altoslib: Fix map preloading callbacks, run in separate thread

The map storage and tile callbacks were muddled together. Create
clearly separate states for map data and have status updates be
delivered when registering for new status events so that registration
is sufficient to track the state without an explicit call to get the
current state.

Run the map tile creation in a separate thread so that even checking
status of files on disk runs out of the UI thread.

These fixes serve to make the pacifier update more smoothly, and also
not over/under count tile loading so that the loading actually
completes when all of the tiles are loaded.

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 22 insertions, 56 deletions

diff --git a/altoslib/AltosMapCache.java b/altoslib/AltosMapCache.java
index 17a36ff3..38e0f769 100644
--- a/altoslib/AltosMapCache.java
+++ b/altoslib/AltosMapCache.java
@@ -23,25 +23,20 @@ import java.net.*;
 public class AltosMapCache implements AltosMapCacheListener {
 
 	/* An entry in the MapCache */
-	class MapCacheElement implements AltosMapStoreListener {
+	class MapCacheElement implements AltosMapTileListener {
 
 		AltosMapTile		tile;		/* Notify when image has been loaded */
 		AltosImage		image;
-		AltosMapStore		store;
 		long			used;
 
 		class loader implements Runnable {
 			public void run() {
-				if (image != null)
-					tile.notify_image(image);
-				try {
-					image = map_interface.load_image(store.file);
-				} catch (Exception ex) {
+				if (image == null) {
+					try {
+						image = map_interface.load_image(tile.store.file);
+					} catch (Exception ex) {
+					}
 				}
-				if (image == null)
-					tile.set_status(AltosMapTile.failed);
-				else
-					tile.set_status(AltosMapTile.success);
 				tile.notify_image(image);
 			}
 		}
@@ -60,41 +55,21 @@ public class AltosMapCache implements AltosMapCacheListener {
 		}
 
 		public boolean has_map() {
-			return store.status() == AltosMapTile.success;
+			return tile.status == AltosMapTile.loaded;
 		}
 
-		public synchronized void notify_store(AltosMapStore store, int status) {
-			switch (status) {
-			case AltosMapTile.loading:
-				break;
-			case AltosMapTile.success:
+		public synchronized void notify_tile(AltosMapTile tile, int status) {
+			if (status == AltosMapTile.fetched) {
+				System.out.printf("tile fetched, loading image\n");
 				load();
-				break;
-			default:
-				tile.set_status(status);
-				tile.notify_image(null);
 			}
 		}
 
-		public MapCacheElement(AltosMapTile tile, AltosMapStore store) throws IOException {
+		public MapCacheElement(AltosMapTile tile) {
 			this.tile = tile;
 			this.image = null;
-			this.store = store;
 			this.used = 0;
-
-			int status = store.status();
-			switch (status) {
-			case AltosMapTile.loading:
-				store.add_listener(this);
-				break;
-			case AltosMapTile.success:
-				load();
-				break;
-			default:
-				tile.set_status(status);
-				tile.notify_image(null);
-				break;
-			}
+			tile.add_listener(this);
 		}
 	}
 
@@ -135,7 +110,7 @@ public class AltosMapCache implements AltosMapCacheListener {
 		}
 	}
 
-	public AltosImage get(AltosMapTile tile, AltosMapStore store, int width, int height) {
+	public AltosImage get(AltosMapTile tile) {
 		int		oldest = -1;
 		long		age = used;
 
@@ -148,7 +123,7 @@ public class AltosMapCache implements AltosMapCacheListener {
 					oldest = i;
 					break;
 				}
-				if (store.equals(element.store)) {
+				if (tile.store.equals(element.tile.store)) {
 					element.used = used++;
 					return element.image;
 				}
@@ -158,24 +133,15 @@ public class AltosMapCache implements AltosMapCacheListener {
 				}
 			}
 
-			try {
-				element = new MapCacheElement(tile, store);
-				element.used = used++;
-				if (elements[oldest] != null)
-					elements[oldest].flush();
+			element = new MapCacheElement(tile);
+			element.used = used++;
+			if (elements[oldest] != null)
+				elements[oldest].flush();
 
-				elements[oldest] = element;
-
-				if (element.image == null)
-					tile.set_status(AltosMapTile.loading);
-				else
-					tile.set_status(AltosMapTile.success);
-
-				return element.image;
-			} catch (IOException e) {
-				tile.set_status(AltosMapTile.failed);
-				return null;
-			}
+			elements[oldest] = element;
+			System.out.printf("AltosMapCache.get image ? %s\n",
+					  element.image == null ? "false" : "true");
+			return element.image;
 		}
 	}