1 files changed, 63 insertions, 0 deletions
diff --git a/src/main/java/dev/dnpm/oshelper/atc/services/AgentCodeService.java b/src/main/java/dev/dnpm/oshelper/atc/services/AgentCodeService.java
index 5d215a7..16a03f7 100644
--- a/src/main/java/dev/dnpm/oshelper/atc/services/AgentCodeService.java
+++ b/src/main/java/dev/dnpm/oshelper/atc/services/AgentCodeService.java
@@ -26,8 +26,15 @@ package dev.dnpm.oshelper.atc.services;
 
 
 import dev.dnpm.oshelper.atc.AgentCode;
+import org.jspecify.annotations.NullMarked;
 
+import java.util.Comparator;
 import java.util.List;
+import java.util.Objects;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
+import static java.util.stream.Collectors.groupingBy;
 
 /**
  * Common interface for agent code services
@@ -38,6 +45,62 @@ import java.util.List;
 public interface AgentCodeService {
 
     /**
+     * Filters the provided list of AgentCodes to include only the latest available versions
+     * for each unique code name and, if required, code.
+     * If the input list is empty or null, an empty list will be returned.
+     *
+     * @param agentCodes A list of {@link AgentCode} objects to be filtered. Each object in the list
+     *                   should contain information about the agent's code, name, system, and version.
+     * @param classifier A function that returns a string value to be used as a key for grouping agent codes.
+     * @return A list of {@link AgentCode} objects representing the latest available versions of unique agent codes.
+     * If no valid inputs are provided, an empty list is returned.
+     */
+    @NullMarked
+    static List<AgentCode> latestAgentCodeVersions(List<AgentCode> agentCodes, Function<AgentCode, String> classifier) {
+        return latestAvailable(agentCodes, classifier);
+    }
+
+    /**
+     * Function that extracts the name of an {@link AgentCode} object.
+     * This function is used as a classifier for grouping agent codes by their name.
+     */
+    Function<AgentCode, String> byCodeOnly = AgentCode::getName;
+
+    /**
+     * Function that extracts the name and code of an {@link AgentCode} object.
+     * This function is used as a classifier for grouping agent codes by their name and code.
+     */
+    Function<AgentCode, String> byNameAndCode = (agentCode ->
+            String.format("%s_%s", agentCode.getCode(), agentCode.getName())
+    );
+
+
+    @NullMarked
+    private static List<AgentCode> latestAvailable(
+            List<AgentCode> agentCodes,
+            Function<AgentCode, String> classifier
+    ) {
+        return agentCodes.stream()
+                .collect(groupingBy(classifier)).values().stream()
+                .map(list ->
+                        list.stream()
+                                .sorted(Comparator.comparing(AgentCode::getCode))
+                                .max((ac1, ac2) -> {
+                                    if (null == ac1.getVersion()) {
+                                        return -1;
+                                    } else if (null == ac2.getVersion()) {
+                                        return 1;
+                                    }
+                                    return ac1.getVersion().compareTo(ac2.getVersion());
+                                })
+                                .orElse(null)
+                )
+                .filter(Objects::nonNull)
+                .distinct()
+                .collect(Collectors.toList());
+    }
+
+    /**
      * Queries source for agents with name and code starting with query string.
      * If size is zero, all available results will be returned.
      *