#!/bin/bash

auth_email=""                                      # The email used to login 'https://dash.cloudflare.com'
auth_method="token"                                # Set to "global" for Global API Key or "token" for Scoped API Token 
auth_key=""                                        # Your API Token or Global API Key
zone_identifier=""                                 # Can be found in the "Overview" tab of your domain
record_name=""                                     # Which record you want to be synced
proxy=false                                        # Set the proxy to true or false



###########################################
## Define date time stamp function
###########################################
function ds() {
  date +"[%F %T]"
}


###########################################
## Check if we have a public IP
###########################################
ip=$(curl -s https://api.ipify.org || curl -s https://ipv4.icanhazip.com/)

if [ "${ip}" == "" ]; then 
  message="$(ds) No public IP found."
  >&2 echo -e "${message}" >> ~/log
  exit 1
fi

###########################################
## Check and set the proper auth header
###########################################
if [ "${auth_method}" == "global" ]; then
  auth_header="X-Auth-Key:"
else
  auth_header="Authorization: Bearer"
fi

###########################################
## Seek for the A record
###########################################

echo "$(ds) Check Initiated" >> ~/log
record=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/$zone_identifier/dns_records?name=$record_name" -H "X-Auth-Email: $auth_email" -H "X-Auth-Key: $auth_key" -H "Content-Type: application/json")

###########################################
## Check if the domain has an A record
###########################################
if [[ $record == *"\"count\":0"* ]]; then
  message="$(ds) Record does not exist, perhaps create one first? (${ip} for ${record_name})"
  >&2 echo -e "${message}" >> ~/log
  exit 1
fi

###########################################
## Get existing IP
###########################################
old_ip=$(echo "$record" | grep -Po '(?<="content":")[^"]*' | head -1)
# Compare if they're the same
if [[ $ip == $old_ip ]]; then
  message="$(ds) IP ($ip) for ${record_name} has not changed."
  echo "${message}" >> ~/log
  exit 0
fi

###########################################
## Set the record identifier from result
###########################################
record_identifier=$(echo "$record" | grep -Po '(?<="id":")[^"]*' | head -1)

###########################################
## Change the IP@Cloudflare using the API
###########################################
update=$(curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/$zone_identifier/dns_records/$record_identifier" \
                     -H "X-Auth-Email: $auth_email" \
                     -H "$auth_header $auth_key" \
                     -H "Content-Type: application/json" \
              --data "{\"id\":\"$zone_identifier\",\"type\":\"A\",\"proxied\":${proxy},\"name\":\"$record_name\",\"content\":\"$ip\"}")

###########################################
## Report the status
###########################################
case "$update" in
*"\"success\":false"*)
  message="$(ds) $ip $record_name DDNS failed for $record_identifier ($ip). DUMPING RESULTS:\n$update"
  >&2 echo -e "${message}" >> ~/log
  exit 1;;
*)
  message="$(ds) $ip $record_name DDNS updated."
  echo "${message}" >> ~/log
  exit 0;;
esac