Fix proof of work for genesis block (#22)

* Fix proof of work for genesis block

* Add POW tests

* Update genesis.go

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Fix lint

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: galt-tr

genesis.go

@@ -147,19 +147,19 @@ var teraTestNetGenesisBlock = wire.MsgBlock{
 		PrevBlock:  chainhash.Hash{},         // 0000000000000000000000000000000000000000000000000000000000000000
 		MerkleRoot: testNetGenesisMerkleRoot, // 4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b
 		Timestamp:  time.Unix(1755606836, 0), // 2025-08-19T08:33:56 +0000 UTC
-		Bits:       0x1d00ffff,               // 486604799 [00000000ffff0000000000000000000000000000000000000000000000000000]
-		Nonce:      0x18aea41a,               // 414098458
+		Bits:       0x207fffff,               // Easy difficulty for test network
+		Nonce:      0x00000002,               // Nonce value that produces a block hash meeting the proof-of-work requirement for 0x207fffff difficulty
 	},
 	Transactions: []*wire.MsgTx{&genesisCoinbaseTx},
 }
 
 // teraTestNetGenesisHash is the hash of the first block in the blockchain for the
 // tera test network.
 var teraTestNetGenesisHash = chainhash.Hash([chainhash.HashSize]byte{ // Make go vet happy.
-	0x12, 0x32, 0x0e, 0x07, 0x48, 0xfd, 0x4c, 0x44,
-	0x1d, 0x2d, 0x97, 0xba, 0x98, 0x56, 0xcd, 0xdd,
-	0x27, 0x13, 0x42, 0xe1, 0xb2, 0xc5, 0x17, 0x30,
-	0x97, 0x64, 0x58, 0x89, 0x33, 0xe1, 0x27, 0x1a,
+	0x5c, 0xce, 0x10, 0x0b, 0x1e, 0x5e, 0xdf, 0x9a,
+	0x24, 0x22, 0x6f, 0x6a, 0x75, 0x50, 0x18, 0x2c,
+	0xd3, 0xe8, 0xb9, 0x58, 0x65, 0x98, 0xcc, 0xa2,
+	0xf9, 0x43, 0xa4, 0x09, 0x32, 0x4b, 0xa0, 0xef,
 })
 
 // stnGenesisHash is the hash of the first block in the blockchain for the

genesis_test.go

@@ -7,6 +7,7 @@ package chaincfg
 import (
 	"bytes"
 	"encoding/hex"
+	"math/big"
 	"testing"
 
 	"github.com/bsv-blockchain/go-bt/v2"
@@ -313,40 +314,57 @@ func TestTeraTestNetGenesisBlock(t *testing.T) {
 // teraTestNetGenesisBlockBytes are the wire-encoded bytes for the genesis block of
 // the tera test network as of protocol version 60002.
 var teraTestNetGenesisBlockBytes = []byte{
-	0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* |........| */
-	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* |........| */
-	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* |........| */
-	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* |........| */
-	0x00, 0x00, 0x00, 0x00, 0x3b, 0xa3, 0xed, 0xfd, /* |....;...| */
-	0x7a, 0x7b, 0x12, 0xb2, 0x7a, 0xc7, 0x2c, 0x3e, /* |z{..z.,>| */
-	0x67, 0x76, 0x8f, 0x61, 0x7f, 0xc8, 0x1b, 0xc3, /* |gv.a....| */
-	0x88, 0x8a, 0x51, 0x32, 0x3a, 0x9f, 0xb8, 0xaa, /* |..Q2:...| */
-	0x4b, 0x1e, 0x5e, 0x4a, 0x34, 0x6f, 0xa4, 0x68, /* |K.^J4o.h| */
-	0xff, 0xff, 0x00, 0x1d, 0x1a, 0xa4, 0xae, 0x18, /* |........| */
-	0x01, 0x01, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, /* |........| */
-	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* |........| */
-	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* |........| */
-	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* |........| */
-	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, /* |........| */
-	0xff, 0xff, 0x4d, 0x04, 0xff, 0xff, 0x00, 0x1d, /* |..M.....| */
-	0x01, 0x04, 0x45, 0x54, 0x68, 0x65, 0x20, 0x54, /* |..EThe T| */
-	0x69, 0x6d, 0x65, 0x73, 0x20, 0x30, 0x33, 0x2f, /* |imes 03/| */
-	0x4a, 0x61, 0x6e, 0x2f, 0x32, 0x30, 0x30, 0x39, /* |Jan/2009| */
-	0x20, 0x43, 0x68, 0x61, 0x6e, 0x63, 0x65, 0x6c, /* | Chancel| */
-	0x6c, 0x6f, 0x72, 0x20, 0x6f, 0x6e, 0x20, 0x62, /* |lor on b| */
-	0x72, 0x69, 0x6e, 0x6b, 0x20, 0x6f, 0x66, 0x20, /* |rink of | */
-	0x73, 0x65, 0x63, 0x6f, 0x6e, 0x64, 0x20, 0x62, /* |second b| */
-	0x61, 0x69, 0x6c, 0x6f, 0x75, 0x74, 0x20, 0x66, /* |ailout f| */
-	0x6f, 0x72, 0x20, 0x62, 0x61, 0x6e, 0x6b, 0x73, /* |or banks| */
-	0xff, 0xff, 0xff, 0xff, 0x01, 0x00, 0xf2, 0x05, /* |........| */
-	0x2a, 0x01, 0x00, 0x00, 0x00, 0x43, 0x41, 0x04, /* |*....CA.| */
-	0x67, 0x8a, 0xfd, 0xb0, 0xfe, 0x55, 0x48, 0x27, /* |g....UH'| */
-	0x19, 0x67, 0xf1, 0xa6, 0x71, 0x30, 0xb7, 0x10, /* |.g..q0..| */
-	0x5c, 0xd6, 0xa8, 0x28, 0xe0, 0x39, 0x09, 0xa6, /* |\..(.9..| */
-	0x79, 0x62, 0xe0, 0xea, 0x1f, 0x61, 0xde, 0xb6, /* |yb...a..| */
-	0x49, 0xf6, 0xbc, 0x3f, 0x4c, 0xef, 0x38, 0xc4, /* |I..?L.8.| */
-	0xf3, 0x55, 0x04, 0xe5, 0x1e, 0xc1, 0x12, 0xde, /* |.U......| */
-	0x5c, 0x38, 0x4d, 0xf7, 0xba, 0x0b, 0x8d, 0x57, /* |\8M....W| */
-	0x8a, 0x4c, 0x70, 0x2b, 0x6b, 0xf1, 0x1d, 0x5f, /* |.Lp+k.._| */
-	0xac, 0x00, 0x00, 0x00, 0x00, /* |.....| */
+	0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* |................| */
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* |................| */
+	0x00, 0x00, 0x00, 0x00, 0x3b, 0xa3, 0xed, 0xfd, 0x7a, 0x7b, 0x12, 0xb2, 0x7a, 0xc7, 0x2c, 0x3e, /* |....;...z{..z.,>| */
+	0x67, 0x76, 0x8f, 0x61, 0x7f, 0xc8, 0x1b, 0xc3, 0x88, 0x8a, 0x51, 0x32, 0x3a, 0x9f, 0xb8, 0xaa, /* |gv.a......Q2:...| */
+	0x4b, 0x1e, 0x5e, 0x4a, 0x34, 0x6f, 0xa4, 0x68, 0xff, 0xff, 0x7f, 0x20, 0x02, 0x00, 0x00, 0x00, /* |K.^J4o.h... ....| */
+	0x01, 0x01, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* |................| */
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* |................| */
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0x4d, 0x04, 0xff, 0xff, 0x00, 0x1d, /* |..........M.....| */
+	0x01, 0x04, 0x45, 0x54, 0x68, 0x65, 0x20, 0x54, 0x69, 0x6d, 0x65, 0x73, 0x20, 0x30, 0x33, 0x2f, /* |..EThe Times 03/| */
+	0x4a, 0x61, 0x6e, 0x2f, 0x32, 0x30, 0x30, 0x39, 0x20, 0x43, 0x68, 0x61, 0x6e, 0x63, 0x65, 0x6c, /* |Jan/2009 Chancel| */
+	0x6c, 0x6f, 0x72, 0x20, 0x6f, 0x6e, 0x20, 0x62, 0x72, 0x69, 0x6e, 0x6b, 0x20, 0x6f, 0x66, 0x20, /* |lor on brink of | */
+	0x73, 0x65, 0x63, 0x6f, 0x6e, 0x64, 0x20, 0x62, 0x61, 0x69, 0x6c, 0x6f, 0x75, 0x74, 0x20, 0x66, /* |second bailout f| */
+	0x6f, 0x72, 0x20, 0x62, 0x61, 0x6e, 0x6b, 0x73, 0xff, 0xff, 0xff, 0xff, 0x01, 0x00, 0xf2, 0x05, /* |or banks........| */
+	0x2a, 0x01, 0x00, 0x00, 0x00, 0x43, 0x41, 0x04, 0x67, 0x8a, 0xfd, 0xb0, 0xfe, 0x55, 0x48, 0x27, /* |*....CA.g....UH'| */
+	0x19, 0x67, 0xf1, 0xa6, 0x71, 0x30, 0xb7, 0x10, 0x5c, 0xd6, 0xa8, 0x28, 0xe0, 0x39, 0x09, 0xa6, /* |.g..q0..\..(.9..| */
+	0x79, 0x62, 0xe0, 0xea, 0x1f, 0x61, 0xde, 0xb6, 0x49, 0xf6, 0xbc, 0x3f, 0x4c, 0xef, 0x38, 0xc4, /* |yb...a..I..?L.8.| */
+	0xf3, 0x55, 0x04, 0xe5, 0x1e, 0xc1, 0x12, 0xde, 0x5c, 0x38, 0x4d, 0xf7, 0xba, 0x0b, 0x8d, 0x57, /* |.U......\8M....W| */
+	0x8a, 0x4c, 0x70, 0x2b, 0x6b, 0xf1, 0x1d, 0x5f, 0xac, 0x00, 0x00, 0x00, 0x00, /* |.Lp+k.._.....   | */
+}
+
+// TestTeraTestNetGenesisProofOfWork tests that the tera test network genesis
+// block has valid proof of work.
+func TestTeraTestNetGenesisProofOfWork(t *testing.T) {
+	// Get the genesis block
+	genesisBlock := TeraTestNetParams.GenesisBlock
+
+	// Calculate the hash
+	hash := genesisBlock.BlockHash()
+
+	// Get the target from bits
+	bits := genesisBlock.Header.Bits
+	mantissa := bits & 0x00ffffff
+	exponent := bits >> 24
+
+	target := new(big.Int).SetInt64(int64(mantissa))
+	if exponent > 3 {
+		target.Lsh(target, 8*(uint(exponent)-3))
+	}
+
+	// Check if hash meets difficulty
+	hashInt := new(big.Int).SetBytes(hash.CloneBytes())
+
+	if hashInt.Cmp(target) > 0 {
+		t.Fatalf("TestTeraTestNetGenesisProofOfWork: Genesis block does not meet difficulty requirement. "+
+			"Hash: %s, Target: %064x", hash, target.Bytes())
+	}
+
+	// Verify the nonce is the expected value
+	expectedNonce := uint32(0x00000002)
+	if genesisBlock.Header.Nonce != expectedNonce {
+		t.Fatalf("TestTeraTestNetGenesisProofOfWork: Unexpected nonce - got %d, want %d",
+			genesisBlock.Header.Nonce, expectedNonce)
+	}
 }