index.ts

// Copyright (c) Jupyter Development Team.
// Distributed under the terms of the Modified BSD License.

import {
  ILayoutRestorer,
  JupyterLab,
  JupyterLabPlugin
} from '@jupyterlab/application';

import { ICommandPalette, InstanceTracker } from '@jupyterlab/apputils';

import { CodeEditor, IEditorServices } from '@jupyterlab/codeeditor';

import { IConsoleTracker } from '@jupyterlab/console';

import {
  ISettingRegistry,
  MarkdownCodeBlocks,
  PathExt
} from '@jupyterlab/coreutils';

import { IDocumentWidget } from '@jupyterlab/docregistry';

import { IFileBrowserFactory } from '@jupyterlab/filebrowser';

import {
  FileEditor,
  FileEditorFactory,
  IEditorTracker,
  TabSpaceStatus
} from '@jupyterlab/fileeditor';

import { ILauncher } from '@jupyterlab/launcher';

import {
  IEditMenu,
  IFileMenu,
  IMainMenu,
  IRunMenu,
  IViewMenu
} from '@jupyterlab/mainmenu';

import { IStatusBar } from '@jupyterlab/statusbar';

import { JSONObject } from '@phosphor/coreutils';

import { Menu } from '@phosphor/widgets';

/**
 * The class name for the text editor icon from the default theme.
 */
const EDITOR_ICON_CLASS = 'jp-TextEditorIcon';

/**
 * The class name for the text editor icon from the default theme.
 */
const MARKDOWN_ICON_CLASS = 'jp-MarkdownIcon';

/**
 * The name of the factory that creates editor widgets.
 */
const FACTORY = 'Editor';

/**
 * The command IDs used by the fileeditor plugin.
 */
namespace CommandIDs {
  export const createNew = 'fileeditor:create-new';

  export const createNewMarkdown = 'fileeditor:create-new-markdown-file';

  export const changeFontSize = 'fileeditor:change-font-size';

  export const lineNumbers = 'fileeditor:toggle-line-numbers';

  export const lineWrap = 'fileeditor:toggle-line-wrap';

  export const changeTabs = 'fileeditor:change-tabs';

  export const matchBrackets = 'fileeditor:toggle-match-brackets';

  export const autoClosingBrackets = 'fileeditor:toggle-autoclosing-brackets';

  export const createConsole = 'fileeditor:create-console';

  export const runCode = 'fileeditor:run-code';

  export const markdownPreview = 'fileeditor:markdown-preview';
}

/**
 * The editor tracker extension.
 */
const plugin: JupyterLabPlugin<IEditorTracker> = {
  activate,
  id: '@jupyterlab/fileeditor-extension:plugin',
  requires: [
    IConsoleTracker,
    IEditorServices,
    IFileBrowserFactory,
    ILayoutRestorer,
    ISettingRegistry
  ],
  optional: [ICommandPalette, ILauncher, IMainMenu],
  provides: IEditorTracker,
  autoStart: true
};

/**
 * A plugin that provides a status item allowing the user to
 * switch tabs vs spaces and tab widths for text editors.
 */
export const tabSpaceStatus: JupyterLabPlugin<void> = {
  id: '@jupyterlab/fileeditor-extension:tab-space-status',
  autoStart: true,
  requires: [IStatusBar, IEditorTracker, ISettingRegistry],
  activate: (
    app: JupyterLab,
    statusBar: IStatusBar,
    editorTracker: IEditorTracker,
    settingRegistry: ISettingRegistry
  ) => {
    // Create a menu for switching tabs vs spaces.
    const menu = new Menu({ commands: app.commands });
    const command = 'fileeditor:change-tabs';
    const args: JSONObject = {
      insertSpaces: false,
      size: 4,
      name: 'Indent with Tab'
    };
    menu.addItem({ command, args });
    for (let size of [1, 2, 4, 8]) {
      let args: JSONObject = {
        insertSpaces: true,
        size,
        name: `Spaces: ${size} `
      };
      menu.addItem({ command, args });
    }

    // Create the status item.
    const item = new TabSpaceStatus({ menu });

    // Keep a reference to the code editor config from the settings system.
    const updateSettings = (settings: ISettingRegistry.ISettings): void => {
      const cached = settings.get('editorConfig').composite as Partial<
        CodeEditor.IConfig
      >;
      const config: CodeEditor.IConfig = {
        ...CodeEditor.defaultConfig,
        ...cached
      };
      item.model!.config = config;
    };
    Promise.all([
      settingRegistry.load('@jupyterlab/fileeditor-extension:plugin'),
      app.restored
    ]).then(([settings]) => {
      updateSettings(settings);
      settings.changed.connect(updateSettings);
    });

    // Add the status item.
    statusBar.registerStatusItem(
      '@jupyterlab/fileeditor-extension:tab-space-status',
      {
        item,
        align: 'right',
        rank: 1,
        isActive: () => {
          return (
            app.shell.currentWidget &&
            editorTracker.has(app.shell.currentWidget)
          );
        }
      }
    );
  }
};

/**
 * Export the plugins as default.
 */
const plugins: JupyterLabPlugin<any>[] = [plugin, tabSpaceStatus];
export default plugins;

/**
 * Activate the editor tracker plugin.
 */
function activate(
  app: JupyterLab,
  consoleTracker: IConsoleTracker,
  editorServices: IEditorServices,
  browserFactory: IFileBrowserFactory,
  restorer: ILayoutRestorer,
  settingRegistry: ISettingRegistry,
  palette: ICommandPalette,
  launcher: ILauncher | null,
  menu: IMainMenu | null
): IEditorTracker {
  const id = plugin.id;
  const namespace = 'editor';
  const factory = new FileEditorFactory({
    editorServices,
    factoryOptions: {
      name: FACTORY,
      fileTypes: ['markdown', '*'], // Explicitly add the markdown fileType so
      defaultFor: ['markdown', '*'] // it outranks the defaultRendered viewer.
    }
  });
  const { commands, restored } = app;
  const tracker = new InstanceTracker<IDocumentWidget<FileEditor>>({
    namespace
  });
  const isEnabled = () =>
    tracker.currentWidget !== null &&
    tracker.currentWidget === app.shell.currentWidget;

  let config = { ...CodeEditor.defaultConfig };

  // Handle state restoration.
  restorer.restore(tracker, {
    command: 'docmanager:open',
    args: widget => ({ path: widget.context.path, factory: FACTORY }),
    name: widget => widget.context.path
  });

  /**
   * Update the setting values.
   */
  function updateSettings(settings: ISettingRegistry.ISettings): void {
    let cached = settings.get('editorConfig').composite as Partial<
      CodeEditor.IConfig
    >;
    Object.keys(config).forEach((key: keyof CodeEditor.IConfig) => {
      config[key] =
        cached[key] === null || cached[key] === undefined
          ? CodeEditor.defaultConfig[key]
          : cached[key];
    });
    // Trigger a refresh of the rendered commands
    app.commands.notifyCommandChanged();
  }

  /**
   * Update the settings of the current tracker instances.
   */
  function updateTracker(): void {
    tracker.forEach(widget => {
      updateWidget(widget.content);
    });
  }

  /**
   * Update the settings of a widget.
   */
  function updateWidget(widget: FileEditor): void {
    const editor = widget.editor;
    Object.keys(config).forEach((key: keyof CodeEditor.IConfig) => {
      editor.setOption(key, config[key]);
    });
  }

  // Add a console creator to the File menu
  // Fetch the initial state of the settings.
  Promise.all([settingRegistry.load(id), restored])
    .then(([settings]) => {
      updateSettings(settings);
      updateTracker();
      settings.changed.connect(() => {
        updateSettings(settings);
        updateTracker();
      });
    })
    .catch((reason: Error) => {
      console.error(reason.message);
      updateTracker();
    });

  factory.widgetCreated.connect((sender, widget) => {
    widget.title.icon = EDITOR_ICON_CLASS;

    // Notify the instance tracker if restore data needs to update.
    widget.context.pathChanged.connect(() => {
      tracker.save(widget);
    });
    tracker.add(widget);
    updateWidget(widget.content);
  });
  app.docRegistry.addWidgetFactory(factory);

  // Handle the settings of new widgets.
  tracker.widgetAdded.connect((sender, widget) => {
    updateWidget(widget.content);
  });

  // Add a command to change font size.
  commands.addCommand(CommandIDs.changeFontSize, {
    execute: args => {
      const delta = Number(args['delta']);
      if (Number.isNaN(delta)) {
        console.error(
          `${CommandIDs.changeFontSize}: delta arg must be a number`
        );
        return;
      }
      const style = window.getComputedStyle(document.documentElement);
      const cssSize = parseInt(
        style.getPropertyValue('--jp-code-font-size'),
        10
      );
      const currentSize = config.fontSize || cssSize;
      config.fontSize = currentSize + delta;
      return settingRegistry
        .set(id, 'editorConfig', config)
        .catch((reason: Error) => {
          console.error(`Failed to set ${id}: ${reason.message}`);
        });
    },
    isEnabled,
    label: args => args['name'] as string
  });

  commands.addCommand(CommandIDs.lineNumbers, {
    execute: () => {
      config.lineNumbers = !config.lineNumbers;
      return settingRegistry
        .set(id, 'editorConfig', config)
        .catch((reason: Error) => {
          console.error(`Failed to set ${id}: ${reason.message}`);
        });
    },
    isEnabled,
    isToggled: () => config.lineNumbers,
    label: 'Line Numbers'
  });

  type wrappingMode = 'on' | 'off' | 'wordWrapColumn' | 'bounded';

  commands.addCommand(CommandIDs.lineWrap, {
    execute: args => {
      const lineWrap = (args['mode'] as wrappingMode) || 'off';
      config.lineWrap = lineWrap;
      return settingRegistry
        .set(id, 'editorConfig', config)
        .catch((reason: Error) => {
          console.error(`Failed to set ${id}: ${reason.message}`);
        });
    },
    isEnabled,
    isToggled: args => {
      const lineWrap = (args['mode'] as wrappingMode) || 'off';
      return config.lineWrap === lineWrap;
    },
    label: 'Word Wrap'
  });

  commands.addCommand(CommandIDs.changeTabs, {
    label: args => args['name'] as string,
    execute: args => {
      config.tabSize = (args['size'] as number) || 4;
      config.insertSpaces = !!args['insertSpaces'];
      return settingRegistry
        .set(id, 'editorConfig', config)
        .catch((reason: Error) => {
          console.error(`Failed to set ${id}: ${reason.message}`);
        });
    },
    isEnabled,
    isToggled: args => {
      const insertSpaces = !!args['insertSpaces'];
      const size = (args['size'] as number) || 4;
      return config.insertSpaces === insertSpaces && config.tabSize === size;
    }
  });

  commands.addCommand(CommandIDs.matchBrackets, {
    execute: () => {
      config.matchBrackets = !config.matchBrackets;
      return settingRegistry
        .set(id, 'editorConfig', config)
        .catch((reason: Error) => {
          console.error(`Failed to set ${id}: ${reason.message}`);
        });
    },
    label: 'Match Brackets',
    isEnabled,
    isToggled: () => config.matchBrackets
  });

  commands.addCommand(CommandIDs.autoClosingBrackets, {
    execute: () => {
      config.autoClosingBrackets = !config.autoClosingBrackets;
      return settingRegistry
        .set(id, 'editorConfig', config)
        .catch((reason: Error) => {
          console.error(`Failed to set ${id}: ${reason.message}`);
        });
    },
    label: 'Auto Close Brackets for Text Editor',
    isEnabled,
    isToggled: () => config.autoClosingBrackets
  });

  commands.addCommand(CommandIDs.createConsole, {
    execute: args => {
      const widget = tracker.currentWidget;

      if (!widget) {
        return;
      }

      return commands
        .execute('console:create', {
          activate: args['activate'],
          name: widget.context.contentsModel.name,
          path: widget.context.path,
          preferredLanguage: widget.context.model.defaultKernelLanguage,
          ref: widget.id,
          insertMode: 'split-bottom'
        })
        .then(console => {
          widget.context.pathChanged.connect((sender, value) => {
            console.session.setPath(value);
            console.session.setName(widget.context.contentsModel.name);
          });
        });
    },
    isEnabled,
    label: 'Create Console for Editor'
  });

  commands.addCommand(CommandIDs.runCode, {
    execute: () => {
      // Run the appropriate code, taking into account a ```fenced``` code block.
      const widget = tracker.currentWidget.content;

      if (!widget) {
        return;
      }

      let code = '';
      const editor = widget.editor;
      const path = widget.context.path;
      const extension = PathExt.extname(path);
      const selection = editor.getSelection();
      const { start, end } = selection;
      let selected = start.column !== end.column || start.line !== end.line;

      if (selected) {
        // Get the selected code from the editor.
        const start = editor.getOffsetAt(selection.start);
        const end = editor.getOffsetAt(selection.end);

        code = editor.model.value.text.substring(start, end);
      } else if (MarkdownCodeBlocks.isMarkdown(extension)) {
        const { text } = editor.model.value;
        const blocks = MarkdownCodeBlocks.findMarkdownCodeBlocks(text);

        for (let block of blocks) {
          if (block.startLine <= start.line && start.line <= block.endLine) {
            code = block.code;
            selected = true;
            break;
          }
        }
      }

      if (!selected) {
        // no selection, submit whole line and advance
        code = editor.getLine(selection.start.line);
        const cursor = editor.getCursorPosition();
        if (cursor.line + 1 === editor.lineCount) {
          let text = editor.model.value.text;
          editor.model.value.text = text + '\n';
        }
        editor.setCursorPosition({
          line: cursor.line + 1,
          column: cursor.column
        });
      }

      const activate = false;
      if (code) {
        return commands.execute('console:inject', { activate, code, path });
      } else {
        return Promise.resolve(void 0);
      }
    },
    isEnabled,
    label: 'Run Code'
  });

  commands.addCommand(CommandIDs.markdownPreview, {
    execute: () => {
      let widget = tracker.currentWidget;
      if (!widget) {
        return;
      }
      let path = widget.context.path;
      return commands.execute('markdownviewer:open', {
        path,
        options: {
          mode: 'split-right'
        }
      });
    },
    isVisible: () => {
      let widget = tracker.currentWidget;
      return (
        (widget && PathExt.extname(widget.context.path) === '.md') || false
      );
    },
    label: 'Show Markdown Preview'
  });

  // Function to create a new untitled text file, given
  // the current working directory.
  const createNew = (cwd: string, ext: string = 'txt') => {
    return commands
      .execute('docmanager:new-untitled', {
        path: cwd,
        type: 'file',
        ext
      })
      .then(model => {
        return commands.execute('docmanager:open', {
          path: model.path,
          factory: FACTORY
        });
      });
  };

  // Add a command for creating a new text file.
  commands.addCommand(CommandIDs.createNew, {
    label: args => (args['isPalette'] ? 'New Text File' : 'Text File'),
    caption: 'Create a new text file',
    iconClass: args => (args['isPalette'] ? '' : EDITOR_ICON_CLASS),
    execute: args => {
      let cwd = args['cwd'] || browserFactory.defaultBrowser.model.path;
      return createNew(cwd as string);
    }
  });

  // Add a command for creating a new Markdown file.
  commands.addCommand(CommandIDs.createNewMarkdown, {
    label: args => (args['isPalette'] ? 'New Markdown File' : 'Markdown File'),
    caption: 'Create a new markdown file',
    iconClass: args => (args['isPalette'] ? '' : MARKDOWN_ICON_CLASS),
    execute: args => {
      let cwd = args['cwd'] || browserFactory.defaultBrowser.model.path;
      return createNew(cwd as string, 'md');
    }
  });

  // Add a launcher item if the launcher is available.
  if (launcher) {
    launcher.add({
      command: CommandIDs.createNew,
      category: 'Other',
      rank: 1
    });

    launcher.add({
      command: CommandIDs.createNewMarkdown,
      category: 'Other',
      rank: 2
    });
  }

  if (palette) {
    const category = 'Text Editor';
    let args: JSONObject = {
      insertSpaces: false,
      size: 4,
      name: 'Indent with Tab'
    };
    let command = 'fileeditor:change-tabs';
    palette.addItem({ command, args, category });

    for (let size of [1, 2, 4, 8]) {
      let args: JSONObject = {
        insertSpaces: true,
        size,
        name: `Spaces: ${size} `
      };
      palette.addItem({ command, args, category });
    }

    args = { isPalette: true };
    command = CommandIDs.createNew;
    palette.addItem({ command, args, category });

    args = { isPalette: true };
    command = CommandIDs.createNewMarkdown;
    palette.addItem({ command, args, category });

    args = { name: 'Increase Font Size', delta: 1 };
    command = CommandIDs.changeFontSize;
    palette.addItem({ command, args, category });

    args = { name: 'Decrease Font Size', delta: -1 };
    command = CommandIDs.changeFontSize;
    palette.addItem({ command, args, category });
  }

  if (menu) {
    // Add the editing commands to the settings menu.
    const tabMenu = new Menu({ commands });
    tabMenu.title.label = 'Text Editor Indentation';
    let args: JSONObject = {
      insertSpaces: false,
      size: 4,
      name: 'Indent with Tab'
    };
    let command = 'fileeditor:change-tabs';
    tabMenu.addItem({ command, args });

    for (let size of [1, 2, 4, 8]) {
      let args: JSONObject = {
        insertSpaces: true,
        size,
        name: `Spaces: ${size} `
      };
      tabMenu.addItem({ command, args });
    }

    menu.settingsMenu.addGroup(
      [
        {
          command: CommandIDs.changeFontSize,
          args: { name: 'Increase Text Editor Font Size', delta: +1 }
        },
        {
          command: CommandIDs.changeFontSize,
          args: { name: 'Decrease Text Editor Font Size', delta: -1 }
        },
        { type: 'submenu', submenu: tabMenu },
        { command: CommandIDs.autoClosingBrackets }
      ],
      30
    );

    // Add new text file creation to the file menu.
    menu.fileMenu.newMenu.addGroup([{ command: CommandIDs.createNew }], 30);

    // Add new markdown file creation to the file menu.
    menu.fileMenu.newMenu.addGroup(
      [{ command: CommandIDs.createNewMarkdown }],
      30
    );

    // Add undo/redo hooks to the edit menu.
    menu.editMenu.undoers.add({
      tracker,
      undo: widget => {
        widget.content.editor.undo();
      },
      redo: widget => {
        widget.content.editor.redo();
      }
    } as IEditMenu.IUndoer<IDocumentWidget<FileEditor>>);

    // Add editor view options.
    menu.viewMenu.editorViewers.add({
      tracker,
      toggleLineNumbers: widget => {
        const lineNumbers = !widget.content.editor.getOption('lineNumbers');
        widget.content.editor.setOption('lineNumbers', lineNumbers);
      },
      toggleWordWrap: widget => {
        const oldValue = widget.content.editor.getOption('lineWrap');
        const newValue = oldValue === 'off' ? 'on' : 'off';
        widget.content.editor.setOption('lineWrap', newValue);
      },
      toggleMatchBrackets: widget => {
        const matchBrackets = !widget.content.editor.getOption('matchBrackets');
        widget.content.editor.setOption('matchBrackets', matchBrackets);
      },
      lineNumbersToggled: widget =>
        widget.content.editor.getOption('lineNumbers'),
      wordWrapToggled: widget =>
        widget.content.editor.getOption('lineWrap') !== 'off',
      matchBracketsToggled: widget =>
        widget.content.editor.getOption('matchBrackets')
    } as IViewMenu.IEditorViewer<IDocumentWidget<FileEditor>>);

    // Add a console creator the the Kernel menu.
    menu.fileMenu.consoleCreators.add({
      tracker,
      name: 'Editor',
      createConsole: current => {
        const options = {
          path: current.context.path,
          preferredLanguage: current.context.model.defaultKernelLanguage
        };
        return commands.execute('console:create', options);
      }
    } as IFileMenu.IConsoleCreator<IDocumentWidget<FileEditor>>);

    // Add a code runner to the Run menu.
    menu.runMenu.codeRunners.add({
      tracker,
      noun: 'Code',
      isEnabled: current => {
        let found = false;
        consoleTracker.forEach(console => {
          if (console.console.session.path === current.context.path) {
            found = true;
          }
        });
        return found;
      },
      run: () => commands.execute(CommandIDs.runCode)
    } as IRunMenu.ICodeRunner<IDocumentWidget<FileEditor>>);
  }

  app.contextMenu.addItem({
    command: CommandIDs.createConsole,
    selector: '.jp-FileEditor'
  });
  app.contextMenu.addItem({
    command: CommandIDs.markdownPreview,
    selector: '.jp-FileEditor'
  });

  return tracker;
}