#include "shellio.h"
#include "ansi.h"
#include "utf8.h"
#include <cstdio>
#include <fcntl.h>
#include <iostream>
#include <termios.h>
#include <unistd.h>
namespace detz::shell {
namespace {
// getpass.getpass(prompt): prompt on the tty, no echo, newline after
std::optional<std::string> GetPass(const std::string& prompt) {
  int fd = ::open("/dev/tty", O_RDWR | O_NOCTTY);
  bool own = fd >= 0;
  if (fd < 0) fd = 0;
  struct termios old, quiet;
  bool changed = false;
  if (::tcgetattr(fd, &old) == 0) {
    quiet = old;
    quiet.c_lflag &= ~(tcflag_t)ECHO;
    changed = ::tcsetattr(fd, TCSAFLUSH, &quiet) == 0;
  }
  int out = own ? fd : 2;
  (void)!::write(out, prompt.data(), prompt.size());
  std::string line;
  bool got = false, eof = false;
  char c;
  while (true) {
    ssize_t n = ::read(fd, &c, 1);
    if (n <= 0) { eof = true; break; }
    got = true;
    if (c == '\n') break;
    line.push_back(c);
  }
  if (changed) ::tcsetattr(fd, TCSAFLUSH, &old);
  (void)!::write(out, "\n", 1);
  if (own) ::close(fd);
  if (eof && !got) return std::nullopt;  // EOFError
  return line;
}
std::optional<std::string> Input(const std::string& prompt) {
  std::fputs(prompt.c_str(), stdout);
  std::fflush(stdout);
  std::string line;
  if (!std::getline(std::cin, line)) return std::nullopt;  // EOFError
  return line;
}
}  // namespace

std::unique_ptr<StreamSink> ShellIo::Stream(ShellApp& app, const std::string& command, bool live) {
  if (app.HasStreamFactory()) return app.StreamFactory(app.Redact(command));
  if (live && ::isatty(1)) return std::make_unique<LiveStream>();
  return nullptr;
}

AskFn ShellIo::Ask(ShellApp& app, const std::string& command) {
  if (app.Auto() || !app.Persist() || app.Depth() > 0) return nullptr;
  ShellApp* a = &app;
  auto answered = [a](std::optional<std::string> value) {
    if (value) a->MarkUserSteppedIn();
    return value;
  };
  if (app.HasPrompter()) {
    std::string head = Utf8::Head(command, 60);
    return [a, head, answered](const std::string& text, bool) { return answered(a->Prompt("ask", head + " asks:\n" + text, {})); };
  }
  if (!(::isatty(0) && ::isatty(1))) return nullptr;
  return [answered](const std::string& text, bool secret) -> std::optional<std::string> {
    std::string prompt = Paint("\xc2\xbb " + text + " ", Ansi::kYellow);
    return answered(secret ? GetPass(prompt) : Input(prompt));
  };
}
}  // namespace detz::shell