#include <QGuiApplication>
#include <csignal>
#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <poll.h>
#include <sys/prctl.h>
#include <sys/wait.h>
#include <thread>
#include <unistd.h>

#include "qmlhandler.h"
#include <boost/asio.hpp>
#include <iostream>
#include <json/json.h>

using boost::asio::buffer;

using namespace std;

int inpipefd[2];
int outpipefd[2];
char buf[1025];
QUrl sendFileUrl = QUrl("");

bool programActive = true;

QMLHandler::QMLHandler(QObject *parent) : QObject(parent) {}

void QMLHandler::onExit() {
  write(outpipefd[1], "disconnect\n", strlen("disconnect\n"));
}

// This method gets a string and tries to read it as Json
// If it fails to do so, return and do nothing, else handle the content
void QMLHandler::handleJSON(string buffer) {
  Json::Value root;
  Json::CharReaderBuilder builder;
  Json::CharReader *reader = builder.newCharReader();
  string jsonError;

  // Try to parse the string as Json and store the result of the pasring in a
  // boolean
  bool parsingSuccessful = reader->parse(
      buffer.c_str(), buffer.c_str() + buffer.size(), &root, &jsonError);

  // If the string is not correct Json, return
  if (!parsingSuccessful) {
    return;
  }

  const Json::Value command = root["command"];
  string cmd = command.asString();

  if (cmd == "status") {
    emit footerSetStatus(root["response"].asString().c_str());
  }

  else if (cmd == "close") {
    programActive = false;
  }

  else if (cmd == "list") {
    emit receivingClearFileList();
    // Get the array of file Names
    auto fileNames = root["names"];
    for (int i = 0; i < fileNames.size(); i++) {
      emit receivingListFile(
          QString::fromStdString(fileNames[i].asString().c_str()));
    }
  }
}

// This method is a loop which runs in a seperate thread.
// If will read the Input Pipe, which containts the string that get printed
// on stdout by the CLI/Server, and calls handleJSON with the read content
// one it reads a newline.
void QMLHandler::readPipeLoop() {
  unsigned int readOffset = 0;
  unsigned int pollCount = 0;
  struct pollfd inPipeStatus;
  inPipeStatus.fd = inpipefd[0];
  inPipeStatus.events = POLLIN;

  while (programActive) {
    poll(&inPipeStatus, 1, 100);

    if (inPipeStatus.revents & POLLIN) {
      readOffset += read(inpipefd[0], buf + readOffset, 1);

      pollCount = 0;

    } else {
      pollCount++;
    }

    if (pollCount > 9 && buf[0]) {
      buf[1024] = 0;
      buf[strlen(buf)] = 0;

      string cleanBuffer = buf + strcspn(buf, "\n") + 1;
      string receivedData = cleanBuffer.substr(0, cleanBuffer.size() - 1);

      emit log(QString::fromStdString(receivedData));
      qInfo() << QString::fromStdString(receivedData);
      handleJSON(receivedData);
      memset(buf, 0, 1024);
      pollCount = 0;
      readOffset = 0;
    }
  }
}

// ### QML Handlers ###

// Sending
void QMLHandler::onSendingSelectFileButton(QUrl url) {
  sendFileUrl = url.toLocalFile();
  emit log("File Selected: " + sendFileUrl.toString());
  emit sendingSetFileUrlText("Selected File: " + sendFileUrl.toString());
  emit sendingEnableSendButton();
}

void QMLHandler::onSendingSendFileButton() {
  QString command = "put " + sendFileUrl.toString() + "\n";
  write(outpipefd[1], command.toUtf8().constData(),
        strlen(command.toUtf8().constData()));
}

void QMLHandler::onSendingClearSelectionButton() {
  sendFileUrl = QUrl("");
  emit log("Cleared Selection");
  emit sendingSetFileUrlText("Selected File: None");
  emit sendingDisableSendButton();
}

// Receiving
void QMLHandler::onReceivingListFilesButton() {
  write(outpipefd[1], "list\n", strlen("list\n"));
}

void QMLHandler::onReceivingGetFileButton(QString fileName) {
  QString command = "get " + fileName + "\n";
  write(outpipefd[1], command.toUtf8().constData(),
        strlen(command.toUtf8().constData()));
}

// Messages
void QMLHandler::onMessagesSendButton(QString msg) { emit message(msg); }

// Settings
void QMLHandler::onSettingsSwitchServerButton() {
  emit settingsOpenSwitchServerPopup();
}

// Ip Popup
void QMLHandler::onIpPopupEnterIp(QString ip) {
  pid_t pid = 0;

  pipe(inpipefd);
  pipe(outpipefd);
  pid = fork();
  if (pid == 0) {
    // Child
    dup2(outpipefd[0], STDIN_FILENO);
    dup2(inpipefd[1], STDOUT_FILENO);
    // dup2(inpipefd[1], STDERR_FILENO);

    // ask kernel to deliver SIGTERM in case the parent dies
    prctl(PR_SET_PDEATHSIG, SIGTERM);

    // Set the path to the CLI - pass argument h (help) for now
    // TODO: Change hardcoded path
    execl("../../cli/build/ccats-cli", "ccats-cli", ip.toUtf8().constData(),
          "--machine", (char *)NULL);

    exit(1);
  }

  // TODO: Not hardcoded
  emit footerSetStatus("Connected to " + ip);

  close(outpipefd[0]);
  close(inpipefd[1]);

  std::thread(&QMLHandler::readPipeLoop, this).detach();
}

// Switch Popup
void QMLHandler::onSwitchPopupEnterIp(QString ip) {
  qInfo() << "Switching to " << ip;
}

// Footer
void QMLHandler::onFooterGetStatusButton() {
  write(outpipefd[1], "status\n", strlen("status\n"));
}