//===----------------------------------------------------------------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2024 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//

import Foundation
import IndexStoreDB
@_spi(SourceKitLSP) package import LanguageServerProtocol
package import SKOptions
package import SourceKitLSP
import SwiftExtensions
package import SwiftSyntax
package import ToolchainRegistry

package actor DocumentationLanguageService: LanguageService, Sendable {
  /// The ``SourceKitLSPServer`` instance that created this `DocumentationLanguageService`.
  private(set) weak var sourceKitLSPServer: SourceKitLSPServer?

  let documentationManager: DocCDocumentationManager

  var documentManager: DocumentManager {
    get throws {
      guard let sourceKitLSPServer else {
        throw ResponseError.unknown("Connection to the editor closed")
      }
      return sourceKitLSPServer.documentManager
    }
  }

  package static var experimentalCapabilities: [String: LSPAny] {
    return [
      DoccDocumentationRequest.method: .dictionary(["version": .int(1)])
    ]
  }

  package init(
    sourceKitLSPServer: SourceKitLSPServer,
    toolchain: Toolchain,
    options: SourceKitLSPOptions,
    hooks: Hooks,
    workspace: Workspace
  ) async throws {
    self.sourceKitLSPServer = sourceKitLSPServer
    self.documentationManager = DocCDocumentationManager(buildServerManager: workspace.buildServerManager)
  }

  package nonisolated func canHandle(workspace: Workspace, toolchain: Toolchain) -> Bool {
    return true
  }

  package func initialize(
    _ initialize: InitializeRequest
  ) async throws -> InitializeResult {
    return InitializeResult(
      capabilities: ServerCapabilities()
    )
  }

  package func shutdown() async {
    // Nothing to tear down
  }

  package func addStateChangeHandler(
    handler: @escaping @Sendable (LanguageServerState, LanguageServerState) -> Void
  ) async {
    // There is no underlying language server with which to report state
  }

  package func openDocument(
    _ notification: DidOpenTextDocumentNotification,
    snapshot: DocumentSnapshot
  ) async {
    // The DocumentationLanguageService does not do anything with document events
  }

  package func closeDocument(_ notification: DidCloseTextDocumentNotification) async {
    // The DocumentationLanguageService does not do anything with document events
  }

  package func reopenDocument(_ notification: ReopenTextDocumentNotification) async {
    // The DocumentationLanguageService does not do anything with document events
  }

  package func syntacticTestItems(for snapshot: DocumentSnapshot) async -> [AnnotatedTestItem] {
    return []
  }

  package func syntacticPlaygrounds(
    for snapshot: DocumentSnapshot,
    in workspace: Workspace
  ) async -> [TextDocumentPlayground] {
    return []
  }

  package func changeDocument(
    _ notification: DidChangeTextDocumentNotification,
    preEditSnapshot: DocumentSnapshot,
    postEditSnapshot: DocumentSnapshot,
    edits: [SwiftSyntax.SourceEdit]
  ) async {
    // The DocumentationLanguageService does not do anything with document events
  }
}