// ffi-objc-arc-00 — M4.0 end-to-end allocator threading regression.
//
// Verifies that the per-instance allocator design from M1.2 A.5 + M4.0
// is actually wired:
//   1. `push Context.{ allocator = xx tracker } { SxFoo.alloc(); }` →
//      the state struct is allocated via tracker (not libc).
//   2. The state struct's first field is `__sx_allocator` (captures the
//      tracker so -dealloc can free through it).
//   3. `f.release()` drives refcount → 0 → -dealloc fires → reads the
//      captured allocator → calls tracker.dealloc_bytes(state).
//   4. The alloc/dealloc deltas around the call pair balance to (+1, +1)
//      — exactly one sx-defined-class state struct round-trips.
//
// Pre-M4.0 the +alloc IMP used libc `malloc` and -dealloc used libc
// `free`, both bypassing context.allocator — tracker would have
// observed (+0, +0) deltas, missing the leak silently.
//
// Important: capture tracker counters BEFORE and AFTER the
// alloc/release with NOTHING else allocating in between. `print`
// allocates strings (NSString-backed), which would also route through
// tracker and pollute the deltas.

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

SxAllocProbe :: #objc_class("SxAllocProbe") {
    #extends NSObject;
    counter: i32;
    alloc :: () -> *SxAllocProbe;
}

main :: () -> i32 {
    inline if OS == .macos {
        gpa := GPA.init();
        tracker := TrackingAllocator.init(xx gpa);

        push Context.{ allocator = xx tracker, data = null } {
            // Snapshot BEFORE the sx-defined alloc.
            alloc_before   := tracker.alloc_count;
            dealloc_before := tracker.dealloc_count;

            f := SxAllocProbe.alloc();

            // Snapshot AFTER alloc, BEFORE release.
            alloc_after_alloc   := tracker.alloc_count;
            dealloc_after_alloc := tracker.dealloc_count;

            f.release();

            // Snapshot AFTER release.
            alloc_after_release   := tracker.alloc_count;
            dealloc_after_release := tracker.dealloc_count;

            // Verify deltas (do all asserts before any print).
            alloc_delta_a   := alloc_after_alloc   - alloc_before;
            dealloc_delta_a := dealloc_after_alloc - dealloc_before;
            alloc_delta_r   := alloc_after_release   - alloc_after_alloc;
            dealloc_delta_r := dealloc_after_release - dealloc_after_alloc;

            if alloc_delta_a < 1 {
                print("FAIL: alloc didn't fire through tracker; delta={}\n", alloc_delta_a);
                return 1;
            }
            if dealloc_delta_a != 0 {
                print("FAIL: dealloc fired prematurely; delta={}\n", dealloc_delta_a);
                return 1;
            }
            if dealloc_delta_r < 1 {
                print("FAIL: release→-dealloc didn't route through tracker; delta={}\n", dealloc_delta_r);
                return 1;
            }
            if dealloc_delta_r != alloc_delta_a {
                print("FAIL: alloc/dealloc deltas mismatched; alloc={} dealloc={}\n",
                      alloc_delta_a, dealloc_delta_r);
                return 1;
            }
        }

        print("allocator round-trip: ok\n");
    }
    inline if OS != .macos {
        print("skipped (not macos)\n");
    }
    0
}