/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

import {
  TrackedRangeStickiness,
  IModelDeltaDecoration,
  IModelDecorationsChangeAccessor,
} from '../../../../vs/editor/common/model';
import { ModelDecorationOptions } from '../../../../vs/editor/common/model/textModel';
import { IDecorationProvider } from '../../../../vs/editor/contrib/folding/foldingModel';
import { ICodeEditor } from '../../../../vs/editor/browser/editorBrowser';
import { Codicon } from '../../../../vs/base/common/codicons';
import { localize } from '../../../../vs/nls';
import { registerIcon } from '../../../../vs/platform/theme/common/iconRegistry';
import { ThemeIcon } from '../../../../vs/platform/theme/common/themeService';

export const foldingExpandedIcon = registerIcon(
  'folding-expanded',
  Codicon.chevronDown,
  localize(
    'foldingExpandedIcon',
    'Icon for expanded ranges in the editor glyph margin.'
  )
);
export const foldingCollapsedIcon = registerIcon(
  'folding-collapsed',
  Codicon.chevronRight,
  localize(
    'foldingCollapsedIcon',
    'Icon for collapsed ranges in the editor glyph margin.'
  )
);
export class FoldingDecorationProvider implements IDecorationProvider {
  private static readonly COLLAPSED_VISUAL_DECORATION =
    ModelDecorationOptions.register({
      description: 'folding-collapsed-visual-decoration',
      stickiness: TrackedRangeStickiness.NeverGrowsWhenTypingAtEdges,
      afterContentClassName: 'inline-folded',
      isWholeLine: true,
      firstLineDecorationClassName: ThemeIcon.asClassName(foldingCollapsedIcon),
    });

  private static readonly COLLAPSED_HIGHLIGHTED_VISUAL_DECORATION =
    ModelDecorationOptions.register({
      description: 'folding-collapsed-highlighted-visual-decoration',
      stickiness: TrackedRangeStickiness.NeverGrowsWhenTypingAtEdges,
      afterContentClassName: 'inline-folded',
      className: 'folded-background',
      isWholeLine: true,
      firstLineDecorationClassName: ThemeIcon.asClassName(foldingCollapsedIcon),
    });

  private static readonly EXPANDED_AUTO_HIDE_VISUAL_DECORATION =
    ModelDecorationOptions.register({
      description: 'folding-expanded-auto-hide-visual-decoration',
      stickiness: TrackedRangeStickiness.NeverGrowsWhenTypingAtEdges,
      isWholeLine: true,
      firstLineDecorationClassName: ThemeIcon.asClassName(foldingExpandedIcon),
    });

  private static readonly EXPANDED_VISUAL_DECORATION =
    ModelDecorationOptions.register({
      description: 'folding-expanded-visual-decoration',
      stickiness: TrackedRangeStickiness.NeverGrowsWhenTypingAtEdges,
      isWholeLine: true,
      firstLineDecorationClassName:
        'alwaysShowFoldIcons ' + ThemeIcon.asClassName(foldingExpandedIcon),
    });

  private static readonly HIDDEN_RANGE_DECORATION =
    ModelDecorationOptions.register({
      description: 'folding-hidden-range-decoration',
      stickiness: TrackedRangeStickiness.NeverGrowsWhenTypingAtEdges,
    });

  public autoHideFoldingControls: boolean = true;

  public showFoldingHighlights: boolean = true;

  constructor(private readonly editor: ICodeEditor) {}

  getDecorationOption(
    isCollapsed: boolean,
    isHidden: boolean
  ): ModelDecorationOptions {
    if (isHidden) {
      return FoldingDecorationProvider.HIDDEN_RANGE_DECORATION;
    }
    if (isCollapsed) {
      return this.showFoldingHighlights
        ? FoldingDecorationProvider.COLLAPSED_HIGHLIGHTED_VISUAL_DECORATION
        : FoldingDecorationProvider.COLLAPSED_VISUAL_DECORATION;
    } else if (this.autoHideFoldingControls) {
      return FoldingDecorationProvider.EXPANDED_AUTO_HIDE_VISUAL_DECORATION;
    } else {
      return FoldingDecorationProvider.EXPANDED_VISUAL_DECORATION;
    }
  }

  deltaDecorations(
    oldDecorations: string[],
    newDecorations: IModelDeltaDecoration[]
  ): string[] {
    return this.editor.deltaDecorations(oldDecorations, newDecorations);
  }

  changeDecorations<T>(
    callback: (changeAccessor: IModelDecorationsChangeAccessor) => T
  ): T {
    return this.editor.changeDecorations(callback);
  }
}