Fix .bazelproject file type recognition issue

plugin-bazel/src/main/kotlin/org/jetbrains/bazel/languages/projectview/ProjectViewService.kt

@@ -1,15 +1,22 @@
 package org.jetbrains.bazel.languages.projectview
 
 import com.google.common.hash.HashCode
+import com.intellij.openapi.application.ApplicationManager
 import com.intellij.openapi.application.readAction
 import com.intellij.openapi.components.Service
+import com.intellij.openapi.diagnostic.logger
+import com.intellij.openapi.fileTypes.FileTypeManager
+import com.intellij.openapi.progress.ProcessCanceledException
 import com.intellij.openapi.progress.runBlockingCancellable
 import com.intellij.openapi.project.Project
+import com.intellij.openapi.vfs.VirtualFile
 import com.intellij.openapi.vfs.VirtualFileManager
+import com.intellij.psi.PsiFile
 import com.intellij.psi.PsiFileFactory
 import com.intellij.psi.PsiManager
 import org.jetbrains.bazel.config.rootDir
 import org.jetbrains.bazel.flow.open.ProjectViewFileUtils
+import org.jetbrains.bazel.languages.projectview.base.ProjectViewFileType
 import org.jetbrains.bazel.languages.projectview.base.ProjectViewLanguage
 import org.jetbrains.bazel.languages.projectview.psi.ProjectViewPsiFile
 import org.jetbrains.bazel.settings.bazel.bazelProjectSettings
@@ -24,6 +31,7 @@ import kotlin.io.path.notExists
  */
 @Service(Service.Level.PROJECT)
 class ProjectViewService(private val project: Project) {
+  private val log = logger<ProjectViewService>()
   fun getDefaultProjectViewFileContent(): ProjectView {
     val content = ProjectViewFileUtils.projectViewTemplate(project).format(".")
     val psiFile = PsiFileFactory.getInstance(project)
@@ -69,20 +77,80 @@ class ProjectViewService(private val project: Project) {
 
   private fun parseProjectView(projectViewPath: Path): ProjectView {
     return runBlockingCancellable {
-      val projectView = readAction {
-        val virtualFile = VirtualFileManager.getInstance().findFileByNioPath(projectViewPath)
-          ?: return@readAction null
+      val virtualFile = VirtualFileManager.getInstance().findFileByNioPath(projectViewPath)
+        ?: return@runBlockingCancellable readAction { getDefaultProjectViewFileContent() }
+
+      val psiFile = readAction { PsiManager.getInstance(project).findFile(virtualFile) }
 
-        val psi = PsiManager.getInstance(project).findFile(virtualFile) as? ProjectViewPsiFile
-          ?: return@readAction null
+      ensureCorrectFileType(virtualFile, psiFile, projectViewPath)
 
-        return@readAction ProjectView.fromProjectViewPsiFile(psi)
+      val projectView = readAction {
+        val psi = psiFile as? ProjectViewPsiFile ?: return@readAction null
+        ProjectView.fromProjectViewPsiFile(psi)
       }
+
       return@runBlockingCancellable projectView
         ?: readAction { getDefaultProjectViewFileContent() }
     }
   }
 
+  /**
+   * Ensures that .bazelproject file has correct ProjectView file type.
+   * Attempts auto-fix if needed, throws exception if fails.
+   */
+  private fun ensureCorrectFileType(virtualFile: VirtualFile, psiFile: PsiFile?, projectViewPath: Path) {
+    if (psiFile is ProjectViewPsiFile) {
+      return
+    }
+
+    if (psiFile != null) {
+      log.warn("ProjectView file type not recognized: path=$projectViewPath, fileType=${virtualFile.fileType.name}, language=${psiFile.language}")
+
+      if (!tryAutoFixFileTypeRegistration(virtualFile)) {
+        throw IllegalStateException("""
+          .bazelproject file not recognized as ProjectView file type.
+
+          Please fix manually:
+          1. Go to Settings → Editor → File Types
+          2. Find "ProjectView file for Bazel project" in the list
+          3. Add "*.bazelproject" to File name patterns
+          4. Restart IDE and try sync again
+        """.trimIndent())
+      }
+    }
+  }
+
+  /**
+   * Attempts to auto-fix ProjectView file type registration by associating *.bazelproject pattern
+   * with ProjectViewFileType.
+   * 
+   * @param virtualFile the .bazelproject file that needs to be fixed
+   * @return true if auto-fix succeeded, false if it failed
+   */
+  private fun tryAutoFixFileTypeRegistration(virtualFile: VirtualFile): Boolean {
+    log.info("Attempting to auto-fix ProjectView file type registration...")
+
+    return try {
+      ApplicationManager.getApplication().invokeAndWait {
+        ApplicationManager.getApplication().runWriteAction {
+          val fileTypeManager = FileTypeManager.getInstance()
+          fileTypeManager.associatePattern(ProjectViewFileType, "*.bazelproject")
+        }
+      }
+
+      // Force refresh the virtual file to pick up new file type
+      virtualFile.refresh(false, false)
+
+      log.info("Auto-fix completed: file type registration updated")
+      true
+    } catch (e: ProcessCanceledException) {
+      throw e
+    } catch (e: Exception) {
+      log.warn("Auto-fix failed with exception: ${e.message}", e)
+      false
+    }
+  }
+
   fun getProjectViewConfigurationHash(): HashCode = ProjectViewHasher.hash(getProjectView())
 
   companion object {