From c019a029ec724b80e71278a6291f407d1862bcf1 Mon Sep 17 00:00:00 2001
From: Viktor Lofgren <vlofgren@marginalia.nu>
Date: Thu, 17 Aug 2023 17:42:31 +0200
Subject: [PATCH] (flags) Documentation and preventative bugfix

---
 .../java/nu/marginalia/model/idx/DocumentFlags.java |  2 +-
 .../nu/marginalia/model/idx/DocumentMetadata.java   | 13 ++++++++++++-
 .../java/nu/marginalia/model/idx/WordMetadata.java  |  5 +++++
 3 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/code/common/model/src/main/java/nu/marginalia/model/idx/DocumentFlags.java b/code/common/model/src/main/java/nu/marginalia/model/idx/DocumentFlags.java
index 7ed409c1..0c051341 100644
--- a/code/common/model/src/main/java/nu/marginalia/model/idx/DocumentFlags.java
+++ b/code/common/model/src/main/java/nu/marginalia/model/idx/DocumentFlags.java
@@ -25,7 +25,7 @@ public enum DocumentFlags {
         EnumSet<DocumentFlags> ret = EnumSet.noneOf(DocumentFlags.class);
 
         for (DocumentFlags f : values()) {
-            if ((encodedValue & f.asBit()) > 0) {
+            if ((encodedValue & f.asBit() & 0xff) > 0) {
                 ret.add(f);
             }
         }
diff --git a/code/common/model/src/main/java/nu/marginalia/model/idx/DocumentMetadata.java b/code/common/model/src/main/java/nu/marginalia/model/idx/DocumentMetadata.java
index 0b1fe480..f9853ab2 100644
--- a/code/common/model/src/main/java/nu/marginalia/model/idx/DocumentMetadata.java
+++ b/code/common/model/src/main/java/nu/marginalia/model/idx/DocumentMetadata.java
@@ -9,6 +9,17 @@ import java.util.Set;
 import static java.lang.Math.max;
 import static java.lang.Math.min;
 
+/**  Document level metadata designed to fit in a single 64 bit long.
+ *
+ * @param avgSentLength average sentence length
+ * @param rank domain ranking
+ * @param encDomainSize encoded number of documents in the domain
+ * @param topology a measure of how important the document is
+ * @param year encoded publishing year
+ * @param sets bit mask for search sets
+ * @param quality quality of the document
+ * @param flags flags (see {@link DocumentFlags})
+ */
 public record DocumentMetadata(int avgSentLength,
                                int rank,
                                int encDomainSize,
@@ -98,7 +109,7 @@ public record DocumentMetadata(int avgSentLength,
     }
 
     public static boolean hasFlags(long encoded, long metadataBitMask) {
-        return (encoded & metadataBitMask) == metadataBitMask;
+        return ((encoded & 0xFF) & metadataBitMask) == metadataBitMask;
     }
 
     public long encode() {
diff --git a/code/common/model/src/main/java/nu/marginalia/model/idx/WordMetadata.java b/code/common/model/src/main/java/nu/marginalia/model/idx/WordMetadata.java
index dfb77b8a..5096c44f 100644
--- a/code/common/model/src/main/java/nu/marginalia/model/idx/WordMetadata.java
+++ b/code/common/model/src/main/java/nu/marginalia/model/idx/WordMetadata.java
@@ -6,6 +6,11 @@ import nu.marginalia.bbpc.BrailleBlockPunchCards;
 import java.util.EnumSet;
 import java.util.Set;
 
+/** Word level metadata designed to fit in a single 64 bit long.
+ *
+ * @param positions bitmask of term positions within the document
+ * @param flags word flags (see {@link WordFlags})
+ */
 public record WordMetadata(long positions,
                            byte flags) {