#!/bin/bash
# This file describe the structure of the ArchingKaos messages in their basis.
#
# As previously thought, we exchange one IPFS hash through whatever means we can.
# 
# GPG is mentioned as a signing algorithm for encryption, decryption and signing.
# Let's say we have a file named as `example`
#
# We can extend this with calling the encoder and further send the transaction
#

#FINGERPRINT="CHANGE THIS TO YOUR DEFAULT FINGERPRINT"
# We acquire the GPG fingerprint by email address
# The following example finds kaos@kaos.kaos' GPG fingerprint like this
# FINGERPRINT="$(gpg2 --list-keys | grep kaos@kaos.kaos -1 | head -n1 | awk '{print $1}')"

# Below, the usage information
PROGRAM="zblock_manipulator"

usage(){
	echo "Usage:"	
	echo "$PROGRAM -b block_file | -h block_hash | dunno"
	echo "Creates and publishes a ZBLOCK based on a block and a previous"
	echo "zblock."
	echo ""
	echo "Either -b or -h is needed. If both, -h is used."
	echo ""
	echo "-b block_file		Points to a block file that we want to fix."
	echo "-h block_hash		If we don't have the block as a file, we can"
	echo "				use it's hash to retrieve it and edit it."
	echo "-p previous_hash		We refering to a previous hash for a ZBLOCK."
	echo ""
	echo "#TODO:"
	echo "-t timestamp		Unix UTC timestamp in seconds."
	echo "-a \"module/action\"	Change the action tag. Format: object/verb."
	echo "				In sense, \"Add news -> news/add\"."
	echo "-d data			In case you want to change the data, you 'll"
	echo "				be changing potentially the key of the block"
	echo "				and the data signature, otherwise your block"
	echo "				will be unverified."
	echo ""
}

main(){
 
	logthis "We are doing" $BLOCK_TO_ADD "with content" $PREVIOUS
	# We add it to IPFS
	MESSAGE_HASH=$(ipfs add -q $MESSAGE)

	# We create a detached and armor signature of it
	MESSAGE_SIGN_FILE=$MESSAGE".asc"
	gpg2 --detach-sign --sign-with $FINGERPRINT --armor --output $MESSAGE_SIGN_FILE $MESSAGE

	# We add the signature to IPFS
	MESSAGE_SIGNATURE=$(ipfs add -q $MESSAGE_SIGN_FILE)

	# We will be using our public key also to put it in the block later
	KEY="gpg.pub"
	gpg2 --armour --output $KEY --export $FINGERPRINT
	GPG_PUB_KEY=$(ipfs add -q $KEY)

	# Acquire last block of information, to chain this one with previous posted
	PREVIOUS=$(ipfs files stat /zlatest | head -n 1)

	# We create a block of json like this:
	cat > block <<EOF
{
    "timestamp":"$(date -u +%s)",
    "action":"$ACTION",
    "data":"$MESSAGE_HASH",
    "detach":"$MESSAGE_SIGNATURE",
    "gpg":"$GPG_PUB_KEY",
    "previous":"$PREVIOUS"
}
EOF
}
makeZBlock(){
	BLOCK="block"
	BLOCK_SIG=$BLOCK".asc"
	# We have a block now, so we sign it
	gpg2 --detach-sign --sign-with $FINGERPRINT --armor --output $BLOCK_SIG $BLOCK

	# We now add the signature to IPFS
	BLOCK_SIGNATURE=$(ipfs add -q $BLOCK_SIG)

	# We also add the block!
	BLOCK=$(ipfs add -q $BLOCK)

	# So we now do the think almost again
	cat > zblock << EOF
{
    "block":"$BLOCK",
    "block_signature":"$BLOCK_SIGNATURE"
}
EOF
	ZBL="zblock"
	# and we add it on IPFS
	ZBLOCK=$(ipfs add -q $ZBL)
	echo $ZBLOCK
}

if [ ! -z $2 ];
then
	PWD="$(pwd)"

	# We ask which BLOCK is goind to be edited
	BLOCK_TO_ADD="$1"
	# We ask for a ZBLOCK or GENESIS to put in the BLOCK
	PREVIOUS="$2"

	ipfs cat "$BLOCK_TO_ADD"
	if [ "$?" == 0 ];
	then
		echo "Nice! We found the block"
		ipfs get "$BLOCK_TO_ADD"

		sed -i.bak -e 's/^.*previous.*$/\"previous\":\"'$PREVIOUS'\"/' $BLOCK_TO_ADD
		cat $BLOCK_TO_ADD | json_pp

		exit 2
	else
		echo "Too bad, it seems the block is not there"
		exit 1
	fi

	# cat $PWD/zblock | json_pp
	# Optional or extending with
	# python send_as_ak_tx $ZBLOCK
	# or for "offline" use
	echo $ZBLOCK > $ZLATEST
	ipfs name publish --key=zchain $ZBLOCK > /dev/null 2>&1
	ipfs files mkdir /zarchive > /dev/null 2>&1
	ipfs files cp /zlatest /zarchive/$(date -u +%s)-$(ipfs files stat /zlatest | head -n 1) > /dev/null 2>&1
	ipfs files rm /zlatest > /dev/null 2>&1
	ipfs files cp /ipfs/$ZBLOCK /zlatest > /dev/null 2>&1
else
	usage
	exit 0
fi