export default class Logger {
    constructor(config = {}) {
        this.levels = { debug: 0, info: 1, warn: 2, error: 3 };
        this.currentLevel = config.level || 'info';
        this.maxLogs = config.maxLogs || 100;
        this.enableRemote = config.enableRemote || false;
        this.remoteEndpoint = config.remoteEndpoint || '/api/logs';
        this._setupGlobalHandlers();
    }

    log(level, message, data = null) {
        const levelIndex = this.levels[level];
        const currentIndex = this.levels[this.currentLevel];

        if (levelIndex < currentIndex) return;

        const timestamp = new Date().toISOString();
        const entry = {
            timestamp,
            level,
            message,
            data,
            url: window.location.href,
            userAgent: navigator.userAgent
        };

        this._console(level, message, data);
        this._persistLog(entry);

        if (this.enableRemote && level === 'error') {
            this._sendRemote(entry);
        }
    }

    debug(message, data) { this.log('debug', message, data); }
    info(message, data) { this.log('info', message, data); }
    warn(message, data) { this.log('warn', message, data); }
    error(message, data) { this.log('error', message, data); }

    _console(level, message, data) {
        const logFn = console[level] || console.log;
        const timestamp = new Date().toISOString();
        const prefix = `[${timestamp}] [${level.toUpperCase()}]`;
        logFn(`${prefix} ${message}`, data || '');
    }

    _persistLog(entry) {
        if (typeof localStorage === 'undefined') return;

        try {
            const logs = JSON.parse(localStorage.getItem('app_logs') || '[]');
            logs.push(entry);

            if (logs.length > this.maxLogs) {
                logs.splice(0, logs.length - this.maxLogs);
            }

            localStorage.setItem('app_logs', JSON.stringify(logs));
        } catch (err) {
            console.error('Failed to persist log:', err);
        }
    }

    _sendRemote(entry) {
        fetch(this.remoteEndpoint, {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify(entry)
        }).catch(err => console.error('Remote logging failed:', err));
    }

    _setupGlobalHandlers() {
        window.addEventListener('error', (event) => {
            this.error(`JavaScript Error: ${event.message}`, {
                file: event.filename,
                line: event.lineno,
                column: event.colno,
                stack: event.error?.stack
            });
        });

        window.addEventListener('unhandledrejection', (event) => {
            this.error(`Unhandled Promise Rejection: ${event.reason}`, {
                stack: event.reason?.stack
            });
        });
    }

    exportLogs() {
        if (typeof localStorage === 'undefined') return [];
        return JSON.parse(localStorage.getItem('app_logs') || '[]');
    }

    clearLogs() {
        if (typeof localStorage !== 'undefined') {
            localStorage.removeItem('app_logs');
        }
    }
}