feat: Basic structure view

grammars/TypeSpec.bnf

@@ -13,6 +13,7 @@
   psiImplClassSuffix='Impl'
   psiPackage='jp.s6n.idea.typespec.lang.psi'
   psiImplPackage='jp.s6n.idea.typespec.lang.psi.impl'
+  psiImplUtilClass='jp.s6n.idea.typespec.lang.psi.impl.TypeSpecImplUtil'
 
   tokens=[
     IMPORT          = 'import'
@@ -73,19 +74,28 @@ UsingStatement ::= USING Path SEMICOLON {extends=Statement}
 
 NamespaceStatement ::= Decorator* NAMESPACE Path (SEMICOLON | LBRACE Statement* RBRACE) {extends=Statement}
 
-EnumStatement ::= Decorator* ENUM Identifier EnumVariantsBlock {extends=Statement}
+EnumStatement ::= Decorator* ENUM Identifier EnumVariantsBlock {
+    extends=Statement
+    methods=[getPresentation]
+}
 
 EnumVariantsBlock ::= LBRACE [EnumVariant (COMMA EnumVariant)* COMMA?] RBRACE
 
 EnumVariant ::= Decorator* Identifier
 
-UnionStatement ::= Decorator* UNION Identifier UnionVariantsBlock {extends=Statement}
+UnionStatement ::= Decorator* UNION Identifier UnionVariantsBlock {
+    extends=Statement
+    methods=[getPresentation]
+}
 
 UnionVariantsBlock ::= LBRACE [UnionVariant (COMMA UnionVariant)* COMMA?] RBRACE
 
 UnionVariant ::= Decorator* Identifier COLON PathType
 
-ModelStatement ::= Decorator* MODEL Identifier (ModelExtends | ModelIs)? ModelPropertiesBlock {extends=Statement}
+ModelStatement ::= Decorator* MODEL Identifier (ModelExtends | ModelIs)? ModelPropertiesBlock {
+    extends=Statement
+    methods=[getPresentation]
+}
 
 ModelExtends ::= EXTENDS PathType
 
@@ -95,15 +105,24 @@ ModelPropertiesBlock ::= LBRACE ModelProperty* RBRACE
 
 ModelProperty ::= Decorator* Identifier QUEST? COLON Type SEMICOLON
 
-InterfaceStatement ::= Decorator* INTERFACE Identifier InterfaceOperationsBlock {extends=Statement}
+InterfaceStatement ::= Decorator* INTERFACE Identifier InterfaceOperationsBlock {
+    extends=Statement
+    methods=[getPresentation]
+}
 
 InterfaceOperationsBlock ::= LBRACE InterfaceOperation* RBRACE
 
 InterfaceOperation ::= Decorator* Operation SEMICOLON
 
-OperationStatement ::= Decorator* OP Operation SEMICOLON {extends=Statement}
+OperationStatement ::= Decorator* OP Operation SEMICOLON {
+    extends=Statement
+    methods=[getPresentation]
+}
 
-AliasStatement ::= ALIAS Identifier EQ Type SEMICOLON {extends=Statement}
+AliasStatement ::= ALIAS Identifier EQ Type SEMICOLON {
+    extends=Statement
+    methods=[getPresentation]
+}
 
 Operation ::= Identifier OperationArgumentList COLON Type
 

src/main/kotlin/jp/s6n/idea/typespec/lang/TypeSpecIconProvider.kt

@@ -0,0 +1,21 @@
+package jp.s6n.idea.typespec.lang
+
+import com.intellij.icons.AllIcons
+import com.intellij.ide.IconProvider
+import com.intellij.psi.PsiElement
+import jp.s6n.idea.typespec.lang.psi.*
+import javax.swing.Icon
+
+class TypeSpecIconProvider : IconProvider() {
+    override fun getIcon(element: PsiElement, flags: Int): Icon? {
+        return when (element) {
+            is TypeSpecEnumStatement -> AllIcons.Nodes.Enum
+            is TypeSpecUnionStatement -> AllIcons.Nodes.Enum
+            is TypeSpecModelStatement -> AllIcons.Nodes.Class
+            is TypeSpecInterfaceStatement -> AllIcons.Nodes.Interface
+            is TypeSpecAliasStatement -> AllIcons.Nodes.Type
+            is TypeSpecOperationStatement -> AllIcons.Nodes.Function
+            else -> null
+        }
+    }
+}

src/main/kotlin/jp/s6n/idea/typespec/lang/TypeSpecStructureViewFactory.kt

@@ -0,0 +1,41 @@
+package jp.s6n.idea.typespec.lang
+
+import com.intellij.ide.projectView.PresentationData
+import com.intellij.ide.structureView.StructureViewBuilder
+import com.intellij.ide.structureView.StructureViewModelBase
+import com.intellij.ide.structureView.StructureViewTreeElement
+import com.intellij.ide.structureView.TreeBasedStructureViewBuilder
+import com.intellij.ide.util.treeView.smartTree.TreeElement
+import com.intellij.lang.PsiStructureViewFactory
+import com.intellij.navigation.ItemPresentation
+import com.intellij.openapi.editor.Editor
+import com.intellij.psi.NavigatablePsiElement
+import com.intellij.psi.PsiFile
+import jp.s6n.idea.typespec.lang.psi.TypeSpecFile
+
+class TypeSpecStructureViewFactory : PsiStructureViewFactory {
+    override fun getStructureViewBuilder(file: PsiFile) = object : TreeBasedStructureViewBuilder() {
+        override fun createStructureViewModel(editor: Editor?) =  TypeSpecStructureViewModel(file, editor)
+    }
+}
+
+class TypeSpecStructureViewModel(file: PsiFile, editor: Editor?) : StructureViewModelBase(file, editor, TypeSpecStructureViewElement(file))
+
+class TypeSpecStructureViewElement(private val element: NavigatablePsiElement) : StructureViewTreeElement {
+    override fun getValue() = element
+
+    override fun getPresentation(): ItemPresentation = element.presentation ?: PresentationData()
+
+    override fun getChildren(): Array<TreeElement> {
+        return when (element) {
+            is TypeSpecFile -> {
+                element.statements
+                    .filterIsInstance<NavigatablePsiElement>()
+                    .filter { it.presentation != null }
+                    .map { TypeSpecStructureViewElement(it) }
+                    .toTypedArray()
+            }
+            else -> TreeElement.EMPTY_ARRAY
+        }
+    }
+}

src/main/kotlin/jp/s6n/idea/typespec/lang/psi/TypeSpecFile.kt

@@ -2,9 +2,12 @@ package jp.s6n.idea.typespec.lang.psi
 
 import com.intellij.extapi.psi.PsiFileBase
 import com.intellij.psi.FileViewProvider
+import com.intellij.psi.util.childrenOfType
 import jp.s6n.idea.typespec.lang.TypeSpecFileType
 import jp.s6n.idea.typespec.lang.TypeSpecLanguage
 
 class TypeSpecFile(viewProvider: FileViewProvider) : PsiFileBase(viewProvider, TypeSpecLanguage) {
+    val statements get() = childrenOfType<TypeSpecStatement>()
+
     override fun getFileType() = TypeSpecFileType
 }

src/main/kotlin/jp/s6n/idea/typespec/lang/psi/impl/TypeSpecImplUtil.kt

@@ -0,0 +1,43 @@
+package jp.s6n.idea.typespec.lang.psi.impl
+
+import com.intellij.navigation.ItemPresentation
+import jp.s6n.idea.typespec.lang.psi.TypeSpecAliasStatement
+import jp.s6n.idea.typespec.lang.psi.TypeSpecElement
+import jp.s6n.idea.typespec.lang.psi.TypeSpecEnumStatement
+import jp.s6n.idea.typespec.lang.psi.TypeSpecInterfaceStatement
+import jp.s6n.idea.typespec.lang.psi.TypeSpecModelStatement
+import jp.s6n.idea.typespec.lang.psi.TypeSpecOperationStatement
+import jp.s6n.idea.typespec.lang.psi.TypeSpecUnionStatement
+
+object TypeSpecImplUtil {
+    @JvmStatic
+    fun getPresentation(element: TypeSpecElement): ItemPresentation? {
+        return when (element) {
+            is TypeSpecEnumStatement -> object : ItemPresentation {
+                override fun getPresentableText() = element.identifier.text
+                override fun getIcon(unused: Boolean) = element.getIcon(0)
+            }
+            is TypeSpecUnionStatement -> object : ItemPresentation {
+                override fun getPresentableText() = element.identifier.text
+                override fun getIcon(unused: Boolean) = element.getIcon(0)
+            }
+            is TypeSpecModelStatement -> object : ItemPresentation {
+                override fun getPresentableText() = element.identifier.text
+                override fun getIcon(unused: Boolean) = element.getIcon(0)
+            }
+            is TypeSpecInterfaceStatement -> object : ItemPresentation {
+                override fun getPresentableText() = element.identifier.text
+                override fun getIcon(unused: Boolean) = element.getIcon(0)
+            }
+            is TypeSpecOperationStatement -> object : ItemPresentation {
+                override fun getPresentableText() = element.operation.identifier.text
+                override fun getIcon(unused: Boolean) = element.getIcon(0)
+            }
+            is TypeSpecAliasStatement -> object : ItemPresentation {
+                override fun getPresentableText() = element.identifier.text
+                override fun getIcon(unused: Boolean) = element.getIcon(0)
+            }
+            else -> null
+        }
+    }
+}