// *****************************************************************************
// Copyright (C) 2018 Ericsson and others.
//
// This program and the accompanying materials are made available under the
// terms of the Eclipse Public License v. 2.0 which is available at
// http://www.eclipse.org/legal/epl-2.0.
//
// This Source Code may also be made available under the following Secondary
// Licenses when the conditions for such availability set forth in the Eclipse
// Public License v. 2.0 are satisfied: GNU General Public License, version 2
// with the GNU Classpath Exception which is available at
// https://www.gnu.org/software/classpath/license.html.
//
// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0
// *****************************************************************************

import { injectable, inject } from '@theia/core/shared/inversify';
import URI from '@theia/core/lib/common/uri';
import { MaybeArray, UNTITLED_SCHEME, nls } from '@theia/core/lib/common';
import { LabelProvider } from '@theia/core/lib/browser';
import { FileStat } from '../../common/files';
import { DirNode } from '../file-tree';
import { OpenFileDialogFactory, OpenFileDialogProps, SaveFileDialogFactory, SaveFileDialogProps } from './file-dialog';
import { FileService } from '../file-service';
import { EnvVariablesServer } from '@theia/core/lib/common/env-variables';
import { UserWorkingDirectoryProvider } from '@theia/core/lib/browser/user-working-directory-provider';

export const FileDialogService = Symbol('FileDialogService');
export interface FileDialogService {

    showOpenDialog(props: OpenFileDialogProps & { canSelectMany: true }, folder?: FileStat): Promise<MaybeArray<URI> | undefined>;
    showOpenDialog(props: OpenFileDialogProps, folder?: FileStat): Promise<URI | undefined>;
    showOpenDialog(props: OpenFileDialogProps, folder?: FileStat): Promise<MaybeArray<URI> | undefined>;

    showSaveDialog(props: SaveFileDialogProps, folder?: FileStat): Promise<URI | undefined>

}

@injectable()
export class DefaultFileDialogService implements FileDialogService {

    @inject(EnvVariablesServer)
    protected readonly environments: EnvVariablesServer;

    @inject(FileService)
    protected readonly fileService: FileService;

    @inject(OpenFileDialogFactory) protected readonly openFileDialogFactory: OpenFileDialogFactory;
    @inject(LabelProvider) protected readonly labelProvider: LabelProvider;
    @inject(SaveFileDialogFactory) protected readonly saveFileDialogFactory: SaveFileDialogFactory;
    @inject(UserWorkingDirectoryProvider) protected readonly rootProvider: UserWorkingDirectoryProvider;

    async showOpenDialog(props: OpenFileDialogProps & { canSelectMany: true }, folder?: FileStat): Promise<MaybeArray<URI> | undefined>;
    async showOpenDialog(props: OpenFileDialogProps, folder?: FileStat): Promise<URI | undefined>;
    async showOpenDialog(props: OpenFileDialogProps, folder?: FileStat): Promise<MaybeArray<URI> | undefined> {
        const title = props.title || nls.localizeByDefault('Open');
        const rootNode = await this.getRootNode(folder);
        if (rootNode) {
            const dialog = this.openFileDialogFactory(Object.assign(props, { title }));
            await dialog.model.navigateTo(rootNode);
            const value = await dialog.open();
            if (value) {
                if (!Array.isArray(value)) {
                    return props.fileScheme ? value.uri.withScheme(props.fileScheme) : value.uri;
                }
                return value.map(node => props.fileScheme ? node.uri.withScheme(props.fileScheme) : node.uri);
            }
        }
        return undefined;
    }

    async showSaveDialog(props: SaveFileDialogProps, folder?: FileStat): Promise<URI | undefined> {
        const title = props.title || nls.localizeByDefault('Save');
        const rootNode = await this.getRootNode(folder);
        if (rootNode) {
            const dialog = this.saveFileDialogFactory(Object.assign(props, { title }));
            await dialog.model.navigateTo(rootNode);
            return dialog.open();
        }
        return undefined;
    }

    protected async getRootNode(folderToOpen?: FileStat): Promise<DirNode | undefined> {
        const folderExists = folderToOpen
            && folderToOpen.resource.scheme !== UNTITLED_SCHEME
            && await this.fileService.exists(folderToOpen.resource);
        const folder = folderToOpen && folderExists ? folderToOpen : {
            resource: await this.rootProvider.getUserWorkingDir(),
            isDirectory: true
        };
        const folderUri = folder.resource;
        const rootUri = folder.isDirectory ? folderUri : folderUri.parent;
        try {
            const rootStat = await this.fileService.resolve(rootUri);
            return DirNode.createRoot(rootStat);
        } catch { }
        return undefined;
    }
}