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)
64 // blockHeader convert a node to the header struct
65 func (node *BlockNode) BlockHeader() *types.BlockHeader {
66 previousBlockHash := bc.Hash{}
67 if node.Parent != nil {
68 previousBlockHash = node.Parent.Hash
70 return &types.BlockHeader{
71 Version: node.Version,
73 PreviousBlockHash: previousBlockHash,
74 Timestamp: node.Timestamp,
77 BlockCommitment: types.BlockCommitment{
78 TransactionsMerkleRoot: node.TransactionsMerkleRoot,
79 TransactionStatusHash: node.TransactionStatusHash,
84 func (node *BlockNode) CalcPastMedianTime() uint64 {
85 timestamps := []uint64{}
87 for i := 0; i < consensus.MedianTimeBlocks && iterNode != nil; i++ {
88 timestamps = append(timestamps, iterNode.Timestamp)
89 iterNode = iterNode.Parent
92 sort.Sort(common.TimeSorter(timestamps))
93 return timestamps[len(timestamps)/2]
96 // CalcNextBits calculate the bits for next block
97 func (node *BlockNode) CalcNextBits() uint64 {
98 if node.Height%consensus.BlocksPerRetarget != 0 || node.Height == 0 {
102 compareNode := node.Parent
103 for compareNode.Height%consensus.BlocksPerRetarget != 0 {
104 compareNode = compareNode.Parent
106 return difficulty.CalcNextRequiredDifficulty(node.BlockHeader(), compareNode.BlockHeader())
109 // CalcNextSeed calculate the seed for next block
110 func (node *BlockNode) CalcNextSeed() *bc.Hash {
111 if node.Height == 0 {
112 return consensus.InitialSeed
114 if node.Height%consensus.SeedPerRetarget == 0 {
120 // BlockIndex is the struct for help chain trace block chain as tree
121 type BlockIndex struct {
124 index map[bc.Hash]*BlockNode
125 mainChain []*BlockNode
128 // NewBlockIndex will create a empty BlockIndex
129 func NewBlockIndex() *BlockIndex {
131 index: make(map[bc.Hash]*BlockNode),
132 mainChain: make([]*BlockNode, 0, approxNodesPerDay),
136 // AddNode will add node to the index map
137 func (bi *BlockIndex) AddNode(node *BlockNode) {
139 bi.index[node.Hash] = node
143 // GetNode will search node from the index map
144 func (bi *BlockIndex) GetNode(hash *bc.Hash) *BlockNode {
147 return bi.index[*hash]
150 func (bi *BlockIndex) BestNode() *BlockNode {
153 return bi.mainChain[len(bi.mainChain)-1]
156 // BlockExist check does the block existed in blockIndex
157 func (bi *BlockIndex) BlockExist(hash *bc.Hash) bool {
159 _, ok := bi.index[*hash]
164 // TODO: THIS FUNCTION MIGHT BE DELETED
165 func (bi *BlockIndex) InMainchain(hash bc.Hash) bool {
169 node, ok := bi.index[hash]
173 return bi.nodeByHeight(node.Height) == node
176 func (bi *BlockIndex) nodeByHeight(height uint64) *BlockNode {
177 if height >= uint64(len(bi.mainChain)) {
180 return bi.mainChain[height]
183 // NodeByHeight returns the block node at the specified height.
184 func (bi *BlockIndex) NodeByHeight(height uint64) *BlockNode {
187 return bi.nodeByHeight(height)
190 // SetMainChain will set the the mainChain array
191 func (bi *BlockIndex) SetMainChain(node *BlockNode) {
195 needed := node.Height + 1
196 if uint64(cap(bi.mainChain)) < needed {
197 nodes := make([]*BlockNode, needed, needed+approxNodesPerDay)
198 copy(nodes, bi.mainChain)
201 i := uint64(len(bi.mainChain))
202 bi.mainChain = bi.mainChain[0:needed]
203 for ; i < needed; i++ {
204 bi.mainChain[i] = nil
208 for node != nil && bi.mainChain[node.Height] != node {
209 bi.mainChain[node.Height] = node