#!/bin/bash

adguard_test_domain='check.adguard.test'

if [[ "$(uname)" == "Darwin" ]]; then
    # macOS
    local_ip=$(ifconfig | grep "inet " | grep -v 127.0.0.1 | awk '{print $2}' | head -n1)
    uptime_seconds=$(sysctl -n kern.boottime | awk '{print $4}' | sed 's/,//')
    current_time=$(date +%s)
    uptime_seconds=$((current_time - uptime_seconds))
    days=$((uptime_seconds / 86400))
    hours=$(( (uptime_seconds % 86400) / 3600 ))
    minutes=$(( (uptime_seconds % 3600) / 60 ))
    uptime="up "
    [[ $days -gt 0 ]] && uptime+="$days days, "
    [[ $hours -gt 0 ]] && uptime+="$hours hours, "
    uptime+="$minutes minutes"
else
    # Linux
    local_ip=$(hostname -I | awk '{print $1}')
    uptime=$(uptime -p)
fi

wan_info=$(curl -s --max-time 10 https://am.i.mullvad.net/json)
wan_connected=false
if [ ! -z "$wan_info" ]; then
  wan_connected=true
  wan_ip=$(echo "$wan_info" | jq -r '.ip')
  mullvad_exit_ip=$(echo "$wan_info" | jq '.mullvad_exit_ip')
  blacklisted=$(echo "$wan_info" | jq '.blacklisted.blacklisted')
else
  wan_ip="Unavailable"
  mullvad_exit_ip=false
  blacklisted=false
fi

# Check if Tailscale is installed and get IP
if command -v tailscale &> /dev/null; then
  has_tailscale=true
  tailscale_ip=$(tailscale ip -4)
  # Get Tailscale exit-node information
  ts_exitnode_output=$(tailscale exit-node list)
  # Parse exit node hostname
  if echo "$ts_exitnode_output" | grep -q 'selected'; then
    mullvad_exitnode=true
    # Extract the hostname of the selected exit node, taking only the part before any newline
    mullvad_hostname=$(echo "$ts_exitnode_output" | grep 'selected' | awk '{print $2}' | awk -F'\n' '{print $1}')
  else
    mullvad_exitnode=false
    mullvad_hostname=""
  fi
else
  has_tailscale=false
  tailscale_ip="Not installed"
  mullvad_exitnode=false
  mullvad_hostname=""
fi

nextdns_info=$(curl -sL --max-time 10 https://test.nextdns.io)
if [ -z "$nextdns_info" ]; then
  echo "Failed to fetch NextDNS status or no internet connection." >&2
  nextdns_connected=false
  nextdns_protocol=""
  nextdns_client=""
else
  nextdns_status=$(echo "$nextdns_info" | jq -r '.status')
  if [ "$nextdns_status" = "ok" ]; then
    nextdns_connected=true
    nextdns_protocol=$(echo "$nextdns_info" | jq -r '.protocol')
    nextdns_client=$(echo "$nextdns_info" | jq -r '.clientName')
  else
    nextdns_connected=false
    nextdns_protocol=""
    nextdns_client=""
  fi
fi

# Check AdGuard Home DNS
resolved_ip=$(dig +short $adguard_test_domain)
if [[ $resolved_ip =~ ^100\. ]]; then
  adguard_connected=true
  adguard_protocol="AdGuard Home"
  adguard_client="$resolved_ip"
else
  adguard_connected=false
  adguard_protocol=""
  adguard_client=""
fi

# Output JSON using jq for proper formatting and escaping
jq -n \
--arg local_ip "$local_ip" \
--argjson wan_connected "$wan_connected" \
--arg wan_ip "$wan_ip" \
--argjson has_tailscale "$has_tailscale" \
--arg tailscale_ip "$tailscale_ip" \
--argjson mullvad_exitnode "$mullvad_exitnode" \
--arg mullvad_hostname "$mullvad_hostname" \
--argjson mullvad_exit_ip "$mullvad_exit_ip" \
--argjson blacklisted "$blacklisted" \
--argjson nextdns_connected "$nextdns_connected" \
--arg nextdns_protocol "$nextdns_protocol" \
--arg nextdns_client "$nextdns_client" \
--argjson adguard_connected "$adguard_connected" \
--arg adguard_protocol "$adguard_protocol" \
--arg adguard_client "$adguard_client" \
--arg uptime "$uptime" \
'{
  local_ip: $local_ip,
  wan_connected: $wan_connected,
  wan_ip: $wan_ip,
  has_tailscale: $has_tailscale,
  tailscale_ip: $tailscale_ip,
  mullvad_exitnode: $mullvad_exitnode,
  mullvad_hostname: $mullvad_hostname,
  mullvad_exit_ip: $mullvad_exit_ip,
  blacklisted: $blacklisted,
  nextdns_connected: $nextdns_connected,
  nextdns_protocol: $nextdns_protocol,
  nextdns_client: $nextdns_client,
  adguard_connected: $adguard_connected,
  adguard_protocol: $adguard_protocol,
  adguard_client: $adguard_client,
  uptime: $uptime
}'