lotus/chain/types/tipset.go
2019-08-29 19:59:54 -07:00

123 lines
2.3 KiB
Go

package types
import (
"bytes"
"encoding/json"
"fmt"
"github.com/ipfs/go-cid"
logging "github.com/ipfs/go-log"
)
var log = logging.Logger("types")
type TipSet struct {
cids []cid.Cid
blks []*BlockHeader
height uint64
}
// why didnt i just export the fields? Because the struct has methods with the
// same names already
type expTipSet struct {
Cids []cid.Cid
Blocks []*BlockHeader
Height uint64
}
func (ts *TipSet) MarshalJSON() ([]byte, error) {
return json.Marshal(expTipSet{
Cids: ts.cids,
Blocks: ts.blks,
Height: ts.height,
})
}
func (ts *TipSet) UnmarshalJSON(b []byte) error {
var ets expTipSet
if err := json.Unmarshal(b, &ets); err != nil {
return err
}
ts.cids = ets.Cids
ts.blks = ets.Blocks
ts.height = ets.Height
return nil
}
func NewTipSet(blks []*BlockHeader) (*TipSet, error) {
var ts TipSet
ts.cids = []cid.Cid{blks[0].Cid()}
ts.blks = blks
for _, b := range blks[1:] {
if b.Height != blks[0].Height {
return nil, fmt.Errorf("cannot create tipset with mismatching heights")
}
ts.cids = append(ts.cids, b.Cid())
}
ts.height = blks[0].Height
return &ts, nil
}
func (ts *TipSet) Cids() []cid.Cid {
return ts.cids
}
func (ts *TipSet) Height() uint64 {
return ts.height
}
func (ts *TipSet) Weight() BigInt {
// TODO: implement correctly
log.Warn("Called TipSet.Weight: TODO: correct implementation")
return BigAdd(ts.blks[0].ParentWeight, NewInt(1))
}
func (ts *TipSet) Parents() []cid.Cid {
return ts.blks[0].Parents
}
func (ts *TipSet) Blocks() []*BlockHeader {
return ts.blks
}
func (ts *TipSet) Equals(ots *TipSet) bool {
if len(ts.blks) != len(ots.blks) {
return false
}
for i, b := range ts.blks {
if b.Cid() != ots.blks[i].Cid() {
return false
}
}
return true
}
func (ts *TipSet) MinTicket() *Ticket {
if len(ts.Blocks()) == 0 {
panic("tipset has no blocks!")
}
var minTicket *Ticket
for _, b := range ts.Blocks() {
lastTicket := b.Tickets[len(b.Tickets)-1]
if minTicket == nil || bytes.Compare(lastTicket.VDFResult, minTicket.VDFResult) < 0 {
minTicket = lastTicket
}
}
return minTicket
}
func (ts *TipSet) MinTimestamp() uint64 {
minTs := ts.Blocks()[0].Timestamp
for _, bh := range ts.Blocks()[1:] {
if bh.Timestamp < minTs {
minTs = bh.Timestamp
}
}
return minTs
}