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

import { MainThreadOutputServiceShape } from '../common/extHost.protocol';
import * as vscode from 'vscode';
import { URI } from 'vs/base/common/uri';
import { join } from 'vs/base/common/path';
import { OutputAppender } from 'vs/workbench/services/output/node/outputAppender';
import { toLocalISOString } from 'vs/base/common/date';
import { dirExists, mkdirp } from 'vs/base/node/pfs';
import { AbstractExtHostOutputChannel, IOutputChannelFactory, ExtHostPushOutputChannel } from 'vs/workbench/api/common/extHostOutput';

export class ExtHostOutputChannelBackedByFile extends AbstractExtHostOutputChannel {

	private _appender: OutputAppender;

	constructor(name: string, appender: OutputAppender, proxy: MainThreadOutputServiceShape) {
		super(name, false, URI.file(appender.file), proxy);
		this._appender = appender;
	}

	append(value: string): void {
		super.append(value);
		this._appender.append(value);
		this._onDidAppend.fire();
	}

	update(): void {
		this._appender.flush();
		super.update();
	}

	show(columnOrPreserveFocus?: vscode.ViewColumn | boolean, preserveFocus?: boolean): void {
		this._appender.flush();
		super.show(columnOrPreserveFocus, preserveFocus);
	}

	clear(): void {
		this._appender.flush();
		super.clear();
	}
}

export const LogOutputChannelFactory = new class implements IOutputChannelFactory {

	_namePool = 1;

	async createOutputChannel(name: string, logsLocation: URI, proxy: MainThreadOutputServiceShape): Promise<AbstractExtHostOutputChannel> {
		try {
			const outputDirPath = join(logsLocation.fsPath, `output_logging_${toLocalISOString(new Date()).replace(/-|:|\.\d+Z$/g, '')}`);
			const outputDir = await dirExists(outputDirPath).then(exists => exists ? exists : mkdirp(outputDirPath).then(() => true)).then(() => outputDirPath);
			const fileName = `${this._namePool++}-${name}`;
			const file = URI.file(join(outputDir, `${fileName}.log`));
			const appender = new OutputAppender(fileName, file.fsPath);
			return new ExtHostOutputChannelBackedByFile(name, appender, proxy);
		} catch (error) {
			// Do not crash if logger cannot be created
			console.log(error);
			return new ExtHostPushOutputChannel(name, proxy);
		}
	}
};