From 6fad840dd57559f079b1dbd18891aac39da49356 Mon Sep 17 00:00:00 2001
From: Diego <diego2737@gmail.com>
Date: Mon, 23 Sep 2024 12:31:26 -0300
Subject: [PATCH] Implement GetAuthoritesChangesFromBlock

---
 dot/state/block_data.go       | 21 ++++++++++++++++++---
 dot/state/interfaces.go       |  1 +
 dot/state/mocks_test.go       | 15 +++++++++++++++
 internal/database/database.go |  1 +
 internal/database/table.go    |  4 ++++
 lib/grandpa/warp_sync.go      |  1 -
 6 files changed, 39 insertions(+), 4 deletions(-)

diff --git a/dot/state/block_data.go b/dot/state/block_data.go
index d5ec392669..0ae57faf0b 100644
--- a/dot/state/block_data.go
+++ b/dot/state/block_data.go
@@ -5,6 +5,7 @@ package state
 
 import (
 	"github.com/ChainSafe/gossamer/lib/common"
+	"golang.org/x/exp/slices"
 )
 
 // prefixKey = prefix + hash
@@ -88,7 +89,21 @@ func (bs *BlockState) GetJustification(hash common.Hash) ([]byte, error) {
 }
 
 // GetAuthoritesChangesFromBlock retrieves blocks numbers where authority set changes happened
-func (bs *BlockState) GetAuthoritesChangesFromBlock(blockNumber uint) ([]uint, error) {
-	// TODO: complete me
-	panic("not implemented")
+func (bs *BlockState) GetAuthoritesChangesFromBlock(initialBlockNumber uint) ([]uint, error) {
+	blockNumbers := make([]uint, 0)
+	iter, err := bs.db.NewPrefixIterator(setIDChangePrefix)
+	if err != nil {
+		return nil, err
+	}
+
+	for iter.Next() {
+		blockNumber := common.BytesToUint(iter.Value())
+		if blockNumber >= initialBlockNumber {
+			blockNumbers = append(blockNumbers, blockNumber)
+		}
+	}
+
+	// To ensure the order of the blocks
+	slices.Sort(blockNumbers)
+	return blockNumbers, nil
 }
diff --git a/dot/state/interfaces.go b/dot/state/interfaces.go
index 55b3f426fe..bfa630adc4 100644
--- a/dot/state/interfaces.go
+++ b/dot/state/interfaces.go
@@ -21,6 +21,7 @@ type BlockStateDatabase interface {
 	GetPutDeleter
 	Haser
 	NewBatcher
+	NewPrefixIterator(prefix []byte) (database.Iterator, error)
 }
 
 // GetPutter has methods to get and put key values.
diff --git a/dot/state/mocks_test.go b/dot/state/mocks_test.go
index 245d305b73..1ba77e53d9 100644
--- a/dot/state/mocks_test.go
+++ b/dot/state/mocks_test.go
@@ -133,6 +133,21 @@ func (mr *MockBlockStateDatabaseMockRecorder) NewBatch() *gomock.Call {
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "NewBatch", reflect.TypeOf((*MockBlockStateDatabase)(nil).NewBatch))
 }
 
+// NewPrefixIterator mocks base method.
+func (m *MockBlockStateDatabase) NewPrefixIterator(arg0 []byte) (database.Iterator, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "NewPrefixIterator", arg0)
+	ret0, _ := ret[0].(database.Iterator)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// NewPrefixIterator indicates an expected call of NewPrefixIterator.
+func (mr *MockBlockStateDatabaseMockRecorder) NewPrefixIterator(arg0 any) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "NewPrefixIterator", reflect.TypeOf((*MockBlockStateDatabase)(nil).NewPrefixIterator), arg0)
+}
+
 // Put mocks base method.
 func (m *MockBlockStateDatabase) Put(arg0, arg1 []byte) error {
 	m.ctrl.T.Helper()
diff --git a/internal/database/database.go b/internal/database/database.go
index b3140a4623..b827c82d2b 100644
--- a/internal/database/database.go
+++ b/internal/database/database.go
@@ -60,6 +60,7 @@ type Table interface {
 	Path() string
 	NewBatch() Batch
 	NewIterator() (Iterator, error)
+	NewPrefixIterator(prefix []byte) (Iterator, error)
 }
 
 const DefaultDatabaseDir = "db"
diff --git a/internal/database/table.go b/internal/database/table.go
index 3c6eb74793..4e03cb393e 100644
--- a/internal/database/table.go
+++ b/internal/database/table.go
@@ -59,3 +59,7 @@ func (t *table) NewBatch() Batch {
 func (t *table) NewIterator() (Iterator, error) {
 	return t.db.NewPrefixIterator(t.prefix)
 }
+
+func (t *table) NewPrefixIterator(prefix []byte) (Iterator, error) {
+	return t.db.NewPrefixIterator(append(t.prefix, prefix...))
+}
diff --git a/lib/grandpa/warp_sync.go b/lib/grandpa/warp_sync.go
index b586fc6a92..90aab2bc22 100644
--- a/lib/grandpa/warp_sync.go
+++ b/lib/grandpa/warp_sync.go
@@ -45,7 +45,6 @@ func (np *NetworkProvider) Generate(start common.Hash) ([]byte, error) {
 		// the header should contains a standard scheduled change
 		// otherwise  the set must have changed through a forced changed,
 		// in which case we stop collecting proofs as the chain of trust in authority handoffs was broken.
-
 		header, err := np.backend.GetHeaderByNumber(blockNumber)
 		if err != nil {
 			return nil, err