// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package etcdserver

import (
	"time"

	"github.com/coreos/etcd/etcdserver/membership"
	"github.com/coreos/etcd/pkg/types"
	"github.com/coreos/etcd/rafthttp"
)

// isConnectedToQuorumSince checks whether the local member is connected to the
// quorum of the cluster since the given time.
func isConnectedToQuorumSince(transport rafthttp.Transporter, since time.Time, self types.ID, members []*membership.Member) bool {
	var connectedNum int
	for _, m := range members {
		if m.ID == self || isConnectedSince(transport, since, m.ID) {
			connectedNum++
		}
	}
	return connectedNum >= (len(members)+1)/2
}

// isConnectedSince checks whether the local member is connected to the
// remote member since the given time.
func isConnectedSince(transport rafthttp.Transporter, since time.Time, remote types.ID) bool {
	t := transport.ActiveSince(remote)
	return !t.IsZero() && t.Before(since)
}
