#ifndef STATE_H
#define STATE_H

#include "twn_game_api.h"


#define POINTS_PER_METER 128
#define UNDO_STACK_SIZE 32
#define CAMERA_FOV ((float)M_PI_2 * 0.75f)

#define POINT_LIMIT 65534
#define FACE_LIMIT 2048
#define OBJECT_LIMIT 16
#define TEXTURE_LIMIT 32

#define INVALID_POINT (POINT_LIMIT+1)
#define INVALID_FACE (FACE_LIMIT+1)
#define INVALID_OBJECT (OBJECT_LIMIT+1)
#define INVALID_TEXTURE (TEXTURE_LIMIT+1)

#define CAMERA_ROTATION_SPEED 0.04f
#define CAMERA_TRANSLATION_SPEED 0.04f
#define SELECTION_SPHERE_RADIUS 32
/* should be an odd number */
#define SNAP_LINES_SHOW 7
#define SNAP_LINES_WIDTH 1.0f
#define SNAP_LINES_COLOR ((Color){200,200,200,150})

typedef struct Operation {
    enum {
        OPERATION_MOVE_POINT,
        OPERATION_SET_TEXTURE,
        OPERATION_TRIANGULATE,
    } kind;
    union {
        struct {
            uint16_t point;
            int16_t delta_x;
            int16_t delta_y;
            int16_t delta_z;
            uint8_t object;
        } move_point;

        struct {
            uint16_t face;
            int16_t delta_texture;
            uint8_t object;
        } set_texture;

        struct {
            uint16_t old_face;
            uint16_t new_face;
            uint8_t object;
        } triangulate;
    } data;

    bool chained;
} Operation;

typedef struct Point {
    int16_t x, y, z;
} Point;

/* TODO: store topology in terms on edge connections? might be bad, as it's stateful */
/* triangles have p3 = INVALID_POINT */
/* lines have p2, p3 = INVALID_POINT */
/* billboards have p1, p2, p3 = INVALID_POINT */
typedef struct Face {
    uint16_t p[4];
    /* texture origin, as point on face plane, in absolute coordinates */
    int16_t tex_x, tex_y;
    uint8_t texture;
    uint8_t tex_scale;
} Face;

typedef struct Object {
    char *name;
    bool is_invisible;
    Point position;
    char *textures[TEXTURE_LIMIT + 1];
    uint8_t textures_sz;
    Point rotation;
    Face faces[FACE_LIMIT];
    uint16_t faces_sz;
} Object;

typedef struct State {
    Operation op_stack[UNDO_STACK_SIZE];
    uint32_t op_stack_ptr;
    bool op_active;

    Vec3 active_center;
    Vec3 camera_position;
    Vec3 camera_direction;
    float camera_zoom;
    bool camera_is_orthographic;
    /* defaults to wireframe */
    bool solid_display_mode;
    /* positions skipped */
    uint8_t grid_snap_granularity;

    Point points[POINT_LIMIT];
    uint16_t points_sz;

    Object objects[OBJECT_LIMIT];
    uint8_t objects_sz;

    /* which axes are blocked and which are not */
    /* order: x, y, z */
    bool axis_mask[3];
    char *current_texture;

    uint8_t current_hovered_obj;
    uint16_t current_hovered_face;
} State;


#endif