#!/bin/bash
_temp="./download/dialog.$$"
_error="./.error.out"

# load network and chain info
network=`cat .network`
chain=$(sudo -bitcoin ${network}-cli -datadir=/home/bitcoin/.${network} getblockchaininfo | jq -r '.chain')

echo ""
echo "*** Precheck ***"

# check if chain is in sync
chainInSync=$(lncli --chain=${network} getinfo | grep '"synced_to_chain": true' -c)
if [ ${chainInSync} -eq 0 ]; then
  echo "!!!!!!!!!!!!!!!!!!!"
  echo "FAIL - 'lncli getinfo' shows 'synced_to_chain': false"
  echo "Wait until chain is sync with LND and try again."
  echo "!!!!!!!!!!!!!!!!!!!"
  echo ""
  exit 1
fi


# check number of connected peers
echo "check for open channels"
openChannels=$(sudo -u bitcoin /usr/local/bin/lncli --chain=${network} listchannels 2>/dev/null | grep chan_id -c)
if [ ${openChannels} -eq 0 ]; then
  echo ""
  echo "!!!!!!!!!!!!!!!!!!!"
  echo "FAIL - You have NO ESTABLISHED CHANNELS .. open a channel first."
  echo "!!!!!!!!!!!!!!!!!!!"
  echo ""
  exit 1
fi

paymentRequestStart="???"
if [ "${network}" = "bitcoin" ]; then
  if [ "${chain}" = "main" ]; then
    paymentRequestStart="lnbc"
  else
    paymentRequestStart="lntb"
  fi
elif [ "${network}" = "litecoin" ]; then
    paymentRequestStart="lnltc"
fi

testSite="???"
if [ "${network}" = "bitcoin" ]; then
  if [ "${chain}" = "main" ]; then
    testSite="https://satoshis.place"
  else
    testSite="https://testnet.satoshis.place"
  fi
elif [ "${network}" = "litecoin" ]; then
    testSite="https://millionlitecoinhomepage.net"
fi

# let user enter the invoice
l1="Copy the LightningInvoice/PaymentRequest into here:"
l2="Its a long string starting with '${paymentRequestStart}'"
l3="To try it out go to: ${testSite}"
dialog --title "Pay thru Lightning Network" \
--inputbox "$l1\n$l2\n$l3" 10 70 2>$_temp
invoice=$(cat $_temp | xargs)
shred $_temp
if [ ${#invoice} -eq 0 ]; then
  echo "FAIL - not a valid input (${invoice})"
  exit 1
fi

# TODO: maybe try/show the decoded info first by using https://api.lightning.community/#decodepayreq

# build command
command="lncli --chain=${network} sendpayment --pay_req=${invoice}"

# info output
clear
echo "******************************"
echo "Pay Invoice / Payment Request"
echo "******************************"
echo ""
echo "COMMAND LINE: "
echo $command
echo ""
echo "RESULT (may wait in case of timeout):"

# execute command
result=$($command 2>$_error)
error=`cat ${_error}`

#echo "result(${result})"
#echo "error(${error})"

if [ ${#error} -gt 0 ]; then
  echo "!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"
  echo "FAIL"
  echo "!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"
  echo "${error}"
else
  echo "${result}"
  echo "******************************"
  echo "WIN"
  echo "******************************"
  echo "It worked :) - check out the service you were paying."
fi
echo ""