#include "door.h"
#include <algorithm>
#include <chrono>
#include <ctype.h>
#include <string.h>
#include <string>
#include <thread>

#include <libgen.h> // basename

// time/date output std::put_time()
// https://en.cppreference.com/w/cpp/io/manip/put_time
#include <ctime>
#include <iomanip>

// alarm signal
#include <signal.h>
#include <unistd.h>

#include <iconv.h>

#include <algorithm>
#include <iostream>

/*

My strategy here has failed.

If I set enigma to cp437, then it handles everything but the cp437
symbols (diamonds/hearts/spades/clubs) correctly on the unicode side.
[And my door thinks it's all cp437 always]

If I set enigma to utf8, then it works right on the ssh terminal side.
But cp437 turns to puke because it's trying to convert cp437 from
utf8 to cp437.  The symbols get '?'.

I can't detect unicode (when set to utf8), but I can detect cp437
(by sending the diamonds/hearts characters).

But I can't get through the enigma translation system.  If only iconv worked
correctly with hearts/clubs symbols!  Then I wouldn't need this broken
work-around code.
 */

namespace door {

void to_lower(std::string &text) {
  transform(text.begin(), text.end(), text.begin(), ::tolower);
}

bool replace(std::string &str, const std::string &from, const std::string &to) {
  size_t start_pos = str.find(from);
  if (start_pos == std::string::npos)
    return false;
  str.replace(start_pos, from.length(), to);
  return true;
}

bool replace(std::string &str, const char *from, const char *to) {
  size_t start_pos = str.find(from);
  if (start_pos == std::string::npos)
    return false;
  str.replace(start_pos, strlen(from), to);
  return true;
}

static bool hangup = false;

void sig_handler(int signal) {
  hangup = true;
  /*
  ofstream sigf;
  sigf.open("signal.log", std::ofstream::out | std::ofstream::app);

  sigf << "SNAP! GOT: " << signal << std::endl;
  sigf.close();
  */
  // 13 SIGPIPE -- ok, what do I do with this, eh?
}

class IConv {
  iconv_t ic;

public:
  IConv(const char *to, const char *from);
  ~IConv();

  int convert(char *input, char *output, size_t outbufsize);
};

IConv::IConv(const char *to, const char *from) : ic(iconv_open(to, from)) {}
IConv::~IConv() { iconv_close(ic); }

int IConv::convert(char *input, char *output, size_t outbufsize) {
  size_t inbufsize = strlen(input);
  // size_t orig_size = outbufsize;
  // memset(output, 0, outbufsize);
  // https://www.gnu.org/savannah-checkouts/gnu/libiconv/documentation/libiconv-1.15/iconv.3.html
  int r = iconv(ic, &input, &inbufsize, &output, &outbufsize);
  *output = 0;
  return r;
}

static IConv converter("UTF-8", "CP437");

void cp437toUnicode(std::string input, std::string &out) {
  char buffer[10240];
  char output[16384];

  strcpy(buffer, input.c_str());
  converter.convert(buffer, output, sizeof(output));
  out.assign(output);
}

void cp437toUnicode(const char *input, std::string &out) {
  char buffer[10240];
  char output[16384];

  strcpy(buffer, input);
  converter.convert(buffer, output, sizeof(output));
  out.assign(output);
}

bool unicode = false;
bool full_cp437 = false;
bool debug_capture = false;

/**
 * Construct a new Door object using the commandline parameters
 * given to the main function.
 *
 * @example door_example.cpp
 */
Door::Door(std::string dname, int argc, char *argv[])
    : std::ostream(this), doorname{dname},
      has_dropfile{false}, debugging{false}, seconds_elapsed{0},
      previous(COLOR::WHITE), track{true}, cx{1}, cy{1},
      inactivity{120}, node{1} {

  // Setup commandline options
  opt.addUsage("Door++ library by BUGZ (C) 2021");
  opt.addUsage("");
  opt.addUsage(" -h  --help                 Displays this help");
  opt.addUsage(" -l  --local                Local Mode");
  opt.addUsage(" -d  --dropfile [FILENAME]  Load Dropfile");
  opt.addUsage(" -n  --node N               Set node number");
  // opt.addUsage(" -c  --cp437                Force CP437");
  // opt.addUsage(" -b  --bbsname NAME         Set BBS Name");
  opt.addUsage(" -u  --username NAME        Set Username");
  opt.addUsage(" -t  --timeleft N           Set time left");
  opt.addUsage("     --maxtime N            Set max time");
  opt.addUsage("");
  opt.setFlag("help", 'h');
  opt.setFlag("local", 'l');
  opt.setFlag("cp437", 'c');
  opt.setFlag("unicode");
  opt.setFlag("debuggering");
  opt.setOption("dropfile", 'd');
  // opt.setOption("bbsname", 'b');
  opt.setOption("username", 'u');
  opt.setOption("timeleft", 't');
  opt.setOption("maxtime");

  opt.processCommandArgs(argc, argv);

  if (!opt.hasOptions()) {
    opt.printUsage();
    exit(1);
  }

  if (opt.getFlag("help") || opt.getFlag('h')) {
    opt.printUsage();
    exit(1);
  }

  if (opt.getValue("username") != nullptr) {
    username = opt.getValue("username");
  }

  if (opt.getFlag("debuggering")) {
    debugging = true;
  }

  if (opt.getValue("node") != nullptr) {
    node = atoi(opt.getValue("node"));
  }

  if (opt.getValue("timeleft") != nullptr) {
    time_left = atoi(opt.getValue("timeleft"));
  } else {
    // sensible default
    time_left = 25;
  }

  time_used = 0;

  /*
  if (opt.getValue("bbsname") != nullptr) {
    bbsname = opt.getValue("bbsname");
  }
  */

  std::string logFileName = dname + ".log";
  logf.open(logFileName.c_str(), std::ofstream::out | std::ofstream::app);

  parse_dropfile(opt.getValue("dropfile"));

  /*
  If the dropfile has time_left, we'll use it.

  Adjust time_left by maxtime value (if given).
   */

  if (opt.getValue("maxtime") != nullptr) {
    int maxtime = atoi(opt.getValue("maxtime"));
    if (time_left > maxtime) {
      logf << "Adjusting time from " << time_left << " to " << maxtime
           << std::endl;
      time_left = maxtime;
    }
  }

  if (opt.getFlag("local")) {
    if (username.empty()) {
      std::cout << "Local mode requires username to be set." << std::endl;
      opt.printUsage();
      exit(1);
    }
  } else {
    // we must have a dropfile, or else!
    if (!has_dropfile) {
      std::cout << "I require a dropfile.  And a shrubbery." << std::endl;
      opt.printUsage();
      exit(1);
    }
  }

  // Set program name

  log() << "Door init" << std::endl;
  init();

  // door.sys doesn't give BBS name. system_name
  if (!debugging) {
    detect_unicode_and_screen();
    logf << "Screen " << width << " X " << height << " unicode " << unicode
         << " full_cp437 " << full_cp437 << std::endl;
  }

  if (opt.getFlag("cp437")) {
    unicode = false;
  }
  if (opt.getFlag("unicode")) {
    unicode = true;
  }
}

Door::~Door() {
  // restore default mode
  // tcsetattr(STDIN_FILENO, TCSANOW, &tio_default);
  log() << "dtor" << std::endl;
  tcsetattr(STDIN_FILENO, TCOFLUSH, &tio_default);
  signal(SIGHUP, SIG_DFL);
  signal(SIGPIPE, SIG_DFL);

  // time thread
  stop_thread.set_value();
  time_thread.join();
  log() << "done" << std::endl;
  logf.close();
}

// https://www.tutorialspoint.com/how-do-i-terminate-a-thread-in-cplusplus11

void Door::time_thread_run(std::future<void> future) {
  while (future.wait_for(std::chrono::milliseconds(1)) ==
         std::future_status::timeout) {
    // std::cout << "Executing the thread....." << std::endl;
    std::this_thread::sleep_for(std::chrono::seconds(1));
    ++seconds_elapsed;
    // log("TICK");
    // logf << "TICK " << seconds_elapsed << std::endl;
    if (seconds_elapsed % 60 == 0) {
      if (time_left > 0)
        --time_left;
      ++time_used;
    }
  }
}

void Door::init(void) {
  // https://viewsourcecode.org/snaptoken/kilo/02.enteringRawMode.html
  // https://viewsourcecode.org/snaptoken/kilo/03.rawInputAndOutput.html
  // ok!  I didn't know about VTIME !  That's something different!

  // enable terminal RAW mode
  struct termios tio_raw;
  tcgetattr(STDIN_FILENO, &tio_default);
  tio_raw = tio_default;
  cfmakeraw(&tio_raw);
  // local terminal magic
  tio_raw.c_cc[VMIN] = 0;
  tio_raw.c_cc[VTIME] = 1;

  bpos = 0;
  tcsetattr(STDIN_FILENO, TCSANOW, &tio_raw);

  startup = std::time(nullptr);
  signal(SIGHUP, sig_handler);
  signal(SIGPIPE, sig_handler);

  // time thread
  std::future<void> stop_future = stop_thread.get_future();
  time_thread =
      std::thread(&Door::time_thread_run, this, std::move(stop_future));
}

void Door::detect_unicode_and_screen(void) {
  unicode = false;
  full_cp437 = false;
  width = 0;
  height = 0;

  if (!isatty(STDIN_FILENO)) {
    // https://stackoverflow.com/questions/273261/force-telnet-client-into-character-mode
    *this << "\377\375\042\377\373\001"; // fix telnet client
  }

  // maybe I need to be trying to detect cp437 instead of trying to detect
  // unicde!

  *this << "\x1b[0;30;40m\x1b[2J\x1b[H"; // black on black, clrscr, go home
  // *this << "\u2615"
  *this << "\x03\x04" // hearts and diamonds
        << "\x1b[6n"; // cursor pos
  *this << door::nl << "\u2615"
        << "\x1b[6n";                   // hot beverage + cursor pos
  *this << "\x1b[999C\x1b[999B\x1b[6n"; // goto end of screen + cursor pos
  *this << reset << "\x1b[2J\x1b[H";    // reset, cls, go home

  this->flush();
  usleep(1000 * 1000);

  if (haskey()) {
    char buffer[101];
    int len;
    len = read(STDIN_FILENO, &buffer, sizeof(buffer) - 1);
    // logf << "read " << len << std::endl;
    if (len > 0) {
      buffer[len] = 0;
      int x;
      /*
      for (x = 0; x < len; x++) {
        if (buffer[x] < 0x20)
          logf << std::hex << (int)buffer[x] << " ";
        else
          logf << buffer[x] << " ";
      }
      */
      for (x = 0; x < len; x++) {
        if (buffer[x] == 0)
          buffer[x] = ' ';
      }

      /*
      logf << std::endl;
      logf << "BUFFER [" << (char *)buffer << "]" << std::endl;
      */
      if (1) {
        std::string cleanbuffer = buffer;
        std::string esc = "\x1b";
        std::string esc_text = "^[";

        while (replace(cleanbuffer, esc, esc_text)) {
        };

        logf << "BUFFER [" << cleanbuffer << "]" << std::endl;
      }
      // this did not work -- because of the null characters in the buffer.

      // 1;3R required on David's machine.  I'm not sure why.
      // 1;3R also happens under VSCodium.
      // 1;4R is what I get from syncterm.

      if (( (strstr(buffer, "1;1R") != nullptr) or 
		      (strstr(buffer, "1;3R") != nullptr) )
	      and
          ((strstr(buffer, "2;2R") != nullptr) or
           (strstr(buffer, "2;3R") != nullptr))) {

        // if ((strstr(buffer, "1;2R") != nullptr) or
        //    (strstr(buffer, "1;3R") != nullptr)) {
        unicode = true;
        log() << "unicode enabled \u2615" << std::endl; // "U0001f926");
      } else {
        if (strstr(buffer, "1;3R") != nullptr) {
          full_cp437 = true;
        }
      }
      // Get the terminal screen size
      // \x1b[1;2R\x1b[41;173R
      // log(buffer);

      char *cp;
      /*
      cp = strchr(buffer, '\x1b');
      if (cp != nullptr) {
        cp = strchr(cp + 1, '\x1b');
      } else {
        log() << "Failed terminal size detection.  See buffer:" << std::endl;
        log() << buffer << std::endl;
        return;
      }
      */
      cp = strrchr(buffer, '\x1b');

      if (cp != nullptr) {
        cp++;
        if (*cp == '[') {
          cp++;
          height = atoi(cp);
          cp = strchr(cp, ';');
          if (cp != nullptr) {
            cp++;
            width = atoi(cp);
            // magiterm reports 25;923R !
            if (width > 900) {
              width = 0;
              height = 0;
            }
          } else {
            height = 0;
          }
        }
      }
    }
  } else {
    logf << "FAIL-WHALE, no response to terminal getposition." << std::endl;
  }
}

void Door::parse_dropfile(const char *filepath) {
  if (filepath == nullptr)
    return;

  // Ok, parse file here...
  std::ifstream file(filepath);
  std::string line;
  while (std::getline(file, line)) {
    // These are "DOS" files.  Remove trailing \r.
    if (!line.empty() && line[line.size() - 1] == '\r')
      line.erase(line.size() - 1);
    dropfilelines.push_back(line);
  }
  file.close();

  std::string filename;
  {
    // converting const char * to char * for basename.
    char *temp = strdup(filepath);
    filename = basename(temp);
    free(temp);
  }

  to_lower(filename);

  // for now, just door.sys.

  if (filename == "door.sys") {
    // Ok, parse away!
    node = atoi(dropfilelines[3].c_str());
    username = dropfilelines[9];
    location = dropfilelines[10];
    time_left = atoi(dropfilelines[18].c_str());
    sysop = dropfilelines[34];
    handle = dropfilelines[35];
  } else {
    if (filename == "door32.sys") {
      // https://raw.githubusercontent.com/NuSkooler/ansi-bbs/master/docs/dropfile_formats/door32_sys.txt
      // dropfilelines[0] = Comm type (0=local, 1=serial, 2=telnet)
      // dropfilelines[1] = Comm or Socket handle
      // dropfilelines[2] = BaudRate
      // dropfilelines[3] = BBS Software Version
      username = dropfilelines[4];
      handle = dropfilelines[5];
      time_left = atoi(dropfilelines[6].c_str());
      // dropfilelines[7] = Emulation (0=Ascii, 1=ANSI, .. or above = ANSI)
      node = atoi(dropfilelines[8].c_str());
    } else {
      std::string msg = "Unknown dropfile: ";
      msg += filename;
      log() << msg << std::endl;
      *this << msg << std::endl;
      exit(2);
    }
  }
  log() << "node:" << node << " username: " << username << " handle: " << handle
        << " time: " << time_left << std::endl;
  has_dropfile = true;
}

ofstream &Door::log(void) {
  // todo:  have logging

  std::time_t t = std::time(nullptr);
  std::tm tm = *std::localtime(&t);
  logf << std::put_time(&tm, "%c ");
  return logf; // << output << std::endl;
}

bool Door::haskey(void) {
  fd_set socket_set;
  struct timeval tv;
  int select_ret = -1;

  if (hangup)
    return -2;

  if (time_left < 2)
    return -3;

  while (select_ret == -1) {
    FD_ZERO(&socket_set);
    FD_SET(STDIN_FILENO, &socket_set);

    tv.tv_sec = 0;
    tv.tv_usec = 1;

    select_ret = select(STDIN_FILENO + 1, &socket_set, NULL, NULL, &tv);
    if (select_ret == -1) {
      if (errno == EINTR)
        continue;
      log() << "hangup detected" << std::endl;
      hangup = true;
      return (-2);
    }
    if (select_ret == 0)
      return false;
  }
  return true;
}

/*
  low-lever read a key from terminal or stdin.
  Returns key, or
  -1 (no key available)
  -2 (read error)
 */
signed int Door::getch(void) {
  fd_set socket_set;
  struct timeval tv;
  int select_ret = -1;
  int recv_ret;
  char key;

  if (door::hangup)
    return -2;

  if (time_left < 2)
    return -3;

  while (select_ret == -1) {
    FD_ZERO(&socket_set);
    FD_SET(STDIN_FILENO, &socket_set);

    // This delay isn't long enough for QModem in a DOSBOX.
    // doorway mode arrow keys aren't always caught.
    tv.tv_sec = 0;
    tv.tv_usec = 100;
    // tv.tv_usec = 500;

    select_ret = select(STDIN_FILENO + 1, &socket_set, NULL, NULL, &tv);
    // select(STDIN_FILENO + 1, &socket_set, NULL, NULL, bWait ? NULL : &tv);
    if (select_ret == -1) {
      if (errno == EINTR)
        continue;
      log() << "hangup detected" << std::endl;
      door::hangup = true;
      return (-2);
    }
    if (select_ret == 0)
      return (-1);
  }

  recv_ret = read(STDIN_FILENO, &key, 1);
  if (recv_ret != 1) {
    // possibly log this.
    log() << "hangup" << std::endl;
    hangup = true;
    return -2;
  }
  // debug weird keys/layouts.
  // log() << "read " << std::hex << (int)key << std::endl;
  return key;
}

void Door::unget(char c) {
  if (bpos < sizeof(buffer) - 1) {
    buffer[bpos] = c;
    bpos++;
  }
}

char Door::get(void) {
  if (bpos == 0)
    return 0;
  bpos--;
  return buffer[bpos];
}

signed int Door::getkey(void) {
  signed int c, c2;

  if (bpos != 0) {
    c = get();
  } else {
    c = getch();
  }

  if (c < 0)
    return c;

  /*
  We get 0x0d 0x00 for [Enter] (Syncterm)
  From David's syncterm, I'm getting 0x0d 0x0a.
  This strips out the null.
  */
  if (c == 0x0d) {
    c2 = getch();
    if ((c2 != 0) and (c2 >= 0) and (c2 != 0x0a)) {
      log() << "got " << (int)c2 << " so stuffing it into unget buffer."
            << std::endl;
      unget(c2);
    }
    return c;
  }

  if (c == 0) {
    // possibly "doorway mode"
    int tries = 0;

    c2 = getch();
    while (c2 < 0) {
      if (tries > 7) {
        log() << "ok, got " << c2 << " and " << tries << " so returning 0x00!"
              << std::endl;

        return c;
      }
      c2 = getch();
      ++tries;
    }

    if (tries > 0) {
      log() << "tries " << tries << std::endl;
    }

    switch (c2) {
    case 0x50:
      return XKEY_DOWN_ARROW;
    case 0x48:
      return XKEY_UP_ARROW;
    case 0x4b:
      return XKEY_LEFT_ARROW;
    case 0x4d:
      return XKEY_RIGHT_ARROW;
    case 0x47:
      return XKEY_HOME;
    case 0x4f:
      return XKEY_END;
    case 0x49:
      return XKEY_PGUP;
    case 0x51:
      return XKEY_PGDN;
    case 0x3b:
      return XKEY_F1;
    case 0x3c:
      return XKEY_F2;
    case 0x3d:
      return XKEY_F3;
    case 0x3e:
      return XKEY_F4;
    case 0x3f:
      return XKEY_F5;
    case 0x40:
      return XKEY_F6;
    case 0x41:
      return XKEY_F7;
    case 0x42:
      return XKEY_F8;
    case 0x43:
      return XKEY_F9;
    case 0x44:
      return XKEY_F10;
      /*
    case 0x45:
      return XKEY_F11;
    case 0x46:
      return XKEY_F12;
      */
    case 0x52:
      return XKEY_INSERT;
    case 0x53:
      return XKEY_DELETE;
    }
    logf << "\r\nDEBUG:\r\n0x00 + 0x" << std::hex << (int)c2;
    logf << "\r\n";
    logf.flush();
  }

  if (c == 0x1b) {
    // possible extended key
    c2 = getch();
    if (c2 < 0) {
      // nope, just plain ESC key
      return c;
    }

    // consume extended key values int extended buffer
    char extended[16];
    unsigned int pos = 0;
    extended[pos] = (char)c2;
    extended[pos + 1] = 0;
    pos++;
    while ((pos < sizeof(extended) - 1) and ((c2 = getch()) >= 0)) {
      // special case here where I'm sending out cursor location requests
      // and the \x1b[X;YR strings are getting buffered.
      if (c2 == 0x1b) {
        unget(c2);
        break;
      }
      extended[pos] = (char)c2;
      extended[pos + 1] = 0;
      pos++;
    }

    // convert extended buffer to special key
    if (extended[0] == '[') {
      switch (extended[1]) {
      case 'A':
        return XKEY_UP_ARROW;
      case 'B':
        return XKEY_DOWN_ARROW;
      case 'C':
        return XKEY_RIGHT_ARROW;
      case 'D':
        return XKEY_LEFT_ARROW;
      case 'H':
        return XKEY_HOME;
      case 'F':
        return XKEY_END; // terminal
      case 'K':
        return XKEY_END;
      case 'U':
        return XKEY_PGUP;
      case 'V':
        return XKEY_PGDN;
      case '@':
        return XKEY_INSERT;
      }

      if (extended[pos - 1] == '~') {
        // \x1b[digits~
        int number = atoi(extended + 1);
        switch (number) {
        case 2:
          return XKEY_INSERT; // terminal
        case 3:
          return XKEY_DELETE; // terminal
        case 5:
          return XKEY_PGUP; // terminal
        case 6:
          return XKEY_PGDN; // terminal
        case 15:
          return XKEY_F5; // terminal
        case 17:
          return XKEY_F6; // terminal
        case 18:
          return XKEY_F7; // terminal
        case 19:
          return XKEY_F8; // terminal
        case 20:
          return XKEY_F9; // terminal
        case 21:
          return XKEY_F10; // terminal
        case 23:
          return XKEY_F11;
        case 24:
          return XKEY_F12; // terminal
        }
      }
    }

    if (extended[0] == 'O') {
      switch (extended[1]) {
      case 'P':
        return XKEY_F1;
      case 'Q':
        return XKEY_F2;
      case 'R':
        return XKEY_F3;
      case 'S':
        return XKEY_F4;
      case 't':
        return XKEY_F5; // syncterm
      }
    }

    // unknown -- This needs to be logged
    logf << "\r\nDEBUG:\r\nESC + ";
    for (unsigned int x = 0; x < pos; x++) {
      char z = extended[x];
      if (iscntrl(z)) {
        logf << (int)z << " ";
      } else {
        logf << "'" << (char)z << "'"
             << " ";
      };
    }
    logf << "\r\n";
    logf.flush();

    return XKEY_UNKNOWN;
  }
  return c;
}

int Door::get_input(void) {
  signed int c;
  c = getkey();
  if (c < 0)
    return 0;
  return c;

  /*
  tODInputEvent event;
  od_get_input(&event, OD_NO_TIMEOUT, GETIN_NORMAL);
  */
}

/*
The following code will wait for 1.5 second:

#include <sys/select.h>
#include <sys/time.h>
#include <unistd.h>`

int main() {
    struct timeval t;
    t.tv_sec = 1;
    t.tv_usec = 500000;
    select(0, NULL, NULL, NULL, &t);
}

 */
signed int Door::sleep_key(int secs) {
  fd_set socket_set;
  struct timeval tv;
  int select_ret = -1;
  /*
  int recv_ret;
  char key;
  */
  if (hangup)
    return -2;

  if (time_left < 2)
    return -3;

  while (select_ret == -1) {
    FD_ZERO(&socket_set);
    FD_SET(STDIN_FILENO, &socket_set);

    tv.tv_sec = secs;
    tv.tv_usec = 0;

    select_ret = select(STDIN_FILENO + 1, &socket_set, NULL, NULL, &tv);
    // select(STDIN_FILENO + 1, &socket_set, NULL, NULL, bWait ? NULL : &tv);
    if (select_ret == -1) {
      if (errno == EINTR)
        continue;
      hangup = true;
      log() << "hangup detected" << std::endl;
      return (-2);
    }
    if (select_ret == 0)
      return (-1);
  }
  return getkey();
}

std::string Door::input_string(int max) {
  std::string input;

  // draw the input area.
  *this << std::string(max, ' ');
  *this << std::string(max, '\x08');

  int c;

  while (true) {
    c = sleep_key(inactivity);
    if (c < 0) {
      input.clear();
      return input;
    }
    if (c > 0x1000)
      continue;

    if (isprint(c)) {
      if (int(input.length()) < max) {
        *this << char(c);
        input.append(1, c);
      } else {
        // bell
        *this << '\x07';
      }
    } else {
      switch (c) {
      case 0x08:
      case 0x7f:
        if (input.length() > 0) {
          *this << "\x08 \x08";
          // this->flush();
          input.erase(input.length() - 1);
        };
        break;
      case 0x0d:
        return input;
      }
    }
  }
}

/**
 * @brief Get one of these keys
 *
 * returns char, or < 0 if timeout.
 *
 * @param keys
 * @return char or < 0
 */
int Door::get_one_of(const char *keys) {
  int c;
  while (true) {
    c = sleep_key(inactivity);
    if (c < 0)
      return c;

    if (c > 0x1000)
      continue;
    const char *key = strchr(keys, (char)toupper(c));
    if (key != nullptr) {
      return *key;
    }
    *this << '\x07';
  }
  return c;
}

/**
 * Take given buffer and output it.
 *
 * If debug_capture is enabled, we save everything to debug_buffer.
 * This is used by the tests.
 *
 * @param s const char *
 * @param n std::streamsize
 * @return std::streamsize
 */
std::streamsize Door::xsputn(const char *s, std::streamsize n) {
  if (debug_capture) {
    debug_buffer.append(s, n);
  } else {
    static std::string buffer;
    buffer.append(s, n);
    // setp(&(*buffer.begin()), &(*buffer.end()));
    if (!hangup) {
      std::cout << buffer;
      std::cout.flush();
    }
    // Tracking character position could be a problem / local terminal unicode.
    if (track)
      cx += n;
    buffer.clear();
  }
  return n;
}

/**
 * Stores a character into the buffer.
 * This does still use the buffer.
 * @todo Replace this also with a direct call to od_disp_emu.
 *
 * @param c char
 * @return int
 */
int Door::overflow(int c) {
  if (debug_capture) {
    debug_buffer.append(1, (char)c);
  } else {
    if (!hangup) {
      std::cout << (char)c;
      std::cout.flush();
    }
  }
  if (track)
    cx++;
  // setp(&(*buffer.begin()), &(*buffer.end()));
  return c;
}

/**
 * Construct a new Color Output:: Color Output object
 * We default to BLACK/BLACK (not really a valid color),
 * pos=0 and len=0.
 */
ColorOutput::ColorOutput() : c(COLOR::BLACK, COLOR::BLACK) {
  pos = 0;
  len = 0;
}

/**
 * Reset pos and len to 0.
 */
void ColorOutput::reset(void) {
  pos = 0;
  len = 0;
}

/**
 * Construct a new Render:: Render object
 *
 * Render consists of constant text,
 * and vector of ColorOutput
 *
 * @param txt Text
 */
Render::Render(const std::string txt) : text{txt} {}

/**
 * Output the Render.
 *
 * This consists of going through the vector, getting
 * the fragment (from pos and len), and outputting the
 * color and fragment.
 *
 * @param os
 */
void Render::output(std::ostream &os) {
  for (auto out : outputs) {
    std::string fragment = text.substr(out.pos, out.len);
    os << out.c << fragment;
  }
}

/**
 * Create render output.
 *
 * Call this for each section you want to colorize.
 *
 * @param color
 * @param len
 */
void Render::append(ANSIColor color, int len) {
  if (outputs.empty()) {
    ColorOutput co;
    co.c = color;
    co.pos = 0;
    co.len = len;
    outputs.push_back(co);
    return;
  }
  ColorOutput &current = outputs.back();
  if (current.c == color) {
    current.len += len;
    return;
  }
  // Ok, new entry
  // beware the unicode text
  ColorOutput co;
  co.pos = current.pos + current.len;
  co.c = color;
  co.len = len;
  outputs.push_back(co);
}

/**
 * Construct a new Clrscr:: Clrscr object
 *
 * This is used to clear the screen.
 */
Clrscr::Clrscr() {}

/**
 * Clear the screen using ANSI codes.
 *
 * Not all systems home the cursor after clearing the screen.
 * We automatically home the cursor as well.
 *
 * @param os std::ostream&
 * @param clr const Clrscr&
 * @return std::ostream&
 */
std::ostream &operator<<(std::ostream &os, const Clrscr &clr) {
  Door *d = dynamic_cast<Door *>(&os);
  if (d != nullptr) {
    d->track = false;
    *d << "\x1b[2J"
          "\x1b[H";
    d->cx = 1;
    d->cy = 1;
    d->track = true;
  } else {
    os << "\x1b[2J"
          "\x1b[H";
  }
  return os;
}

Clrscr cls;

/**
 * This is used to issue NL+CR
 *
 */
NewLine::NewLine() {}

/**
 * Output Newline + CarriageReturn
 * @param os std::ostream
 * @param nl const NewLine
 * @return std::ostream&
 */
std::ostream &operator<<(std::ostream &os, const NewLine &nl) {
  Door *d = dynamic_cast<Door *>(&os);
  if (d != nullptr) {
    d->track = false;
    *d << "\r\n";
    d->cx = 1;
    d->cy++;
    d->track = true;
  } else {
    os << "\r\n";
  };
  return os;
}

NewLine nl;

/**
 * Construct a new Goto:: Goto object
 *
 * @param xpos
 * @param ypos
 */
Goto::Goto(int xpos, int ypos) {
  x = xpos;
  y = ypos;
}

void Goto::set(int xpos, int ypos) {
  x = xpos;
  y = ypos;
}

/**
 * Output the ANSI codes to position the cursor to the given y,x position.
 *
 * @todo Optimize the ANSI goto string output.
 * @todo Update the Door object so it know where the cursor
 * is positioned.
 *
 * @param os std::ostream
 * @param g const Goto
 * @return std::ostream&
 */
std::ostream &operator<<(std::ostream &os, const Goto &g) {
  Door *d = dynamic_cast<Door *>(&os);
  if (d != nullptr) {
    d->track = false;
    *d << "\x1b[";
    if (g.y > 1)
      *d << std::to_string(g.y);

    if (g.x > 1) {
      os << ";";
      *d << std::to_string(g.x);
    }
    *d << "H";
    d->cx = g.x;
    d->cy = g.y;
    d->track = true;
  } else {
    os << "\x1b[" << std::to_string(g.y) << ";" << std::to_string(g.x) << "H";
  };
  return os;
}

const char SaveCursor[] = "\x1b[s";
const char RestoreCursor[] = "\x1b[u";

// EXAMPLES

/// BlueYellow Render example function
renderFunction rBlueYellow = [](const std::string &txt) -> Render {
  Render r(txt);

  ANSIColor blue(COLOR::BLUE, ATTR::BOLD);
  ANSIColor cyan(COLOR::YELLOW, ATTR::BOLD);

  for (char const &c : txt) {
    if (isupper(c))
      r.append(blue);
    else
      r.append(cyan);
  }
  return r;
};

} // namespace door