// Copyright (C) 2020 Storj Labs, Inc.
// See LICENSE for copying information.

// Package admin implements administrative endpoints for satellite.
package admin

import (
	"context"
	"net"
	"net/http"

	"github.com/gorilla/mux"
	"go.uber.org/zap"
	"golang.org/x/sync/errgroup"
)

// Config defines configuration for debug server.
type Config struct {
	Address string `help:"admin peer http listening address" releaseDefault:"" devDefault:""`
}

// Server provides endpoints for debugging.
type Server struct {
	log *zap.Logger

	listener net.Listener
	server   http.Server
	mux      mux.Router
}

// NewServer returns a new debug.Server.
func NewServer(log *zap.Logger, listener net.Listener, config Config) *Server {
	server := &Server{log: log}

	server.listener = listener
	server.server.Handler = &server.mux

	return server
}

// Run starts the debug endpoint.
func (server *Server) Run(ctx context.Context) error {
	if server.listener == nil {
		return nil
	}

	ctx, cancel := context.WithCancel(ctx)
	var group errgroup.Group
	group.Go(func() error {
		<-ctx.Done()
		return Error.Wrap(server.server.Shutdown(context.Background()))
	})
	group.Go(func() error {
		defer cancel()
		return Error.Wrap(server.server.Serve(server.listener))
	})
	return group.Wait()
}

// Close closes server and underlying listener.
func (server *Server) Close() error {
	return Error.Wrap(server.server.Close())
}