/*
 * Copyright 2021 Red Hat, Inc. and/or its affiliates.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import * as Monaco from "@kie-tooling-core/monaco-editor";
import "monaco-editor/dev/vs/editor/editor.main.css";
import { MONACO_FEEL_LANGUAGE, MONACO_FEEL_THEME, feelTheme, feelDefaultSuggestions, feelTokensConfig } from ".";

export type SuggestionProvider = (
  feelExpression: string,
  row: number,
  col: number
) => Monaco.languages.CompletionItem[];

export const initializeFeelLanguage = () => {
  Monaco.languages.register({
    id: MONACO_FEEL_LANGUAGE,
    aliases: [MONACO_FEEL_LANGUAGE, "feel", "feel-dmn"],
    mimetypes: ["text/feel"],
  });
};

export const initializeMonacoTheme = () => {
  Monaco.editor.defineTheme(MONACO_FEEL_THEME, feelTheme());
};

export const initializeFeelTokensProvider = () => {
  Monaco.languages.setMonarchTokensProvider(MONACO_FEEL_LANGUAGE, feelTokensConfig());
};

export const initializeFeelCompletionItemProvider = (suggestionProvider?: SuggestionProvider) => {
  const provideCompletionItems = (model: Monaco.editor.ITextModel, position: Monaco.Position) => {
    let completionItems = feelDefaultSuggestions();

    if (suggestionProvider) {
      const items = suggestionProvider(model.getValue(), position.lineNumber, position.column - 1);
      if (items.length > 0) {
        completionItems = items;
      }
    }

    return {
      suggestions: completionItems,
    };
  };

  Monaco.languages.registerCompletionItemProvider(MONACO_FEEL_LANGUAGE, {
    provideCompletionItems,
  });

  return provideCompletionItems;
};