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1// OCRProtocol 链下报告共识
2type OCRProtocol struct {
3    nodeID      peer.ID
4    peers       []peer.ID
5    threshold   int
6    currentRound uint64
7    observations map[uint64][]Observation
8}
9 
10// Observation 节点观测值
11type Observation struct {
12    NodeID    peer.ID
13    Value     *big.Int
14    Timestamp time.Time
15    Signature []byte
16}
17 
18// RunConsensusRound 执行共识轮次
19func (o *OCRProtocol) RunConsensusRound(
20    ctx context.Context,
21) (*Report, error) {
22    round := atomic.AddUint64(&o.currentRound, 1)
23    
24    // 1. 收集观测值
25    observation, err := o.collectObservation(ctx)
26    if err != nil {
27        return nil, err
28    }
29    
30    // 2. 广播观测值给所有节点
31    signedObs := o.signObservation(observation)
32    o.broadcast(ctx, &ObservationMessage{
33        Round:       round,
34        Observation: signedObs,
35    })
36    
37    // 3. 等待收集足够的观测值
38    observations, err := o.waitForObservations(ctx, round, o.threshold)
39    if err != nil {
40        return nil, fmt.Errorf("collect observations: %w", err)
41    }
42    
43    // 4. 如果是 Leader，生成报告
44    if o.isLeader(round) {
45        report := o.generateReport(round, observations)
46        
47        // 5. 收集签名
48        signatures, err := o.collectSignatures(ctx, report)
49        if err != nil {
50            return nil, err
51        }
52        
53        report.Signatures = signatures
54        return report, nil
55    }
56    
57    // Follower: 等待 Leader 的报告并签名
58    return o.waitAndSignReport(ctx, round)
59}
60 
61// generateReport 生成共识报告
62func (o *OCRProtocol) generateReport(
63    round uint64,
64    observations []Observation,
65) *Report {
66    // 提取所有值并排序
67    values := make([]*big.Int, len(observations))
68    for i, obs := range observations {
69        values[i] = obs.Value
70    }
71    sort.Slice(values, func(i, j int) bool {
72        return values[i].Cmp(values[j]) < 0
73    })
74    
75    // 取中位数
76    median := values[len(values)/2]
77    
78    return &Report{
79        Round:        round,
80        MedianValue:  median,
81        Observations: observations,
82        Timestamp:    time.Now(),
83    }
84}