#!/bin/bash

read input
# read config file
source flightquery.conf
# curl options
OPTS='--silent'
# sadly HTTPS isn't supported on the free plan
baseURL='http://api.aviationstack.com/v1/flights?access_key='$appKey

# get data from API
_curl() {
  result=$(curl $OPTS "$URL")
  ret=$?
  if [ "$ret" -ne 0 ]
  then
    echo "cURL error $ret when fetching."
    exit
  fi
}

_jq() {
  echo ${json} | base64 --decode | jq -r ${1}
}

_getdata() {
  # Take everything after final space as the requested input (be it an IATA airport code or IATA flight number), assuming everything before the last space is a flag
  code=$(echo $input | sed 's/.* //')
  URL="$baseURL&$queryType=$code"
  _curl
}

# TODO: refactor to remove repetitive loops

_airport() {
  _getdata
  currentTime=$(date --iso-8601=seconds)
  # Get arrivals before current time and sort (we reverse so that they're in order of most recent to least recent)
  flightsBefore=$(echo $result | jq --arg currentTime "$currentTime" '.data | map(select(.arrival.scheduled < $currentTime)) | sort_by(.arrival.scheduled) | reverse')
  # Get arrivals after current time and sort
  flightsAfter=$(echo $result | jq --arg currentTime "$currentTime" '.data | map(select(.arrival.scheduled > $currentTime)) | sort_by(.arrival.scheduled)')

  # Build output string of the two arrivals preceeding the current time
  for i in {0..1}
  do
    # Get origin/destination, airline and IATA flight number
    if [[ $direction == "Origin" ]]
    then
      airport=$(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].departure.airport')
    else
      airport=$(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].arrival.airport')
    fi
    airline=$(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].airline.name')
    flightIATA=$(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].flight.iata')

    # Get departure and takeoff times using actual or estimated times where available or falling back to scheduled if not.
    if [[ $(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].departure.actual') != "null" ]]
    then
      takeoff=$(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].departure.actual')
    elif [[ $(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].departure.estimated') != "null" ]]
    then
      takeoff=$(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].departure.estimated')
    else
      takeoff=$(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].departure.scheduled')
    fi

    if [[ $(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].arrival.actual') != "null" ]]
    then
      landing=$(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].arrival.actual')
    elif [[ $(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].arrival.estimated') != "null" ]]
    then
      landing=$(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].arrival.estimated')
    else
      landing=$(echo $flightsBefore | jq -r --arg i $i '.[$i | tonumber].arrival.scheduled')
    fi

    # Append to $output
    output="$output $airline $flightIATA $direction: $airport Takeoff: $(date -d $takeoff +"%d/%m/%Y %H:%M") Landed: $(date -d $landing +"%d/%m/%Y %H:%M") |"
  done

  # Build output string of the three arrivals immediately after the current time
  for i in {0..2}
  do
    # Get origin/destination, airline and IATA flight number
    origin=$(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].departure.airport')
    airline=$(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].airline.name')
    flightIATA=$(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].flight.iata')

    # Get departure and takeoff times using actual or estimated times where available or falling back to scheduled if not.
    if [[ $(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].departure.actual') != "null" ]]
    then
      takeoff=$(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].departure.actual')
    elif [[ $(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].departure.estimated') != "null" ]]
    then
      takeoff=$(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].departure.estimated')
    else
      takeoff=$(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].departure.scheduled')
    fi

    if [[ $(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].arrival.actual') != "null" ]]
    then
      landing=$(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].arrival.actual')
    elif [[ $(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].arrival.estimated') != "null" ]]
    then
      landing=$(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].arrival.estimated')
    else
      landing=$(echo $flightsAfter | jq -r --arg i $i '.[$i | tonumber].arrival.scheduled')
    fi

    # Append to $output
    output="$output $airline $flightIATA Origin: $origin Takeoff: $(date -d $takeoff +"%d/%m/%Y %H:%M") Landing: $(date -d $landing +"%d/%m/%Y %H:%M") |"
  done

  # remove trailing pipe
  output=$(echo $output | sed '$s/|$//')
  echo $output
  exit
}

_flight() {
  _getdata
  airline=$(echo $result | jq -r '.data[0].airline.name')
  origin=$(echo $result | jq -r '.data[0].departure.iata')
  takeoffSched=$(echo $result | jq -r '.data[0].departure.scheduled')
  takeoffEst=$(echo $result | jq -r '.data[0].departure.estimated')
  takeoffActual=$(echo $result | jq -r '.data[0].departure.actual')
  takeoffDelay=$(echo $result | jq -r '.data[0].departure.delay')
  destination=$(echo $result | jq -r '.data[0].arrival.iata')
  landingSched=$(echo $result | jq -r '.data[0].arrival.scheduled')
  landingEst=$(echo $result | jq -r '.data[0].arrival.estimated')
  landingActual=$(echo $result | jq -r '.data[0].arrival.actual')
  landingDelay=$(echo $result | jq -r '.data[0].arrival.delay')

  # Build output string giving actual or estimated times and delays where available.
  output="$airline - Origin: $origin "
  if [[ "$takeoffActual" != "null" ]]
  then
    output="$output $(date -d $takeoffActual +"%d/%m/%Y %H:%M")"
  elif [[ "$takeoffEst" != "null" ]]
  then
    output="$output $(date -d $takeoffEst +"%d/%m/%Y %H:%M")"
  else
    output="$output $(date -d $takeoffSched +"%d/%m/%Y %H:%M")"
  fi

  if [[ "$takeoffDelay" != "null" ]]
  then
    output="$output Delay: $takeoffDelay mins"
  fi

  output="$output Dest: $destination"
  if [[ "$landingActual" != "null" ]]
  then
    output="$output $(date -d $landingActual +"%d/%m/%Y %H:%M")"
  elif [[ "$landingEst" != "null" ]]
  then
    output="$output $(date -d $landingEst +"%d/%m/%Y %H:%M")"
  else
    output="$output $(date -d $landingSched +"%d/%m/%Y %H:%M")"
  fi

  if [[ "$landingDelay" != "null" ]]
  then
    output="$output Delay: $landingDelay mins"
  fi

  echo $output
}

_help() {
  echo "Usage: !flight [option] [flight/airport]. Options: -h help, -d departures [IATA airport code], -a arrivals [IATA airport code], -s source. If no option is set then you must provide an IATA flight number e.g. BA2775."
}

if [[ ${input} == "-h" ]] || [[ ${input} == "--help" ]] || [[ -z $input ]]
then
  _help
elif [[ ${input} == "--source" ]] || [[ ${input} == "-s" ]]
then
  # TODO add real source
  echo "https://www.blatech.co.uk/ars/flight-query"
  exit 0
elif [[ ${input} =~ "-a" ]] || [[ ${input} =~ "--arrivals" ]]
then
  queryType="arr_iata"
  direction="Origin"
  _airport
elif [[ ${input} =~ "-d" ]] || [[ ${input} =~ "--departures" ]]
then
  direction="Destination"
  queryType="dep_iata"
  _airport
# if it doesn't match an option then it's probably a specific plane
else
  queryType="flight_iata"
  _flight
fi