From 7cd41ac45aed7ee22ef02f8abedf83a2914c4807 Mon Sep 17 00:00:00 2001
From: obscuren <obscuren@obscura.com>
Date: Fri, 3 Jan 2014 00:43:49 +0100
Subject: [PATCH] Wip VM. Created contracts

---
 block.go         | 26 +++++++++++++++++++++++++-
 block_manager.go | 10 ++++------
 contract.go      | 40 ++++++++++++++++++++++++++++++++++++++++
 transaction.go   | 11 ++++++-----
 trie.go          |  2 +-
 vm_test.go       |  9 ++++-----
 6 files changed, 80 insertions(+), 18 deletions(-)
 create mode 100644 contract.go

diff --git a/block.go b/block.go
index 146328471..dd329f8ac 100644
--- a/block.go
+++ b/block.go
@@ -4,6 +4,7 @@ import (
   _"fmt"
   "time"
   _"bytes"
+  _"encoding/hex"
 )
 
 type Block struct {
@@ -63,13 +64,36 @@ func CreateBlock(root string, num int, prevHash string, base string, difficulty
     extra: extra,
   }
   block.state = NewTrie(Db, root)
+
   for _, tx := range txes {
-    block.state.Update(tx.recipient, string(tx.MarshalRlp()))
+    // Create contract if there's no recipient
+    if tx.recipient == "" {
+      addr := tx.Hash()
+
+      contract := NewContract(tx.value, []byte(""))
+      block.state.Update(string(addr), string(contract.MarshalRlp()))
+      for i, val := range tx.data {
+        contract.state.Update(string(Encode(i)), val)
+      }
+      block.UpdateContract(addr, contract)
+    }
   }
 
   return block
 }
 
+func (block *Block) GetContract(addr []byte) *Contract {
+  data := block.state.Get(string(addr))
+  contract := &Contract{}
+  contract.UnmarshalRlp([]byte(data))
+
+  return contract
+}
+
+func (block *Block) UpdateContract(addr []byte, contract *Contract) {
+  block.state.Update(string(addr), string(contract.MarshalRlp()))
+}
+
 func (block *Block) Update() {
 }
 
diff --git a/block_manager.go b/block_manager.go
index 0ef5d1108..f3aa29ba4 100644
--- a/block_manager.go
+++ b/block_manager.go
@@ -45,13 +45,11 @@ func (bm *BlockManager) ProcessBlock(block *Block) error {
 }
 
 func (bm *BlockManager) ProcessTransaction(tx *Transaction, block *Block, lockChan chan bool) {
-  if tx.recipient == "\x00" {
-    bm.vm.RunTransaction(tx, block, func(opType OpType) bool {
-      // TODO calculate fees
+  bm.vm.RunTransaction(tx, block, func(opType OpType) bool {
+    // TODO calculate fees
 
-      return true // Continue
-    })
-  }
+    return true // Continue
+  })
 
   // Broadcast we're done
   lockChan <- true
diff --git a/contract.go b/contract.go
new file mode 100644
index 000000000..e95e50b74
--- /dev/null
+++ b/contract.go
@@ -0,0 +1,40 @@
+package main
+
+import (
+)
+
+type Contract struct {
+  active int
+  amount uint32 // ???
+  state  *Trie
+}
+func NewContract(amount uint32, root []byte) *Contract {
+  contract := &Contract{active: 1, amount: amount}
+  contract.state = NewTrie(Db, string(root))
+
+  return  contract
+}
+func (c *Contract) MarshalRlp() []byte {
+  // Prepare the transaction for serialization
+  preEnc := []interface{}{uint32(c.active), c.amount, c.state.root}
+
+  return Encode(preEnc)
+}
+
+func (c *Contract) UnmarshalRlp(data []byte) {
+  t, _ := Decode(data, 0)
+
+  if slice, ok := t.([]interface{}); ok {
+    if active, ok := slice[0].(uint8); ok {
+      c.active = int(active)
+    }
+
+    if amount, ok := slice[1].(uint8); ok {
+      c.amount = uint32(amount)
+    }
+
+    if root, ok := slice[2].([]uint8); ok {
+      c.state = NewTrie(Db, string(root))
+    }
+  }
+}
diff --git a/transaction.go b/transaction.go
index 562593c96..dc5204f9b 100644
--- a/transaction.go
+++ b/transaction.go
@@ -3,8 +3,8 @@ package main
 import (
   "math/big"
   "fmt"
-  "encoding/hex"
-  "crypto/sha256"
+  _"encoding/hex"
+  _"crypto/sha256"
   _ "bytes"
 )
 
@@ -63,13 +63,14 @@ func NewTransaction(to string, value uint32, data []string) *Transaction {
     tx.data[i] = instr
   }
 
-  b:= []byte(tx.MarshalRlp())
-  hash := sha256.Sum256(b)
-  tx.addr = hex.EncodeToString(hash[0:19])
 
   return &tx
 }
 
+func (tx *Transaction) Hash() []byte {
+  return Sha256Bin(tx.MarshalRlp())
+}
+
 func (tx *Transaction) MarshalRlp() []byte {
   // Prepare the transaction for serialization
   preEnc := []interface{}{
diff --git a/trie.go b/trie.go
index 83a3073ae..442cc08b8 100644
--- a/trie.go
+++ b/trie.go
@@ -48,7 +48,7 @@ type Trie struct {
 }
 
 func NewTrie(db Database, root string) *Trie {
-  return &Trie{db: db, root: ""}
+  return &Trie{db: db, root: root}
 }
 
 /*
diff --git a/vm_test.go b/vm_test.go
index d0bcda2ca..00b8809a1 100644
--- a/vm_test.go
+++ b/vm_test.go
@@ -3,7 +3,6 @@ package main
 import (
   "fmt"
   "testing"
-  _"encoding/hex"
 )
 
 
@@ -11,7 +10,7 @@ func TestVm(t *testing.T) {
   db, _ := NewMemDatabase()
   Db = db
 
-  tx := NewTransaction("\x00", 20, []string{
+  tx := NewTransaction("", 20, []string{
     "PSH 10",
   })
 
@@ -20,8 +19,8 @@ func TestVm(t *testing.T) {
 
   bm := NewBlockManager()
   bm.ProcessBlock( block )
-  tx1 := &Transaction{}
-  tx1.UnmarshalRlp([]byte(block.state.Get(tx.recipient)))
-  fmt.Println(tx1)
+  contract := block.GetContract(tx.Hash())
+  fmt.Println(contract)
+  fmt.Println("it is", contract.state.Get(string(Encode(0))))
 }