[Analysis API] introduce some basic API to create KtSymbol by Java PSI

^KT-50240

analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/LLFirResolveSessionDepended.kt

@@ -13,6 +13,7 @@ import org.jetbrains.kotlin.analysis.low.level.api.fir.api.LLFirResolveSession
 import org.jetbrains.kotlin.analysis.low.level.api.fir.element.builder.FirElementBuilder
 import org.jetbrains.kotlin.analysis.low.level.api.fir.element.builder.FirTowerContextProvider
 import org.jetbrains.kotlin.analysis.low.level.api.fir.file.structure.KtToFirMapping
+import org.jetbrains.kotlin.analysis.low.level.api.fir.sessions.LLFirSession
 import org.jetbrains.kotlin.analysis.low.level.api.fir.state.LLFirResolvableResolveSession
 import org.jetbrains.kotlin.analysis.low.level.api.fir.state.TowerProviderForElementForState
 import org.jetbrains.kotlin.analysis.low.level.api.fir.util.LLFirScopeSessionProvider
@@ -54,7 +55,7 @@ internal class LLFirResolveSessionDepended(
             .getScopeSession()
     }
 
-    override fun getSessionFor(module: KtModule): FirSession =
+    override fun getSessionFor(module: KtModule): LLFirSession =
         originalFirResolveSession.getSessionFor(module)
 
     override fun getOrBuildFirFor(element: KtElement): FirElement? {

analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/api/LLFirResolveSession.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.analysis.low.level.api.fir.api
 
 import com.intellij.openapi.project.Project
 import org.jetbrains.kotlin.analysis.low.level.api.fir.element.builder.FirTowerContextProvider
+import org.jetbrains.kotlin.analysis.low.level.api.fir.sessions.LLFirSession
 import org.jetbrains.kotlin.analysis.project.structure.KtModule
 import org.jetbrains.kotlin.diagnostics.KtPsiDiagnostic
 import org.jetbrains.kotlin.fir.FirElement
@@ -30,7 +31,7 @@ abstract class LLFirResolveSession {
 
     abstract val useSiteKtModule: KtModule
 
-    internal abstract fun getSessionFor(module: KtModule): FirSession
+    abstract fun getSessionFor(module: KtModule): LLFirSession
 
     abstract fun getScopeSessionFor(firSession: FirSession): ScopeSession
 

analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/project/structure/LLFirLibrarySessionFactory.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.analysis.low.level.api.fir.project.structure
 
 import com.intellij.openapi.project.Project
+import org.jetbrains.kotlin.analysis.low.level.api.fir.providers.LLFirFirClassByPsiClassProvider
 import org.jetbrains.kotlin.analysis.low.level.api.fir.providers.LLFirLibrarySessionProvider
 import org.jetbrains.kotlin.analysis.low.level.api.fir.sessions.LLFirLibraryLikeSession
 import org.jetbrains.kotlin.analysis.low.level.api.fir.sessions.LLFirLibrarySession
@@ -77,6 +78,7 @@ internal class LLFirLibrarySessionFactory(
                 add(builtinsSession.symbolProvider)
             }
 
+            register(LLFirFirClassByPsiClassProvider::class, LLFirFirClassByPsiClassProvider(this))
             register(FirProvider::class, LLFirLibrarySessionProvider(symbolProvider))
             register(FirSymbolProvider::class, symbolProvider)
             register(FirJvmTypeMapper::class, FirJvmTypeMapper(this))

analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/providers/LLFirFirClassByPsiClassProvider.kt

@@ -0,0 +1,64 @@
+/*
+ * Copyright 2010-2022 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.analysis.low.level.api.fir.providers
+
+import com.intellij.psi.PsiClass
+import com.intellij.psi.PsiJavaFile
+import com.intellij.psi.PsiTypeParameter
+import org.jetbrains.kotlin.analysis.low.level.api.fir.sessions.LLFirSession
+import org.jetbrains.kotlin.asJava.KtLightClassMarker
+import org.jetbrains.kotlin.fir.FirSession
+import org.jetbrains.kotlin.fir.FirSessionComponent
+import org.jetbrains.kotlin.fir.java.JavaSymbolProvider
+import org.jetbrains.kotlin.fir.psi
+import org.jetbrains.kotlin.fir.resolve.providers.symbolProvider
+import org.jetbrains.kotlin.fir.symbols.impl.FirRegularClassSymbol
+import org.jetbrains.kotlin.name.ClassId
+import org.jetbrains.kotlin.name.FqName
+
+class LLFirFirClassByPsiClassProvider(private val session: LLFirSession) : FirSessionComponent {
+    fun getFirClass(psiClass: PsiClass): FirRegularClassSymbol? {
+        require(psiClass !is PsiTypeParameter) {
+            "${LLFirFirClassByPsiClassProvider::class.simpleName} can create only regular classes"
+        }
+
+        require(psiClass !is KtLightClassMarker) {
+            "${LLFirFirClassByPsiClassProvider::class.simpleName} can create only non-kotlin classes"
+        }
+
+        if (psiClass.qualifiedName == null) {
+            return null // not yet supported
+        }
+
+        val firClassSymbol = createFirClassFromFirProvider(psiClass)
+        check(firClassSymbol.fir.psi == psiClass)
+        return firClassSymbol
+    }
+
+    private fun createFirClassFromFirProvider(psiClass: PsiClass): FirRegularClassSymbol {
+        val classId = psiClass.classIdIfNonLocal
+            ?: error("No classId for non-local class")
+        val provider = session.nullableJavaSymbolProvider ?: session.symbolProvider
+        val symbol = (provider.getClassLikeSymbolByClassId(classId)
+            ?: error("No classifier found with $classId"))
+        return symbol as FirRegularClassSymbol
+    }
+}
+
+private val FirSession.nullableJavaSymbolProvider: JavaSymbolProvider? by FirSession.nullableSessionComponentAccessor()
+
+
+val LLFirSession.firClassByPsiClassProvider: LLFirFirClassByPsiClassProvider by FirSession.sessionComponentAccessor()
+
+private val PsiClass.classIdIfNonLocal: ClassId?
+    get() {
+        val packageName = (containingFile as? PsiJavaFile)?.packageName ?: return null
+        val packageFqName = FqName(packageName)
+
+        val classesNames = generateSequence(this) { it.containingClass }.map { it.name }.toList().asReversed()
+        if (classesNames.any { it == null }) return null
+        return ClassId(packageFqName, FqName(classesNames.joinToString(separator = ".")), false)
+    }

analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionFactory.kt

@@ -150,6 +150,7 @@ internal object LLFirSessionFactory {
 
             register(FirDependenciesSymbolProvider::class, dependencyProvider)
             register(FirJvmTypeMapper::class, FirJvmTypeMapper(this))
+            register(LLFirFirClassByPsiClassProvider::class, LLFirFirClassByPsiClassProvider(this))
 
             configureSession?.invoke(this)
             extensionService.additionalCheckers.forEach(session.checkersComponent::register)

analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/state/LLFirResolvableResolveSession.kt

@@ -40,8 +40,8 @@ internal abstract class LLFirResolvableResolveSession(
 
     final override val useSiteFirSession = sessionProvider.rootModuleSession
 
-    override fun getSessionFor(module: KtModule): FirSession =
-        sessionProvider.getResolvableSession(module)
+    override fun getSessionFor(module: KtModule): LLFirSession =
+        sessionProvider.getSession(module)
 
     override fun getScopeSessionFor(firSession: FirSession): ScopeSession {
         requireIsInstance<LLFirSession>(firSession)