#!/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

	gvm_export_path
	. "$GVM_ROOT/environments/$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"
}