9 "github.com/vapor/common"
10 "github.com/vapor/consensus"
11 "github.com/vapor/consensus/difficulty"
12 "github.com/vapor/protocol/bc"
13 "github.com/vapor/protocol/bc/types"
16 // approxNodesPerDay is an approximation of the number of new blocks there are
17 // in a day on average.
18 const approxNodesPerDay = 24 * 24
20 // BlockNode represents a block within the block chain and is primarily used to
21 // aid in selecting the best chain to be the main chain.
22 type BlockNode struct {
23 Parent *BlockNode // parent is the parent block for this node.
24 Hash bc.Hash // hash of the block.
25 Seed *bc.Hash // seed hash of the block
26 WorkSum *big.Int // total amount of work in the chain up to
33 TransactionsMerkleRoot bc.Hash
34 TransactionStatusHash bc.Hash
37 func NewBlockNode(bh *types.BlockHeader, parent *BlockNode) (*BlockNode, error) {
38 if bh.Height != 0 && parent == nil {
39 return nil, errors.New("parent node can not be nil")
45 //WorkSum: difficulty.CalcWork(bh.Bits),
48 Timestamp: bh.Timestamp,
51 TransactionsMerkleRoot: bh.TransactionsMerkleRoot,
52 TransactionStatusHash: bh.TransactionStatusHash,
56 node.Seed = consensus.InitialSeed
58 node.Seed = parent.CalcNextSeed()
59 node.WorkSum = node.WorkSum.Add(parent.WorkSum, node.WorkSum)
65 // blockHeader convert a node to the header struct
66 func (node *BlockNode) BlockHeader() *types.BlockHeader {
67 previousBlockHash := bc.Hash{}
68 if node.Parent != nil {
69 previousBlockHash = node.Parent.Hash
71 return &types.BlockHeader{
72 Version: node.Version,
74 PreviousBlockHash: previousBlockHash,
75 Timestamp: node.Timestamp,
76 BlockCommitment: types.BlockCommitment{
77 TransactionsMerkleRoot: node.TransactionsMerkleRoot,
78 TransactionStatusHash: node.TransactionStatusHash,
83 func (node *BlockNode) CalcPastMedianTime() uint64 {
84 timestamps := []uint64{}
86 for i := 0; i < consensus.MedianTimeBlocks && iterNode != nil; i++ {
87 timestamps = append(timestamps, iterNode.Timestamp)
88 iterNode = iterNode.Parent
91 sort.Sort(common.TimeSorter(timestamps))
92 return timestamps[len(timestamps)/2]
95 // CalcNextBits calculate the bits for next block
96 func (node *BlockNode) CalcNextBits() uint64 {
97 if node.Height%consensus.BlocksPerRetarget != 0 || node.Height == 0 {
101 compareNode := node.Parent
102 for compareNode.Height%consensus.BlocksPerRetarget != 0 {
103 compareNode = compareNode.Parent
105 return difficulty.CalcNextRequiredDifficulty(node.BlockHeader(), compareNode.BlockHeader())
108 // CalcNextSeed calculate the seed for next block
109 func (node *BlockNode) CalcNextSeed() *bc.Hash {
110 if node.Height == 0 {
111 return consensus.InitialSeed
113 if node.Height%consensus.SeedPerRetarget == 0 {
119 // BlockIndex is the struct for help chain trace block chain as tree
120 type BlockIndex struct {
123 index map[bc.Hash]*BlockNode
124 mainChain []*BlockNode
127 // NewBlockIndex will create a empty BlockIndex
128 func NewBlockIndex() *BlockIndex {
130 index: make(map[bc.Hash]*BlockNode),
131 mainChain: make([]*BlockNode, 0, approxNodesPerDay),
135 // AddNode will add node to the index map
136 func (bi *BlockIndex) AddNode(node *BlockNode) {
138 bi.index[node.Hash] = node
142 // GetNode will search node from the index map
143 func (bi *BlockIndex) GetNode(hash *bc.Hash) *BlockNode {
146 return bi.index[*hash]
149 func (bi *BlockIndex) BestNode() *BlockNode {
152 return bi.mainChain[len(bi.mainChain)-1]
155 // BlockExist check does the block existed in blockIndex
156 func (bi *BlockIndex) BlockExist(hash *bc.Hash) bool {
158 _, ok := bi.index[*hash]
163 // TODO: THIS FUNCTION MIGHT BE DELETED
164 func (bi *BlockIndex) InMainchain(hash bc.Hash) bool {
168 node, ok := bi.index[hash]
172 return bi.nodeByHeight(node.Height) == node
175 func (bi *BlockIndex) nodeByHeight(height uint64) *BlockNode {
176 if height >= uint64(len(bi.mainChain)) {
179 return bi.mainChain[height]
182 // NodeByHeight returns the block node at the specified height.
183 func (bi *BlockIndex) NodeByHeight(height uint64) *BlockNode {
186 return bi.nodeByHeight(height)
189 // SetMainChain will set the the mainChain array
190 func (bi *BlockIndex) SetMainChain(node *BlockNode) {
194 needed := node.Height + 1
195 if uint64(cap(bi.mainChain)) < needed {
196 nodes := make([]*BlockNode, needed, needed+approxNodesPerDay)
197 copy(nodes, bi.mainChain)
200 i := uint64(len(bi.mainChain))
201 bi.mainChain = bi.mainChain[0:needed]
202 for ; i < needed; i++ {
203 bi.mainChain[i] = nil
207 for node != nil && bi.mainChain[node.Height] != node {
208 bi.mainChain[node.Height] = node