/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the Source EULA. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/
import * as os from 'os';
import {ILogger} from './interfaces';
import * as Utils from './utils';
import {IExtensionConstants} from './contracts/contracts';
/*
* Logger class handles logging messages using the Util functions.
*/
export class Logger implements ILogger {
    private _writer: (message: string) => void;
    private _prefix: string;
    private _extensionConstants: IExtensionConstants;

    private _indentLevel: number = 0;
    private _indentSize: number = 4;
    private _atLineStart: boolean = false;

    constructor(writer: (message: string) => void, extensionConstants: IExtensionConstants, prefix?: string) {
        this._writer = writer;
        this._prefix = prefix;
        this._extensionConstants = extensionConstants;
    }

    public logDebug(message: string): void {
        Utils.logDebug(message, this._extensionConstants.extensionConfigSectionName);
    }

    private _appendCore(message: string): void {
        if (this._atLineStart) {
            if (this._indentLevel > 0) {
                const indent = ' '.repeat(this._indentLevel * this._indentSize);
                this._writer(indent);
            }

            if (this._prefix) {
                this._writer(`[${this._prefix}] `);
            }

            this._atLineStart = false;
        }

        this._writer(message);
    }

    public increaseIndent(): void {
        this._indentLevel += 1;
    }

    public decreaseIndent(): void {
        if (this._indentLevel > 0) {
            this._indentLevel -= 1;
        }
    }

    public append(message?: string): void {
        message = message || '';
        this._appendCore(message);
    }

    public appendLine(message?: string): void {
        message = message || '';
        this._appendCore(message + os.EOL);
        this._atLineStart = true;
    }
}