#include "prosperon.h"
#include "cell.h"

#include "HandmadeMath.h"

struct sprite{
  HMM_Vec2 pos; // x,y coordinates of the sprite
  HMM_Vec2 center;
  HMM_Vec2 skew;
  HMM_Vec2 scale;
  float rotation;
  HMM_Mat2 affine;
  JSValue image; // the JS image
  int layer; // layer this sprite draws onto
  HMM_Vec4 color; // color in 0-1f
};

typedef struct sprite sprite;

sprite *make_sprite(void)
{
  sprite *sprite = calloc(sizeof(*sprite),1);
  sprite->image = JS_NULL;
  return sprite;
}

void sprite_free(JSRuntime *rt, sprite *sprite)
{
  JS_FreeValueRT(rt,sprite->image);
  free(sprite);
}

void sprite_apply(sprite *sp)
{
  /* -------- rotation + skew → 2×2 affine matrix -------- */
  float  rot = sp->rotation;
  HMM_Vec2 k = sp->skew;

  float c = cosf(rot), s = sinf(rot);

  sp->affine.Columns[0] = (HMM_Vec2){ .x =  c + k.x * s,
                                      .y =  k.y * c + s };
  sp->affine.Columns[1] = (HMM_Vec2){ .x = -s + k.x * c,
                                      .y = -k.y * s + c };
}

// Sprite class definitions
static JSClassID js_sprite_id;
static void js_sprite_mark(JSRuntime *rt, JSValueConst val, JS_MarkFunc *mark_func) {
  sprite *sp = JS_GetOpaque(val, js_sprite_id);
  if (!sp) return;
  JS_MarkValue(rt, sp->image, mark_func);
}

// Class definition for sprite with mark function for GC
QJSCLASSMARK(sprite,)

// SPRITE GETTER/SETTER FUNCTIONS
JSC_GETSET(sprite, pos, vec2)
JSC_GETSET(sprite, center, vec2)
JSC_GETSET(sprite, layer, number)
JSC_GETSET(sprite, color, color)
JSC_GETSET(sprite, skew, vec2)
JSC_GETSET(sprite, scale, vec2)
JSC_GETSET(sprite, rotation, number)

// SPRITE ACTION FUNCTIONS

JSC_CCALL(sprite_move,
  sprite *sp = js2sprite(js,self);
  HMM_Vec2 mv = js2vec2(js,argv[0]);
  sp->pos.x += mv.x;
  sp->pos.y += mv.y;
)

JSC_CCALL(sprite_set_affine,
  sprite *sp = js2sprite(js,self);
  sprite_apply(sp);
)

JSC_CCALL(sprite_set_image,
  sprite *sp = js2sprite(js,self);
  if (!JS_IsNull(sp->image))
    JS_FreeValue(js,sp->image);
  sp->image = JS_DupValue(js, argv[0]);
)

static const JSCFunctionListEntry js_sprite_funcs[] = {
  MIST_FUNC_DEF(sprite, set_affine, 0),
  MIST_FUNC_DEF(sprite, set_image, 1),
  MIST_FUNC_DEF(sprite, move, 1),
  JS_CGETSET_DEF("pos", js_sprite_get_pos, js_sprite_set_pos),
  JS_CGETSET_DEF("scale", js_sprite_get_scale, js_sprite_set_scale),
  JS_CGETSET_DEF("skew", js_sprite_get_skew, js_sprite_set_skew),
  JS_CGETSET_DEF("layer", js_sprite_get_layer, js_sprite_set_layer),
  JS_CGETSET_DEF("color", js_sprite_get_color, js_sprite_set_color),
  JS_CGETSET_DEF("center", js_sprite_get_center, js_sprite_set_center),
  JS_CGETSET_DEF("rotation", js_sprite_get_rotation, js_sprite_set_rotation),
};

// Constructor function for sprite
static JSValue js_sprite_constructor(JSContext *js, JSValueConst new_target, int argc, JSValueConst *argv) {
  sprite *sp = make_sprite();
  if (!sp) return JS_ThrowOutOfMemory(js);
  
  // If an options object is provided, initialize the sprite with it
  if (argc > 0 && JS_IsObject(argv[0])) {
    JS_GETATOM(js, sp->pos, argv[0], pos, vec2)
    JS_GETATOM(js, sp->center, argv[0], center, vec2)
    JS_GETATOM(js, sp->skew, argv[0], skew, vec2)
    JS_GETATOM(js, sp->scale, argv[0], scale, vec2)
    JS_GETATOM(js, sp->rotation, argv[0], rotation, number)
    JS_GETATOM(js, sp->layer, argv[0], layer, number)
    JS_GETATOM(js, sp->color, argv[0], color, color)
    
    JSValue image = JS_GetProperty(js, argv[0], JS_NewAtom(js, "image"));
    if (!JS_IsNull(image)) {
      sp->image = image;  // Transfer ownership, no need to dup
    }
  }
  
  // Default values if not provided
  if (sp->scale.x == 0 && sp->scale.y == 0) {
    sp->scale.x = 1;
    sp->scale.y = 1;
  }
  if (sp->color.w == 0) sp->color.w = 1;  // Default alpha to 1
  
  sprite_apply(sp);
  return sprite2js(js, sp);
}

CELL_USE_INIT(
  // Register the sprite class
  QJSCLASSPREP_FUNCS(sprite);
  
  // Create the constructor function
  JSValue ctor = JS_NewCFunction2(js, js_sprite_constructor, "sprite", 1, JS_CFUNC_generic, 0);
  
  // Set the prototype on the constructor
  JSValue proto = JS_GetClassProto(js, js_sprite_id);
  JS_SetConstructor(js, ctor, proto);
  JS_FreeValue(js, proto);
  
  return ctor;
)