From e0c76b4e3082ab8e373ec65c9af8f7b61e72941c Mon Sep 17 00:00:00 2001
From: Wesley Graham <wgraham@berkeley.edu>
Date: Fri, 3 Jan 2020 14:30:16 -0800
Subject: [PATCH] sig query (#161)

---
 cmd/plasmacli/subcmd/eth/query/confirmsig.go | 91 ++++++++++++++++++++
 cmd/plasmacli/subcmd/eth/query/root.go       |  2 +
 2 files changed, 93 insertions(+)
 create mode 100644 cmd/plasmacli/subcmd/eth/query/confirmsig.go

diff --git a/cmd/plasmacli/subcmd/eth/query/confirmsig.go b/cmd/plasmacli/subcmd/eth/query/confirmsig.go
new file mode 100644
index 0000000..5936e31
--- /dev/null
+++ b/cmd/plasmacli/subcmd/eth/query/confirmsig.go
@@ -0,0 +1,91 @@
+package query
+
+import (
+	"encoding/json"
+	"fmt"
+	"github.com/FourthState/plasma-mvp-sidechain/cmd/plasmacli/config"
+	"github.com/FourthState/plasma-mvp-sidechain/plasma"
+	"github.com/FourthState/plasma-mvp-sidechain/store"
+	"github.com/cosmos/cosmos-sdk/client/context"
+	"github.com/ethereum/go-ethereum/rlp"
+	"github.com/spf13/cobra"
+)
+
+// SigCmd returns the query confirm sig command
+func SigCmd() *cobra.Command {
+	config.AddPersistentTMFlags(sigCmd)
+	sigCmd.Flags().Bool(useNodeF, false, "trust connected full node")
+	return sigCmd
+}
+
+var sigCmd = &cobra.Command{
+	Use:   "sig <position>",
+	Short: "Query confirm signature information for a given position",
+	Args:  cobra.ExactArgs(1),
+	RunE: func(cmd *cobra.Command, args []string) error {
+		// parse position
+		pos, err := plasma.FromPositionString(args[0])
+		if err != nil {
+			return err
+		}
+
+		var sigs []byte
+		ctx := context.NewCLIContext()
+		sigs, err = getSigs(ctx, pos)
+		if err != nil {
+			return fmt.Errorf("failed to retrieve confirm signature information: %s", err)
+		}
+
+		switch len(sigs) {
+		case 65:
+			fmt.Printf("Confirmation Signatures: 0x%x\n", sigs[:])
+		case 130:
+			fmt.Printf("Confirmation Signatures: 0x%x, 0x%x\n", sigs[:65], sigs[65:])
+		}
+
+		return nil
+	},
+}
+
+// Returns confirm sig results for given position
+// Trusts connected full node
+func getSigs(ctx context.CLIContext, position plasma.Position) ([]byte, error) {
+	key := store.GetOutputKey(position)
+	hash, err := ctx.QueryStore(key, store.DataStoreName)
+	if err != nil {
+		return nil, err
+	}
+
+	txKey := store.GetTxKey(hash)
+	txBytes, err := ctx.QueryStore(txKey, store.DataStoreName)
+
+	var tx store.Transaction
+	if err := rlp.DecodeBytes(txBytes, &tx); err != nil {
+		return nil, fmt.Errorf("transaction decoding failed: %s", err.Error())
+	}
+
+	// Look for confirmation signatures
+	// Ignore error if no confirm sig currently exists in store
+	var sigs []byte
+	if len(tx.SpenderTxs[position.OutputIndex]) > 0 {
+		queryPath := fmt.Sprintf("custom/data/tx/%s", tx.SpenderTxs[position.OutputIndex])
+		data, err := ctx.Query(queryPath, nil)
+		if err != nil {
+			return nil, err
+		}
+
+		var spenderTx store.Transaction
+		if err := json.Unmarshal(data, &spenderTx); err != nil {
+			return nil, fmt.Errorf("unmarshaling json query response: %s", err)
+		}
+		for _, input := range spenderTx.Transaction.Inputs {
+			if input.Position.String() == position.String() {
+				for _, sig := range input.ConfirmSignatures {
+					sigs = append(sigs, sig[:]...)
+				}
+			}
+		}
+	}
+
+	return sigs, nil
+}
diff --git a/cmd/plasmacli/subcmd/eth/query/root.go b/cmd/plasmacli/subcmd/eth/query/root.go
index 280e772..3b43e82 100644
--- a/cmd/plasmacli/subcmd/eth/query/root.go
+++ b/cmd/plasmacli/subcmd/eth/query/root.go
@@ -16,6 +16,7 @@ var (
 	indexF    = "index"
 	limitF    = "limit"
 	positionF = "position"
+	useNodeF  = "use-node"
 )
 
 // RootCmd returns the eth query command
@@ -25,6 +26,7 @@ func RootCmd() *cobra.Command {
 		BlockCmd(),
 		DepositCmd(),
 		ExitsCmd(),
+		SigCmd(),
 		RootchainCmd(),
 	)