// Copyright 2020 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package build

import (
	"encoding/json"
	"errors"
)

// ErrArgNotSet represents an arg not having been set in the build.
var ErrArgNotSet = errors.New("arg not set")

// Args represents the GN arguments set in the build.
type Args map[string]json.RawMessage

// Get returns the value of a GN arg set in the build. If unset, ErrArgNotSet
// will be returned.
func (args Args) Get(name string, v any) error {
	msg, ok := args[name]
	if !ok {
		return ErrArgNotSet
	}
	return json.Unmarshal(msg, v)
}