#include "../tdkpin_dispatch.h"

#include <assert.h>
#include <setjmp.h>

static jmp_buf g_error_jump;
static uint16_t g_error_code;
static Win16FarPtr g_dispatched_procedure;
static Win16FarPtr g_receiver;
static Win16FarPtr g_argument;

_Noreturn void borland_runtime_error(uint16_t code)
{
    g_error_code = code;
    longjmp(g_error_jump, 1);
}

void win16_call_dynamic_method(Win16FarPtr procedure)
{
    g_dispatched_procedure = procedure;
}

void win16_call_dynamic_method_two_far(
    Win16FarPtr procedure, Win16FarPtr receiver, Win16FarPtr argument)
{
    g_dispatched_procedure = procedure;
    g_receiver = receiver;
    g_argument = argument;
}

static void write_far(uint16_t offset, Win16FarPtr pointer)
{
    win16_write_u16(
        win16_dgroup_pointer(offset), 0, win16_far_offset(pointer));
    win16_write_u16(
        win16_dgroup_pointer((uint16_t)(offset + 2)),
        0,
        win16_far_selector(pointer));
}

int main(void)
{
    static uint8_t dgroup[0x1000];
    static uint8_t object[32];
    win16_reset_segment_bindings();
    win16_bind_segment(0x5000, dgroup, sizeof(dgroup), true);
    win16_set_dgroup_selector(0x5000);
    win16_bind_segment(0x6000, object, sizeof(object), true);

    /* VMT 0x0100 -> derived dynamic table 0x0200. */
    win16_write_u16(win16_dgroup_pointer(0x0104), 0, 0x0200);
    win16_write_u16(win16_dgroup_pointer(0x0200), 0, 0x0300);
    win16_write_u16(win16_dgroup_pointer(0x0202), 0, 0xffff);
    win16_write_u16(win16_dgroup_pointer(0x0204), 0, 0xffff);
    win16_write_u16(win16_dgroup_pointer(0x0206), 0, 2);
    win16_write_u16(win16_dgroup_pointer(0x0208), 0, 10);
    win16_write_u16(win16_dgroup_pointer(0x020a), 0, 20);
    write_far(0x020c, win16_make_far_pointer(0x7000, 0x1111));
    write_far(0x0210, win16_make_far_pointer(0x7000, 0x2222));

    win16_write_u16(win16_dgroup_pointer(0x0300), 0, 0);
    win16_write_u16(win16_dgroup_pointer(0x0302), 0, 0xffff);
    win16_write_u16(win16_dgroup_pointer(0x0304), 0, 0xffff);
    win16_write_u16(win16_dgroup_pointer(0x0306), 0, 1);
    win16_write_u16(win16_dgroup_pointer(0x0308), 0, 30);
    write_far(0x030a, win16_make_far_pointer(0x7100, 0x3333));

    Win16FarPtr slot = borland_resolve_dynamic_method_slot(0x0100, 20);
    assert(slot == win16_dgroup_pointer(0x0210));
    assert(win16_read_u16(win16_dgroup_pointer(0x0202)) == 20);
    assert(win16_read_u16(win16_dgroup_pointer(0x0204)) == 0x0210);

    /* The cache bypasses the now-corrupted method-count word. */
    win16_write_u16(win16_dgroup_pointer(0x0206), 0, 0xffff);
    assert(borland_find_dynamic_method(0x0100, 20) == slot);
    win16_write_u16(win16_dgroup_pointer(0x0206), 0, 2);

    slot = borland_resolve_dynamic_method_slot(0x0100, 30);
    assert(slot == win16_dgroup_pointer(0x030a));
    assert(win16_read_u16(win16_dgroup_pointer(0x0302)) == 30);
    assert(win16_read_u16(win16_dgroup_pointer(0x0304)) == 0x030a);

    g_dispatched_procedure = 0;
    borland_dispatch_dynamic_method(0x0100, 10);
    assert(g_dispatched_procedure ==
           win16_make_far_pointer(0x7000, 0x1111));

    /* Generated callers use the receiver VMT and preserve both far args. */
    win16_write_u16(win16_dgroup_pointer(0x0404), 0, 0x0500);
    win16_write_u16(win16_dgroup_pointer(0x0500), 0, 0);
    win16_write_u16(win16_dgroup_pointer(0x0502), 0, 0xffff);
    win16_write_u16(win16_dgroup_pointer(0x0504), 0, 0xffff);
    win16_write_u16(win16_dgroup_pointer(0x0506), 0, 2);
    win16_write_u16(win16_dgroup_pointer(0x0508), 0, 0x8002);
    win16_write_u16(win16_dgroup_pointer(0x050a), 0, 0x0006);
    write_far(0x050c, win16_make_far_pointer(0x7200, 0x4444));
    write_far(0x0510, win16_make_far_pointer(0x7300, 0x5555));
    Win16FarPtr receiver = win16_make_far_pointer(0x6000, 4);
    Win16FarPtr argument = win16_make_far_pointer(0x6100, 0x1234);
    win16_write_u16(receiver, 0, 0x0400);

    borland_dispatch_method_8002(receiver, argument);
    assert(g_dispatched_procedure ==
           win16_make_far_pointer(0x7200, 0x4444));
    assert(g_receiver == receiver && g_argument == argument);
    borland_dispatch_method_0006(receiver, argument);
    assert(g_dispatched_procedure ==
           win16_make_far_pointer(0x7300, 0x5555));
    assert(g_receiver == receiver && g_argument == argument);

    if (setjmp(g_error_jump) == 0) {
        (void)borland_resolve_dynamic_method_slot(0x0100, 99);
        assert(false);
    }
    assert(g_error_code == 210);
    return 0;
}