// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

// This file contains some shares testing functionality, common to  multiple
// different files and modules being tested.

package diff

import (
	"crypto/rand"

	"github.com/ethereum/go-ethereum/p2p"
	"github.com/ethereum/go-ethereum/p2p/enode"
)

// testPeer is a simulated peer to allow testing direct network calls.
type testPeer struct {
	*Peer

	net p2p.MsgReadWriter // Network layer reader/writer to simulate remote messaging
	app *p2p.MsgPipeRW    // Application layer reader/writer to simulate the local side
}

// newTestPeer creates a new peer registered at the given data backend.
func newTestPeer(name string, version uint, backend Backend) (*testPeer, <-chan error) {
	// Create a message pipe to communicate through
	app, net := p2p.MsgPipe()

	// Start the peer on a new thread
	var id enode.ID
	rand.Read(id[:])

	peer := NewPeer(version, p2p.NewPeer(id, name, nil), net)
	errc := make(chan error, 1)
	go func() {
		errc <- backend.RunPeer(peer, func(peer *Peer) error {
			return Handle(backend, peer)
		})
	}()
	return &testPeer{app: app, net: net, Peer: peer}, errc
}

// close terminates the local side of the peer, notifying the remote protocol
// manager of termination.
func (p *testPeer) close() {
	p.Peer.Close()
	p.app.Close()
}