ncurses-getcommand.c

/* FDUPES Copyright (c) 2018 Adrian Lopez

   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 "config.h"
#include <stdlib.h>
#include <signal.h>
#include "ncurses-getcommand.h"

#define KEY_ESCAPE 27

extern volatile sig_atomic_t got_sigint;

/* get command and arguments from user input */
void get_command_arguments(wchar_t **arguments, wchar_t *input)
{
  size_t l;
  size_t x;

  l = wcslen(input);

  for (x = 0; x < l; ++x)
    if (input[x] == L' ')
      break;

  if (input[x] == L' ')
    *arguments = input + x + 1;
  else
    *arguments = input + x;
}

int get_command_text(wchar_t **commandbuffer, size_t *commandbuffersize, WINDOW *promptwin, struct prompt_info *prompt, int cancel_on_erase, int append)
{
  int docommandinput;
  int keyresult;
  wint_t wch;
  wint_t oldch;
  size_t length;
  size_t newsize;
  wchar_t *realloccommandbuffer;
  size_t c;

  set_prompt_active_state(prompt, 1);
  wrefresh(promptwin);

  if (*commandbuffer == 0)
  {
    *commandbuffersize = 80;
    *commandbuffer = malloc(*commandbuffersize * sizeof(wchar_t));
    if (*commandbuffer == 0)
    {
      set_prompt_active_state(prompt, 0);
      return GET_COMMAND_ERROR_OUT_OF_MEMORY;
    }
  }

  if (!append)
  {
    (*commandbuffer)[0] = L'\0';
  }
  else
  {
    print_prompt(promptwin, prompt, *commandbuffer);

    prompt->cursor = wcswidth(*commandbuffer, wcslen(*commandbuffer));

    wmove(promptwin, 0, wcslen(prompt->text) + prompt->cursor - prompt->offset);

    wrefresh(promptwin);
  }

  docommandinput = 1;
  do
  {
    do
    {
      keyresult = wget_wch(promptwin, &wch);

      if (got_sigint)
      {
        got_sigint = 0;

        (*commandbuffer)[0] = '\0';

        set_prompt_active_state(prompt, 0);

        return GET_COMMAND_CANCELED;
      }
    } while (keyresult == ERR);

    if (keyresult == OK)
    {
      switch (wch)
      {
        case KEY_ESCAPE:
          prompt->offset = 0;
          prompt->cursor = 0;
          docommandinput = 0;

          (*commandbuffer)[0] = '\0';

          set_prompt_active_state(prompt, 0);

          return GET_COMMAND_CANCELED;

        case '\n':
          prompt->offset = 0;
          prompt->cursor = 0;
          docommandinput = 0;
          continue;

        case '\t':
          continue;

        default:
          if (!iswprint(wch))
            continue;

          length = wcslen(*commandbuffer);

          if (length + 1 >= *commandbuffersize)
          {
            newsize = *commandbuffersize * 2;

            realloccommandbuffer = (wchar_t*)realloc(*commandbuffer, newsize * sizeof(wchar_t));
            if (realloccommandbuffer == 0)
            {
              set_prompt_active_state(prompt, 0);
              return GET_COMMAND_ERROR_OUT_OF_MEMORY;
            }

            *commandbuffer = realloccommandbuffer;
            *commandbuffersize = newsize;
          }

          for (c = length + 1; c >= prompt->cursor + 1; --c)
            (*commandbuffer)[c] = (*commandbuffer)[c-1];

          (*commandbuffer)[prompt->cursor] = wch;

          set_prompt_active_state(prompt, 1);

          update_prompt(promptwin, prompt, *commandbuffer, wcwidth(wch));

          break;
      }
    }
    else if (keyresult == KEY_CODE_YES)
    {
      switch (wch)
      {
        case KEY_BACKSPACE:
          length = wcslen(*commandbuffer);

          if (length == 0)
          {
            set_prompt_active_state(prompt, 0);

            if (cancel_on_erase)
              return GET_COMMAND_CANCELED;
          }

          oldch = (*commandbuffer)[prompt->cursor];

          if (prompt->cursor > 0)
            for (c = prompt->cursor; c <= length; ++c)
              (*commandbuffer)[c-1] = (*commandbuffer)[c];

          update_prompt(promptwin, prompt, *commandbuffer, oldch != 0 ? -wcwidth(oldch) : -1);

          break;

        case KEY_DC:
          length = wcslen(*commandbuffer);

          if (prompt->cursor < length)
            for (c = prompt->cursor; c <= length; ++c)
              (*commandbuffer)[c] = (*commandbuffer)[c+1];

          break;

        case KEY_LEFT:
          length = wcslen(*commandbuffer);

          oldch = (*commandbuffer)[prompt->cursor];

          update_prompt(promptwin, prompt, *commandbuffer, oldch != 0 ? -wcwidth(oldch) : -1);

          break;

        case KEY_RIGHT:
          length = wcslen(*commandbuffer);

          oldch = (*commandbuffer)[prompt->cursor];

          if (prompt->cursor + wcwidth((*commandbuffer)[prompt->cursor]) <= length)
            update_prompt(promptwin, prompt, *commandbuffer, wcwidth(oldch));

          break;

        case KEY_NPAGE:
          return GET_COMMAND_KEY_NPAGE;

        case KEY_PPAGE:
          return GET_COMMAND_KEY_PPAGE;

        case KEY_SF:
          return GET_COMMAND_KEY_SF;

        case KEY_SR:
          return GET_COMMAND_KEY_SR;

        case KEY_RESIZE:
          return GET_COMMAND_RESIZE_REQUESTED;
      }
    }

    print_prompt(promptwin, prompt, *commandbuffer);

    wmove(promptwin, 0, wcslen(prompt->text) + prompt->cursor - prompt->offset);

    wrefresh(promptwin);
  } while (docommandinput);

  set_prompt_active_state(prompt, 0);

  return GET_COMMAND_OK;
}