, const BlockDefinition **out);
Error BlockDefine(String name, const BlockDefinition *definition, BlockId *out);

Error MaterialIdFromName(String name, bool *exists, MaterialId *out);
Error MaterialDefinitionFromId(MaterialId, const MaterialDefinition **out);
Error MaterialDefine(String name, const MaterialDefinition *definition, MaterialId *out);

Error TextureIdFromName(String name, TextureUsage usage, bool *exists, TextureId *out);
Error TextureDefine(String name, const TextureData *texture_data, TextureId *out);

Error TextureResize(TextureDataMutable *texture_data, unsigned int width, unsigned int height);

// --- CALLBACKS ---

void PreInit();
void PostInit();
void Deinit();

void FilterBlock(BlockId id, String name, bool *exists, BlockDefinition *definition);
void FilterMaterial(MaterialId id, String name, bool *exists, MaterialDefinition *definition);
void FilterTexture(TextureId id, String name, bool *exists, TextureDataMutable *texture_data);

#endif