// Copyright (c) 2021 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

package metrics

import "context"

type contextTag string

const contextTagsKey = contextTag("metrics.Tags")

func TagContext(ctx context.Context, ctxTags ...Tag) context.Context {
	tags, ok := ctx.Value(contextTagsKey).([]Tag)
	if !ok {
		tags = []Tag{}
	}
	tags = append(tags, ctxTags...)
	return context.WithValue(ctx, contextTagsKey, tags)
}

func GetContextTags(ctx context.Context) []Tag {
	tags, ok := ctx.Value(contextTagsKey).([]Tag)
	if !ok {
		tags = []Tag{}
	}
	return tags
}
