whichydb

#!/usr/bin/env bash

me=$( basename $0 )

[[ "$1" ]] || {
	cat << EOT

Usage:  $me [ get | set_test | set_production ]

Get or set the current heroku yamz DATABASE_URL for use
with the "sea.py" yamz client.

EOT
	exit 1
}

function whichydb {
	envvar="$1"
	[[ "$envvar" ]] || {
		echo "whichydb: empty db setting argument"
		exit 1
	}
	n_v=$( sed -n 's/^\([^=]*\)=\(.*\)$/n="\1" v="\2"/p' \
		<<< "$envvar" )
	[[ "$n_v" ]] || {
		echo "DATABASE_URL ($envvar) malformed"
		exit 1
	}
	eval "$n_v"
	echo "$v"
	#echo n_v is $n_v
	#echo n is $n, v is $v
}

function getydbfor {		# print setting for instance named by arg
	heroku config -a "$1" | sed -n 's/^DATABASE_URL: *//p'
}

function setydbfor {
	d="$1"
	db=$( getydbfor $d )
	echo "($d): copy and paste next line into your shell"
	echo "  export DATABASE_URL=\"$db\""
}

[[ "$1" == "get" ]] && {
	curdb="$DATABASE_URL"			# ok, but is it env var?
	envdb=$( env | grep '^DATABASE_URL=' )	# both should be non-empty
	[[ "$curdb" && "$envdb" ]] || {
		echo "Env var DATABASE_URL not set"
		exit
	}
	settings=( tyamz yamz )
	for d in ${settings[*]}			# search for match
	do
		wouldbe=$( getydbfor $d )
		[[ "$curdb" == "$wouldbe" ]] && {
			echo $d
			exit
		}
	done
	echo "Setting not in: ( ${settings[*]} )"
	exit 1
}

[[ "$1" == "set_test" ]] && {
	echo "set_test $( setydbfor tyamz )"
	exit
}

[[ "$1" == "set_production" ]] && {
	echo "set_production $( setydbfor yamz )"
	exit
}

echo "Unknown command: $1"
exit