const { spawn } = require('child_process');
const targz = require('targz');

const DBUS_MONITOR_LEGACY =
    'dbus-monitor --system | grep "sendMessage\\|ReceivedMessage" -A7 \n';
const DBUS_MONITOR_NEW =
    'dbus-monitor --system | grep "member=execute\\|method return" -A7 \n';

// Capture state for all scripts
var g_capture_state = 'not started';
var g_capture_mode = 'live';

// For capturing IPMI requests live
var g_dbus_monitor_cmd = '';

// For tracking transfer
var g_hexdump = '';
var g_hexdump_received_size = 0;
var g_hexdump_total_size = 0;

function currTimestamp() {
  var tmp = new Date();
  return (tmp.getTime() + tmp.getTimezoneOffset() * 60000) / 1000;
}

var g_child;
var g_rz;

var g_capture_live = true;
var g_dbus_capture_tarfile_size = 0;

function ParseHexDump(hd) {
  let ret = [];
  let lines = hd.split('\n');
  let tot_size = 0;
  for (let i = 0; i < lines.length; i++) {
    const line = lines[i].trimEnd();
    const sp = line.split(' ');
    if (line.length < 1) continue;
    if (sp.length < 1) continue;

    for (let j = 1; j < sp.length; j++) {
      let b0 = sp[j].slice(2);
      let b1 = sp[j].slice(0, 2);
      b0 = parseInt(b0, 16);
      b1 = parseInt(b1, 16);
      ret.push(b0);
      ret.push(b1);
    }

    console.log('[' + line + ']')

    {
      tot_size = parseInt(sp[0], 16);
      console.log('File size: ' + tot_size + ' ' + sp[0]);
    }
  }
  ret = ret.slice(0, tot_size);
  return new Buffer(ret);
}

function SaveHexdumpToFile(hd, file_name) {
  const buf = ParseHexDump(hd);
  fs.writeFileSync(file_name, buf)
}

// Delimiters: ">>>>>>" and "<<<<<<"
function ExtractMyDelimitedStuff(x, parse_as = undefined) {
  let i0 = x.lastIndexOf('>>>>>>'), i1 = x.lastIndexOf('<<<<<<');
  if (i0 != -1 && i1 != -1) {
    let ret = x.substr(i0 + 6, i1 - i0 - 6);
    if (parse_as == undefined)
      return ret;
    else if (parse_as == 'int')
      return parseInt(ret);
  } else
    return null;
}

function streamWrite(stream, chunk, encoding = 'utf8') {
  return new Promise((resolve, reject) => {
    const errListener = (err) => {
      stream.removeListener('error', errListener);
      reject(err);
    };
    stream.addListener('error', errListener);
    const callback = () => {
      stream.removeListener('error', errListener);
      resolve(undefined);
    };
    stream.write(chunk, encoding, callback);
  });
}

function ExtractTarFile() {
  const tar_file = 'DBUS_MONITOR.tar.gz';
  const target = '.';
  targz.decompress({src: tar_file, dest: target}, function(err) {
    if (err) {
      console.log('Error decompressing .tar.gz file:' + err);
    }
    // Attempt to load even if error occurs
    // example error: "Error decompressing .tar.gz file:Error: incorrect data check"
    console.log('Done! will load file contents');
    if (g_capture_mode == 'staged') {
      fs.readFile('./DBUS_MONITOR', {encoding: 'utf-8'}, (err, data) => {
        if (err) {
          console.log('Error in readFile: ' + err);
        } else {
          ParseIPMIDump(data);
        }
      });
    } else if (g_capture_mode == 'staged2') {
      OpenDBusPcapFile('./DBUS_MONITOR');
    }
  });
}

function OnCaptureStart() {
  switch (g_capture_state) {
    case 'not started':
      capture_info.textContent = 'dbus-monitor running on BMC';
      break;
    default:
      break;
  }
}

function OnCaptureStop() {
  btn_start_capture.disabled = false;
  select_capture_mode.disabled = false;
  text_hostname.disabled = false;
  g_capture_state = 'not started';
}

async function OnTransferCompleted() {
  setTimeout(function() {
    console.log('OnTransferCompleted');
    g_child.kill('SIGINT');
  }, 5000);

  capture_info.textContent = 'Loaded the capture file';
  OnCaptureStop();
  ExtractTarFile();
}

// Example output from stderr:
// ^M Bytes received:    2549/   2549   BPS:6370
async function LaunchRZ() {
  // On the Host

  // Remove existing file
  const file_names = ['DBUS_MONITOR', 'DBUS_MONITOR.tar.gz'];
  try {
    for (let i = 0; i < 2; i++) {
      const fn = file_names[i];
      if (fs.existsSync(fn)) {
        fs.unlinkSync(fn);  // unlink is basically rm
        console.log('Removed file: ' + fn);
      }
    }
  } catch (err) {
  }

  g_rz = spawn(
      'screen', ['rz', '-a', '-e', '-E', '-r', '-w', '32767'], {shell: false});
  g_rz.stdout.on('data', (data) => {
    console.log('[rz] received ' + data.length + ' B');
    console.log(data);
    console.log(data + '');
    // data = MyCorrection(data);
    if (data != undefined) g_child.stdin.write(data);
  });
  g_rz.stderr.on('data', (data) => {
    console.log('[rz] error: ' + data);
    let s = data.toString();
    let idx = s.lastIndexOf('Bytes received:');
    if (idx != -1) {
      capture_info.textContent = s.substr(idx);
    }
    if (data.indexOf('Transfer complete') != -1) {
      OnTransferCompleted();
    } else if (data.indexOf('Transfer incomplete') != -1) {
      // todo: retry transfer
      // Bug info
      // Uncaught Error [ERR_STREAM_WRITE_AFTER_END]: write after end
      // at writeAfterEnd (_stream_writable.js:253)
      // at Socket.Writable.write (_stream_writable.js:302)
      // at Socket.<anonymous> (ipmi_capture.js:317)
      // at Socket.emit (events.js:210)
      // at addChunk (_stream_readable.js:308)
      // at readableAddChunk (_stream_readable.js:289)
      // at Socket.Readable.push (_stream_readable.js:223)
      // at Pipe.onStreamRead (internal/stream_base_commons.js:182)
      capture_info.textContent = 'Transfer incomplete';
    }
  });
  await Promise.all(
      [g_rz.stdin.pipe(g_child.stdout), g_rz.stdout.pipe(g_child.stdin)]);
}

function ClearAllPendingTimeouts() {
  var id = setTimeout(function() {}, 0);
  for (; id >= 0; id--) clearTimeout(id);
}

function StartDbusMonitorFileSizePollLoop() {
  QueueDbusMonitorFileSize(5);
}

function QueueDbusMonitorFileSize(secs = 5) {
  setTimeout(function() {
    g_child.stdin.write(
        'a=`ls -l /run/initramfs/DBUS_MONITOR | awk \'{print $5}\'` ; echo ">>>>>>$a<<<<<<"  \n\n\n\n');
    QueueDbusMonitorFileSize(secs);
  }, secs * 1000);
}

function StopCapture() {
  switch (g_capture_mode) {
    case 'live':
      g_child.stdin.write('\x03 ');
      g_capture_state = 'stopping';
      capture_info.textContent = 'Ctrl+C sent to BMC console';
      break;
    case 'staged':
      ClearAllPendingTimeouts();
      g_child.stdin.write(
          'echo ">>>>>>" && killall busctl && echo "<<<<<<" \n\n\n\n');
      g_capture_state = 'stopping';
      capture_info.textContent = 'Stopping dbus-monitor';
    case 'staged2':
      g_hexdump_received_size = 0;
      g_hexdump_total_size = 0;
      ClearAllPendingTimeouts();
      g_child.stdin.write(
          'echo ">>>>>>" && killall busctl && echo "<<<<<<" \n\n\n\n');
      g_capture_state = 'stopping';
      capture_info.textContent = 'Stopping busctl';
      break;
  }
}

function QueueBMCConsoleHello(secs = 3) {
  setTimeout(function() {
    try {
      if (g_capture_state == 'not started') {
        console.log('Sending hello <cr> to the BMC');
        g_child.stdin.write('\n');
        QueueBMCConsoleHello(secs);
      }
    } catch (err) {
      console.log('g_child may have ended as intended');
    }
  }, secs * 1000);
}

// The command line needed to access the BMC. The expectation is
// executing this command brings the user to the BMC's console.
function GetCMDLine() {
  let v = text_hostname.value.split(' ');
  return [v[0], v.slice(1, v.length)];
}

async function StartCapture(host) {
  // Disable buttons
  HideWelcomeScreen();
  ShowIPMITimeline();
  ShowNavigation();
  let args = GetCMDLine();
  btn_start_capture.disabled = true;
  select_capture_mode.disabled = true;
  text_hostname.disabled = true;
  capture_info.textContent = 'Contacting BMC console: ' + args.toString();

  // On the B.M.C.
  let last_t = currTimestamp();
  let attempt = 0;
  console.log('Args: ' + args);
  g_child = spawn(args[0], args[1], {shell: true});
  g_child.stdout.on('data', async function(data) {
    QueueBMCConsoleHello();

    var t = currTimestamp();
    {
      switch (g_capture_state) {
        case 'not started':  // Do nothing
          break;
        case 'started':
          attempt++;
          console.log('attempt ' + attempt);
          g_child.stdin.write('echo "haha" \n');
          await streamWrite(g_child.stdin, 'whoami \n');
          let idx = data.indexOf('haha');
          if (idx != -1) {
            ClearAllPendingTimeouts();
            OnCaptureStart();  // Successfully logged on, start

            if (g_capture_mode == 'live') {
              g_child.stdin.write(
                  '\n\n' +
                  'a=`pidof btbridged`;b=`pidof kcsbridged`;c=`pidof netipmid`;' +
                  'echo ">>>>>>$a,$b,$c<<<<<<"\n\n');
              g_capture_state = 'determine bridge daemon';
            } else {
              g_capture_state = 'dbus monitor start';
            }
            capture_info.textContent = 'Reached BMC console';

          } else {
            console.log('idx=' + idx);
          }
          break;
        case 'determine bridge daemon': {
          const abc = ExtractMyDelimitedStuff(data.toString());
          if (abc == null) break;
          const sp = abc.split(',');
          if (parseInt(sp[0]) >= 0) {  // btbridged, legacy interface
            g_dbus_monitor_cmd = DBUS_MONITOR_LEGACY;
            console.log('The BMC is using btbridged.');
          } else if (parseInt(sp[1]) >= 0) {  // new iface
            g_dbus_monitor_cmd = DBUS_MONITOR_NEW;
            console.log('The BMC is using kcsbridged.');
          } else if (parseInt(sp[2]) >= 0) {
            g_dbus_monitor_cmd = DBUS_MONITOR_NEW;
            console.log('The BMC is using netipmid.');
          } else {
            console.log('Cannot determine the IPMI bridge daemon\n')
            return;
          }
          g_capture_state = 'dbus monitor start';
          break;
        }
        case 'dbus monitor start':
          if (g_capture_mode == 'live') {
            // It would be good to make sure the console bit rate is greater
            // than the speed at which outputs are generated.
            //            g_child.stdin.write("dbus-monitor --system | grep
            //            \"sendMessage\\|ReceivedMessage\" -A7 \n")
            ClearAllPendingTimeouts();
            g_child.stdin.write(
                'dbus-monitor --system | grep "member=execute\\|method return" -A7 \n');
            capture_info.textContent = 'Started dbus-monitor for live capture';
          } else {
            //            g_child.stdin.write("dbus-monitor --system | grep
            //            \"sendMessage\\|ReceivedMessage\" -A7 >
            //            /run/initramfs/DBUS_MONITOR & \n\n\n")
            ClearAllPendingTimeouts();
            if (g_capture_mode == 'staged') {
              g_child.stdin.write(
                  'dbus-monitor --system > /run/initramfs/DBUS_MONITOR & \n\n\n');
              capture_info.textContent =
                  'Started dbus-monitor for staged IPMI capture';
            } else if (g_capture_mode == 'staged2') {
              g_child.stdin.write(
                  'busctl capture > /run/initramfs/DBUS_MONITOR & \n\n\n');
              capture_info.textContent =
                  'Started busctl for staged IPMI + DBus capture';
            }
            StartDbusMonitorFileSizePollLoop();
          }
          g_capture_state = 'dbus monitor running';
          break;
        case 'dbus monitor running':
          if (g_capture_mode == 'staged' || g_capture_mode == 'staged2') {
            let s = data.toString();
            let tmp = ExtractMyDelimitedStuff(s, 'int');
            if (tmp != undefined) {
              let sz = Math.floor(parseInt(tmp) / 1024);
              if (!isNaN(sz)) {
                capture_info.textContent =
                    'Raw Dbus capture size: ' + sz + ' KiB';
              } else {  // This can happen if the output is cut by half & may be
                        // fixed by queuing console outputs
              }
            }
          } else {
            AppendToParseBuffer(data.toString());
            MunchLines();
            UpdateLayout();
            ComputeHistogram();
          }
          break;
        case 'dbus monitor end':  // Todo: add speed check
          let s = data.toString();
          let i0 = s.lastIndexOf('>>>>'), i1 = s.lastIndexOf('<<<<');
          if (i0 != -1 && i1 != -1) {
            let tmp = s.substr(i0 + 4, i1 - i0 - 4);
            let sz = parseInt(tmp);
            if (isNaN(sz)) {
              console.log(
                  'Error: the tentative dbus-profile dump is not found!');
            } else {
              let bps = sz / 10;
              console.log('dbus-monitor generates ' + bps + 'B per second');
            }
          }
          g_child.kill('SIGINT');
          break;
        case 'sz sending':
          console.log('[sz] Received a chunk of size ' + data.length);
          console.log(data);
          console.log(data + '');
          //          capture_info.textContent = "Received a chunk of size " +
          //          data.length
          g_rz.stdin.write(data);
          break;
        case 'stopping':
          let t = data.toString();
          if (g_capture_mode == 'live') {
            if (t.lastIndexOf('^C') != -1) {
              // Live mode
              g_child.kill('SIGINT');
              g_capture_state = 'not started';
              OnCaptureStop();
              capture_info.textContent = 'connection to BMC closed';
              // Log mode
            }
          } else if (
              g_capture_mode == 'staged' || g_capture_mode == 'staged2') {
            ClearAllPendingTimeouts();
            if (t.lastIndexOf('<<<<<<') != -1) {
              g_capture_state = 'compressing';
              g_child.stdin.write(
                  'echo ">>>>>>" && cd /run/initramfs && tar cfz DBUS_MONITOR.tar.gz DBUS_MONITOR && echo "<<<<<<" \n\n\n\n');
              capture_info.textContent = 'Compressing dbus monitor dump on BMC';
            }
          }
          break;
        case 'compressing':
          g_child.stdin.write(
              '\n\na=`ls -l /run/initramfs/DBUS_MONITOR.tar.gz | awk \'{print $5}\'` && echo ">>>>>>$a<<<<<<"   \n\n\n\n');
          g_capture_state = 'dbus_monitor size';
          capture_info.textContent = 'Obtaining size of compressed dbus dump';
          break;
        case 'dbus_monitor size':
          // Starting RZ
          let tmp = ExtractMyDelimitedStuff(data.toString(), 'int');
          if (tmp != null && !isNaN(tmp)) {  // Wait until result shows up
            g_hexdump_total_size = tmp;
            console.log(
                'dbus_monitor size tmp=' + tmp + ', ' + data.toString());

            // if (tmp != undefined) {
            //   g_dbus_capture_tarfile_size = tmp;
            //   capture_info.textContent =
            //       'Starting rz and sz, file size: ' + Math.floor(tmp / 1024)
            //       + ' KiB';
            // } else {
            //   capture_info.textContent = 'Starting rz and sz';
            // }
            // g_capture_state = 'sz start';
            // g_child.stdin.write(
            //   '\n\n\n\n' +
            //   'sz -a -e -R -L 512 -w 32767 -y
            //   /run/initramfs/DBUS_MONITOR.tar.gz\n');
            // g_capture_state = 'sz sending';
            // LaunchRZ();
            g_child.stdin.write(
                'echo ">>>>>>"; hexdump /run/initramfs/DBUS_MONITOR.tar.gz ; echo "<<<<<<"; \n');
            g_capture_state = 'test hexdump running';
            g_hexdump = new Buffer([]);
          }

          break;
        case 'test hexdump start':
          g_child.stdin.write(
              'echo ">>>>>>"; hexdump /run/initramfs/DBUS_MONITOR.tar.gz ; echo "<<<<<<"; \n');
          g_capture_state = 'test hexdump running';
          g_hexdump = new Buffer([]);
          g_hexdump_received_size = 0;
          break;
        case 'test hexdump running':
          g_hexdump += data;
          const lines = data.toString().split('\n');
          for (let j = lines.length - 1; j >= 0; j--) {
            sp = lines[j].trimEnd().split(' ');
            if (sp.length >= 1) {
              const sz = parseInt(sp[0], 16)
              if (!isNaN(sz)) {
                if (g_hexdump_received_size < sz) {
                  g_hexdump_received_size = sz;
                  capture_info.textContent = 'Receiving capture file: ' + sz +
                      ' / ' + g_hexdump_total_size + ' B';
                  break;
                }
              }
            }
          }
          if (data.includes('<<<<<<') && !data.includes('echo')) {
            g_hexdump = ExtractMyDelimitedStuff(g_hexdump);
            SaveHexdumpToFile(g_hexdump, 'DBUS_MONITOR.tar.gz');
            OnTransferCompleted();
          }
          break;
      }
      last_t = t;
    }
  });
  g_child.stderr.on('data', (data) => {
    console.log('[bmc] err=' + data);
    g_child.stdin.write('echo "haha" \n\n');
  });
  g_child.on('close', (code) => {
    console.log('return code: ' + code);
  });
}