Assignment Details Part 4 of 7: FlagEvaluator computes details

src/main/java/cloud/eppo/BaseEppoClient.java

@@ -223,9 +223,18 @@ protected EppoValue getTypedAssignment(
       return defaultValue;
     }
 
+    // Evaluate flag with details
     FlagEvaluationResult evaluationResult =
         FlagEvaluator.evaluateFlag(
-            flag, flagKey, subjectKey, subjectAttributes, config.isConfigObfuscated());
+            flag,
+            flagKey,
+            subjectKey,
+            subjectAttributes,
+            config.isConfigObfuscated(),
+            config.getEnvironmentName(),
+            config.getConfigFetchedAt(),
+            config.getConfigPublishedAt());
+
     EppoValue assignedValue =
         evaluationResult.getVariation() != null ? evaluationResult.getVariation().getValue() : null;
 

src/main/java/cloud/eppo/FlagEvaluationResult.java

@@ -1,10 +1,12 @@
 package cloud.eppo;
 
-import cloud.eppo.api.Attributes;
+import cloud.eppo.api.*;
 import cloud.eppo.ufc.dto.Variation;
+import java.util.Date;
 import java.util.Map;
 import java.util.Objects;
 
+/** Flag evaluation result that includes detailed evaluation information. */
 public class FlagEvaluationResult {
 
   private final String flagKey;
@@ -14,6 +16,7 @@ public class FlagEvaluationResult {
   private final Variation variation;
   private final Map<String, String> extraLogging;
   private final boolean doLog;
+  private final EvaluationDetails evaluationDetails;
 
   public FlagEvaluationResult(
       String flagKey,
@@ -22,45 +25,68 @@ public FlagEvaluationResult(
       String allocationKey,
       Variation variation,
       Map<String, String> extraLogging,
-      boolean doLog) {
+      boolean doLog,
+      EvaluationDetails evaluationDetails) {
     this.flagKey = flagKey;
     this.subjectKey = subjectKey;
     this.subjectAttributes = subjectAttributes;
     this.allocationKey = allocationKey;
     this.variation = variation;
     this.extraLogging = extraLogging;
     this.doLog = doLog;
+    this.evaluationDetails = evaluationDetails;
   }
 
   @Override
   public String toString() {
-    return "FlagEvaluationResult{" +
-      "flagKey='" + flagKey + '\'' +
-      ", subjectKey='" + subjectKey + '\'' +
-      ", subjectAttributes=" + subjectAttributes +
-      ", allocationKey='" + allocationKey + '\'' +
-      ", variation=" + variation +
-      ", extraLogging=" + extraLogging +
-      ", doLog=" + doLog +
-      '}';
+    return "FlagEvaluationResult{"
+        + "flagKey='"
+        + flagKey
+        + '\''
+        + ", subjectKey='"
+        + subjectKey
+        + '\''
+        + ", subjectAttributes="
+        + subjectAttributes
+        + ", allocationKey='"
+        + allocationKey
+        + '\''
+        + ", variation="
+        + variation
+        + ", extraLogging="
+        + extraLogging
+        + ", doLog="
+        + doLog
+        + ", evaluationDetails="
+        + evaluationDetails
+        + '}';
   }
 
   @Override
   public boolean equals(Object o) {
     if (o == null || getClass() != o.getClass()) return false;
     FlagEvaluationResult that = (FlagEvaluationResult) o;
     return doLog == that.doLog
-            && Objects.equals(flagKey, that.flagKey)
-            && Objects.equals(subjectKey, that.subjectKey)
-            && Objects.equals(subjectAttributes, that.subjectAttributes)
-            && Objects.equals(allocationKey, that.allocationKey)
-            && Objects.equals(variation, that.variation)
-            && Objects.equals(extraLogging, that.extraLogging);
+        && Objects.equals(flagKey, that.flagKey)
+        && Objects.equals(subjectKey, that.subjectKey)
+        && Objects.equals(subjectAttributes, that.subjectAttributes)
+        && Objects.equals(allocationKey, that.allocationKey)
+        && Objects.equals(variation, that.variation)
+        && Objects.equals(extraLogging, that.extraLogging)
+        && Objects.equals(evaluationDetails, that.evaluationDetails);
   }
 
   @Override
   public int hashCode() {
-    return Objects.hash(flagKey, subjectKey, subjectAttributes, allocationKey, variation, extraLogging, doLog);
+    return Objects.hash(
+        flagKey,
+        subjectKey,
+        subjectAttributes,
+        allocationKey,
+        variation,
+        extraLogging,
+        doLog,
+        evaluationDetails);
   }
 
   public String getFlagKey() {
@@ -90,4 +116,130 @@ public Map<String, String> getExtraLogging() {
   public boolean doLog() {
     return doLog;
   }
+
+  public EvaluationDetails getEvaluationDetails() {
+    return evaluationDetails;
+  }
+
+  /** Builder to construct flag evaluation results during flag evaluation. */
+  public static class Builder {
+    private String flagKey;
+    private String subjectKey;
+    private Attributes subjectAttributes;
+    private String allocationKey;
+    private Variation variation;
+    private Map<String, String> extraLogging;
+    private boolean doLog;
+
+    // Delegate to EvaluationDetails.Builder for evaluation details
+    private final EvaluationDetails.Builder detailsBuilder = EvaluationDetails.builder();
+
+    public Builder flagKey(String flagKey) {
+      this.flagKey = flagKey;
+      return this;
+    }
+
+    public Builder subjectKey(String subjectKey) {
+      this.subjectKey = subjectKey;
+      return this;
+    }
+
+    public Builder subjectAttributes(Attributes subjectAttributes) {
+      this.subjectAttributes = subjectAttributes;
+      return this;
+    }
+
+    public Builder allocationKey(String allocationKey) {
+      this.allocationKey = allocationKey;
+      return this;
+    }
+
+    public Builder variation(Variation variation) {
+      this.variation = variation;
+      return this;
+    }
+
+    public Builder extraLogging(Map<String, String> extraLogging) {
+      this.extraLogging = extraLogging;
+      return this;
+    }
+
+    public Builder doLog(boolean doLog) {
+      this.doLog = doLog;
+      return this;
+    }
+
+    public Builder environmentName(String environmentName) {
+      detailsBuilder.environmentName(environmentName);
+      return this;
+    }
+
+    public Builder flagEvaluationCode(FlagEvaluationCode code) {
+      detailsBuilder.flagEvaluationCode(code);
+      return this;
+    }
+
+    public Builder flagEvaluationDescription(String description) {
+      detailsBuilder.flagEvaluationDescription(description);
+      return this;
+    }
+
+    public Builder banditKey(String banditKey) {
+      detailsBuilder.banditKey(banditKey);
+      return this;
+    }
+
+    public Builder banditAction(String banditAction) {
+      detailsBuilder.banditAction(banditAction);
+      return this;
+    }
+
+    public Builder matchedRule(MatchedRule matchedRule) {
+      detailsBuilder.matchedRule(matchedRule);
+      return this;
+    }
+
+    public Builder matchedAllocation(AllocationDetails matchedAllocation) {
+      detailsBuilder.matchedAllocation(matchedAllocation);
+      return this;
+    }
+
+    public Builder addUnmatchedAllocation(AllocationDetails allocation) {
+      detailsBuilder.addUnmatchedAllocation(allocation);
+      return this;
+    }
+
+    public Builder addUnevaluatedAllocation(AllocationDetails allocation) {
+      detailsBuilder.addUnevaluatedAllocation(allocation);
+      return this;
+    }
+
+    public Builder configFetchedAt(Date configFetchedAt) {
+      detailsBuilder.configFetchedAt(configFetchedAt);
+      return this;
+    }
+
+    public Builder configPublishedAt(Date configPublishedAt) {
+      detailsBuilder.configPublishedAt(configPublishedAt);
+      return this;
+    }
+
+    public FlagEvaluationResult build() {
+      // Set variation details before building
+      if (variation != null) {
+        detailsBuilder.variationKey(variation.getKey());
+        detailsBuilder.variationValue(variation.getValue());
+      }
+
+      return new FlagEvaluationResult(
+          flagKey,
+          subjectKey,
+          subjectAttributes,
+          allocationKey,
+          variation,
+          extraLogging,
+          doLog,
+          detailsBuilder.build());
+    }
+  }
 }