// Copyright (c) 2018, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'dart:convert';
import 'dart:io';

import 'package:args/args.dart';
import 'package:http/http.dart' as http;
import 'package:path/path.dart' as path;

import 'codegen_dart.dart';
import 'meta_model.dart';

Future<void> main(List<String> arguments) async {
  var args = argParser.parse(arguments);
  var help = args[argHelp] as bool;
  if (help) {
    print(argParser.usage);
    return;
  }

  var outFolder = path.join(languageServerProtocolPackagePath, 'lib');
  Directory(outFolder).createSync();

  // Collect definitions for types in the model and our custom extensions.
  var specTypes = await getSpecClasses(args);
  var customTypes = getCustomClasses();

  // Record both sets of types in dictionaries for faster lookups, but also so
  // they can reference each other and we can find the definitions during
  // codegen.
  recordTypes(specTypes);
  recordTypes(customTypes);

  // Generate formatted Dart code (as a string) for each set of types.
  var specTypesOutput = generateDartForTypes(specTypes);
  var customTypesOutput = generateDartForTypes(customTypes);

  File(path.join(outFolder, 'protocol_generated.dart')).writeAsStringSync(
    generatedFileHeader(2018, importCustom: true) + specTypesOutput,
  );
  File(
    path.join(outFolder, 'protocol_custom_generated.dart'),
  ).writeAsStringSync(generatedFileHeader(2019) + customTypesOutput);
}

const argDownload = 'download';

const argHelp = 'help';

final argParser =
    ArgParser()
      ..addFlag(argHelp, hide: true)
      ..addFlag(
        argDownload,
        negatable: false,
        abbr: 'd',
        help:
            'Download the latest version of the LSP spec before generating types',
      );

final String languageServerProtocolPackagePath = path.join(
  sdkRootPath,
  'third_party',
  'pkg',
  'language_server_protocol',
);

final String licenseComment = LineSplitter.split(
      File(localLicensePath).readAsStringSync(),
    )
    .skipWhile(
      (line) =>
          line !=
          'Files: lib/protocol_custom_generated.dart, lib/protocol_generated.dart',
    )
    .skip(2)
    .map((line) => line.isEmpty ? '//' : '// $line')
    .join('\n');

final String localLicensePath = '$languageServerProtocolPackagePath/LICENSE';
final String localSpecPath =
    '$languageServerProtocolPackagePath/lsp_meta_model.json';

final String sdkRootPath =
    File(Platform.script.toFilePath()).parent.parent.parent.parent.parent.path;

final Uri specLicenseUri = Uri.parse(
  'https://microsoft.github.io/language-server-protocol/License-code.txt',
);

/// The URI of the version of the LSP meta model to generate from. This should
/// be periodically updated to the latest version.
final Uri specUri = Uri.parse(
  'https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/metaModel/metaModel.json',
);

Future<void> downloadSpec() async {
  var specResp = await http.get(specUri);
  var licenseResp = await http.get(specLicenseUri);

  assert(specResp.statusCode == 200);
  assert(licenseResp.statusCode == 200);

  var dartSdkLicense = await File('$sdkRootPath/LICENSE').readAsString();
  await File(localSpecPath).writeAsString(specResp.body);
  await File(localLicensePath).writeAsString('''
$dartSdkLicense

------------------

Files: lsp_meta_model.json
Files: lib/protocol_custom_generated.dart, lib/protocol_generated.dart

${licenseResp.body}
''');
}

String generatedFileHeader(int year, {bool importCustom = false}) => '''
$licenseComment

// This file has been automatically generated. Please do not edit it manually.
// To regenerate the file, use the script
// "pkg/analysis_server/tool/lsp_spec/generate_all.dart".

// ignore_for_file: constant_identifier_names

import 'dart:convert' show JsonEncoder;

import 'package:collection/collection.dart';
import 'package:language_server_protocol/json_parsing.dart';
import 'package:language_server_protocol/protocol_special.dart';
import 'package:language_server_protocol/protocol${importCustom ? '_custom' : ''}_generated.dart';

const jsonEncoder = JsonEncoder.withIndent('    ');

''';

List<LspEntity> getCustomClasses() {
  /// Helper to create an interface type.
  Interface interface(
    String name,
    List<Member> fields, {
    String? baseType,
    String? comment,
    bool abstract = false,
  }) {
    return Interface(
      name: name,
      abstract: abstract,
      comment: comment,
      baseTypes: [if (baseType != null) TypeReference(baseType)],
      members: fields,
    );
  }

  /// Helper to create a field.
  Field field(
    String name, {
    String? comment,
    required String type,
    bool array = false,
    bool literal = false,
    bool canBeNull = false,
    bool canBeUndefined = false,
  }) {
    var fieldType =
        array
            ? ArrayType(TypeReference(type))
            : literal
            ? LiteralType(TypeReference.string, type)
            : TypeReference(type);

    return Field(
      name: name,
      comment: comment,
      type: fieldType,
      allowsNull: canBeNull,
      allowsUndefined: canBeUndefined,
    );
  }

  var customTypes = <LspEntity>[
    TypeAlias(
      name: 'LSPAny',
      baseType: TypeReference.LspAny,
      renameReferences: false,
    ),
    TypeAlias(
      name: 'LSPObject',
      baseType: TypeReference.LspObject,
      renameReferences: false,
    ),
    // The DocumentFilter more complex in v3.17's meta_model (to allow
    // TextDocumentFilters to be guaranteed to have at least one of language,
    // pattern, scheme) but we only ever use a single type in the server so
    // for compatibility, alias that type to the original TS-spec name.
    // TODO(dantup): Improve this after the TS->JSON Spec migration.
    TypeAlias(
      name: 'DocumentFilter',
      baseType: TypeReference('TextDocumentFilterScheme'),
      renameReferences: true,
    ),
    // Similarly, the meta_model includes String as an option for
    // DocumentSelector which is deprecated and we never previously supported
    // (because the TypeScript spec did not include it in the type) so preserve
    // that.
    // TODO(dantup): Improve this after the TS->JSON Spec migration.
    TypeAlias(
      name: 'DocumentSelector',
      baseType: ArrayType(TypeReference('TextDocumentFilterScheme')),
      renameReferences: true,
    ),
    interface('Message', [
      field('jsonrpc', type: 'string'),
      field('clientRequestTime', type: 'int', canBeUndefined: true),
    ]),
    interface('IncomingMessage', [
      field('method', type: 'Method'),
      field('params', type: 'LSPAny', canBeUndefined: true),
    ], baseType: 'Message'),
    interface('RequestMessage', [
      Field(
        name: 'id',
        type: UnionType([TypeReference.int, TypeReference.string]),
        allowsNull: false,
        allowsUndefined: false,
      ),
    ], baseType: 'IncomingMessage'),
    interface('NotificationMessage', [], baseType: 'IncomingMessage'),
    interface('ResponseMessage', [
      Field(
        name: 'id',
        type: UnionType([TypeReference.int, TypeReference.string]),
        allowsNull: true,
        allowsUndefined: false,
      ),
      field('result', type: 'LSPAny', canBeUndefined: true),
      field('error', type: 'ResponseError', canBeUndefined: true),
    ], baseType: 'Message'),
    interface('ResponseError', [
      field('code', type: 'ErrorCodes'),
      field('message', type: 'string'),
      // This is Object? normally, but since this class can be serialized
      // we will crash if it data is set to something that can't be converted to
      // JSON (for ex. Uri) so this forces anyone setting this to convert to a
      // String.
      field(
        'data',
        type: 'string',
        canBeUndefined: true,
        comment:
            'A string that contains additional information about the error. '
            'Can be omitted.',
      ),
    ]),
    TypeAlias(
      name: 'DocumentUri',
      baseType: TypeReference('Uri'),
      renameReferences: false,
    ),
    // The LSP Spec uses "URI" but since that's fairly generic and will show up
    // everywhere in code completion, we rename it to "LspUri" before using
    // a typedef onto the Dart URI class.
    TypeAlias(
      name: 'URI',
      baseType: TypeReference('LSPUri'),
      renameReferences: true,
    ),
    TypeAlias(
      name: 'LSPUri',
      baseType: TypeReference('Uri'),
      renameReferences: false,
    ),

    interface('ConnectToDtdParams', [
      field('uri', type: 'Uri'),
      field(
        'registerExperimentalHandlers',
        type: 'boolean',
        canBeUndefined: true,
        comment:
            'Whether to register experimental LSP handlers with DTD. '
            'This should not be set by clients automatically but opt-in for '
            'users that are developing/testing incomplete functionality.',
      ),
    ]),
    interface('DartDiagnosticServer', [field('port', type: 'int')]),
    interface('AnalyzerStatusParams', [field('isAnalyzing', type: 'boolean')]),
    interface('PublishClosingLabelsParams', [
      field('uri', type: 'Uri'),
      field('labels', type: 'ClosingLabel', array: true),
    ]),
    interface('OpenUriParams', [field('uri', type: 'Uri')]),
    interface('ClosingLabel', [
      field('range', type: 'Range'),
      field('label', type: 'string'),
    ]),
    interface('Element', [
      field('range', type: 'Range', canBeUndefined: true),
      field('name', type: 'string'),
      field('kind', type: 'string'),
      field('parameters', type: 'string', canBeUndefined: true),
      field('typeParameters', type: 'string', canBeUndefined: true),
      field('returnType', type: 'string', canBeUndefined: true),
    ]),
    interface('PublishOutlineParams', [
      field('uri', type: 'Uri'),
      field('outline', type: 'Outline'),
    ]),
    interface('Outline', [
      field('element', type: 'Element'),
      field('range', type: 'Range'),
      field('codeRange', type: 'Range'),
      field('children', type: 'Outline', array: true, canBeUndefined: true),
    ]),
    interface('PublishFlutterOutlineParams', [
      field('uri', type: 'Uri'),
      field('outline', type: 'FlutterOutline'),
    ]),
    interface('FlutterOutline', [
      field('kind', type: 'string'),
      field('label', type: 'string', canBeUndefined: true),
      field('className', type: 'string', canBeUndefined: true),
      field('variableName', type: 'string', canBeUndefined: true),
      field(
        'attributes',
        type: 'FlutterOutlineAttribute',
        array: true,
        canBeUndefined: true,
      ),
      field('dartElement', type: 'Element', canBeUndefined: true),
      field('range', type: 'Range'),
      field('codeRange', type: 'Range'),
      field(
        'children',
        type: 'FlutterOutline',
        array: true,
        canBeUndefined: true,
      ),
    ]),
    interface('FlutterOutlineAttribute', [
      field('name', type: 'string'),
      field('label', type: 'string'),
      field('valueRange', type: 'Range', canBeUndefined: true),
    ]),
    interface(
      // Used as a base class for all resolution data classes.
      'CompletionItemResolutionInfo',
      [],
    ),
    interface('DartCompletionResolutionInfo', [
      field(
        'file',
        type: 'string',
        comment:
            'The file where the completion is being inserted.\n\n'
            'This is used to compute where to add the import.',
      ),
      field(
        'importUris',
        type: 'string',
        array: true,
        comment: 'The URIs to be imported if this completion is selected.',
      ),
      field(
        'ref',
        type: 'string',
        canBeUndefined: true,
        comment:
            'The encoded ElementLocation2 of the item being completed.\n\n'
            'This is used to provide documentation in the resolved response.',
      ),
    ], baseType: 'CompletionItemResolutionInfo'),
    interface(
      'PubPackageCompletionItemResolutionInfo',
      [field('packageName', type: 'string')],
      baseType: 'CompletionItemResolutionInfo',
    ),
    // Custom types for experimental SnippetTextEdits
    // https://github.com/rust-analyzer/rust-analyzer/blob/b35559a2460e7f0b2b79a7029db0c5d4e0acdb44/docs/dev/lsp-extensions.md#snippet-textedit
    interface('SnippetTextEdit', [
      field('insertTextFormat', type: 'InsertTextFormat'),
    ], baseType: 'TextEdit'),
    // Return type for refactor.validate command.
    interface('ValidateRefactorResult', [
      field('valid', type: 'boolean'),
      field('message', type: 'string', canBeUndefined: true),
    ]),
    interface('TypeHierarchyAnchor', [
      field(
        'ref',
        type: 'string',
        comment: 'The ElementLocation for this anchor element.',
      ),
      field(
        'path',
        type: 'int',
        array: true,
        comment: 'Indices used to navigate from this anchor to the element.',
      ),
    ]),
    interface('TypeHierarchyItemInfo', [
      field(
        'ref',
        type: 'string',
        comment:
            'The ElementLocation for this element, used to re-locate the '
            'element when subtypes/supertypes are '
            'fetched later.',
      ),
      field(
        'anchor',
        type: 'TypeHierarchyAnchor',
        comment:
            'An anchor element that can be used to navigate to this element '
            'preserving type arguments.',
        canBeUndefined: true,
      ),
    ]),
    interface('EditableArguments', [
      field('textDocument', type: 'TextDocumentIdentifier'),
      field('name', type: 'string', canBeUndefined: true),
      field('documentation', type: 'string', canBeUndefined: true),
      // TODO(dantup): field('refactors', ...),
      field('arguments', type: 'EditableArgument', array: true),
    ]),
    interface('EditableArgument', [
      field(
        'name',
        type: 'string',
        comment: 'The name of the corresponding parameter.',
      ),
      field(
        'type',
        type: 'string',
        comment:
            'The kind of parameter. This is not necessarily the Dart type, '
            'it is from a defined set of values that clients may understand '
            'how to edit.',
      ),
      Field(
        name: 'value',
        type: TypeReference.LspAny,
        allowsNull: false,
        allowsUndefined: true,
        comment:
            'The current value for this argument. This is only included if '
            'an explicit value is given in the code and is a valid literal for '
            'the kind of parameter. For expressions or named constants, this '
            'will not be included and displayValue can be shown as the current '
            'value instead.',
      ),
      field(
        'hasArgument',
        type: 'boolean',
        comment:
            'Whether an explicit argument exists for this parameter in the '
            'code. This will be true even if the explicit argument is the same '
            'value as the parameter default.',
      ),
      field(
        'isDefault',
        type: 'boolean',
        comment:
            'Whether the value is the default for this parameter, either '
            'because there is no argument or because it is explicitly provided '
            'as the same value.',
      ),
      field(
        'displayValue',
        type: 'string',
        canBeUndefined: true,
        comment:
            'A string that can be displayed to indicate the value for this '
            'argument. This will be populated in cases where the source code '
            'is not literally the same as the value field, for example an '
            'expression or named constant.',
      ),
      field(
        'isRequired',
        type: 'boolean',
        comment: 'Whether an argument is required for this parameter.',
      ),
      field(
        'isNullable',
        type: 'boolean',
        comment:
            'Whether this argument can be `null`. It is possible for an '
            'argument to be required, but still allow an explicit `null`.',
      ),
      field(
        'isEditable',
        type: 'boolean',
        comment:
            'Whether this argument can be add/edited. If not, '
            'notEditableReason will contain an explanation for why.',
      ),
      field(
        'notEditableReason',
        type: 'String',
        canBeUndefined: true,
        comment:
            'If isEditable is false, contains a human-readable '
            'description of why.',
      ),
      field(
        'options',
        type: 'string',
        array: true,
        canBeUndefined: true,
        comment:
            'The set of values allowed for this argument if it is an enum. '
            'Values are qualified in the form `EnumName.valueName`.',
      ),
      // TODO(dantup): field('properties', ...),
    ]),
    interface('EditArgumentParams', [
      field('textDocument', type: 'TextDocumentIdentifier'),
      field('position', type: 'Position'),
      field('edit', type: 'ArgumentEdit'),
    ]),
    interface('ArgumentEdit', [
      field('name', type: 'string'),
      Field(
        name: 'newValue',
        type: TypeReference.LspAny,
        allowsNull: true,
        allowsUndefined: false,
      ),
    ]),
    TypeAlias(
      name: 'TextDocumentEditEdits',
      baseType: ArrayType(
        UnionType([
          TypeReference('SnippetTextEdit'),
          TypeReference('AnnotatedTextEdit'),
          TypeReference('TextEdit'),
        ]),
      ),
      renameReferences: false,
    ),
    //
    // Command parameter support
    //
    interface(
      'CommandParameter',
      [
        field(
          'parameterLabel',
          type: 'String',
          comment:
              'A human-readable label to be displayed in the UI affordance '
              'used to prompt the user for the value of the parameter.',
        ),
        AbstractGetter(
          name: 'kind',
          type: TypeReference.string,
          comment:
              'The kind of this parameter. The client may use different '
              'UIs based on this value.',
        ),
        AbstractGetter(
          name: 'defaultValue',
          type: TypeReference.LspAny,
          comment:
              'An optional default value for the parameter. The type of '
              'this value may vary between parameter kinds but must always be '
              'something that can be converted directly to/from JSON.',
        ),
      ],
      abstract: true,
      comment:
          'Information about one of the arguments needed by the command.'
          '\n\n'
          'A list of parameters is sent in the `data` field of the '
          '`CodeAction` returned by the server. The values of the parameters '
          'should appear in the `args` field of the `Command` sent to the '
          'server in the same order as the corresponding parameters.',
    ),
    interface(
      'SaveUriCommandParameter',
      [
        field('kind', type: 'saveUri', literal: true),
        field(
          'defaultValue',
          type: 'String',
          canBeNull: true,
          canBeUndefined: true,
          comment: 'An optional default URI for the parameter.',
        ),
        field(
          'parameterTitle',
          type: 'String',
          comment: 'A title that may be displayed on a file dialog.',
        ),
        field(
          'actionLabel',
          type: 'String',
          comment: 'A label for the file dialogs action button.',
        ),
        Field(
          name: 'filters',
          type: MapType(TypeReference.string, ArrayType(TypeReference.string)),
          allowsNull: true,
          allowsUndefined: true,
          comment:
              'A set of file filters for a file dialog. '
              'Keys of the map are textual names ("Dart") and the value '
              'is a list of file extensions (["dart"]).',
        ),
      ],
      baseType: 'CommandParameter',
      comment: 'Information about a Save URI argument needed by the command.',
    ),
    interface('DartTextDocumentContentProviderRegistrationOptions', [
      field(
        'schemes',
        type: 'string',
        array: true,
        comment:
            'A set of URI schemes the server can provide content for. '
            'The server may also return URIs with these schemes in responses '
            'to other requests.',
      ),
    ]),
    interface('DartTextDocumentContentParams', [
      field('uri', type: 'DocumentUri'),
    ]),
    interface('DartTextDocumentContent', [
      field('content', type: 'String', canBeNull: true),
    ]),
    interface('DartTextDocumentContentDidChangeParams', [
      field('uri', type: 'DocumentUri'),
    ]),
  ];
  return customTypes;
}

Future<List<LspEntity>> getSpecClasses(ArgResults args) async {
  var download = args[argDownload] as bool;
  if (download) {
    await downloadSpec();
  }

  var file = File(localSpecPath);
  var model = LspMetaModelReader().readFile(file);
  model = LspMetaModelCleaner().cleanModel(model);

  return model.types;
}

class AbstractGetter extends Member {
  // ignore:unreachable_from_main
  final TypeBase type;

  AbstractGetter({
    required super.name,
    super.comment,
    super.isProposed,
    required this.type,
  });
}