skeleton of mesh manager

core/src/main/groovy/com/muwire/core/Core.groovy

@@ -29,6 +29,7 @@ import com.muwire.core.files.DirectoryWatcher
 import com.muwire.core.hostcache.CacheClient
 import com.muwire.core.hostcache.HostCache
 import com.muwire.core.hostcache.HostDiscoveredEvent
+import com.muwire.core.mesh.MeshManager
 import com.muwire.core.search.QueryEvent
 import com.muwire.core.search.ResultsEvent
 import com.muwire.core.search.ResultsSender
@@ -166,6 +167,10 @@ public class Core {
 		eventBus.register(FileDownloadedEvent.class, fileManager)
 		eventBus.register(FileUnsharedEvent.class, fileManager)
 		eventBus.register(SearchEvent.class, fileManager)
+        
+        log.info("initializing mesh manager")
+        MeshManager meshManager = new MeshManager(fileManager)
+        eventBus.register(SourceDiscoveredEvent.class, meshManager)
 		
 		log.info "initializing persistence service"
 		persisterService = new PersisterService(new File(home, "files.json"), eventBus, 15000, fileManager)

core/src/main/groovy/com/muwire/core/mesh/Mesh.groovy

@@ -0,0 +1,19 @@
+package com.muwire.core.mesh
+
+import com.muwire.core.InfoHash
+
+import com.muwire.core.download.Pieces
+
+import net.i2p.data.Destination
+import net.i2p.util.ConcurrentHashSet
+
+class Mesh {
+    private final InfoHash infoHash
+    private final Set<Destination> sources = new ConcurrentHashSet<>()
+    private final Pieces pieces
+    
+    Mesh(InfoHash infoHash, Pieces pieces) {
+        this.infoHash = infoHash
+        this.pieces = pieces
+    }
+}

core/src/main/groovy/com/muwire/core/mesh/MeshManager.groovy

@@ -0,0 +1,43 @@
+package com.muwire.core.mesh
+
+import com.muwire.core.Constants
+import com.muwire.core.InfoHash
+import com.muwire.core.download.Pieces
+import com.muwire.core.download.SourceDiscoveredEvent
+import com.muwire.core.files.FileManager
+
+class MeshManager {
+    
+    private final Map<InfoHash, Mesh> meshes = Collections.synchronizedMap(new HashMap<>())
+    private final FileManager fileManager
+    
+    MeshManager(FileManager fileManager) {
+        this.fileManager = fileManager
+    }
+    
+    Mesh get(InfoHash infoHash) {
+        meshes.get(infoHash)
+    }
+    
+    Mesh getOrCreate(InfoHash infoHash, int nPieces) {
+        synchronized(meshes) {
+            if (meshes.containsKey(infoHash))
+                return meshes.get(infoHash)
+            Pieces pieces = new Pieces(nPieces, Constants.DOWNLOAD_SEQUENTIAL_RATIO)
+            if (fileManager.rootToFiles.containsKey(infoHash)) {
+                for (int i = 0; i < nPieces; i++)
+                    pieces.markDownloaded(i)
+            }
+            Mesh rv = new Mesh(infoHash, pieces)
+            meshes.put(infoHash, rv)
+            return rv
+        }
+    }
+    
+    void onSourceDiscoveredEvent(SourceDiscoveredEvent e) {
+        Mesh mesh = meshes.get(e.infoHash)
+        if (mesh == null)
+            return
+        mesh.sources.add(e.source.destination)
+    }
+}