/*---------------------------------------------------------
 * Copyright (C) Microsoft Corporation. All rights reserved.
 *--------------------------------------------------------*/

import * as path from 'path';
import { utils as coreUtils, chromeConnection } from 'vscode-chrome-debug-core';

const WIN_APPDATA = process.env.LOCALAPPDATA || '/';
const DEFAULT_CHROME_PATH = {
    LINUX: '/usr/bin/google-chrome',
    OSX: '/Applications/Google Chrome.app/Contents/MacOS/Google Chrome',
    WIN: 'C:\\Program Files\\Google\\Chrome\\Application\\chrome.exe',
    WIN_LOCALAPPDATA: path.join(WIN_APPDATA, 'Google\\Chrome\\Application\\chrome.exe'),
    WINx86: 'C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe',
};

export function getBrowserPath(): string {
    const platform = coreUtils.getPlatform();
    if (platform === coreUtils.Platform.OSX) {
        return coreUtils.existsSync(DEFAULT_CHROME_PATH.OSX) ? DEFAULT_CHROME_PATH.OSX : null;
    } else if (platform === coreUtils.Platform.Windows) {
        if (coreUtils.existsSync(DEFAULT_CHROME_PATH.WINx86)) {
            return DEFAULT_CHROME_PATH.WINx86;
        } else if (coreUtils.existsSync(DEFAULT_CHROME_PATH.WIN)) {
            return DEFAULT_CHROME_PATH.WIN;
        } else if (coreUtils.existsSync(DEFAULT_CHROME_PATH.WIN_LOCALAPPDATA)) {
            return DEFAULT_CHROME_PATH.WIN_LOCALAPPDATA;
        } else {
            return null;
        }
    } else {
        return coreUtils.existsSync(DEFAULT_CHROME_PATH.LINUX) ? DEFAULT_CHROME_PATH.LINUX : null;
    }
}

export class DebounceHelper {
    private waitToken: any; // TS can't decide whether Timer or number...

    constructor(private timeoutMs: number) { }

    /**
     * If not waiting already, call fn after the timeout
     */
    public wait(fn: () => any): void {
        if (!this.waitToken) {
            this.waitToken = setTimeout(() => {
                this.waitToken = null;
                fn();
            },
                this.timeoutMs);
        }
    }

    /**
     * If waiting for something, cancel it and call fn immediately
     */
    public doAndCancel(fn: () => any): void {
        if (this.waitToken) {
            clearTimeout(this.waitToken);
            this.waitToken = null;
        }

        fn();
    }
}

export const getTargetFilter = (targetTypes?: string[]): chromeConnection.ITargetFilter => {
    if (targetTypes) {
        return target => target && (!target.type || targetTypes.indexOf(target.type) !== -1);
    }

    return () => true;
};

export const defaultTargetFilter = getTargetFilter(['page']);