#!/bin/bash

# TODO: check & update localip in raspiblitz info for display (only write on change)

# This script runs on after start in background
# as a service and gets restarted on failure
# it runs ALMOST every seconds

# INFOFILE - state data from bootstrap
infoFile="/home/admin/raspiblitz.info"

# CONFIGFILE - configuration of RaspiBlitz
configFile="/mnt/hdd/raspiblitz.conf"

# LOGS see: sudo journalctl -f -u background

# Check if HDD contains configuration
configExists=$(ls ${configFile} | grep -c '.conf')
if [ ${configExists} -eq 1 ]; then
    source ${configFile}
else
    source ${infoFile}
fi

echo "_background.sh STARTED"

# global vars
blitzTUIHeartBeatLine=""
blitzTUIRestarts=0

counter=0
while [ 1 ]
do

  ###############################
  # Prepare this loop
  ###############################

  # count up
  counter=$(($counter+1))

  # limit counter to max seconds per week:
  # 604800 = 60sec * 60min * 24hours * 7days
  if [ ${counter} -gt 604800 ]; then
    counter=0
    echo "counter zero reset"
  fi

  # gather the uptime seconds
  upSeconds=$(cat /proc/uptime | grep -o '^[0-9]\+')

  # source info file fresh on every loop
  source ${infoFile} 2>/dev/null

  ####################################################
  # SKIP BACKGROUND TASK LOOP ON CERTAIN SYSTEM STATES
  # https://github.com/rootzoll/raspiblitz/issues/160
  ####################################################

  if [ "${state}" == "" ] || [ "${state}" == "copysource" ] || [ "${state}" == "copytarget" ]; then
    echo "skipping background loop (${counter}) - state(${state})"
    sleep 1
    continue
  fi

  ####################################################
  # CHECK IF LOCAL IP CHANGED
  ####################################################
  oldLocalIP="${localip}";
  source <(/home/admin/config.scripts/internet.sh status)
  if [ "${oldLocalIP}" != "${localip}" ]; then
    echo "local IP changed old(${oldLocalIP}) new(${localip}) - updating in raspiblitz.info"
    sed -i "s/^localip=.*/localip='${localip}'/g" ${infoFile}
  fi

  ####################################################
  # SKIP REST OF THE TASKS IF STILL IN SETUP PHASE
  ####################################################

  if [ "${setupPhase}" != "done" ]; then
    echo "skipping rest of tasks because still in setupPhase(${setupPhase})"
    sleep 1
    continue
  fi

  ####################################################
  # RECHECK DHCP-SERVER 
  # https://github.com/rootzoll/raspiblitz/issues/160
  ####################################################

  # every 5 minutes
  recheckDHCP=$((($counter % 300)+1))
  if [ ${recheckDHCP} -eq 1 ]; then
    echo "*** RECHECK DHCP-SERVER  ***"

    # get the local network IP
    localip=$(hostname -I | awk '{print $1}')
    echo "localip(${localip})"

    # detect a missing DHCP config 
    if [ "${localip:0:4}" = "169." ]; then
      echo "Missing DHCP detected ... trying emergency reboot"
      sudo /home/admin/config.scripts/blitz.shutdown.sh reboot
    else
      echo "DHCP OK"
    fi

  fi

  ####################################################
  # CHECK FOR UNDERVOLTAGE REPORTS
  # every 1 hour scan for undervoltage reports
  ####################################################
  recheckUndervoltage=$(($counter % 3600))
  if [ ${recheckUndervoltage} -eq 1 ]; then
    echo "*** RECHECK UNDERVOLTAGE ***"
    countReports=$(sudo cat /var/log/syslog | grep -c "Under-voltage detected!")
    echo "${countReports} undervoltage reports found in syslog"
    if ! grep -Eq "^undervoltageReports=" ${infoFile}; then
      # write new value to info file
      undervoltageReports="${countReports}"
      echo "undervoltageReports=${undervoltageReports}" >> ${infoFile}
    else
      # update value in info file
      sed -i "s/^undervoltageReports=.*/undervoltageReports=${countReports}/g" ${infoFile}
    fi
  fi

  ####################################################
  # RECHECK PUBLIC IP
  #
  # when public IP changes
  #  -  restart bitcoind with new IP
  #  -  restart LND with new IP (if autounlock is enabled)
  #  -  restart BTCRPCexplorer if enabled in config or running)
  ####################################################

  # every 15min - not too often
  # because its a ping to external service
  recheckPublicIP=$((($counter % 900)+1))
  # prevent when lndAddress is set
  if [ ${#lndAddress} -gt 3 ]; then
    recheckPublicIP=0
  fi

  # prevent also when runBehindTor is on
  if [ "${runBehindTor}" = "1" ] || [ "${runBehindTor}" = "on" ]; then
    recheckPublicIP=0
  fi

  updateDynDomain=0
  if [ ${recheckPublicIP} -eq 1 ]; then
    echo "*** RECHECK PUBLIC IP ***"

    # execute only after setup when config exists
    if [ ${configExists} -eq 1 ]; then
      publicIPChanged=$(/home/admin/config.scripts/internet.sh update-publicip | grep -c 'ip_changed=1')
    fi

    # check if changed
    if [ ${publicIPChanged} -gt 0 ]; then

      echo "*** change of public IP detected ***"
      echo "  old: ${publicIP}"
      # refresh data
      source /mnt/hdd/raspiblitz.conf
      echo "  new: ${publicIP}"

      # if we run on IPv6 only, the global IPv6 address at the current network device (e.g: eth0) is the public IP
      if [ "${ipv6}" = "on" ]; then
        # restart bitcoind as the global IP is stored in the node configuration
        # and we will get more connections if this matches our real IP address
        # otherwise the bitcoin-node connections will slowly decline 
        echo "IPv6 only is enabled => restart bitcoind to pickup up new publicIP as local IP"
        sudo systemctl stop bitcoind
        sleep 3
        sudo systemctl start bitcoind

        # if BTCRPCexplorer is currently running 
        # it needs to be restarted to pickup the new IP for its "Node Status Page"
        # but this is only needed in IPv6 only mode 
        breIsRunning=$(sudo systemctl status btc-rpc-explorer 2>/dev/null | grep -c 'active (running)')
        if [ ${breIsRunning} -eq 1 ]; then
          echo "BTCRPCexplorer is running => restart BTCRPCexplorer to pickup up new publicIP for the bitcoin node"
          sudo systemctl stop btc-rpc-explorer
          sudo systemctl start btc-rpc-explorer
        else 
          echo "new publicIP but no BTCRPCexplorer restart because not running"
        fi 

      else
        echo "IPv6 only is OFF => no need to restart bitcoind nor BTCRPCexplorer"
      fi 

      # only restart LND if auto-unlock is activated
      if [ "${autoUnlock}" = "on" ]; then
        echo "restart LND to pickup up new publicIP"
        sudo systemctl stop lnd
        sudo systemctl start lnd
      else
        echo "new publicIP but no LND restart because no auto-unlock"
      fi

      # trigger update if dynamic domain (if set)
      updateDynDomain=1

    else
        echo "public IP has not changed"
    fi

  fi

  ###############################
  # Blockchain Sync Monitor
  ###############################

  # check every 1min
  recheckSync=$(($counter % 60))
  if [ ${recheckSync} -eq 1 ]; then
    source <(sudo /home/admin/config.scripts/network.monitor.sh peer-status)
    echo "Blockchain Sync Monitoring: peers=${peers}"
    if [ "${peers}" == "0" ] && [ "${running}" == "1" ]; then
      echo "Blockchain Sync Monitoring: ZERO PEERS DETECTED .. doing out-of-band kickstart"
      sudo /home/admin/config.scripts/network.monitor.sh peer-kickstart
    fi
  fi

  ###############################
  # BlitzTUI Monitoring
  ###############################

  # check every 30sec
  recheckBlitzTUI=$(($counter % 30))
  if [ "${touchscreen}" == "1" ] && [ ${recheckBlitzTUI} -eq 1 ]; then
    echo "BlitzTUI Monitoring Check"
    if [ -d "/var/cache/raspiblitz" ]; then
      latestHeartBeatLine=$(sudo tail -n 300 /var/cache/raspiblitz/pi/blitz-tui.log | grep beat | tail -n 1)
    else
      latestHeartBeatLine=$(sudo tail -n 300 /home/pi/blitz-tui.log | grep beat | tail -n 1)
    fi
    if [ ${#blitzTUIHeartBeatLine} -gt 0 ]; then
      #echo "blitzTUIHeartBeatLine(${blitzTUIHeartBeatLine})"
      #echo "latestHeartBeatLine(${latestHeartBeatLine})"
      if [ "${blitzTUIHeartBeatLine}" == "${latestHeartBeatLine}" ]; then
        echo "FAIL - still no new heart beat .. restarting BlitzTUI"
        blitzTUIRestarts=$(($blitzTUIRestarts +1))
        if [ $(sudo cat /home/admin/raspiblitz.info | grep -c 'blitzTUIRestarts=') -eq 0 ]; then
          echo "blitzTUIRestarts=0" >> /home/admin/raspiblitz.info
        fi
        sudo sed -i "s/^blitzTUIRestarts=.*/blitzTUIRestarts=${blitzTUIRestarts}/g" /home/admin/raspiblitz.info
        sudo init 3 ; sleep 2 ; sudo init 5
      fi
    else
      echo "blitzTUIHeartBeatLine is empty - skipping check"
    fi
    blitzTUIHeartBeatLine="${latestHeartBeatLine}"
  fi
  
  ###############################
  # SCB Monitoring
  ###############################

  # check every 1min
  recheckSCB=$(($counter % 60))
  if [ ${recheckSCB} -eq 1 ]; then
    #echo "SCB Monitoring ..."
    source ${configFile}
    # check if channel.backup exists
    scbPath=/mnt/hdd/lnd/data/chain/${network}/${chain}net/channel.backup
    scbExists=$(sudo ls $scbPath 2>/dev/null | grep -c 'channel.backup')
    if [ ${scbExists} -eq 1 ]; then
      # timestamp backup filename
      timestampedFileName=channel-$(date "+%Y%m%d-%H%M%S").backup
      localBackupDir=/home/admin/backups/scb
      localBackupPath=${localBackupDir}/channel.backup
      localTimestampedPath=${localBackupDir}/${timestampedFileName}

      #echo "Found Channel Backup File .. check if changed .."
      md5checksumORG=$(sudo md5sum $scbPath 2>/dev/null | head -n1 | cut -d " " -f1)
      md5checksumCPY=$(sudo md5sum $localBackupPath 2>/dev/null | head -n1 | cut -d " " -f1)
      if [ "${md5checksumORG}" != "${md5checksumCPY}" ]; then
        echo "--> Channel Backup File changed"

        # make copy to sd card (as local basic backup)
        sudo mkdir -p /home/admin/backups/scb/ 2>/dev/null
        sudo cp $scbPath $localBackupPath
        sudo cp $scbPath $localTimestampedPath
        sudo cp $scbPath /boot/channel.backup
        echo "OK channel.backup copied to '${localBackupPath}' and '{$localTimestampedPath}' and '/boot/channel.backup'"

        # check if a additional local backup target is set
        # see ./config.scripts/blitz.backupdevice.sh
        if [ "${localBackupDeviceUUID}" != "" ] && [ "${localBackupDeviceUUID}" != "off" ]; then

          # check if device got mounted on "/mnt/backup" (gets mounted by _bootstrap.sh)
          backupDeviceExists=$(df | grep -c "/mnt/backup")
          if [ ${backupDeviceExists} -gt 0 ]; then

            echo "--> Additional Local Backup Device"
            sudo cp ${localBackupPath} /mnt/backup/
            sudo cp ${localTimestampedPath} /mnt/backup/

            # check results
            result=$?
            if [ ${result} -eq 0 ]; then
              echo "OK - Successful Copy to additional Backup Device"
            else
              echo "FAIL - Copy to additional Backup Device exited with ${result}"
            fi

          else
            echo "FAIL - BackupDrive mount - check if device is connected & UUID is correct" >> $logFile
          fi
        fi

        # check if a SCP backup target is set
        # parameter in raspiblitz.conf:
        # scpBackupTarget='[USER]@[SERVER]:[DIRPATH-WITHOUT-ENDING-/]'
        # optionally a custom option string for the scp command can be set with
        # scpBackupOptions='[YOUR-CUSTOM-OPTIONS]'
        # On target server add the public key of your RaspiBlitz to the authorized_keys for the user
        # https://www.linode.com/docs/security/authentication/use-public-key-authentication-with-ssh/
        if [ ${#scpBackupTarget} -gt 0 ]; then
          echo "--> Offsite-Backup SCP Server"
          if [ "${scpBackupOptions}" == "" ]; then
            scpBackupOptions="-o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null"
          fi 
          # its ok to ignore known host, because data is encrypted (worst case of MiM would be: no offsite channel backup)
          # but its more likely that without ignoring known host, script might not run thru and that way: no offsite channel backup
          sudo scp ${scpBackupOptions} ${localBackupPath} ${scpBackupTarget}/
          sudo scp ${scpBackupOptions} ${localTimestampedPath} ${scpBackupTarget}/
          result=$?
          if [ ${result} -eq 0 ]; then
            echo "OK - SCP Backup exited with 0"
          else
            echo "FAIL - SCP Backup exited with ${result}"
          fi
        fi

        # check if a DropBox backup target is set
        # parameter in raspiblitz.conf:
        # dropboxBackupTarget='[DROPBOX-APP-OAUTH2-TOKEN]'
        # see dropbox setup: https://gist.github.com/vindard/e0cd3d41bb403a823f3b5002488e3f90
        if [ ${#dropboxBackupTarget} -gt 0 ]; then
          echo "--> Offsite-Backup Dropbox"
          source <(sudo /home/admin/config.scripts/dropbox.upload.sh upload ${dropboxBackupTarget} ${localBackupPath})
          source <(sudo /home/admin/config.scripts/dropbox.upload.sh upload ${dropboxBackupTarget} ${localTimestampedPath})
          if [ ${#err} -gt 0 ]; then
            echo "FAIL -  ${err}"
            echo "${errMore}"
          else
            echo "OK - ${upload}"
          fi
        fi

      #else
      #  echo "Channel Backup File not changed."
      fi
    #else
    #  echo "No Channel Backup File .."
    fi
  fi

  ###############################
  # SUBSCRIPTION RENWES
  ###############################

  # check every 20min
  recheckSubscription=$((($counter % 1200)+1))
  if [ ${recheckSubscription} -eq 1 ]; then
    # IP2TOR subscriptions (that will need renew in next 20min = 1200 secs)
    sudo -u admin /home/admin/config.scripts/blitz.subscriptions.ip2tor.py subscriptions-renew 1800
  fi

  ###############################
  # RAID data check (BRTFS)
  ###############################
  # see https://github.com/rootzoll/raspiblitz/issues/360#issuecomment-467698260

  # check every hour
  recheckRAID=$((($counter % 3600)+1))
  if [ ${recheckRAID} -eq 1 ]; then
    
    # check if raid is active
    source <(sudo /home/admin/config.scripts/blitz.datadrive.sh status)
    if [ ${isRaid} -eq 1 ]; then

      # will run in the background
      echo "STARTING BTRFS RAID DATA CHECK ..."
      sudo btrfs scrub start /mnt/hdd/

    fi

  fi

  ###############################
  # LND AUTO-UNLOCK
  ###############################

  # check every 10secs
  recheckAutoUnlock=$((($counter % 10)+1))
  if [ ${recheckAutoUnlock} -eq 1 ]; then

    # check if auto-unlock feature if activated
    if [ "${autoUnlock}" = "on" ]; then

      # check if lnd is locked
      source <(/home/admin/config.scripts/lnd.unlock.sh status)
      if [ "${locked}" != "0" ]; then

        echo "STARTING AUTO-UNLOCK ..."
        sudo /home/admin/config.scripts/lnd.unlock.sh
        
      fi
    fi
  fi

  ###############################
  # UPDATE DYNAMIC DOMAIN
  # like afraid.org
  # ! experimental
  ###############################

  # if not activated above, update every 6 hours
  if [ ${updateDynDomain} -eq 0 ]; then
    # dont +1 so that it gets executed on first loop
    updateDynDomain=$(($counter % 21600))
  fi
  if [ ${updateDynDomain} -eq 1 ]; then
    echo "*** UPDATE DYNAMIC DOMAIN ***"
    # check if update URL for dyn Domain is set
    if [ ${#dynUpdateUrl} -gt 0 ]; then
      /home/admin/config.scripts/internet.dyndomain.sh update
    else
      echo "'dynUpdateUrl' not set in ${configFile}"
    fi
  fi

  ####################################################
  # CHECK FOR END OF IBD (self validation)
  ####################################################

  # check every 60secs
  recheckIBD=$((($counter % 60)+1))
  if [ ${recheckIBD} -eq 1 ]; then
    # check if flag exists (got created on 50syncHDD.sh)
    flagExists=$(ls /mnt/hdd/${network}/blocks/selfsync.flag 2>/dev/null | grep -c "selfsync.flag")
    if [ ${flagExists} -eq 1 ]; then
      source <(/home/admin/config.scripts/network.aliases.sh getvars)
      finishedIBD=$($bitcoincli_alias getblockchaininfo | grep "initialblockdownload" | grep -c "false")
      if [ ${finishedIBD} -eq 1 ]; then

        echo "CHECK FOR END OF IBD --> reduce RAM, check TOR and restart ${network}d"

        # remove flag
        sudo rm /home/admin/selfsync.flag

        # stop bitcoind
        sudo systemctl stop ${network}d

        # set dbcache back to normal (to give room for other apps)
        kbSizeRAM=$(sudo cat /proc/meminfo | grep "MemTotal" | sed 's/[^0-9]*//g')
        if [ ${kbSizeRAM} -gt 1500000 ]; then
          echo "Detected RAM >1GB --> optimizing ${network}.conf"
          sudo sed -i "s/^dbcache=.*/dbcache=512/g" /mnt/hdd/${network}/${network}.conf
        else
          echo "Detected RAM 1GB --> optimizing ${network}.conf"
          sudo sed -i "s/^dbcache=.*/dbcache=128/g" /mnt/hdd/${network}/${network}.conf
        fi

        # if TOR was activated during setup make sure bitcoin runs behind TOR latest from now on
        if [ "${runBehindTor}" = "on" ]; then
          echo "TOR is ON -> make sure bitcoin is running behind TOR after IBD"
          sudo /home/admin/config.scripts/internet.tor.sh btcconf-on
        else
           echo "TOR is OFF after IBD"
        fi

        # restart bitcoind
        sudo systemctl start ${network}d

      fi
    fi
  fi

  ###############################
  # Set the address API use for BTC-RPC-Explorer depending on Electrs status
  ###############################

  # check every 10 minutes
  electrsExplorer=$((($counter % 600)+1))
  if [ ${electrsExplorer} -eq 1 ]; then
    if [ "${BTCRPCexplorer}" = "on" ]; then
      /home/admin/config.scripts/bonus.electrsexplorer.sh
    fi
  fi

  ###############################
  # Prepare next loop
  ###############################

  # sleep 1 sec
  sleep 1

done