/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to

 * deal in the Software without restriction, including without limitation the

 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or

 * sell copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS

 * IN THE SOFTWARE.

 */

#include <assert.h>

#include <io.h>

#include <string.h>

#include <stdlib.h>

#if defined(_MSC_VER) && _MSC_VER < 1600

# include "uv/stdint-msvc2008.h"

#else

# include <stdint.h>

#endif

#ifndef COMMON_LVB_REVERSE_VIDEO

# define COMMON_LVB_REVERSE_VIDEO 0x4000

#endif

#include "uv.h"

#include "internal.h"

#include "handle-inl.h"

#include "stream-inl.h"

#include "req-inl.h"

#ifndef InterlockedOr

# define InterlockedOr _InterlockedOr

#endif

#define UNICODE_REPLACEMENT_CHARACTER (0xfffd)

#define ANSI_NORMAL           0x0000

#define ANSI_ESCAPE_SEEN      0x0002

#define ANSI_CSI              0x0004

#define ANSI_ST_CONTROL       0x0008

#define ANSI_IGNORE           0x0010

#define ANSI_IN_ARG           0x0020

#define ANSI_IN_STRING        0x0040

#define ANSI_BACKSLASH_SEEN   0x0080

#define ANSI_EXTENSION        0x0100

#define ANSI_DECSCUSR         0x0200

#define MAX_INPUT_BUFFER_LENGTH 8192

#define MAX_CONSOLE_CHAR 8192

#ifndef ENABLE_VIRTUAL_TERMINAL_PROCESSING

#define ENABLE_VIRTUAL_TERMINAL_PROCESSING 0x0004

#endif

#define CURSOR_SIZE_SMALL     25

#define CURSOR_SIZE_LARGE     100

static void uv_tty_capture_initial_style(

    CONSOLE_SCREEN_BUFFER_INFO* screen_buffer_info,

    CONSOLE_CURSOR_INFO* cursor_info);

static void uv_tty_update_virtual_window(CONSOLE_SCREEN_BUFFER_INFO* info);

static int uv__cancel_read_console(uv_tty_t* handle);

/* Null uv_buf_t */

static const uv_buf_t uv_null_buf_ = { 0, NULL };

enum uv__read_console_status_e {

  NOT_STARTED,

  IN_PROGRESS,

  TRAP_REQUESTED,

  COMPLETED

};

static volatile LONG uv__read_console_status = NOT_STARTED;

static volatile LONG uv__restore_screen_state;

static CONSOLE_SCREEN_BUFFER_INFO uv__saved_screen_state;

/*

 * The console virtual window.

 *

 * Normally cursor movement in windows is relative to the console screen buffer,

 * e.g. the application is allowed to overwrite the 'history'. This is very

 * inconvenient, it makes absolute cursor movement pretty useless. There is

 * also the concept of 'client rect' which is defined by the actual size of

 * the console window and the scroll position of the screen buffer, but it's

 * very volatile because it changes when the user scrolls.

 *

 * To make cursor movement behave sensibly we define a virtual window to which

 * cursor movement is confined. The virtual window is always as wide as the

 * console screen buffer, but it's height is defined by the size of the

 * console window. The top of the virtual window aligns with the position

 * of the caret when the first stdout/err handle is created, unless that would

 * mean that it would extend beyond the bottom of the screen buffer -  in that

 * that case it's located as far down as possible.

 *

 * When the user writes a long text or many newlines, such that the output

 * reaches beyond the bottom of the virtual window, the virtual window is

 * shifted downwards, but not resized.

 *

 * Since all tty i/o happens on the same console, this window is shared

 * between all stdout/stderr handles.

 */

static int uv_tty_virtual_offset = -1;

static int uv_tty_virtual_height = -1;

static int uv_tty_virtual_width = -1;

/* The console window size

 * We keep this separate from uv_tty_virtual_*. We use those values to only

 * handle signalling SIGWINCH

 */

static HANDLE uv__tty_console_handle = INVALID_HANDLE_VALUE;

static int uv__tty_console_height = -1;

static int uv__tty_console_width = -1;

static HANDLE uv__tty_console_resized = INVALID_HANDLE_VALUE;

static uv_mutex_t uv__tty_console_resize_mutex;

static DWORD WINAPI uv__tty_console_resize_message_loop_thread(void* param);

static void CALLBACK uv__tty_console_resize_event(HWINEVENTHOOK hWinEventHook,

                                                  DWORD event,

                                                  HWND hwnd,

                                                  LONG idObject,

                                                  LONG idChild,

                                                  DWORD dwEventThread,

                                                  DWORD dwmsEventTime);

static DWORD WINAPI uv__tty_console_resize_watcher_thread(void* param);

static void uv__tty_console_signal_resize(void);

/* We use a semaphore rather than a mutex or critical section because in some

   cases (uv__cancel_read_console) we need take the lock in the main thread and

   release it in another thread. Using a semaphore ensures that in such

   scenario the main thread will still block when trying to acquire the lock. */

static uv_sem_t uv_tty_output_lock;

static WORD uv_tty_default_text_attributes =

    FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE;

static char uv_tty_default_fg_color = 7;

static char uv_tty_default_bg_color = 0;

static char uv_tty_default_fg_bright = 0;

static char uv_tty_default_bg_bright = 0;

static char uv_tty_default_inverse = 0;

static CONSOLE_CURSOR_INFO uv_tty_default_cursor_info;

/* Determine whether or not ANSI support is enabled. */

static BOOL uv__need_check_vterm_state = TRUE;

static uv_tty_vtermstate_t uv__vterm_state = UV_TTY_UNSUPPORTED;

static void uv__determine_vterm_state(HANDLE handle);

void uv_console_init(void) {

  if (uv_sem_init(&uv_tty_output_lock, 1))

    abort();

  uv__tty_console_handle = CreateFileW(L"CONOUT$",

                                       GENERIC_READ | GENERIC_WRITE,

                                       FILE_SHARE_WRITE,

                                       0,

                                       OPEN_EXISTING,

                                       0,

                                       0);

  if (uv__tty_console_handle != INVALID_HANDLE_VALUE) {

    CONSOLE_SCREEN_BUFFER_INFO sb_info;

    QueueUserWorkItem(uv__tty_console_resize_message_loop_thread,

                      NULL,

                      WT_EXECUTELONGFUNCTION);

    uv_mutex_init(&uv__tty_console_resize_mutex);

    if (GetConsoleScreenBufferInfo(uv__tty_console_handle, &sb_info)) {

      uv__tty_console_width = sb_info.dwSize.X;

      uv__tty_console_height = sb_info.srWindow.Bottom - sb_info.srWindow.Top + 1;

    }

  }

}

int uv_tty_init(uv_loop_t* loop, uv_tty_t* tty, uv_file fd, int unused) {

  BOOL readable;

  DWORD NumberOfEvents;

  HANDLE handle;

  CONSOLE_SCREEN_BUFFER_INFO screen_buffer_info;

  CONSOLE_CURSOR_INFO cursor_info;

  (void)unused;

  uv__once_init();

  handle = (HANDLE) uv__get_osfhandle(fd);

  if (handle == INVALID_HANDLE_VALUE)

    return UV_EBADF;

  if (fd <= 2) {

    /* In order to avoid closing a stdio file descriptor 0-2, duplicate the

     * underlying OS handle and forget about the original fd.

     * We could also opt to use the original OS handle and just never close it,

     * but then there would be no reliable way to cancel pending read operations

     * upon close.

     */

    if (!DuplicateHandle(INVALID_HANDLE_VALUE,

                         handle,

                         INVALID_HANDLE_VALUE,

                         &handle,

                         0,

                         FALSE,

                         DUPLICATE_SAME_ACCESS))

      return uv_translate_sys_error(GetLastError());

    fd = -1;

  }

  readable = GetNumberOfConsoleInputEvents(handle, &NumberOfEvents);

  if (!readable) {

    /* Obtain the screen buffer info with the output handle. */

    if (!GetConsoleScreenBufferInfo(handle, &screen_buffer_info)) {

      return uv_translate_sys_error(GetLastError());

    }

    /* Obtain the cursor info with the output handle. */

    if (!GetConsoleCursorInfo(handle, &cursor_info)) {

      return uv_translate_sys_error(GetLastError());

    }

    /* Obtain the tty_output_lock because the virtual window state is shared

     * between all uv_tty_t handles. */

    uv_sem_wait(&uv_tty_output_lock);

    if (uv__need_check_vterm_state)

      uv__determine_vterm_state(handle);

    /* Remember the original console text attributes and cursor info. */

    uv_tty_capture_initial_style(&screen_buffer_info, &cursor_info);

    uv_tty_update_virtual_window(&screen_buffer_info);

    uv_sem_post(&uv_tty_output_lock);

  }

  uv_stream_init(loop, (uv_stream_t*) tty, UV_TTY);

  uv_connection_init((uv_stream_t*) tty);

  tty->handle = handle;

  tty->u.fd = fd;

  tty->reqs_pending = 0;

  tty->flags |= UV_HANDLE_BOUND;

  if (readable) {

    /* Initialize TTY input specific fields. */

    tty->flags |= UV_HANDLE_TTY_READABLE | UV_HANDLE_READABLE;

    /* TODO: remove me in v2.x. */

    tty->tty.rd.unused_ = NULL;

    tty->tty.rd.read_line_buffer = uv_null_buf_;

    tty->tty.rd.read_raw_wait = NULL;

    /* Init keycode-to-vt100 mapper state. */

    tty->tty.rd.last_key_len = 0;

    tty->tty.rd.last_key_offset = 0;

    tty->tty.rd.last_utf16_high_surrogate = 0;

    memset(&tty->tty.rd.last_input_record, 0, sizeof tty->tty.rd.last_input_record);

  } else {

    /* TTY output specific fields. */

    tty->flags |= UV_HANDLE_WRITABLE;

    /* Init utf8-to-utf16 conversion state. */

    tty->tty.wr.utf8_bytes_left = 0;

    tty->tty.wr.utf8_codepoint = 0;

    /* Initialize eol conversion state */

    tty->tty.wr.previous_eol = 0;

    /* Init ANSI parser state. */

    tty->tty.wr.ansi_parser_state = ANSI_NORMAL;

  }

  return 0;

}

/* Set the default console text attributes based on how the console was

 * configured when libuv started.

 */

static void uv_tty_capture_initial_style(

    CONSOLE_SCREEN_BUFFER_INFO* screen_buffer_info,

    CONSOLE_CURSOR_INFO* cursor_info) {

  static int style_captured = 0;

  /* Only do this once.

     Assumption: Caller has acquired uv_tty_output_lock. */

  if (style_captured)

    return;

  /* Save raw win32 attributes. */

  uv_tty_default_text_attributes = screen_buffer_info->wAttributes;

  /* Convert black text on black background to use white text. */

  if (uv_tty_default_text_attributes == 0)

    uv_tty_default_text_attributes = 7;

  /* Convert Win32 attributes to ANSI colors. */

  uv_tty_default_fg_color = 0;

  uv_tty_default_bg_color = 0;

  uv_tty_default_fg_bright = 0;

  uv_tty_default_bg_bright = 0;

  uv_tty_default_inverse = 0;

  if (uv_tty_default_text_attributes & FOREGROUND_RED)

    uv_tty_default_fg_color |= 1;

  if (uv_tty_default_text_attributes & FOREGROUND_GREEN)

    uv_tty_default_fg_color |= 2;

  if (uv_tty_default_text_attributes & FOREGROUND_BLUE)

    uv_tty_default_fg_color |= 4;

  if (uv_tty_default_text_attributes & BACKGROUND_RED)

    uv_tty_default_bg_color |= 1;

  if (uv_tty_default_text_attributes & BACKGROUND_GREEN)

    uv_tty_default_bg_color |= 2;

  if (uv_tty_default_text_attributes & BACKGROUND_BLUE)

    uv_tty_default_bg_color |= 4;

  if (uv_tty_default_text_attributes & FOREGROUND_INTENSITY)

    uv_tty_default_fg_bright = 1;

  if (uv_tty_default_text_attributes & BACKGROUND_INTENSITY)

    uv_tty_default_bg_bright = 1;

  if (uv_tty_default_text_attributes & COMMON_LVB_REVERSE_VIDEO)

    uv_tty_default_inverse = 1;

  /* Save the cursor size and the cursor state. */

  uv_tty_default_cursor_info = *cursor_info;

  style_captured = 1;

}

int uv_tty_set_mode(uv_tty_t* tty, uv_tty_mode_t mode) {

  DWORD flags;

  unsigned char was_reading;

  uv_alloc_cb alloc_cb;

  uv_read_cb read_cb;

  int err;

  if (!(tty->flags & UV_HANDLE_TTY_READABLE)) {

    return UV_EINVAL;

  }

  if (!!mode == !!(tty->flags & UV_HANDLE_TTY_RAW)) {

    return 0;

  }

  switch (mode) {

    case UV_TTY_MODE_NORMAL:

      flags = ENABLE_ECHO_INPUT | ENABLE_LINE_INPUT | ENABLE_PROCESSED_INPUT;

      break;

    case UV_TTY_MODE_RAW:

      flags = ENABLE_WINDOW_INPUT;

      break;

    case UV_TTY_MODE_IO:

      return UV_ENOTSUP;

    default:

      return UV_EINVAL;

  }

  /* If currently reading, stop, and restart reading. */

  if (tty->flags & UV_HANDLE_READING) {

    was_reading = 1;

    alloc_cb = tty->alloc_cb;

    read_cb = tty->read_cb;

    err = uv_tty_read_stop(tty);

    if (err) {

      return uv_translate_sys_error(err);

    }

  } else {

    was_reading = 0;

    alloc_cb = NULL;

    read_cb = NULL;

  }

  uv_sem_wait(&uv_tty_output_lock);

  if (!SetConsoleMode(tty->handle, flags)) {

    err = uv_translate_sys_error(GetLastError());

    uv_sem_post(&uv_tty_output_lock);

    return err;

  }

  uv_sem_post(&uv_tty_output_lock);

  /* Update flag. */

  tty->flags &= ~UV_HANDLE_TTY_RAW;

  tty->flags |= mode ? UV_HANDLE_TTY_RAW : 0;

  /* If we just stopped reading, restart. */

  if (was_reading) {

    err = uv_tty_read_start(tty, alloc_cb, read_cb);

    if (err) {

      return uv_translate_sys_error(err);

    }

  }

  return 0;

}

int uv_tty_get_winsize(uv_tty_t* tty, int* width, int* height) {

  CONSOLE_SCREEN_BUFFER_INFO info;

  if (!GetConsoleScreenBufferInfo(tty->handle, &info)) {

    return uv_translate_sys_error(GetLastError());

  }

  uv_sem_wait(&uv_tty_output_lock);

  uv_tty_update_virtual_window(&info;;

  uv_sem_post(&uv_tty_output_lock);

  *width = uv_tty_virtual_width;

  *height = uv_tty_virtual_height;

  return 0;

}

static void CALLBACK uv_tty_post_raw_read(void* data, BOOLEAN didTimeout) {

  uv_loop_t* loop;

  uv_tty_t* handle;

  uv_req_t* req;

  assert(data);

  assert(!didTimeout);

  req = (uv_req_t*) data;

  handle = (uv_tty_t*) req->data;

  loop = handle->loop;

  UnregisterWait(handle->tty.rd.read_raw_wait);

  handle->tty.rd.read_raw_wait = NULL;

  SET_REQ_SUCCESS(req);

  POST_COMPLETION_FOR_REQ(loop, req);

}

static void uv_tty_queue_read_raw(uv_loop_t* loop, uv_tty_t* handle) {

  uv_read_t* req;

  BOOL r;

  assert(handle->flags & UV_HANDLE_READING);

  assert(!(handle->flags & UV_HANDLE_READ_PENDING));

  assert(handle->handle && handle->handle != INVALID_HANDLE_VALUE);

  handle->tty.rd.read_line_buffer = uv_null_buf_;

  req = &handle->read_req;

  memset(&req->u.io.overlapped, 0, sizeof(req->u.io.overlapped));

  r = RegisterWaitForSingleObject(&handle->tty.rd.read_raw_wait,

                                  handle->handle,

                                  uv_tty_post_raw_read,

                                  (void*) req,

                                  INFINITE,

                                  WT_EXECUTEINWAITTHREAD | WT_EXECUTEONLYONCE);

  if (!r) {

    handle->tty.rd.read_raw_wait = NULL;

    SET_REQ_ERROR(req, GetLastError());

    uv_insert_pending_req(loop, (uv_req_t*)req);

  }

  handle->flags |= UV_HANDLE_READ_PENDING;

  handle->reqs_pending++;

}

static DWORD CALLBACK uv_tty_line_read_thread(void* data) {

  uv_loop_t* loop;

  uv_tty_t* handle;

  uv_req_t* req;

  DWORD bytes, read_bytes;

  WCHAR utf16[MAX_INPUT_BUFFER_LENGTH / 3];

  DWORD chars, read_chars;

  LONG status;

  COORD pos;

  BOOL read_console_success;

  assert(data);

  req = (uv_req_t*) data;

  handle = (uv_tty_t*) req->data;

  loop = handle->loop;

  assert(handle->tty.rd.read_line_buffer.base != NULL);

  assert(handle->tty.rd.read_line_buffer.len > 0);

  /* ReadConsole can't handle big buffers. */

  if (handle->tty.rd.read_line_buffer.len < MAX_INPUT_BUFFER_LENGTH) {

    bytes = handle->tty.rd.read_line_buffer.len;

  } else {

    bytes = MAX_INPUT_BUFFER_LENGTH;

  }

  /* At last, unicode! One utf-16 codeunit never takes more than 3 utf-8

   * codeunits to encode. */

  chars = bytes / 3;

  status = InterlockedExchange(&uv__read_console_status, IN_PROGRESS);

  if (status == TRAP_REQUESTED) {

    SET_REQ_SUCCESS(req);

    InterlockedExchange(&uv__read_console_status, COMPLETED);

    req->u.io.overlapped.InternalHigh = 0;

    POST_COMPLETION_FOR_REQ(loop, req);

    return 0;

  }

  read_console_success = ReadConsoleW(handle->handle,

                                      (void*) utf16,

                                      chars,

                                      &read_chars,

                                      NULL);

  if (read_console_success) {

    read_bytes = WideCharToMultiByte(CP_UTF8,

                                     0,

                                     utf16,

                                     read_chars,

                                     handle->tty.rd.read_line_buffer.base,

                                     bytes,

                                     NULL,

                                     NULL);

    SET_REQ_SUCCESS(req);

    req->u.io.overlapped.InternalHigh = read_bytes;

  } else {

    SET_REQ_ERROR(req, GetLastError());

  }

  status = InterlockedExchange(&uv__read_console_status, COMPLETED);

  if (status ==  TRAP_REQUESTED) {

    /* If we canceled the read by sending a VK_RETURN event, restore the

       screen state to undo the visual effect of the VK_RETURN */

    if (read_console_success && InterlockedOr(&uv__restore_screen_state, 0)) {

      HANDLE active_screen_buffer;

      active_screen_buffer = CreateFileA("conout$",

                                         GENERIC_READ | GENERIC_WRITE,

                                         FILE_SHARE_READ | FILE_SHARE_WRITE,

                                         NULL,

                                         OPEN_EXISTING,

                                         FILE_ATTRIBUTE_NORMAL,

                                         NULL);

      if (active_screen_buffer != INVALID_HANDLE_VALUE) {

        pos = uv__saved_screen_state.dwCursorPosition;

        /* If the cursor was at the bottom line of the screen buffer, the

           VK_RETURN would have caused the buffer contents to scroll up by one

           line. The right position to reset the cursor to is therefore one line

           higher */

        if (pos.Y == uv__saved_screen_state.dwSize.Y - 1)

          pos.Y--;

        SetConsoleCursorPosition(active_screen_buffer, pos);

        CloseHandle(active_screen_buffer);

      }

    }

    uv_sem_post(&uv_tty_output_lock);

  }

  POST_COMPLETION_FOR_REQ(loop, req);

  return 0;

}

static void uv_tty_queue_read_line(uv_loop_t* loop, uv_tty_t* handle) {

  uv_read_t* req;

  BOOL r;

  assert(handle->flags & UV_HANDLE_READING);

  assert(!(handle->flags & UV_HANDLE_READ_PENDING));

  assert(handle->handle && handle->handle != INVALID_HANDLE_VALUE);

  req = &handle->read_req;

  memset(&req->u.io.overlapped, 0, sizeof(req->u.io.overlapped));

  handle->tty.rd.read_line_buffer = uv_buf_init(NULL, 0);

  handle->alloc_cb((uv_handle_t*) handle, 8192, &handle->tty.rd.read_line_buffer);

  if (handle->tty.rd.read_line_buffer.base == NULL ||

      handle->tty.rd.read_line_buffer.len == 0) {

    handle->read_cb((uv_stream_t*) handle,

                    UV_ENOBUFS,

                    &handle->tty.rd.read_line_buffer);

    return;

  }

  assert(handle->tty.rd.read_line_buffer.base != NULL);

  /* Reset flags  No locking is required since there cannot be a line read

     in progress. We are also relying on the memory barrier provided by

     QueueUserWorkItem*/

  uv__restore_screen_state = FALSE;

  uv__read_console_status = NOT_STARTED;

  r = QueueUserWorkItem(uv_tty_line_read_thread,

                        (void*) req,

                        WT_EXECUTELONGFUNCTION);

  if (!r) {

    SET_REQ_ERROR(req, GetLastError());

    uv_insert_pending_req(loop, (uv_req_t*)req);

  }

  handle->flags |= UV_HANDLE_READ_PENDING;

  handle->reqs_pending++;

}

static void uv_tty_queue_read(uv_loop_t* loop, uv_tty_t* handle) {

  if (handle->flags & UV_HANDLE_TTY_RAW) {

    uv_tty_queue_read_raw(loop, handle);

  } else {

    uv_tty_queue_read_line(loop, handle);

  }

}

static const char* get_vt100_fn_key(DWORD code, char shift, char ctrl,

    size_t* len) {

#define VK_CASE(vk, normal_str, shift_str, ctrl_str, shift_ctrl_str)          \

    case (vk):                                                                \

      if (shift && ctrl) {                                                    \

        *len = sizeof shift_ctrl_str;                                         \

        return "\033" shift_ctrl_str;                                         \

      } else if (shift) {                                                     \

        *len = sizeof shift_str ;                                             \

        return "\033" shift_str;                                              \

      } else if (ctrl) {                                                      \

        *len = sizeof ctrl_str;                                               \

        return "\033" ctrl_str;                                               \

      } else {                                                                \

        *len = sizeof normal_str;                                             \

        return "\033" normal_str;                                             \

      }

  switch (code) {

    /* These mappings are the same as Cygwin's. Unmodified and alt-modified

     * keypad keys comply with linux console, modifiers comply with xterm

     * modifier usage. F1. f12 and shift-f1. f10 comply with linux console, f6.

     * f12 with and without modifiers comply with rxvt. */

    VK_CASE(VK_INSERT,  "[2~",  "[2;2~", "[2;5~", "[2;6~")

    VK_CASE(VK_END,     "[4~",  "[4;2~", "[4;5~", "[4;6~")

    VK_CASE(VK_DOWN,    "[B",   "[1;2B", "[1;5B", "[1;6B")

    VK_CASE(VK_NEXT,    "[6~",  "[6;2~", "[6;5~", "[6;6~")

    VK_CASE(VK_LEFT,    "[D",   "[1;2D", "[1;5D", "[1;6D")

    VK_CASE(VK_CLEAR,   "[G",   "[1;2G", "[1;5G", "[1;6G")

    VK_CASE(VK_RIGHT,   "[C",   "[1;2C", "[1;5C", "[1;6C")

    VK_CASE(VK_UP,      "[A",   "[1;2A", "[1;5A", "[1;6A")

    VK_CASE(VK_HOME,    "[1~",  "[1;2~", "[1;5~", "[1;6~")

    VK_CASE(VK_PRIOR,   "[5~",  "[5;2~", "[5;5~", "[5;6~")

    VK_CASE(VK_DELETE,  "[3~",  "[3;2~", "[3;5~", "[3;6~")

    VK_CASE(VK_NUMPAD0, "[2~",  "[2;2~", "[2;5~", "[2;6~")

    VK_CASE(VK_NUMPAD1, "[4~",  "[4;2~", "[4;5~", "[4;6~")

    VK_CASE(VK_NUMPAD2, "[B",   "[1;2B", "[1;5B", "[1;6B")

    VK_CASE(VK_NUMPAD3, "[6~",  "[6;2~", "[6;5~", "[6;6~")

    VK_CASE(VK_NUMPAD4, "[D",   "[1;2D", "[1;5D", "[1;6D")

    VK_CASE(VK_NUMPAD5, "[G",   "[1;2G", "[1;5G", "[1;6G")

    VK_CASE(VK_NUMPAD6, "[C",   "[1;2C", "[1;5C", "[1;6C")

    VK_CASE(VK_NUMPAD7, "[A",   "[1;2A", "[1;5A", "[1;6A")

    VK_CASE(VK_NUMPAD8, "[1~",  "[1;2~", "[1;5~", "[1;6~")

    VK_CASE(VK_NUMPAD9, "[5~",  "[5;2~", "[5;5~", "[5;6~")

    VK_CASE(VK_DECIMAL, "[3~",  "[3;2~", "[3;5~", "[3;6~")

    VK_CASE(VK_F1,      "[[A",  "[23~",  "[11^",  "[23^" )

    VK_CASE(VK_F2,      "[[B",  "[24~",  "[12^",  "[24^" )

    VK_CASE(VK_F3,      "[[C",  "[25~",  "[13^",  "[25^" )

    VK_CASE(VK_F4,      "[[D",  "[26~",  "[14^",  "[26^" )

    VK_CASE(VK_F5,      "[[E",  "[28~",  "[15^",  "[28^" )

    VK_CASE(VK_F6,      "[17~", "[29~",  "[17^",  "[29^" )

    VK_CASE(VK_F7,      "[18~", "[31~",  "[18^",  "[31^" )

    VK_CASE(VK_F8,      "[19~", "[32~",  "[19^",  "[32^" )

    VK_CASE(VK_F9,      "[20~", "[33~",  "[20^",  "[33^" )

    VK_CASE(VK_F10,     "[21~", "[34~",  "[21^",  "[34^" )

    VK_CASE(VK_F11,     "[23~", "[23$",  "[23^",  "[23@" )

    VK_CASE(VK_F12,     "[24~", "[24$",  "[24^",  "[24@" )

    default:

      *len = 0;

      return NULL;

  }

#undef VK_CASE

}

void uv_process_tty_read_raw_req(uv_loop_t* loop, uv_tty_t* handle,

    uv_req_t* req) {

  /* Shortcut for handle->tty.rd.last_input_record.Event.KeyEvent. */

#define KEV handle->tty.rd.last_input_record.Event.KeyEvent

  DWORD records_left, records_read;

  uv_buf_t buf;

  off_t buf_used;

  assert(handle->type == UV_TTY);

  assert(handle->flags & UV_HANDLE_TTY_READABLE);

  handle->flags &= ~UV_HANDLE_READ_PENDING;

  if (!(handle->flags & UV_HANDLE_READING) ||

      !(handle->flags & UV_HANDLE_TTY_RAW)) {

    goto out;

  }

  if (!REQ_SUCCESS(req)) {

    /* An error occurred while waiting for the event. */

    if ((handle->flags & UV_HANDLE_READING)) {

      handle->flags &= ~UV_HANDLE_READING;

      handle->read_cb((uv_stream_t*)handle,

                      uv_translate_sys_error(GET_REQ_ERROR(req)),

                      &uv_null_buf_);

    }

    goto out;

  }

  /* Fetch the number of events  */

  if (!GetNumberOfConsoleInputEvents(handle->handle, &records_left)) {

    handle->flags &= ~UV_HANDLE_READING;

    DECREASE_ACTIVE_COUNT(loop, handle);

    handle->read_cb((uv_stream_t*)handle,

                    uv_translate_sys_error(GetLastError()),

                    &uv_null_buf_);

    goto out;

  }

  /* Windows sends a lot of events that we're not interested in, so buf will be

   * allocated on demand, when there's actually something to emit. */

  buf = uv_null_buf_;

  buf_used = 0;

  while ((records_left > 0 || handle->tty.rd.last_key_len > 0) &&

         (handle->flags & UV_HANDLE_READING)) {

    if (handle->tty.rd.last_key_len == 0) {

      /* Read the next input record */

      if (!ReadConsoleInputW(handle->handle,

                             &handle->tty.rd.last_input_record,

                             1,

                             &records_read)) {

        handle->flags &= ~UV_HANDLE_READING;

        DECREASE_ACTIVE_COUNT(loop, handle);

        handle->read_cb((uv_stream_t*) handle,

                        uv_translate_sys_error(GetLastError()),

                        &buf;;

        goto out;

      }

      records_left--;

      /* We might be not subscribed to EVENT_CONSOLE_LAYOUT or we might be

       * running under some TTY emulator that does not send those events. */

      if (handle->tty.rd.last_input_record.EventType == WINDOW_BUFFER_SIZE_EVENT) {

        uv__tty_console_signal_resize();

      }

      /* Ignore other events that are not key events. */

      if (handle->tty.rd.last_input_record.EventType != KEY_EVENT) {

        continue;

      }

      /* Ignore keyup events, unless the left alt key was held and a valid

       * unicode character was emitted. */

      if (!KEV.bKeyDown &&

          (KEV.wVirtualKeyCode != VK_MENU ||

           KEV.uChar.UnicodeChar == 0)) {

        continue;

      }

      /* Ignore keypresses to numpad number keys if the left alt is held

       * because the user is composing a character, or windows simulating this.

       */

      if ((KEV.dwControlKeyState & LEFT_ALT_PRESSED) &&

          !(KEV.dwControlKeyState & ENHANCED_KEY) &&

          (KEV.wVirtualKeyCode == VK_INSERT ||

          KEV.wVirtualKeyCode == VK_END ||

          KEV.wVirtualKeyCode == VK_DOWN ||

          KEV.wVirtualKeyCode == VK_NEXT ||

          KEV.wVirtualKeyCode == VK_LEFT ||

          KEV.wVirtualKeyCode == VK_CLEAR ||

          KEV.wVirtualKeyCode == VK_RIGHT ||

          KEV.wVirtualKeyCode == VK_HOME ||

          KEV.wVirtualKeyCode == VK_UP ||

          KEV.wVirtualKeyCode == VK_PRIOR ||

          KEV.wVirtualKeyCode == VK_NUMPAD0 ||

          KEV.wVirtualKeyCode == VK_NUMPAD1 ||

          KEV.wVirtualKeyCode == VK_NUMPAD2 ||

          KEV.wVirtualKeyCode == VK_NUMPAD3 ||

          KEV.wVirtualKeyCode == VK_NUMPAD4 ||

          KEV.wVirtualKeyCode == VK_NUMPAD5 ||

          KEV.wVirtualKeyCode == VK_NUMPAD6 ||

          KEV.wVirtualKeyCode == VK_NUMPAD7 ||

          KEV.wVirtualKeyCode == VK_NUMPAD8 ||

          KEV.wVirtualKeyCode == VK_NUMPAD9)) {

        continue;

      }

      if (KEV.uChar.UnicodeChar != 0) {

        int prefix_len, char_len;

        /* Character key pressed */

        if (KEV.uChar.UnicodeChar >= 0xD800 &&

            KEV.uChar.UnicodeChar < 0xDC00) {

          /* UTF-16 high surrogate */

          handle->tty.rd.last_utf16_high_surrogate = KEV.uChar.UnicodeChar;

          continue;

        }

        /* Prefix with \u033 if alt was held, but alt was not used as part a

         * compose sequence. */

        if ((KEV.dwControlKeyState & (LEFT_ALT_PRESSED | RIGHT_ALT_PRESSED))

            && !(KEV.dwControlKeyState & (LEFT_CTRL_PRESSED |

            RIGHT_CTRL_PRESSED)) && KEV.bKeyDown) {

          handle->tty.rd.last_key[0] = '\033';

          prefix_len = 1;

        } else {

          prefix_len = 0;

        }

        if (KEV.uChar.UnicodeChar >= 0xDC00 &&

            KEV.uChar.UnicodeChar < 0xE000) {

          /* UTF-16 surrogate pair */

          WCHAR utf16_buffer[2];

          utf16_buffer[0] = handle->tty.rd.last_utf16_high_surrogate;

          utf16_buffer[1] = KEV.uChar.UnicodeChar;

          char_len = WideCharToMultiByte(CP_UTF8,

                                         0,

                                         utf16_buffer,

                                         2,

                                         &handle->tty.rd.last_key[prefix_len],

                                         sizeof handle->tty.rd.last_key,

                                         NULL,

                                         NULL);

        } else {

          /* Single UTF-16 character */

          char_len = WideCharToMultiByte(CP_UTF8,

                                         0,

                                         &KEV.uChar.UnicodeChar,

                                         1,

                                         &handle->tty.rd.last_key[prefix_len],

                                         sizeof handle->tty.rd.last_key,

                                         NULL,

                                         NULL);

        }

        /* Whatever happened, the last character wasn't a high surrogate. */

        handle->tty.rd.last_utf16_high_surrogate = 0;

        /* If the utf16 character(s) couldn't be converted something must be

         * wrong. */

        if (!char_len) {

          handle->flags &= ~UV_HANDLE_READING;

          DECREASE_ACTIVE_COUNT(loop, handle);

          handle->read_cb((uv_stream_t*) handle,

                          uv_translate_sys_error(GetLastError()),

                          &buf;;

          goto out;

        }

        handle->tty.rd.last_key_len = (unsigned char) (prefix_len + char_len);

        handle->tty.rd.last_key_offset = 0;

        continue;

      } else {

        /* Function key pressed */

        const char* vt100;

        size_t prefix_len, vt100_len;

        vt100 = get_vt100_fn_key(KEV.wVirtualKeyCode,

                                  !!(KEV.dwControlKeyState & SHIFT_PRESSED),

                                  !!(KEV.dwControlKeyState & (

                                    LEFT_CTRL_PRESSED |

                                    RIGHT_CTRL_PRESSED)),