use cpp_oop::gen_oop;
use cpp_oop::CastPtr;

gen_oop! {
    #[default]
    struct Foo {
        foo: u32,
    }

    struct FooLayout {
        #[virt]
        foo: fn(this: &Self, a: i32) -> u32,
        #[virt]
        foo2: fn(this: &Self) -> u32,
    }

    impl FooMethodsInner for Foo {
        extern "C" fn foo_inner_virt(_this: &Self, _a: i32) -> u32 {
            1
        }

        extern "C" fn foo2_inner_virt(_this: &Self) -> u32 {
            2
        }
    }
}

gen_oop! {
    #[default]
    #[base(Foo)]
    struct Bar {
        bar: u32,
    }

    struct BarLayout {
        bar: fn(this: &mut Self) -> u32,
        bar2: fn(this: &Self) -> u32,
    }

    impl BarMethodsInner for Bar {
        extern "C" fn bar_inner(_this: &mut Self) -> u32 {
            3
        }

        extern "C" fn bar2_inner(_this: &Self) -> u32 {
            4
        }
    }

    impl FooMethodsInner for Bar {
        extern "C" fn foo_inner_virt(_this: &Self, _a: i32) -> u32 {
            10
        }

        #[unused]
        extern "C" fn foo2_inner_virt(_this: &Self) -> u32 {}
    }
}

gen_oop! {
    #[default]
    #[base(Bar)]
    struct Baz {
        baz: u32,
    }

    struct BazLayout {
        #[virt]
        baz: fn(this: &Self) -> u32,
    }

    impl BazMethodsInner for Baz {
        extern "C" fn baz_inner_virt(_this: &Self) -> u32 {
            5
        }
    }

    impl BarMethodsInner for Baz {
        extern "C" fn foo_inner_virt(_this: &Self, _a: i32) -> u32 {
            100
        }

        #[unused]
        extern "C" fn foo2_inner_virt(_this: &Self) -> u32 {}

        extern "C" fn bar_inner(_this: &mut Self) -> u32 {
            30
        }

        #[unused]
        extern "C" fn bar2_inner(_this: &Self) -> u32 {}
    }
}

#[test]
fn layout() {
    assert_eq!(std::mem::size_of::<Foo>(), std::mem::size_of::<usize>() * 2);
    assert_eq!(std::mem::size_of::<Bar>(), std::mem::size_of::<usize>() * 3);
    assert_eq!(std::mem::size_of::<Baz>(), std::mem::size_of::<usize>() * 4);
}

#[test]
fn basic() {
    let mut bz = Baz::default();
    let mut bz_ptr = &mut bz as *mut Baz;
    let mut b_ptr: *mut Bar = Bar::cast_mut(bz_ptr);
    let f_ptr: *const Foo = Foo::cast_const(b_ptr);

    assert_eq!(Foo::foo_inner_virt(&bz.base_bar.base_foo, 0), 1); // manual selection of the method to call
    assert_eq!(Bar::foo_inner_virt(&bz.base_bar, 0), 10); // manual selection of the method to call
    assert_eq!(Baz::foo_inner_virt(&bz, 0), 100); // manual selection of the method to call

    assert_eq!(Foo::foo2_inner_virt(&bz.base_bar.base_foo), 2); // manual selection of the method to call
                                                                // Bar::foo2_inner will give an error cuz its unused
                                                                // Baz::foo2_inner will give an error cuz its unused

    assert_eq!(Bar::bar_inner(&mut bz.base_bar), 3); // manual selection of the method to call
    assert_eq!(Baz::bar_inner(&mut bz), 30); // manual selection of the method to call

    assert_eq!(Bar::bar2_inner(&bz.base_bar), 4); // manual selection of the method to call
                                                  // Baz::bar2_inner will give an error cuz its unused

    assert_eq!(Baz::baz_inner_virt(&bz), 5); // manual selection of the method to call

    assert_eq!(bz.foo(0), 100); // static dispatch
    assert_eq!(bz.foo2(), 2); // static dispatch
    assert_eq!(bz.bar(), 30); // static dispatch
    assert_eq!(bz.bar2(), 4); // static dispatch
    assert_eq!(bz.baz(), 5); // static dispatch

    assert_eq!(f_ptr.foo(0), 100); // this one will use vtable
    assert_eq!(f_ptr.foo2(), 2); // this one will use vtable

    assert_eq!(b_ptr.foo(0), 100); // this one will use vtable
    assert_eq!(b_ptr.foo2(), 2); // this one will use vtable
    assert_eq!(b_ptr.bar(), 3); // this one is no virt so it will use static dispatch
    assert_eq!(b_ptr.bar2(), 4); // this one is no virt so it will use static dispatch

    assert_eq!(bz_ptr.foo(0), 100); // this one will use vtable
    assert_eq!(bz_ptr.foo2(), 2); // this one will use vtable
    assert_eq!(bz_ptr.bar(), 30); // this one is no virt so it will use static dispatch
    assert_eq!(bz_ptr.bar2(), 4); // this one is no virt so it will use static dispatch
    assert_eq!(bz_ptr.baz(), 5); // this one is no virt so it will use static dispatch
}