// M1.2 A.4b.i — '__sx_state' ivar registration on sx-defined
// '#objc_class'.
//
// Class-pair init now:
//   1. allocs the class pair
//   2. registers a single '__sx_state : *void' ivar
//   3. finalises the class
//   4. stores the runtime Ivar handle in a per-class global
//      ('__<ClassName>_state_ivar') so IMP trampolines can later
//      'object_getIvar' the state struct pointer.
//
// Round-trip below: after main starts, look up SxFoo, then ask
// the runtime if SxFoo has an Ivar named '__sx_state'. Returns
// non-null iff registration succeeded.
//
// IMP trampolines (A.4b.ii) and the '+alloc' / '-dealloc'
// overrides (A.5 / A.6) come next.

#import "modules/std.sx";
#import "modules/compiler.sx";
#import "modules/std/objc.sx";

class_getInstanceVariable :: (cls: *void, name: [*]u8) -> *void #foreign objc;

SxFoo :: #objc_class("SxFoo") {
    counter: s32;

    bump :: (self: *Self) {
        self.counter += 1;
    }
}

main :: () -> s32 {
    inline if OS == .macos {
        cls : Class = objc_getClass("SxFoo".ptr);
        if cls == null {
            print("FAIL: SxFoo not registered\n");
            return 1;
        }
        iv := class_getInstanceVariable(cls, "__sx_state".ptr);
        if iv == null {
            print("FAIL: __sx_state ivar missing\n");
            return 1;
        }
        print("ivar: __sx_state\n");
    }
    inline if OS != .macos {
        print("ivar: __sx_state\n");
    }
    0;
}