import {
    Inject,
    Injectable,
} from '@angular/core';

import { BrowserTypesEnum } from './browser-types.enum';

import {
    BrowserDetailsInterface,
    BrowserDetectionPatternsInterface,
} from './../../../models/index';

@Injectable()
export class BrowserDetectorService {
    private _browserType: BrowserTypesEnum;
    private _userAgentPatterns: BrowserDetectionPatternsInterface[] = [
        {
            name: 'Chrome',
            pattern: /Chrome\/([0-9\.]+)\s/,
        },
        {
            name: 'Edge',
            pattern: /Edge\/([0-9\.]+)$/,
        },
        {
            name: 'Firefox',
            pattern: /Firefox\/([0-9\.]+)$/,
        },
        {
            name: 'IE',
            pattern: /MSIE\s([0-9\.]+).|Trident.+rv:([0-9\.]+)./,
        },
        {
            name: 'Safari',
            pattern: /[^Chrome]\/([0-9\.]+)\sSafari/,
        },
        {
            name: 'IOS',
            pattern: /iPad|iPhone|iPod/,
        },
    ];

    constructor(
        @Inject('window')
        private _window: Window,
    ) {
        this._browserType =
            this._getBrowserType();
    }

    public isFirefox() {
        return this._browserType ===
            BrowserTypesEnum.Firefox;
    }

    public isSafari() {
        return this._browserType ===
            BrowserTypesEnum.Safari;
    }

    public isChrome() {
        return this._browserType ===
            BrowserTypesEnum.Chrome;
    }

    public getBrowserDetails(): BrowserDetailsInterface {
        const userAgent = this._window.navigator.userAgent;
        const patterns = this._userAgentPatterns;

        const browser: BrowserDetailsInterface = {
            name: 'unknown',
            version: 'unknown',
        };

        for (let i = this._userAgentPatterns.length; i--;) {
            const match = userAgent.match(patterns[i].pattern);
            if (match && match.length > 0) {
                browser.name = patterns[i].name;
                browser.version = match[2] || match[1];
                break;
            }
        }

        return browser;
    }

    public isIE() {
        return this.getBrowserDetails().name === 'IE';
    }

    public isIOS() {
        return this.getBrowserDetails().name === 'IOS';
    }

    private _getBrowserType() {
        const nativeWindow = this._window;
        if (nativeWindow.navigator.userAgent
            .match(/Firefox/)
        ) {
            return BrowserTypesEnum.Firefox;
        } else if (
            nativeWindow.navigator.userAgent.match(/Safari/) &&
            !nativeWindow.navigator.userAgent.match(/Chrome/)
        ) {
            return BrowserTypesEnum.Safari;
        }
        return BrowserTypesEnum.Chrome;
    }
}