1 files changed, 185 insertions, 10 deletions

diff --git a/common/natspec/natspec.go b/common/natspec/natspec.go
index 8e6568cef..38e7c1a9d 100644
--- a/common/natspec/natspec.go
+++ b/common/natspec/natspec.go
@@ -1,20 +1,137 @@
 package natspec
 
 import (
+	"bytes"
+	"encoding/json"
 	"fmt"
 	"github.com/robertkrimen/otto"
+	"strings"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/docserver"
+	"github.com/ethereum/go-ethereum/common/resolver"
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/xeth"
 )
 
+type abi2method map[[8]byte]*method
+
 type NatSpec struct {
-	jsvm *otto.Otto
+	jsvm                    *otto.Otto
+	userDocJson, abiDocJson []byte
+	userDoc                 userDoc
+	tx, data                string
+	// abiDoc abiDoc
+}
+
+func getFallbackNotice(comment, tx string) string {
+
+	return "About to submit transaction (" + comment + "): " + tx
+
 }
 
-// TODO: should initialise with abi and userdoc jsons
-func New() (self *NatSpec, err error) {
+func GetNotice(xeth *xeth.XEth, tx string, http *docserver.DocServer) (notice string) {
+
+	ns, err := New(xeth, tx, http)
+	if err != nil {
+		if ns == nil {
+			return getFallbackNotice("no NatSpec info found for contract", tx)
+		} else {
+			return getFallbackNotice("invalid NatSpec info", tx)
+		}
+	}
+
+	notice, err2 := ns.Notice()
+
+	if err2 != nil {
+		return getFallbackNotice("NatSpec notice error \""+err2.Error()+"\"", tx)
+	}
+
+	return
+
+}
+
+func New(xeth *xeth.XEth, tx string, http *docserver.DocServer) (self *NatSpec, err error) {
+
+	// extract contract address from tx
+
+	var obj map[string]json.RawMessage
+	err = json.Unmarshal([]byte(tx), &obj)
+	if err != nil {
+		return
+	}
+	var tmp []map[string]string
+	err = json.Unmarshal(obj["params"], &tmp)
+	if err != nil {
+		return
+	}
+	contractAddress := tmp[0]["to"]
 
-	self = new(NatSpec)
-	self.jsvm = otto.New()
+	// retrieve contract hash from state
+	if !xeth.IsContract(contractAddress) {
+		err = fmt.Errorf("NatSpec error: contract not found")
+		return
+	}
+	codehex := xeth.CodeAt(contractAddress)
+	codeHash := common.BytesToHash(crypto.Sha3(common.Hex2Bytes(codehex[2:])))
+	// parse out host/domain
 
+	// set up nameresolver with natspecreg + urlhint contract addresses
+	res := resolver.New(
+		xeth,
+		resolver.URLHintContractAddress,
+		resolver.HashRegContractAddress,
+	)
+
+	// resolve host via HashReg/UrlHint Resolver
+	uri, hash, err := res.KeyToUrl(codeHash)
+	if err != nil {
+		return
+	}
+
+	// get content via http client and authenticate content using hash
+	content, err := http.GetAuthContent(uri, hash)
+	if err != nil {
+		return
+	}
+
+	// get abi, userdoc
+	var obj2 map[string]json.RawMessage
+	err = json.Unmarshal(content, &obj2)
+	if err != nil {
+		return
+	}
+
+	abi := []byte(obj2["abi"])
+	userdoc := []byte(obj2["userdoc"])
+
+	self, err = NewWithDocs(abi, userdoc, tx)
+	return
+}
+
+func NewWithDocs(abiDocJson, userDocJson []byte, tx string) (self *NatSpec, err error) {
+
+	var obj map[string]json.RawMessage
+	err = json.Unmarshal([]byte(tx), &obj)
+	if err != nil {
+		return
+	}
+	var tmp []map[string]string
+	err = json.Unmarshal(obj["params"], &tmp)
+	if err != nil {
+		return
+	}
+	data := tmp[0]["data"]
+
+	self = &NatSpec{
+		jsvm:        otto.New(),
+		abiDocJson:  abiDocJson,
+		userDocJson: userDocJson,
+		tx:          tx,
+		data:        data,
+	}
+
+	// load and require natspec js (but it is meant to be protected environment)
 	_, err = self.jsvm.Run(natspecJS)
 	if err != nil {
 		return
@@ -24,20 +141,78 @@ func New() (self *NatSpec, err error) {
 		return
 	}
 
+	err = json.Unmarshal(userDocJson, &self.userDoc)
+	// err = parseAbiJson(abiDocJson, &self.abiDoc)
+
 	return
 }
 
-func (self *NatSpec) Notice(transaction, abi, method, expression string) (string, error) {
-	var err error
-	if _, err = self.jsvm.Run("var transaction = " + transaction + ";"); err != nil {
+// type abiDoc []method
+
+// type method struct {
+// 	Name   string  `json:name`
+// 	Inputs []input `json:inputs`
+// 	abiKey [8]byte
+// }
+
+// type input struct {
+// 	Name string `json:name`
+// 	Type string `json:type`
+// }
+
+// json skeleton for abi doc (contract method definitions)
+type method struct {
+	Notice string `json:notice`
+	name   string
+}
+
+type userDoc struct {
+	Methods map[string]*method `json:methods`
+}
+
+func (self *NatSpec) makeAbi2method(abiKey [8]byte) (meth *method) {
+	for signature, m := range self.userDoc.Methods {
+		name := strings.Split(signature, "(")[0]
+		hash := []byte(common.Bytes2Hex(crypto.Sha3([]byte(signature))))
+		var key [8]byte
+		copy(key[:], hash[:8])
+		if bytes.Equal(key[:], abiKey[:]) {
+			meth = m
+			meth.name = name
+			return
+		}
+	}
+	return
+}
+
+func (self *NatSpec) Notice() (notice string, err error) {
+	var abiKey [8]byte
+	if len(self.data) < 10 {
+		err = fmt.Errorf("Invalid transaction data")
+		return
+	}
+	copy(abiKey[:], self.data[2:10])
+	meth := self.makeAbi2method(abiKey)
+
+	if meth == nil {
+		err = fmt.Errorf("abi key does not match any method")
+		return
+	}
+	notice, err = self.noticeForMethod(self.tx, meth.name, meth.Notice)
+	return
+}
+
+func (self *NatSpec) noticeForMethod(tx string, name, expression string) (notice string, err error) {
+
+	if _, err = self.jsvm.Run("var transaction = " + tx + ";"); err != nil {
 		return "", fmt.Errorf("natspec.js error setting transaction: %v", err)
 	}
 
-	if _, err = self.jsvm.Run("var abi = " + abi + ";"); err != nil {
+	if _, err = self.jsvm.Run("var abi = " + string(self.abiDocJson) + ";"); err != nil {
 		return "", fmt.Errorf("natspec.js error setting abi: %v", err)
 	}
 
-	if _, err = self.jsvm.Run("var method = '" + method + "';"); err != nil {
+	if _, err = self.jsvm.Run("var method = '" + name + "';"); err != nil {
 		return "", fmt.Errorf("natspec.js error setting method: %v", err)
 	}