#!/usr/bin/env bash

# Default values
SERVER=""
WARNING_LEVEL=""
CRITICAL_LEVEL=""
RSA_PUBLIC_KEY=""
USERNAME=""
PASSWORD=""

# Parse named arguments
while [[ $# -gt 0 ]]; do
  key="$1"

  case $key in
  --server)
    SERVER="$2"
    shift
    shift
    ;;
  --warning)
    WARNING_LEVEL="$2"
    shift
    shift
    ;;
  --critical)
    CRITICAL_LEVEL="$2"
    shift
    shift
    ;;
  --rsa-public-key)
    RSA_PUBLIC_KEY="$2"
    shift
    shift
    ;;
  --username)
    USERNAME="$2"
    shift
    shift
    ;;
  --password)
    PASSWORD="$2"
    shift
    shift
    ;;
  *)
    shift
    ;;
  esac
done

# Check if required arguments are provided
if [[ -z "$SERVER" ]] || [[ -z "$WARNING_LEVEL" ]] || [[ -z "$CRITICAL_LEVEL" ]]; then
  echo "Usage: $0 --server SERVER --warning WARNING_LEVEL --critical CRITICAL_LEVEL [--rsa-public-key RSA_PUBLIC_KEY] [--username USERNAME] [--password PASSWORD]"
  exit -1
fi

# Set IPERF3_PASSWORD environment variable
export IPERF3_PASSWORD="$PASSWORD"

# Run iperf3 command with optional arguments
if [[ -n "$RSA_PUBLIC_KEY" ]] && [[ -n "$USERNAME" ]]; then
  OUTPUT=$(iperf3 -c "$SERVER" -i 1 -t 10 -f m --rsa-public-key-path "$RSA_PUBLIC_KEY" --username "$USERNAME" 2>&1)
else
  OUTPUT=$(iperf3 -c "$SERVER" -i 1 -t 10 -f m 2>&1)
fi

# Check if iperf3 command failed
if [[ $? -ne 0 ]]; then
  echo "UNKNOWN - iperf3 command failed: $OUTPUT"
  exit -1
fi

# Extract the receiver bitrate
RECEIVER_BITRATE=$(echo "$OUTPUT" | grep -Eo '[0-9]+(\.[0-9]+)? Mbits/sec' | tail -1 | awk '{print $1}')

# Prepare performance data
PERFDATA="receiver_bitrate=${RECEIVER_BITRATE}mb;${WARNING_LEVEL};${CRITICAL_LEVEL};0;"

# Check the receiver bitrate against warning and critical levels
if (($(echo "$RECEIVER_BITRATE < $CRITICAL_LEVEL" | bc -l))); then
  echo "CRITICAL - Receiver Bitrate: $RECEIVER_BITRATE Mbits/sec | $PERFDATA"
  exit 2
elif (($(echo "$RECEIVER_BITRATE < $WARNING_LEVEL" | bc -l))); then
  echo "WARNING - Receiver Bitrate: $RECEIVER_BITRATE Mbits/sec | $PERFDATA"
  exit 1
else
  echo "OK - Receiver Bitrate: $RECEIVER_BITRATE Mbits/sec | $PERFDATA"
  exit 0
fi