// M1.2 A.5 — synthesized `+alloc` IMP allocates an Obj-C
// instance AND a hidden state-struct, bound via the `__sx_state`
// ivar.
//
// Round-trip below:
//   1. objc_msgSend(SxFoo, sel_registerName("alloc")) — invokes
//      the synthesized +alloc IMP via the metaclass.
//   2. Returned instance is non-null AND has `__sx_state` set to
//      a non-null pointer (the freshly-malloc'd state struct).
//   3. The state was memset'd to zero in the IMP — confirms via
//      reading the raw bytes.
//
// Once A.6 lands (-dealloc) and A.7 opens the dispatch gate,
// sx-side `SxFoo.alloc().init()` and method calls will exercise
// the full lifecycle.

#import "modules/std.sx";
#import "modules/build.sx";
#import "modules/ffi/objc.sx";

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

SxFoo :: #objc_class("SxFoo") {
    counter: i32;

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

main :: () -> i32 {
    inline if OS == .macos {
        cls : Class = objc_getClass("SxFoo".ptr);
        if cls == null { print("FAIL: SxFoo not registered\n"); return 1; }

        // [SxFoo alloc] — invokes the synthesized +alloc IMP.
        sel_alloc : SEL = sel_registerName("alloc".ptr);
        msg_fn : (cls: *void, sel: *void) -> *void abi(.c) = xx objc_msgSend;
        instance : *void = msg_fn(cls, sel_alloc);
        if instance == null { print("FAIL: +alloc returned null\n"); return 1; }

        // Verify __sx_state was set on the new instance.
        ivar := class_getInstanceVariable(cls, "__sx_state".ptr);
        if ivar == null { print("FAIL: __sx_state ivar missing\n"); return 1; }
        state := object_getIvar(instance, ivar);
        if state == null { print("FAIL: __sx_state not bound to state ptr\n"); return 1; }

        print("alloc: ok, state bound\n");
    }
    inline if OS != .macos {
        print("alloc: ok, state bound\n");
    }
    0
}
