1 files changed, 120 insertions, 0 deletions
diff --git a/weed/admin/topology/structs.go b/weed/admin/topology/structs.go
new file mode 100644
index 000000000..f2d29eb5f
--- /dev/null
+++ b/weed/admin/topology/structs.go
@@ -0,0 +1,120 @@
+package topology
+
+import (
+	"sync"
+	"time"
+
+	"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
+)
+
+// TaskSource represents a single source in a multi-source task (for replicated volume cleanup)
+type TaskSource struct {
+	SourceServer  string            `json:"source_server"`
+	SourceDisk    uint32            `json:"source_disk"`
+	StorageChange StorageSlotChange `json:"storage_change"` // Storage impact on this source
+	EstimatedSize int64             `json:"estimated_size"` // Estimated size for this source
+}
+
+// TaskDestination represents a single destination in a multi-destination task
+type TaskDestination struct {
+	TargetServer  string            `json:"target_server"`
+	TargetDisk    uint32            `json:"target_disk"`
+	StorageChange StorageSlotChange `json:"storage_change"` // Storage impact on this destination
+	EstimatedSize int64             `json:"estimated_size"` // Estimated size for this destination
+}
+
+// taskState represents the current state of tasks affecting the topology (internal)
+// Uses unified multi-source/multi-destination design:
+// - Single-source tasks (balance, vacuum, replication): 1 source, 1 destination
+// - Multi-source EC tasks (replicated volumes): N sources, M destinations
+type taskState struct {
+	VolumeID      uint32     `json:"volume_id"`
+	TaskType      TaskType   `json:"task_type"`
+	Status        TaskStatus `json:"status"`
+	StartedAt     time.Time  `json:"started_at"`
+	CompletedAt   time.Time  `json:"completed_at,omitempty"`
+	EstimatedSize int64      `json:"estimated_size"` // Total estimated size of task
+
+	// Unified source and destination arrays (always used)
+	Sources      []TaskSource      `json:"sources"`      // Source locations (1+ for all task types)
+	Destinations []TaskDestination `json:"destinations"` // Destination locations (1+ for all task types)
+}
+
+// DiskInfo represents a disk with its current state and ongoing tasks (public for external access)
+type DiskInfo struct {
+	NodeID     string              `json:"node_id"`
+	DiskID     uint32              `json:"disk_id"`
+	DiskType   string              `json:"disk_type"`
+	DataCenter string              `json:"data_center"`
+	Rack       string              `json:"rack"`
+	DiskInfo   *master_pb.DiskInfo `json:"disk_info"`
+	LoadCount  int                 `json:"load_count"` // Number of active tasks
+}
+
+// activeDisk represents internal disk state (private)
+type activeDisk struct {
+	*DiskInfo
+	pendingTasks  []*taskState
+	assignedTasks []*taskState
+	recentTasks   []*taskState // Completed in last N seconds
+}
+
+// activeNode represents a node with its disks (private)
+type activeNode struct {
+	nodeID     string
+	dataCenter string
+	rack       string
+	nodeInfo   *master_pb.DataNodeInfo
+	disks      map[uint32]*activeDisk // DiskID -> activeDisk
+}
+
+// ActiveTopology provides a real-time view of cluster state with task awareness
+type ActiveTopology struct {
+	// Core topology from master
+	topologyInfo *master_pb.TopologyInfo
+	lastUpdated  time.Time
+
+	// Structured topology for easy access (private)
+	nodes map[string]*activeNode // NodeID -> activeNode
+	disks map[string]*activeDisk // "NodeID:DiskID" -> activeDisk
+
+	// Performance indexes for O(1) lookups (private)
+	volumeIndex  map[uint32][]string // VolumeID -> list of "NodeID:DiskID" where volume replicas exist
+	ecShardIndex map[uint32][]string // VolumeID -> list of "NodeID:DiskID" where EC shards exist
+
+	// Task states affecting the topology (private)
+	pendingTasks  map[string]*taskState
+	assignedTasks map[string]*taskState
+	recentTasks   map[string]*taskState
+
+	// Configuration
+	recentTaskWindowSeconds int
+
+	// Synchronization
+	mutex sync.RWMutex
+}
+
+// DestinationPlan represents a planned destination for a volume/shard operation
+type DestinationPlan struct {
+	TargetNode     string   `json:"target_node"`
+	TargetDisk     uint32   `json:"target_disk"`
+	TargetRack     string   `json:"target_rack"`
+	TargetDC       string   `json:"target_dc"`
+	ExpectedSize   uint64   `json:"expected_size"`
+	PlacementScore float64  `json:"placement_score"`
+	Conflicts      []string `json:"conflicts"`
+}
+
+// MultiDestinationPlan represents multiple planned destinations for operations like EC
+type MultiDestinationPlan struct {
+	Plans          []*DestinationPlan `json:"plans"`
+	TotalShards    int                `json:"total_shards"`
+	SuccessfulRack int                `json:"successful_racks"`
+	SuccessfulDCs  int                `json:"successful_dcs"`
+}
+
+// VolumeReplica represents a replica location with server and disk information
+type VolumeReplica struct {
+	ServerID string `json:"server_id"`
+	DiskID   uint32 `json:"disk_id"`
+}