#! /bin/bash

# https://unix.stackexchange.com/a/423052
function find_free_port {
    comm -23 <(seq 49152 65535 | sort) <(ss -Htan | awk '{print $4}' | cut -d':' -f2 | sort -u) | shuf | head -n 1
}

# gen_webhook "REPO_URL"
#function gen_webhook {
#    echo "{ \"project\": { \"git_http_url\": \"$1\" } }"
#}

function gen_webhook() {
    export repo_url="$2"
    envsubst < "$1" 
}

# send_webhook "ENDPOINT" "PAYLOAD" "SECRET" "HEADER"
#   ENDPOINT: where to send the request
#   PAYLOAD: POST body
#   SECRET: the secret for this transaction
#   HEADER: where to store the secret
function send_webhook {
    echo "$2" > $TMPFILE

    # We can make a few attempts, just in case the webserver hasn't started yet
    n=0
    while [[ "$status" != "0" ]]; do
        if [ $n -eq 3 ]; then
            # Failed to reach server after 3 attempts
            return 1;
        fi
        # --data-binary so that newlines aren't broken
        # (otherwise, signature won't match)
        run curl --header "Content-Type: application/json" \
            --header ""$4": "$3"" \
            --request POST \
            --data-binary @$TMPFILE \
            -s -w "%{http_code}" \
            "$1"
        # Requested succeeded, break out of loop
        if [ $status -eq 0 ]; then
            echo "$output"
            if [[ ! "$output" = 200 ]]; then return 2; fi
            return 0;
        fi
        ((n++))
    done
}

# https://stackoverflow.com/a/7385197
function hash_hmac {
  digest="$1"
  data="$2"
  key="$3"
  shift 3
  # Don't print (stdin)= ...
  echo -n "$data" | openssl dgst "-$digest" -hmac "$key" | awk '{print $2}'
}