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

import * as azdata from 'azdata';
import { Event, Emitter } from 'vs/base/common/event';
import { IAccountManagementService } from 'sql/platform/accounts/common/interfaces';
import { AccountProviderAddedEventParams, UpdateAccountListEventParams } from 'sql/platform/accounts/common/eventTypes';
import { coalesce } from 'vs/base/common/arrays';
import { ILogService } from 'vs/platform/log/common/log';

/**
 * View model for account dialog
 */
export class AccountViewModel {
	// EVENTING ///////////////////////////////////////////////////////
	private _addProviderEmitter: Emitter<AccountProviderAddedEventParams>;
	public get addProviderEvent(): Event<AccountProviderAddedEventParams> { return this._addProviderEmitter.event; }

	private _removeProviderEmitter: Emitter<azdata.AccountProviderMetadata>;
	public get removeProviderEvent(): Event<azdata.AccountProviderMetadata> { return this._removeProviderEmitter.event; }

	private _updateAccountListEmitter: Emitter<UpdateAccountListEventParams>;
	public get updateAccountListEvent(): Event<UpdateAccountListEventParams> { return this._updateAccountListEmitter.event; }

	constructor(@IAccountManagementService private _accountManagementService: IAccountManagementService, @ILogService private _logService: ILogService) {
		// Create our event emitters
		this._addProviderEmitter = new Emitter<AccountProviderAddedEventParams>();
		this._removeProviderEmitter = new Emitter<azdata.AccountProviderMetadata>();
		this._updateAccountListEmitter = new Emitter<UpdateAccountListEventParams>();

		// Register handlers for any changes to the providers or accounts
		this._accountManagementService.addAccountProviderEvent(arg => this._addProviderEmitter.fire(arg));
		this._accountManagementService.removeAccountProviderEvent(arg => this._removeProviderEmitter.fire(arg));
		this._accountManagementService.updateAccountListEvent(arg => this._updateAccountListEmitter.fire(arg));
	}

	// PUBLIC METHODS //////////////////////////////////////////////////////
	/**
	 * Loads an initial list of account providers and accounts from the account management service
	 * and fires an event after each provider/accounts has been loaded.
	 *
	 */
	public async initialize(): Promise<AccountProviderAddedEventParams[]> {
		// Load a baseline of the account provider metadata and accounts
		// 1) Get all the providers from the account management service
		// 2) For each provider, get the accounts
		// 3) Build parameters to add a provider and return it
		try {
			const metadata = await this._accountManagementService.getAccountProviderMetadata();
			const accounts = await Promise.all(metadata.map(async providerMetadata => {
				try {
					const accounts = await this._accountManagementService.getAccountsForProvider(providerMetadata.id);
					return <AccountProviderAddedEventParams>{
						addedProvider: providerMetadata,
						initialAccounts: accounts
					};
				} catch (err) {
					this._logService.warn(`Error getting accounts for provider ${providerMetadata.id} : ${err}`);
					return undefined;
				}
			}));
			return coalesce(accounts);
		} catch (err) {
			this._logService.warn(`Error getting account provider metadata : ${err}`);
			return [];
		}
	}
}