Added code completion feature.

Author: dalgarins

build.gradle

@@ -4,7 +4,7 @@ plugins {
     id 'java'
     id 'org.jetbrains.intellij' version '0.6.5'
     id 'org.jetbrains.kotlin.jvm' version '1.4.10'
-    id "org.jetbrains.grammarkit" version "2020.2.1"
+    id "org.jetbrains.grammarkit" version "2020.3.2"
 }
 
 grammarKit {
@@ -13,7 +13,7 @@ grammarKit {
 }
 
 group 'co.anbora.labs'
-version '2.4.0-SNAPSHOT'
+version '2.5.0-SNAPSHOT'
 
 repositories {
     mavenCentral()
@@ -61,7 +61,7 @@ sourceSets {
 
 // See https://github.com/JetBrains/gradle-intellij-plugin/
 intellij {
-    version = 'LATEST-EAP-SNAPSHOT'
+    version = '2020.3.3'
 }
 
 tasks.withType(JavaCompile) { options.encoding = 'UTF-8' }
@@ -77,6 +77,12 @@ publishPlugin {
 patchPluginXml {
     changeNotes """
       <ul>
+          <li><b>2.5.0</b> <em>(2021-03-17)</em> - Added basic code completation</li>
+              <ul>
+                  <li>Added basic code completation </li>
+                  <li>Fixed issue with access index array </li>
+              </ul>
+          </li>
           <li><b>2.4.0</b> <em>(2021-02-14)</em> - Added code folding</li>
               <ul>
                   <li>Added code folding </li>

src/main/kotlin/co/anbora/labs/firebase/lang/core/FirebasePsiPatterns.kt

@@ -23,11 +23,11 @@ object FirebasePsiPatterns {
     fun serviceStatement(): PsiElementPattern.Capture<PsiElement> =
             psiElementWithParent<FirebaseRulesServiceDef>()
 
-    fun serviceBlock(): PsiElementPattern.Capture<PsiElement> =
-            psiElementWithParent<FirebaseRulesServiceBlock>()
+    fun pathStatement(): PsiElementPattern.Capture<PsiElement> =
+            psiElementWithParent<FirebaseRulesPathStatement>()
 
-    fun matchStatement(): PsiElementPattern.Capture<PsiElement> =
-            psiElementWithParent<FirebaseRulesMatchDef>()
+    fun permissionStatement(): PsiElementPattern.Capture<PsiElement> =
+            psiElementWithParent<FirebaseRulesPermissionStatement>()
 
     fun allowStatement(): PsiElementPattern.Capture<PsiElement> =
             psiElementWithParent<FirebaseRulesAllowStatement>()

src/main/kotlin/co/anbora/labs/firebase/lang/core/completion/FirebaseCompletionContributor.kt

@@ -1,6 +1,9 @@
 package co.anbora.labs.firebase.lang.core.completion
 
 import co.anbora.labs.firebase.lang.FirebaseRulesLanguage
+import co.anbora.labs.firebase.lang.core.FirebasePsiPatterns.pathStatement
+import co.anbora.labs.firebase.lang.core.FirebasePsiPatterns.permissionStatement
+import co.anbora.labs.firebase.lang.core.FirebasePsiPatterns.serviceStatement
 import com.intellij.codeInsight.completion.CompletionContributor
 import com.intellij.codeInsight.completion.CompletionType.BASIC
 import com.intellij.patterns.PlatformPatterns.psiElement
@@ -17,5 +20,20 @@ class FirebaseCompletionContributor: CompletionContributor() {
             psiElement().withLanguage(FirebaseRulesLanguage),
             FirebaseCompletionProvider()
         )
+        extend(
+            BASIC,
+            serviceStatement(),
+            KeywordCompletionProvider(*serviceNameCompletion)
+        )
+        extend(
+            BASIC,
+            pathStatement(),
+            KeywordCompletionProvider(*matchPathCompletion)
+        )
+        extend(
+            BASIC,
+            permissionStatement(),
+            KeywordCompletionProvider(*allowPermissionCompletion)
+        )
     }
 }

src/main/kotlin/co/anbora/labs/firebase/lang/core/completion/KeywordCompletionProvider.kt

@@ -0,0 +1,19 @@
+package co.anbora.labs.firebase.lang.core.completion
+
+import com.intellij.codeInsight.completion.CompletionParameters
+import com.intellij.codeInsight.completion.CompletionProvider
+import com.intellij.codeInsight.completion.CompletionResultSet
+import com.intellij.codeInsight.lookup.LookupElementBuilder
+import com.intellij.util.ProcessingContext
+
+class KeywordCompletionProvider(private vararg val keywords: String) : CompletionProvider<CompletionParameters>() {
+    override fun addCompletions(
+            parameters: CompletionParameters,
+            context: ProcessingContext,
+            result: CompletionResultSet
+    ) {
+        keywords.forEach { keyword ->
+            result.addElement(LookupElementBuilder.create(keyword))
+        }
+    }
+}

src/main/kotlin/co/anbora/labs/firebase/lang/core/psi/mixings/MatchDefMixing.kt

@@ -0,0 +1,6 @@
+package co.anbora.labs.firebase.lang.core.psi.mixings
+
+import com.intellij.psi.PsiNamedElement
+
+abstract class MatchDefMixing: PsiNamedElement {
+}