Feat: added colored coins + introduced additional classes

packages/ledgerstate/address.go

 package ledgerstate
 
 type Address struct {
+	hash                   AddressHash
+	unspentTransferOutputs map[TransferHash]*ColoredBalance
+}
+
+func NewAddress(hash AddressHash) *Address {
+	return &Address{
+		hash: hash,
+	}
+}
+
+func (address *Address) GetUnspentTransferOutputs() map[TransferHash]*ColoredBalance {
+	return address.unspentTransferOutputs
+}
+
+func (address *Address) Exists() bool {
+	return address != nil
 }

packages/ledgerstate/colored_balance.go

+package ledgerstate
+
+type ColoredBalance struct {
+	colorHash ColorHash
+	balance   uint64
+}

packages/ledgerstate/ledgerstate.go

@@ -4,3 +4,36 @@ type LedgerState struct {
 	mainReality  *Reality
 	subRealities map[string]*Reality
 }
+
+func NewLedgerState() *LedgerState {
+	return &LedgerState{
+		mainReality:  NewReality(),
+		subRealities: make(map[string]*Reality),
+	}
+}
+
+func (ledgerState *LedgerState) GetUnspentTransferOutputs(address AddressHash, includedSubRealities ...TransferHash) (result map[TransferHash]*ColoredBalance) {
+	result = make(map[TransferHash]*ColoredBalance)
+
+	for _, reality := range ledgerState.getRealities(includedSubRealities...) {
+		if address := reality.GetAddress(address); address.Exists() {
+			for transferHash, coloredBalance := range address.GetUnspentTransferOutputs() {
+				result[transferHash] = coloredBalance
+			}
+		}
+	}
+
+	return
+}
+
+func (ledgerState *LedgerState) getRealities(includedSubRealities ...TransferHash) (realities []*Reality) {
+	realities = append(realities, ledgerState.mainReality)
+
+	for _, subRealityToInclude := range includedSubRealities {
+		if subReality := ledgerState.subRealities[subRealityToInclude]; subReality.Exists() {
+			realities = append(realities, subReality)
+		}
+	}
+
+	return
+}

packages/ledgerstate/ledgerstate_test.go

+package ledgerstate
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestLedgerState_GetUnspentTransferOutputs(t *testing.T) {
+	ledgerState := NewLedgerState()
+
+	NewAddress("ABC")
+
+	fmt.Println(ledgerState.GetUnspentTransferOutputs("ABC"))
+}

packages/ledgerstate/reality.go

 package ledgerstate
 
 type Reality struct {
-	addresses map[string]*Address
+	addresses map[AddressHash]*Address
+}
+
+func NewReality() *Reality {
+	return &Reality{
+		addresses: make(map[AddressHash]*Address),
+	}
+}
+
+func (reality *Reality) GetAddress(address AddressHash) *Address {
+	return reality.addresses[address]
+}
+
+func (reality *Reality) Exists() bool {
+	return reality != nil
 }

packages/ledgerstate/types.go

+package ledgerstate
+
+type AddressHash = string
+
+type TransferHash = string
+
+type ColorHash = string