#include "e.h"

/* FIXME: something is weird here - i had to reverse all stacking logic to make
 * it work... */

typedef struct _E_Smart_Data  E_Smart_Data;
typedef struct _E_Layout_Item E_Layout_Item;

struct _E_Smart_Data
{
   Evas_Coord    x, y, w, h;
   Evas_Coord    vw, vh;
   Evas_Object  *obj;
   Evas_Object  *clip;
   int           frozen;
   unsigned char changed E_BITFIELD;
   Eina_Inlist  *items;
};

struct _E_Layout_Item
{
   EINA_INLIST;
   E_Smart_Data *sd;
   Evas_Coord    x, y, w, h;
   Evas_Object  *obj;
};

/* local subsystem functions */
static E_Layout_Item *_e_layout_smart_adopt(E_Smart_Data *sd, Evas_Object *obj);
static void           _e_layout_smart_disown(Evas_Object *obj);
static void           _e_layout_smart_item_del_hook(void *data, Evas *e, Evas_Object *obj, void *event_info);
static void           _e_layout_smart_reconfigure(E_Smart_Data *sd);
static void           _e_layout_smart_move_resize_item(E_Layout_Item *li);

static void           _e_layout_smart_init(void);
static void           _e_layout_smart_add(Evas_Object *obj);
static void           _e_layout_smart_del(Evas_Object *obj);
static void           _e_layout_smart_move(Evas_Object *obj, Evas_Coord x, Evas_Coord y);
static void           _e_layout_smart_resize(Evas_Object *obj, Evas_Coord w, Evas_Coord h);
static void           _e_layout_smart_show(Evas_Object *obj);
static void           _e_layout_smart_hide(Evas_Object *obj);
static void           _e_layout_smart_color_set(Evas_Object *obj, int r, int g, int b, int a);
static void           _e_layout_smart_clip_set(Evas_Object *obj, Evas_Object *clip);
static void           _e_layout_smart_clip_unset(Evas_Object *obj);

/* local subsystem globals */
static Evas_Smart *_e_smart = NULL;

/* externally accessible functions */
E_API Evas_Object *
e_layout_add(Evas *evas)
{
   _e_layout_smart_init();
   return evas_object_smart_add(evas, _e_smart);
}

E_API int
e_layout_freeze(Evas_Object *obj)
{
   E_Smart_Data *sd;

   if (evas_object_smart_smart_get(obj) != _e_smart) SMARTERR(0);
   sd = evas_object_smart_data_get(obj);
   sd->frozen++;
   return sd->frozen;
}

E_API int
e_layout_thaw(Evas_Object *obj)
{
   E_Smart_Data *sd;

   if (evas_object_smart_smart_get(obj) != _e_smart) SMARTERR(0);
   sd = evas_object_smart_data_get(obj);
   sd->frozen--;
   if (sd->frozen <= 0) _e_layout_smart_reconfigure(sd);
   return sd->frozen;
}

E_API void
e_layout_virtual_size_set(Evas_Object *obj, Evas_Coord w, Evas_Coord h)
{
   E_Smart_Data *sd;

   if (evas_object_smart_smart_get(obj) != _e_smart) SMARTERRNR();
   sd = evas_object_smart_data_get(obj);
   if (w < 1) w = 1;
   if (h < 1) h = 1;
   if ((sd->vw == w) && (sd->vh == h)) return;
   sd->vw = w;
   sd->vh = h;
   sd->changed = 1;
   if (sd->frozen <= 0) _e_layout_smart_reconfigure(sd);
}

E_API void
e_layout_virtual_size_get(Evas_Object *obj, Evas_Coord *w, Evas_Coord *h)
{
   E_Smart_Data *sd;

   if (evas_object_smart_smart_get(obj) != _e_smart) SMARTERRNR();
   sd = evas_object_smart_data_get(obj);
   if (w) *w = sd->vw;
   if (h) *h = sd->vh;
}

E_API void
e_layout_coord_canvas_to_virtual(Evas_Object *obj, Evas_Coord cx, Evas_Coord cy, Evas_Coord *vx, Evas_Coord *vy)
{
   E_Smart_Data *sd;

   if (evas_object_smart_smart_get(obj) != _e_smart) SMARTERRNR();
   sd = evas_object_smart_data_get(obj);

   if (vx) *vx = (cx - sd->x) * ((double)(sd->vw) / sd->w);
   if (vy) *vy = (cy - sd->y) * ((double)(sd->vh) / sd->h);
}

E_API void
e_layout_coord_virtual_to_canvas(Evas_Object *obj, Evas_Coord vx, Evas_Coord vy, Evas_Coord *cx, Evas_Coord *cy)
{
   E_Smart_Data *sd;

   if (evas_object_smart_smart_get(obj) != _e_smart) SMARTERRNR();
   sd = evas_object_smart_data_get(obj);

   if (cx) *cx = vx * ((double)(sd->w) / sd->vw) + sd->x;
   if (cy) *cy = vy * ((double)(sd->h) / sd->vh) + sd->y;
}

E_API void
e_layout_pack(Evas_Object *obj, Evas_Object *child)
{
   E_Smart_Data *sd;
   E_Layout_Item *li;

   if (evas_object_smart_smart_get(obj) != _e_smart) SMARTERRNR();
   sd = evas_object_smart_data_get(obj);
   li = _e_layout_smart_adopt(sd, child);
   sd->items = eina_inlist_append(sd->items, EINA_INLIST_GET(li));
   evas_object_lower(child);
   if (sd->frozen <= 0) _e_layout_smart_move_resize_item(li);
}

E_API void
e_layout_child_move(Evas_Object *obj, Evas_Coord x, Evas_Coord y)
{
   E_Layout_Item *li;

   li = evas_object_data_get(obj, "e_layout_data");
   if (!li) return;
   if ((li->x == x) && (li->y == y)) return;
   li->x = x;
   li->y = y;
   if (li->sd->frozen <= 0) _e_layout_smart_move_resize_item(li);
}

E_API Evas_Object *
e_layout_child_above_get(Evas_Object *obj)
{
   E_Layout_Item *li;

   li = evas_object_data_get(obj, "e_layout_data");
   EINA_SAFETY_ON_NULL_RETURN_VAL(li, NULL);
   li = (E_Layout_Item*)EINA_INLIST_GET(li)->next;
   return li ? li->obj : NULL;
}

E_API Evas_Object *
e_layout_child_below_get(Evas_Object *obj)
{
   E_Layout_Item *li;

   li = evas_object_data_get(obj, "e_layout_data");
   EINA_SAFETY_ON_NULL_RETURN_VAL(li, NULL);
   li = (E_Layout_Item*)EINA_INLIST_GET(li)->prev;
   return li ? li->obj : NULL;
}

E_API Evas_Object *
e_layout_top_child_get(Evas_Object *obj)
{
   E_Smart_Data *sd;
   E_Layout_Item *li;

   if (evas_object_smart_smart_get(obj) != _e_smart) SMARTERRNR() NULL;
   sd = evas_object_smart_data_get(obj);
   if (!sd->items) return NULL;
   li = (E_Layout_Item*)sd->items->last;
   return li->obj;
}

E_API void
e_layout_child_resize(Evas_Object *obj, Evas_Coord w, Evas_Coord h)
{
   E_Layout_Item *li;

   li = evas_object_data_get(obj, "e_layout_data");
   if (!li) return;
   if (w < 0) w = 0;
   if (h < 0) h = 0;
   if ((li->w == w) && (li->h == h)) return;
   li->w = w;
   li->h = h;
   if (li->sd->frozen <= 0) _e_layout_smart_move_resize_item(li);
}

E_API void
e_layout_child_lower(Evas_Object *obj)
{
   E_Layout_Item *li;

   li = evas_object_data_get(obj, "e_layout_data");
   if (!li) return;
   if ((!li->sd->items) || (!EINA_INLIST_GET(li)->prev)) return;
   li->sd->items = eina_inlist_promote(li->sd->items, EINA_INLIST_GET(li));
   evas_object_lower(obj);
}

E_API void
e_layout_child_raise(Evas_Object *obj)
{
   E_Layout_Item *li;

   li = evas_object_data_get(obj, "e_layout_data");
   if (!li) return;
   if ((!li->sd->items) || (!EINA_INLIST_GET(li)->next)) return;
   li->sd->items = eina_inlist_demote(li->sd->items, EINA_INLIST_GET(li));
   evas_object_raise(obj);
}

E_API void
e_layout_child_lower_below(Evas_Object *obj, Evas_Object *below)
{
   E_Layout_Item *li, *li2;

   EINA_SAFETY_ON_NULL_RETURN(obj);
   EINA_SAFETY_ON_NULL_RETURN(below);
   if (obj == below) return;
   li = evas_object_data_get(obj, "e_layout_data");
   li2 = evas_object_data_get(below, "e_layout_data");
   if ((!li) || (!li2) || (li->sd != li2->sd)) return;
   li->sd->items = eina_inlist_remove(li->sd->items, EINA_INLIST_GET(li));
   evas_object_stack_below(obj, below);
   li->sd->items = eina_inlist_prepend_relative(li->sd->items, EINA_INLIST_GET(li), EINA_INLIST_GET(li2));
}

E_API void
e_layout_child_raise_above(Evas_Object *obj, Evas_Object *above)
{
   E_Layout_Item *li, *li2;

   EINA_SAFETY_ON_NULL_RETURN(obj);
   EINA_SAFETY_ON_NULL_RETURN(above);
   if (obj == above) return;
   li = evas_object_data_get(obj, "e_layout_data");
   li2 = evas_object_data_get(above, "e_layout_data");
   if ((!li) || (!li2) || (li->sd != li2->sd)) return;
   li->sd->items = eina_inlist_remove(li->sd->items, EINA_INLIST_GET(li));
   evas_object_stack_above(obj, above);
   li->sd->items = eina_inlist_append_relative(li->sd->items, EINA_INLIST_GET(li), EINA_INLIST_GET(li2));
}

E_API void
e_layout_child_geometry_get(Evas_Object *obj, Evas_Coord *x, Evas_Coord *y, Evas_Coord *w, Evas_Coord *h)
{
   E_Layout_Item *li;

   li = evas_object_data_get(obj, "e_layout_data");
   if (!li) return;

   if (x) *x = li->x;
   if (y) *y = li->y;
   if (w) *w = li->w;
   if (h) *h = li->h;
}

E_API void
e_layout_unpack(Evas_Object *obj)
{
   E_Layout_Item *li;
   E_Smart_Data *sd;

   li = evas_object_data_get(obj, "e_layout_data");
   if (!li) return;
   sd = li->sd;
   sd->items = eina_inlist_remove(sd->items, EINA_INLIST_GET(li));
   _e_layout_smart_disown(obj);
}

E_API Eina_List *
e_layout_children_get(Evas_Object *obj)
{
   E_Smart_Data *sd;
   Eina_List *l = NULL;
   E_Layout_Item *li;

   if (evas_object_smart_smart_get(obj) != _e_smart) SMARTERRNR() NULL;
   sd = evas_object_smart_data_get(obj);
   EINA_INLIST_FOREACH(sd->items, li)
     l = eina_list_append(l, li->obj);
   return l;
}

E_API Evas_Object *
e_layout_top_child_at_xy_get(Evas_Object *obj, Evas_Coord x, Evas_Coord y, Eina_Bool vis, const Eina_List *ignore)
{
   E_Smart_Data *sd;
   E_Layout_Item *li;

   if (evas_object_smart_smart_get(obj) != _e_smart) SMARTERRNR() NULL;
   sd = evas_object_smart_data_get(obj);
   if (!sd->items) return NULL;
   EINA_INLIST_REVERSE_FOREACH(sd->items, li)
     if (E_INSIDE(x, y, li->x, li->y, li->w, li->h))
       {
          if (eina_list_data_find(ignore, li->obj)) continue;
          if ((!vis) || evas_object_visible_get(li->obj))
            return li->obj;
       }
   return NULL;
}

/* local subsystem functions */
static E_Layout_Item *
_e_layout_smart_adopt(E_Smart_Data *sd, Evas_Object *obj)
{
   E_Layout_Item *li;

   li = evas_object_data_get(obj, "e_layout_data");
   if (li) e_layout_unpack(obj);
   li = calloc(1, sizeof(E_Layout_Item));
   if (!li) return NULL;
   li->sd = sd;
   li->obj = obj;
   /* defaults */
   li->x = 0;
   li->y = 0;
   li->w = 0;
   li->h = 0;
   evas_object_clip_set(obj, sd->clip);
   evas_object_smart_member_add(obj, li->sd->obj);
   evas_object_data_set(obj, "e_layout_data", li);
   evas_object_event_callback_add(obj, EVAS_CALLBACK_FREE,
                                  _e_layout_smart_item_del_hook, NULL);
   if ((!evas_object_visible_get(sd->clip)) &&
       (evas_object_visible_get(sd->obj)))
     evas_object_show(sd->clip);
   return li;
}

static void
_e_layout_smart_disown(Evas_Object *obj)
{
   E_Layout_Item *li;

   li = evas_object_data_get(obj, "e_layout_data");
   if (!li) return;
   if (!li->sd->items)
     {
        if (evas_object_visible_get(li->sd->clip))
          evas_object_hide(li->sd->clip);
     }
   evas_object_event_callback_del(obj,
                                  EVAS_CALLBACK_FREE,
                                  _e_layout_smart_item_del_hook);
   evas_object_smart_member_del(obj);
   evas_object_data_del(obj, "e_layout_data");
   free(li);
}

static void
_e_layout_smart_item_del_hook(void *data EINA_UNUSED, Evas *e EINA_UNUSED, Evas_Object *obj, void *event_info EINA_UNUSED)
{
   e_layout_unpack(obj);
}

static void
_e_layout_smart_reconfigure(E_Smart_Data *sd)
{
   E_Layout_Item *li;

   if (!sd->changed) return;

   EINA_INLIST_FOREACH(sd->items, li)
     _e_layout_smart_move_resize_item(li);
   sd->changed = 0;
}

static void
_e_layout_smart_move_resize_item(E_Layout_Item *li)
{
   evas_object_move(li->obj,
                    li->sd->x + ((li->x * li->sd->w) / li->sd->vw),
                    li->sd->y + ((li->y * li->sd->h) / li->sd->vh));
   evas_object_resize(li->obj,
                      MAX((li->w * li->sd->w) / li->sd->vw, 1),
                      MAX((li->h * li->sd->h) / li->sd->vh, 1));
}

static void
_e_layout_smart_init(void)
{
   if (_e_smart) return;
   {
      static const Evas_Smart_Class sc =
      {
         "e_layout",
         EVAS_SMART_CLASS_VERSION,
         _e_layout_smart_add,
         _e_layout_smart_del,
         _e_layout_smart_move,
         _e_layout_smart_resize,
         _e_layout_smart_show,
         _e_layout_smart_hide,
         _e_layout_smart_color_set,
         _e_layout_smart_clip_set,
         _e_layout_smart_clip_unset,
         NULL,
         NULL,
         NULL,
         NULL,
         NULL,
         NULL,
         NULL
      };
      _e_smart = evas_smart_class_new(&sc);
   }
}

static void
_e_layout_smart_add(Evas_Object *obj)
{
   E_Smart_Data *sd;

   sd = calloc(1, sizeof(E_Smart_Data));
   if (!sd) return;
   sd->obj = obj;
   sd->x = 0;
   sd->y = 0;
   sd->w = 0;
   sd->h = 0;
   sd->vw = 1;
   sd->vh = 1;
   sd->clip = evas_object_rectangle_add(evas_object_evas_get(obj));
   evas_object_smart_member_add(sd->clip, obj);
   evas_object_move(sd->clip, -100001, -100001);
   evas_object_resize(sd->clip, 200002, 200002);
   evas_object_color_set(sd->clip, 255, 255, 255, 255);
   evas_object_smart_data_set(obj, sd);
}

static void
_e_layout_smart_del(Evas_Object *obj)
{
   E_Smart_Data *sd;

   sd = evas_object_smart_data_get(obj);
   if (!sd) return;
   while (sd->items)
     {
        E_Layout_Item *li = (E_Layout_Item*)sd->items;
        sd->items = eina_inlist_remove(sd->items, EINA_INLIST_GET(li));
        _e_layout_smart_disown(li->obj);
     }
   evas_object_del(sd->clip);
   free(sd);
}

static void
_e_layout_smart_move(Evas_Object *obj, Evas_Coord x, Evas_Coord y)
{
   E_Smart_Data *sd;
   E_Layout_Item *li;
   Evas_Coord dx, dy;

   sd = evas_object_smart_data_get(obj);
   if (!sd) return;
   if ((x == sd->x) && (y == sd->y)) return;
   dx = x - sd->x;
   dy = y - sd->y;
   EINA_INLIST_FOREACH(sd->items, li)
     {
        Evas_Coord ox, oy;

        evas_object_geometry_get(li->obj, &ox, &oy, NULL, NULL);
        evas_object_move(li->obj, ox + dx, oy + dy);
     }
   sd->x = x;
   sd->y = y;
}

static void
_e_layout_smart_resize(Evas_Object *obj, Evas_Coord w, Evas_Coord h)
{
   E_Smart_Data *sd;

   sd = evas_object_smart_data_get(obj);
   if (!sd) return;
   if ((w == sd->w) && (h == sd->h)) return;
   sd->w = w;
   sd->h = h;
   sd->changed = 1;
   if (sd->frozen <= 0) _e_layout_smart_reconfigure(sd);
}

static void
_e_layout_smart_show(Evas_Object *obj)
{
   E_Smart_Data *sd;

   sd = evas_object_smart_data_get(obj);
   if (!sd) return;
   if (sd->items) evas_object_show(sd->clip);
}

static void
_e_layout_smart_hide(Evas_Object *obj)
{
   E_Smart_Data *sd;

   sd = evas_object_smart_data_get(obj);
   if (!sd) return;
   evas_object_hide(sd->clip);
}

static void
_e_layout_smart_color_set(Evas_Object *obj, int r, int g, int b, int a)
{
   E_Smart_Data *sd;

   sd = evas_object_smart_data_get(obj);
   if (!sd) return;
   evas_object_color_set(sd->clip, r, g, b, a);
}

static void
_e_layout_smart_clip_set(Evas_Object *obj, Evas_Object *clip)
{
   E_Smart_Data *sd;

   sd = evas_object_smart_data_get(obj);
   if (!sd) return;
   evas_object_clip_set(sd->clip, clip);
}

static void
_e_layout_smart_clip_unset(Evas_Object *obj)
{
   E_Smart_Data *sd;

   sd = evas_object_smart_data_get(obj);
   if (!sd) return;
   evas_object_clip_unset(sd->clip);
}