From 57c75978b69d28154010497ba5420f190856b66c Mon Sep 17 00:00:00 2001
From: Zlatin Balevsky <zlatinb@gmail.com>
Date: Sun, 8 Mar 2020 20:19:37 +0000
Subject: [PATCH] wip on feed manager deserialization

---
 .../core/filefeeds/FeedItemLoadedEvent.groovy |  7 ++
 .../core/filefeeds/FeedLoadedEvent.groovy     |  7 ++
 .../muwire/core/filefeeds/FeedManager.groovy  | 93 +++++++++++++++++++
 3 files changed, 107 insertions(+)
 create mode 100644 core/src/main/groovy/com/muwire/core/filefeeds/FeedItemLoadedEvent.groovy
 create mode 100644 core/src/main/groovy/com/muwire/core/filefeeds/FeedLoadedEvent.groovy
 create mode 100644 core/src/main/groovy/com/muwire/core/filefeeds/FeedManager.groovy

diff --git a/core/src/main/groovy/com/muwire/core/filefeeds/FeedItemLoadedEvent.groovy b/core/src/main/groovy/com/muwire/core/filefeeds/FeedItemLoadedEvent.groovy
new file mode 100644
index 00000000..146f3708
--- /dev/null
+++ b/core/src/main/groovy/com/muwire/core/filefeeds/FeedItemLoadedEvent.groovy
@@ -0,0 +1,7 @@
+package com.muwire.core.filefeeds
+
+import com.muwire.core.Event
+
+class FeedItemLoadedEvent extends Event {
+    FeedItem item
+}
diff --git a/core/src/main/groovy/com/muwire/core/filefeeds/FeedLoadedEvent.groovy b/core/src/main/groovy/com/muwire/core/filefeeds/FeedLoadedEvent.groovy
new file mode 100644
index 00000000..7e92554e
--- /dev/null
+++ b/core/src/main/groovy/com/muwire/core/filefeeds/FeedLoadedEvent.groovy
@@ -0,0 +1,7 @@
+package com.muwire.core.filefeeds
+
+import com.muwire.core.Event
+
+class FeedLoadedEvent extends Event {
+    Feed feed
+}
diff --git a/core/src/main/groovy/com/muwire/core/filefeeds/FeedManager.groovy b/core/src/main/groovy/com/muwire/core/filefeeds/FeedManager.groovy
new file mode 100644
index 00000000..3214b163
--- /dev/null
+++ b/core/src/main/groovy/com/muwire/core/filefeeds/FeedManager.groovy
@@ -0,0 +1,93 @@
+package com.muwire.core.filefeeds
+
+import java.nio.file.Files
+import java.util.concurrent.ConcurrentHashMap
+import java.util.concurrent.ExecutorService
+import java.util.concurrent.Executors
+import java.util.concurrent.ThreadFactory
+
+import com.muwire.core.EventBus
+import com.muwire.core.Persona
+
+import groovy.json.JsonSlurper
+import groovy.util.logging.Log
+
+import net.i2p.data.Base64
+
+@Log
+class FeedManager {
+    
+    private final EventBus eventBus
+    private final File metadataFolder, itemsFolder
+    private final Map<Persona, Feed> feeds = new ConcurrentHashMap<>()
+    private final Map<Persona, Set<FeedItem>> feedItems = new ConcurrentHashMap<>()
+    
+    private final ExecutorService persister = Executors.newSingleThreadExecutor({r ->
+        new Thread(r, "feed persister")
+    } as ThreadFactory)
+    
+    
+    FeedManager(EventBus eventBus, File home) {
+        this.eventBus = eventBus
+        File feedsFolder = new File(home, "filefeeds")
+        if (!feedsFolder.exists())
+            feedsFolder.mkdir()
+        this.metadataFolder = new File(feedsFolder, "metadata")
+        if (!metadataFolder.exists())
+            metadataFolder.mkdir()
+        this.itemsFolder = new File(feedsFolder, "items")
+        if (!itemsFolder.exists())
+            itemsFolder.mkdir()
+    }
+    
+    void start() {
+        log.info("starting feed manager")
+        persister.submit({loadFeeds()} as Runnable)
+        persister.submit({loadItems()} as Runnable)
+    }
+    
+    void stop() {
+        persister.shutdown()
+    }
+    
+    private void loadFeeds() {
+        def slurper = new JsonSlurper()
+        Files.walk(metadataFolder.toPath()).
+            filter( { it.getFileName().toString().endsWith(".json")}).
+            forEach( {
+                def parsed = slurper.parse(it.toFile())
+                Persona publisher = new Persona(new ByteArrayInputStream(Base64.decode(parsed.publisher)))
+                Feed feed = new Feed(publisher)
+                feed.setUpdateInterval(parsed.updateInterval)
+                feed.setLastUpdated(parsed.lastUpdated)
+                feed.setItemsToKeep(parsed.itemsToKeep)
+                feed.setAutoDownload(parsed.autoDownload)
+                
+                feeds.put(feed.getPublisher(), feed)
+                
+                eventBus.publish(new FeedLoadedEvent(feed : feed))
+            })     
+    }
+    
+    private void loadItems() {
+        def slurper = new JsonSlurper()
+        feeds.keySet().each {
+            File itemsFile = new File(itemsFolder, it.destination.toBase32() + ".json")
+            if (!itemsFile.exists())
+                return // no items yet?
+            itemsFile.eachLine { line ->
+                def parsed = slurper.parse(line)
+                FeedItem item = FeedItems.objToFeedItem(parsed, it)
+                
+                Set<FeedItem> items = feedItems.get(it)
+                if (items == null) {
+                    items = new HashSet<>()
+                    feedItems.put(it, items)
+                }
+                items.add(item)
+                
+                eventBus.publish(new FeedItemLoadedEvent(item : item))
+            }
+        }
+    }
+}