refactor

ots/operation.go

@@ -0,0 +1,34 @@
+package ots
+
+import "crypto/sha256"
+
+type Operation struct {
+	Name   string
+	Tag    byte
+	Binary bool // it's an operation that takes one argument, otherwise takes none
+	Apply  func(curr []byte, arg []byte) []byte
+}
+
+var Tags = map[byte]*Operation{
+	0xf0: {"append", 0xf0, true, func(curr []byte, arg []byte) []byte {
+		result := make([]byte, len(curr)+len(arg))
+		copy(result[0:], curr)
+		copy(result[len(curr):], arg)
+		return result
+	}},
+	0xf1: {"prepend", 0xf1, true, func(curr []byte, arg []byte) []byte {
+		result := make([]byte, len(curr)+len(arg))
+		copy(result[0:], arg)
+		copy(result[len(arg):], curr)
+		return result
+	}},
+	0xf2: {"reverse", 0xf2, false, func(curr []byte, arg []byte) []byte { panic("reverse not implemented") }},
+	0xf3: {"hexlify", 0xf3, false, func(curr []byte, arg []byte) []byte { panic("hexlify not implemented") }},
+	0x02: {"sha1", 0x02, false, func(curr []byte, arg []byte) []byte { panic("sha1 not implemented") }},
+	0x03: {"ripemd160", 0x03, false, ripemd160},
+	0x08: {"sha256", 0x08, false, func(curr []byte, arg []byte) []byte {
+		v := sha256.Sum256(curr)
+		return v[:]
+	}},
+	0x67: {"keccak256", 0x67, false, func(curr []byte, arg []byte) []byte { panic("keccak256 not implemented") }},
+}