#!/bin/bash

_SQLITE=$( which sqlite3 2>&1 )
if [ $? -ne 0 ]; then
    echo "sqlite3 is missing" >&2
    return 1
fi

echo "test" | openssl enc -e -aes-256-cbc -pbkdf2 -k test 2>/dev/null > /dev/null
if [ $? -ne 0 ]; then
    echo "openssl does not exists nor support pbkdf2" >&2
    return 1
fi

_AUTH_DB=$RBASH_HOME/keystore.db
_AUTH_SECRET=
_KSTORE_DEF_PROP=${_KSTORE_DEF_PROP:-val}

if [ -f "$RBASH_HOME/keystore.secret" ]; then
	_AUTH_SECRET=$( cat "$RBASH_HOME/keystore.secret" )
fi

function kstore {
	case $1 in
		add) shift; kstore-add "$@" ;;
		del) shift; kstore-del "$@" ;;
		get) shift; kstore-get "$@" ;;
		list) shift; kstore-list "$@" ;;
		query) shift; kstore-query "$@" ;;
		update) shift; kstore-update "$@" ;;
		search) shift; kstore-search $@ ;;
		secret) shift; kstore-secret $@ ;;
		*)
			__func_head "add key value|file|- [prop, default: $_KSTORE_DEF_PROP]"
			__func_help "update key value|file|- [prop, default: $_KSTORE_DEF_PROP]"
			__func_help "get key [prop, default: $_KSTORE_DEF_PROP]"
			__func_help "list"
			__func_help "del key"
			__func_help "search key"
			__func_help "query SQL"
			return 1
			;;
	esac
	return $?
}

function kstore-secret {
	case "$1" in
		clear) shift; kstore-secret-clear "$@" ;;
		config) shift; kstore-secret-config "$@" ;;
		*)
			__func_head "clear"
			__func_help "config"
			;;
	esac
}

function kstore-init {
	cat <<___SQL___ | $_SQLITE "$_AUTH_DB"
CREATE TABLE IF NOT EXISTS store ( 
	key TEXT UNIQUE NOT NULL
	, prop TEXT NOT NULL
	, data TEXT
	, PRIMARY KEY( key ASC, prop ASC )
);
___SQL___
	kstore secret config
}

function kstore-quote {
	echo -n "$1" | sed -e "s/'/''/g"
}

function kstore-enc {
	if [ -z "$_AUTH_SECRET" ]; then
		echo "Secret key is not set yet" >&2
		return 1
	fi

	if [ "$1" == "-" ]; then
		openssl enc -e -aes-256-cbc -pbkdf2 -k "$_AUTH_SECRET" -a -A
	elif [ -f "$1" ]; then
		openssl enc -e -aes-256-cbc -pbkdf2 -k "$_AUTH_SECRET" -a -A -in "$1"
	else
		echo -n "$1" | openssl enc -e -aes-256-cbc -pbkdf2 -k "$_AUTH_SECRET" -a -A
	fi
}

function kstore-dec {
	if [ -z "$_AUTH_SECRET" ]; then
		echo "Secret key is not set yet" >&2
		return 1
	fi

	openssl enc -d -aes-256-cbc -pbkdf2 -k "$_AUTH_SECRET" -a -A
}

function kstore-secret-macos {
	local _A
	case $1 in
		get)
			_A=`security find-generic-password -a default -gs rbash-kstore 2>&1 | grep ^password | cut -c 11-`
			if [ $? -ne 0 ]; then
				return 1
			fi
			_AUTH_SECRET="${_A:1:-1}"
			;;
		set)
			security add-generic-password -a default -s rbash-kstore -w "$_AUTH_SECRET"
			;;
		*)
			echo "Unknown action: $1" >&2
			return 1
			;;
	esac
}

function kstore-secret-windows {
	# Not impelemented yet
	if [ "$1" == "get" ]; then
		return 1
	fi
	return 1
}

function kstore-secret-config {
	local _CONFIRM
	if [ -z "$_AUTH_SECRET" ]; then

		kstore-secret-windows get || kstore-secret-macos get
		if [ -n "$_AUTH_SECRET" ]; then
			return 0
		fi

		read -sp "Enter passphrase: " _AUTH_SECRET
		echo
		if [ -z "$_AUTH_SECRET" ]; then
			echo "Passphrase cannot be empty" >&2
			return 1
		fi

		read -p "Save this password to OS's keystore? (y/n): " _CONFIRM
		if [ "$_CONFIRM" != "y" ]; then
			return 0
		fi

		case $OSTYPE in
			darwin*) kstore-secret-macos "set" ;;
		esac
	fi
}

function kstore-secret-clear {
	_AUTH_SECRET=
	case $OSTYPE in
		darwin*)
			security delete-generic-password -a default -s rbash-kstore 2>&1 > /dev/null
		;;
	esac
}

function kstore-update {
	kstore-init || return 1
	local _key _val _prop
	_key=`kstore-quote "$1"`
	_val=`kstore-enc "$2"`
	_val=`kstore-quote "$_val"`
	_prop=`kstore-quote "${3:-$_KSTORE_DEF_PROP}"`
	_cond="key = '$_key' AND prop = '$_prop'"
	$_SQLITE "$_AUTH_DB" "UPDATE store SET data = '$_val' WHERE $_cond;"
}

function kstore-add {
	kstore-init || return 1
	local _key _val _prop
	_key=`kstore-quote "$1"`
	_val=`kstore-enc "$2"`
	_val=`kstore-quote "$_val"`
	_prop=`kstore-quote "${3:-$_KSTORE_DEF_PROP}"`
    sqlite3 "$_AUTH_DB" \
		"INSERT INTO store ( key, prop, data )
			VALUES( '$_key', '$_prop', '$_val' );"
}

function kstore-get {
	kstore-init || return 1
	local _key _prop _cond
	_key=`kstore-quote "$1"`
	_prop=`kstore-quote "${2:-$_KSTORE_DEF_PROP}"`
	_cond="key = '$_key' AND prop = '$_prop'"

    sqlite3 "$_AUTH_DB" "SELECT 1111 FROM store WHERE $_cond;" | grep -q 1111
	if [ $? -eq 0 ]; then
		$_SQLITE -list "$_AUTH_DB" "SELECT ( data ) FROM store WHERE $_cond;" | kstore-dec
	else
		echo "\"$1\" not found" >&2
	fi
}

function kstore-del {
	kstore-init || return 1

	local _CONFIRM _key _prop _cond
	_key=`kstore-quote "$1"`
	_prop=`kstore-quote "${2:-$_KSTORE_DEF_PROP}"`
	_cond="key = '$_key' AND prop = '$_prop'"

    sqlite3 "$_AUTH_DB" "SELECT 1111 FROM store WHERE $_cond;" | grep -q 1111
	if [ $? -eq 0 ]; then
		sqlite3 "$_AUTH_DB" "SELECT * FROM store WHERE $_cond;"
		echo
		read -p "Delete this entry (yes/no)? " _CONFIRM
		if [ "$_CONFIRM" == "yes" ]; then
			sqlite3 "$_AUTH_DB" "DELETE FROM store WHERE $_cond;"
			if [ $? -eq 0 ]; then
				echo "deleted"
			fi
		else
			echo "action canceled"
		fi
	else
		echo "\"$1\" not found" >&2
	fi
}

function kstore-search {
	echo "Not implemented yet"
}

function kstore-list {
	$_SQLITE -header -column "$_AUTH_DB" "SELECT key, prop, length( data ) FROM store;"
}

function kstore-query {
	sqlite3 "$_AUTH_DB" "$@"
}