#!/bin/bash

# Collects wifi networks informations such as SSID, rate, 
# signal etc.

# EXAMPLE USAGE:
# ./wifi_scan.sh

set -e
# Debugging options:
# set -x
# set -v

# always try to rescan
nmcli device wifi rescan || true
# list connections
nmcli_output=$(nmcli -f ssid,mode,chan,rate,signal,security,in-use -t dev wifi)

# generate json
echo "[" > /tmp/.nmcli_gen_json

# make newlines the only separator
IFS=$'\n'
for line in $nmcli_output ; do
  IFS=':' read -r -a array <<< "$line"

  # remove "Mbit/s"
  rate=$(echo "${array[3]}" | sed "s/ Mbit\/s$//")
  # change in-use string to Boolean
  if [ "${array[6]}" = "*" ]; then
    inuse="true"
  else
    inuse="false"
  fi

  # parse into json
  json="{
    \"ssid\": \"${array[0]}\",
    \"mode\": \"${array[1]}\",
    \"channel\": ${array[2]},
    \"rate\": ${rate},
    \"signal\": ${array[4]},
    \"security\": \"${array[5]}\",
    \"inuse\": ${inuse}
  }"
  echo "$json", >> /tmp/.nmcli_gen_json
done

# remove last comma, change later?
perl -0777 -pi -e 's/(.*),(.*?)/\1\2/s' /tmp/.nmcli_gen_json
echo "]" >> /tmp/.nmcli_gen_json

# output json
cat /tmp/.nmcli_gen_json
rm /tmp/.nmcli_gen_json