/* Complete NE program entry sequence for TDKPIN.EXE. */

#include "tdkpin_program_entry.h"

#include "tdkpin_application.h"
#include "tdkpin_borland_runtime.h"
#include "tdkpin_initialization.h"
#include "tdkpin_multimedia.h"
#include "tdkpin_stack.h"
#include "tdkpin_tpwincrt_lifecycle.h"

enum {
    DGROUP_APPLICATION_VMT = 0x0024,
    DGROUP_VERSION_ERROR_TEXT = 0x0396,
    DGROUP_APPLICATION_TITLE = 0x03c8,
    DGROUP_APPLICATION_NAME = 0x03e1,
    DGROUP_APPLICATION_OBJECT = 0x0748,
    APPLICATION_RUN_SLOT = 0x1c,
    APPLICATION_DESTRUCTOR_SLOT = 0x08,
    WIN16_MB_ICONHAND = 0x0010,
};

static bool windows_version_is_supported(uint32_t version)
{
    uint8_t major = (uint8_t)version;
    uint8_t minor = (uint8_t)(version >> 8);
    return major > 3 || (major == 3 && minor >= 10);
}

/*
 * 1000:fd85 -- process entry named by the NE header.  InitTask supplies the
 * register contract consumed by 1020:0002.  Unit initializers run in the exact
 * image order before the independent Windows 3.10 gate.  The application Run
 * and destructor calls remain indirect through VMT +1c and +08 respectively.
 * Both the unsupported-version path and normal application return Halt(0).
 */
_Noreturn void tdkpin_ne_program_entry(void)
{
    BorlandWin16StartupRegisters registers = InitTask16();
    borland_initialize_win16_runtime(&registers);
    tdkpin_initialize_stack_guard();
    tpwincrt_initialize_runtime_unit();
    multimedia_initialize_runtime_unit();
    tdkpin_initialize_unit_ordinal_91();
    tdkpin_initialize_unit_ordinal_86();
    tdkpin_initialize_unit_ordinal_72();

    g_tdkpin_windows_version = GetVersion16();
    if (!windows_version_is_supported(g_tdkpin_windows_version)) {
        (void)win16_call_message_box_far(
            g_win16_message_box,
            0,
            win16_dgroup_pointer(DGROUP_VERSION_ERROR_TEXT),
            win16_dgroup_pointer(DGROUP_APPLICATION_TITLE),
            WIN16_MB_ICONHAND);
    } else {
        Win16FarPtr application =
            win16_dgroup_pointer(DGROUP_APPLICATION_OBJECT);
        (void)object_windows_application_construct(
            application,
            DGROUP_APPLICATION_VMT,
            win16_dgroup_pointer(DGROUP_APPLICATION_NAME));

        uint16_t vmt_offset = win16_read_u16(application);
        Win16FarPtr vmt = win16_dgroup_pointer(vmt_offset);
        win16_call_object_method(
            win16_read_far_pointer(vmt, APPLICATION_RUN_SLOT),
            application);
        win16_call_object_destructor(
            win16_read_far_pointer(vmt, APPLICATION_DESTRUCTOR_SLOT),
            application,
            0);
    }

    borland_runtime_exit(0);
}