Allow valid permutations of molecules in api

src/main/java/uk/ac/cam/cl/dtg/isaac/dos/IsaacSymbolicChemistryQuestion.java

@@ -31,6 +31,7 @@
 public class IsaacSymbolicChemistryQuestion extends IsaacSymbolicQuestion {
     @JsonProperty("isNuclear")
     private boolean isNuclear;
+    private boolean allowPermutations;
 
     /**
      * @return whether the question is a nuclear question or not
@@ -45,4 +46,16 @@ public boolean isNuclear() {
     public void setNuclear(boolean nuclear) {
         isNuclear = nuclear;
     }
+
+    /**
+     * @return whether the question allows compound permutations e.g. C10H22 == CH3(CH2)8CH3
+     */
+    public boolean getAllowPermutations() { return allowPermutations; }
+
+    /**
+     * @param allowPermutations set whether the question allows compound permutations e.g. C10H22 == CH3(CH2)8CH3
+     */
+    public void setAllowPermutations(boolean allowPermutations) {
+        this.allowPermutations = allowPermutations;
+    }
 }

src/main/java/uk/ac/cam/cl/dtg/isaac/dto/IsaacSymbolicChemistryQuestionDTO.java

@@ -25,6 +25,7 @@
 public class IsaacSymbolicChemistryQuestionDTO extends IsaacSymbolicQuestionDTO {
     @JsonProperty("isNuclear")
     private boolean isNuclear;
+    private boolean allowPermutations;
 
     /**
      * @return whether the question is a nuclear question or not
@@ -39,4 +40,16 @@ public boolean isNuclear() {
     public void setNuclear(boolean nuclear) {
         isNuclear = nuclear;
     }
+
+    /**
+     * @return whether the question allows compound permutations e.g. C10H22 == CH3(CH2)8CH3
+     */
+    public boolean getAllowPermutations() { return allowPermutations; }
+
+    /**
+     * @param allowPermutations set whether the question allows compound permutations e.g. C10H22 == CH3(CH2)8CH3
+     */
+    public void setAllowPermutations(boolean allowPermutations) {
+        this.allowPermutations = allowPermutations;
+    }
 }

src/main/java/uk/ac/cam/cl/dtg/isaac/quiz/IsaacSymbolicChemistryValidator.java

@@ -191,6 +191,8 @@ public QuestionValidationResponse validateQuestionResponse(final Question questi
                     req.put("target", formulaChoice.getMhchemExpression());
                     req.put("test", submittedFormula.getMhchemExpression());
                     req.put("description", chemistryQuestion.getId());
+                    req.put("allowPermutations", String.valueOf(chemistryQuestion.getAllowPermutations()));
+                    req.put("questionID", question.getId());
 
                     if (chemistryQuestion.isNuclear()) {
                         response = getResponseFromExternalValidator(nuclearValidatorUrl, req);
@@ -362,26 +364,36 @@ public QuestionValidationResponse validateQuestionResponse(final Question questi
                 // Input is nuclear, but atomic/mass numbers are invalid.
                 feedback = new Content("Check your atomic/mass numbers!");
 
-            } else if (closestMatch != null && closestMatch.isCorrect()) {
+            } else if (closestMatch != null && closestMatch.isCorrect() && closestResponse != null) {
 
                 // Weak match to a correct answer.
+                // closestResponse contains flags for generic mistakes from the Chemistry Checker.
+                // If any of these flags are false, provide feedback on the matched mistake.
 
-                if (!((String) closestResponse.get("expectedType")).contains("nuclear")
-                        && closestResponse.get("sameState").equals(false)) {
+                if (closestResponse.get("sameElements").equals(false)) {
 
-                    // Wrong state symbols
-                    feedback = new Content("Check your state symbols!");
+                    // Wrong element/compound
+                    feedback = new Content("Check your elements!");
 
                 } else if (closestResponse.get("sameCoefficient").equals(false)) {
 
                     // Wrong coefficients
                     feedback = new Content("Check your coefficients!");
 
+                } else if (!isNuclear && closestResponse.get("sameState").equals(false)) {
+
+                    // Wrong state symbols
+                    feedback = new Content("Check your state symbols!");
+
                 } else if (!isNuclear && closestResponse.get("sameArrow").equals(false)) {
 
                     // Wrong arrow
                     feedback = new Content("What type of reaction is this?");
 
+                } else if (!isNuclear && closestResponse.get("sameBrackets").equals(false)) {
+
+                    // Wrong brackets
+                    feedback = new Content("Check your brackets!");
                 }
             }
         }