#!/usr/bin/env bash
function gvm_use() {
	[[ "$1" != "" ]] ||
		display_error "Please specifiy the version" || return 1
	local VERSION=$1
	fuzzy_match=`$LS_PATH $GVM_ROOT/gos | $SORT_PATH | $GREP_PATH "$1" | $HEAD_PATH -n 1 | $GREP_PATH "$1"`
	if [[ "$?" != "0" ]]; then
		GO_CACHE_PATH=$GVM_ROOT/archive/go
		version=`hg tags -R $GO_CACHE_PATH | awk '{print $1}' | $SORT_PATH | $GREP_PATH "$VERSION" | $HEAD_PATH -n 1 | $GREP_PATH "$VERSION"`
		if [[ "x$version" == "x" ]]; then
			display_error "Version not found locally. Try 'gvm install $1'" || return 1
		else
			display_warning "$version is not installed. Install it by running 'gvm install $version'" || return 1
		fi
	fi

	export PATH=$GVM_PATH_BACKUP
	. $GVM_ROOT/environments/$fuzzy_match &> /dev/null || display_error "Couldn't source environment" || return 1
	if [[ "$2" == "--default" ]]; then
		cp $GVM_ROOT/environments/$fuzzy_match $GVM_ROOT/environments/default || display_error "Couldn't make $fuzzy_match default"
	fi

	display_message "Now using version $fuzzy_match"
}