Merge pull request #1 from BitcoinSchema/from-bpu

From bpu

bob.go

@@ -0,0 +1,56 @@
+package sigma
+
+import (
+	"strconv"
+
+	"github.com/bitcoinschema/go-bpu"
+)
+
+func NewSigFromTape(tape bpu.Tape, vout int) (s *Sig) {
+	s = new(Sig)
+	s.FromTape(tape, vout)
+	return
+}
+
+// FromTape takes a BOB Tape and returns an Aip data structure.
+// Using the FromTape() alone will prevent validation (data is needed via SetData to enable)
+func (s *Sig) FromTape(tape bpu.Tape, vout int) {
+
+	// Not a valid tape?
+	if len(tape.Cell) < 4 {
+		return
+	}
+
+	// Loop to find start of AIP
+	var startIndex int
+	found := false
+	for i, cell := range tape.Cell {
+		if *cell.S == Prefix {
+			startIndex = i
+			found = true
+			break
+		}
+	}
+
+	if !found || len(tape.Cell) < 5 {
+		return
+	}
+	s.TargetVout = vout
+	// Set the SIGMA fields
+	if tape.Cell[startIndex+1].S != nil {
+		s.Algorithm = Algorithm(*tape.Cell[startIndex+1].S)
+	}
+	if tape.Cell[startIndex+2].S != nil {
+		s.Address = *tape.Cell[startIndex+2].S
+	}
+	if tape.Cell[startIndex+3].B != nil {
+		s.Signature = *tape.Cell[startIndex+3].B
+	}
+	if tape.Cell[startIndex+4].S != nil {
+		vin, err := strconv.Atoi(*tape.Cell[startIndex+4].S)
+		if err != nil {
+			return
+		}
+		s.Vin = int(vin)
+	}
+}

go.mod

@@ -2,7 +2,10 @@ module github.com/bitcoinschema/go-sigma
 
 go 1.21.3
 
-require github.com/libsv/go-bt/v2 v2.2.5
+require (
+	github.com/bitcoinschema/go-bpu v0.1.3
+	github.com/libsv/go-bt/v2 v2.2.5
+)
 
 require (
 	github.com/bitcoinsv/bsvd v0.0.0-20190609155523-4c29707f7173 // indirect

go.sum

@@ -1,5 +1,7 @@
 github.com/bitcoinschema/go-bitcoin/v2 v2.0.5 h1:Sgh5Eb746Zck/46rFDrZZEXZWyO53fMuWYhNoZa1tck=
 github.com/bitcoinschema/go-bitcoin/v2 v2.0.5/go.mod h1:JjO1ivfZv6vhK0uAXzyH08AAHlzNMAfnyK1Fiv9r4ZA=
+github.com/bitcoinschema/go-bpu v0.1.3 h1:O7SvuptH4Q7hemD6G9OotPLINZ61CAVOgWKJWKM+edY=
+github.com/bitcoinschema/go-bpu v0.1.3/go.mod h1:y4ZEDC0fSYRrA6N6bzKwHXdtMrRiQhpurpkTVobz07I=
 github.com/bitcoinsv/bsvd v0.0.0-20190609155523-4c29707f7173 h1:2yTIV9u7H0BhRDGXH5xrAwAz7XibWJtX2dNezMeNsUo=
 github.com/bitcoinsv/bsvd v0.0.0-20190609155523-4c29707f7173/go.mod h1:BZ1UcC9+tmcDEcdVXgpt13hMczwJxWzpAn68wNs7zRA=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=

sigma.go

@@ -17,6 +17,7 @@ import (
 
 type Algorithm string
 
+const Prefix = "SIGMA"
 const sigmaHex = "5349474d41"
 const (
 	BSM Algorithm = "BSM"