print INPUT_RECORD

main.cpp

#define NOMINMAX
#define WIN32_LEAN_AND_MEAN
#include <Windows.h>

#include <cstdio>

// wprintf() in the uCRT prints every single wchar_t individually and thus breaks surrogate
// pairs apart which Windows Terminal treats as invalid input and replaces it with U+FFFD.
static void printfUTF16(const _In_z_ _Printf_format_string_ wchar_t* const format, ...) {
    wchar_t buffer[512];

    va_list args;
    va_start(args, format);
    const auto length = _vsnwprintf_s(&buffer[0], 512, _TRUNCATE, format, args);
    va_end(args);

    WriteConsoleW(GetStdHandle(STD_OUTPUT_HANDLE), &buffer[0], length, nullptr, nullptr);
}

static wchar_t visualize(wchar_t ch) {
    if (ch < 0x20) {
        ch += 0x2400;
    } else if (ch == 0x20) {
        ch = 0x2423; // ␣
    } else if (ch == 0x7f) {
        ch = 0x2421; // ␡
    }
    return ch;
}

static void printInputRecord(const INPUT_RECORD& r) noexcept {
    switch (r.EventType) {
    case KEY_EVENT:
        printfUTF16(
            L"{\n"
            "    .EventType = KEY_EVENT,\n"
            "    .Event = {\n"
            "        .KeyEvent = {\n"
            "            .bKeyDown = %d,\n"
            "            .wRepeatCount = %d,\n"
            "            .wVirtualKeyCode = %d,\n"
            "            .wVirtualScanCode = %d,\n"
            "            .uChar.UnicodeChar = %04x, // %c\n"
            "            .dwControlKeyState = %d,\n"
            "        },\n"
            "    },\n"
            "}\n",
            r.Event.KeyEvent.bKeyDown,
            r.Event.KeyEvent.wRepeatCount,
            r.Event.KeyEvent.wVirtualKeyCode,
            r.Event.KeyEvent.wVirtualScanCode,
            r.Event.KeyEvent.uChar.UnicodeChar,
            visualize(r.Event.KeyEvent.uChar.UnicodeChar),
            r.Event.KeyEvent.dwControlKeyState
        );
        break;
    case MOUSE_EVENT:
        printfUTF16(
            L"{\n"
            "    .EventType = MOUSE_EVENT,\n"
            "    .Event = {\n"
            "        .MouseEvent = {\n"
            "            .dwMousePosition = { .X = %d, .Y = %d },\n"
            "            .dwButtonState = %d,\n"
            "            .dwControlKeyState = %d,\n"
            "            .dwEventFlags = %d,\n"
            "        },\n"
            "    },\n"
            "}\n",
            r.Event.MouseEvent.dwMousePosition.X,
            r.Event.MouseEvent.dwMousePosition.Y,
            r.Event.MouseEvent.dwButtonState,
            r.Event.MouseEvent.dwControlKeyState,
            r.Event.MouseEvent.dwEventFlags
        );
        break;
    case WINDOW_BUFFER_SIZE_EVENT:
        printfUTF16(
            L"{\n"
            "    .EventType = WINDOW_BUFFER_SIZE_EVENT,\n"
            "    .Event = {\n"
            "        .WindowBufferSizeEvent = {\n"
            "            .dwSize = { .X = %d, .Y = %d },\n"
            "        },\n"
            "    },\n"
            "}\n",
            r.Event.WindowBufferSizeEvent.dwSize.X,
            r.Event.WindowBufferSizeEvent.dwSize.Y
        );
        break;
    case MENU_EVENT:
        printfUTF16(
            L"{\n"
            "    .EventType = MENU_EVENT,\n"
            "    .Event = {\n"
            "        .MenuEvent = {\n"
            "            .dwCommandId = %d,\n"
            "        },\n"
            "    },\n"
            "}\n",
            r.Event.MenuEvent.dwCommandId
        );
        break;
    case FOCUS_EVENT:
        printfUTF16(
            L"{\n"
            "    .EventType = FOCUS_EVENT,\n"
            "    .Event = {\n"
            "        .FocusEvent = {\n"
            "            .bSetFocus = %d,\n"
            "        },\n"
            "    },\n"
            "}\n",
            r.Event.FocusEvent.bSetFocus
        );
        break;
    default:
        printfUTF16(
            L"{\n"
            "    .EventType = %d,\n"
            "    .Event = ?,\n"
            "}\n",
            r.EventType
        );
        break;
    }
}

int main() {
    for (;;) {
        INPUT_RECORD records[16];
        DWORD read = 0;

        if (!ReadConsoleInputW(GetStdHandle(STD_INPUT_HANDLE), &records[0], 16, &read) || !read) {
            break;
        }

        for (DWORD i = 0; i < read; ++i) {
            printInputRecord(records[i]);
        }
    }

    return 0;
}