provide incomplete completion for "form_theme"

src/main/java/fr/adrienbrault/idea/symfony2plugin/templating/TwigTemplateCompletionContributor.java

@@ -538,6 +538,13 @@ public void addCompletions(@NotNull CompletionParameters parameters, ProcessingC
             TwigPattern.getCompletablePattern(),
             new IncompleteFormPrintBlockCompletionProvider()
         );
+
+        // {{ form_theme => "form_theme form 'TEMPLATE'"
+        extend(
+            CompletionType.BASIC,
+            PlatformPatterns.psiElement(TwigTokenTypes.TAG_NAME),
+            new IncompleteFormThemeTemplateCompletionProvider()
+        );
     }
 
     private boolean isCompletionStartingMatch(@NotNull String fullText, @NotNull CompletionParameters completionParameters, int minLength) {
@@ -1072,6 +1079,66 @@ public boolean accepts(@NotNull String s, ProcessingContext processingContext) {
         }
     }
 
+    private class IncompleteFormThemeTemplateCompletionProvider extends CompletionProvider<CompletionParameters> {
+        @Override
+        protected void addCompletions(@NotNull CompletionParameters completionParameters, @NotNull ProcessingContext processingContext, @NotNull CompletionResultSet resultSet) {
+            PsiElement originalPosition = completionParameters.getOriginalPosition();
+            if (originalPosition == null) {
+                return;
+            }
+
+            if(!Symfony2ProjectComponent.isEnabled(originalPosition)) {
+                return;
+            }
+
+            resultSet.restartCompletionOnPrefixChange(StandardPatterns.string().longerThan(1).with(new PatternCondition<>("include startsWith") {
+                @Override
+                public boolean accepts(@NotNull String s, ProcessingContext processingContext) {
+                    return "form_theme".startsWith(s);
+                }
+            }));
+
+            if (!isCompletionStartingMatch("form_theme", completionParameters, 3)) {
+                return;
+            }
+
+            List<String> orderedList = null;
+
+            Project project = completionParameters.getPosition().getProject();
+            for (Map.Entry<String, PsiVariable> entry : TwigTypeResolveUtil.collectScopeVariables(originalPosition).entrySet()) {
+                PhpType phpType = PhpIndex.getInstance(project).completeType(project, PhpType.from(entry.getValue().getTypes().toArray(new String[0])), new HashSet<>());
+                if (!FormFieldResolver.isFormView(phpType)) {
+                    continue;
+                }
+
+                PsiElement element = entry.getValue().getElement();
+                if (element == null)  {
+                    continue;
+                }
+
+                String typeText = null;
+                Collection<PhpClass> formTypeFromFormFactory = FormFieldResolver.getFormTypeFromFormFactory(element);
+                if (formTypeFromFormFactory.size() > 0) {
+                    typeText = StringUtils.stripStart(formTypeFromFormFactory.iterator().next().getFQN(), "\\");
+                }
+
+                if (orderedList == null) {
+                    orderedList = TwigUtil.getFormThemeTemplateUsageAsOrderedList(completionParameters.getPosition().getProject());
+                }
+
+                CompletionSorter completionSorter = CompletionService.getCompletionService()
+                    .defaultSorter(completionParameters, resultSet.getPrefixMatcher())
+                    .weighBefore("priority", new ServiceCompletionProvider.MyLookupElementWeigher(orderedList));
+
+                resultSet = resultSet.withRelevanceSorter(completionSorter);
+
+                for (String s : orderedList) {
+                    resultSet.addElement(LookupElementBuilder.create(String.format("form_theme %s '%s'", entry.getKey(), s)).withTypeText(typeText).withIcon(TwigIcons.TwigFileIcon));
+                }
+            }
+        }
+    }
+
     /**
      * {% for => "for flash in app.flashes"
      */

src/main/java/fr/adrienbrault/idea/symfony2plugin/templating/util/TwigUtil.java

@@ -110,6 +110,8 @@ public enum NamespaceType {
     private static final Key<CachedValue<List<String>>> SYMFONY_TEMPLATE_EMBED_LIST = new Key<>("SYMFONY_TEMPLATE_EMBED_LIST");
     private static final Key<CachedValue<List<String>>> SYMFONY_TEMPLATE_EXTENDS_LIST = new Key<>("SYMFONY_TEMPLATE_EXTENDS_LIST");
 
+    private static final Key<CachedValue<List<String>>> SYMFONY_TEMPLATE_FORM_THEME_LIST = new Key<>("SYMFONY_TEMPLATE_FORM_THEME_LIST");
+
     private static final Key<CachedValue<Set<String>>> SYMFONY_NAMED_TOKEN_TAGS = new Key<>("SYMFONY_NAMED_TOKEN_TAGS");
     private static final Key<CachedValue<Map<String, String>>> SYMFONY_DEPRECATED_NAMED_TOKEN_TAGS = new Key<>("SYMFONY_DEPRECATED_NAMED_TOKEN_TAGS");
 
@@ -2898,6 +2900,55 @@ public static List<String> getIncludeTemplateUsageAsOrderedList(@NotNull Project
         }, false);
     }
 
+    public static List<String> getFormThemeTemplateUsageAsOrderedList(@NotNull Project project) {
+        return CachedValuesManager.getManager(project).getCachedValue(project, SYMFONY_TEMPLATE_FORM_THEME_LIST, () -> {
+            Set<String> allKeys = FileBasedIndex.getInstance().getAllKeys(TwigIncludeStubIndex.KEY, project)
+                .stream()
+                .filter(s -> !s.toLowerCase().contains("@webprofiler") && !s.toLowerCase().contains("/profiler/") && !s.toLowerCase().contains("@twig"))
+                .collect(Collectors.toSet());
+
+            Map<String, Integer> usage = new HashMap<>();
+
+            // try to find core
+            for (Map.Entry<String, Set<VirtualFile>> entry : getTemplateMap(project, true).entrySet()) {
+                for (VirtualFile virtualFile : entry.getValue()) {
+                    String path = virtualFile.getPath().replace("\\", "/");
+                    if (path.contains("/twig-bridge/Resources/views/")) {
+                        int j = path.lastIndexOf("/");
+                        if (j > 0) {
+                            int i = path.lastIndexOf("/", j - 1);
+                            if (i > 0) {
+                                String output = path.substring(i + 1);
+                                if (output.startsWith("Form/")) {
+                                    usage.putIfAbsent(entry.getKey(), 0);
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+
+            for (String allKey : allKeys) {
+              List<fr.adrienbrault.idea.symfony2plugin.stubs.dict.TemplateInclude> values = FileBasedIndex.getInstance().getValues(TwigIncludeStubIndex.KEY, allKey, GlobalSearchScope.allScope(project));
+              for (fr.adrienbrault.idea.symfony2plugin.stubs.dict.TemplateInclude value : values) {
+                    if (value.getType() == TemplateInclude.TYPE.FORM_THEME) {
+                        usage.putIfAbsent(allKey, 0);
+                        usage.put(allKey, usage.get(allKey) + 1);
+                    }
+                }
+            }
+
+            List<String> collect = usage.entrySet()
+                .stream()
+                .sorted(Map.Entry.comparingByValue(Comparator.reverseOrder()))
+                .map(Map.Entry::getKey)
+                .limit(10)
+                .collect(Collectors.toList());
+
+            return CachedValueProvider.Result.create(collect, FileIndexCaches.getModificationTrackerForIndexId(project, TwigIncludeStubIndex.KEY));
+        }, false);
+    }
+
     public static List<String> getEmbedTemplateUsageAsOrderedList(@NotNull Project project) {
         return CachedValuesManager.getManager(project).getCachedValue(project, SYMFONY_TEMPLATE_EMBED_LIST, () -> {
             Set<String> allKeys = FileBasedIndex.getInstance().getAllKeys(TwigIncludeStubIndex.KEY, project)