/**
 * Modern colored logger — structured output with ANSI styling.
 * Never log: passwords, tokens, keys, user content, or raw error objects.
 */

type LogLevel = 'info' | 'warn' | 'error' | 'debug';

const C = {
  reset: '\x1b[0m',
  dim: '\x1b[2m',
  bold: '\x1b[1m',
  red: '\x1b[31m',
  green: '\x1b[32m',
  yellow: '\x1b[33m',
  blue: '\x1b[34m',
  magenta: '\x1b[35m',
  cyan: '\x1b[36m',
  white: '\x1b[37m',
  gray: '\x1b[90m',
  bgRed: '\x1b[41m',
  bgGreen: '\x1b[42m',
  bgYellow: '\x1b[43m',
  bgBlue: '\x1b[44m',
  bgMagenta: '\x1b[45m',
  bgCyan: '\x1b[46m',
};

const LEVEL_STYLES: Record<LogLevel, { icon: string; color: string; bg: string; label: string }> = {
  info:  { icon: '●', color: C.green,  bg: C.bgGreen,  label: ' INFO ' },
  warn:  { icon: '▲', color: C.yellow, bg: C.bgYellow, label: ' WARN ' },
  error: { icon: '✖', color: C.red,   bg: C.bgRed,    label: ' ERROR' },
  debug: { icon: '◆', color: C.cyan,  bg: C.bgCyan,   label: ' DEBUG' },
};

function timestamp(): string {
  return new Date().toLocaleTimeString('en-US', { hour12: false, hour: '2-digit', minute: '2-digit', second: '2-digit' });
}

function formatLevel(level: LogLevel): string {
  const s = LEVEL_STYLES[level];
  return `${s.bg}${C.bold}${C.white} ${s.icon} ${s.label} ${C.reset}`;
}

function formatContext(ctx?: string): string {
  if (!ctx) return '';
  return `${C.gray}[${C.cyan}${ctx}${C.gray}]${C.reset} `;
}

function formatMessage(msg: string): string {
  return `${C.white}${msg}${C.reset}`;
}

function log(level: LogLevel, message: string, context?: string): void {
  const ts = `${C.dim}${timestamp()}${C.reset}`;
  const lvl = formatLevel(level);
  const ctx = formatContext(context);
  const msg = formatMessage(message);
  const line = `${C.dim}┌─${C.reset} ${ts} ${lvl} ${ctx}${msg}`;

  if (level === 'error') {
    console.error(line);
  } else if (level === 'warn') {
    console.warn(line);
  } else {
    console.log(line);
  }
}

export function logInfo(message: string, context?: string) {
  log('info', message, context);
}

export function logWarn(message: string, context?: string) {
  log('warn', message, context);
}

export function logError(message: string, context?: string) {
  log('error', message, context);
}

export function logDebug(message: string, context?: string) {
  log('debug', message, context);
}

// ─── Request Logger Middleware ───────────────────────────────────────────────

export function requestLogger() {
  return (req: any, _res: any, next: () => void) => {
    const method = req.method;
    const url = req.originalUrl || req.url;

    const METHOD_COLORS: Record<string, string> = {
      GET: C.green,
      POST: C.blue,
      PUT: C.yellow,
      DELETE: C.red,
      PATCH: C.magenta,
      OPTIONS: C.gray,
    };

    const color = METHOD_COLORS[method] || C.white;
    const ts = `${C.dim}${timestamp()}${C.reset}`;
    const methodStr = `${color}${C.bold}${method.padEnd(7)}${C.reset}`;
    const urlStr = `${C.white}${url}${C.reset}`;
    const ip = req.ip || req.connection?.remoteAddress || '';

    console.log(`${C.dim}┌─${C.reset} ${ts} ${C.bgBlue}${C.bold}${C.white} REQ  ${C.reset} ${methodStr} ${urlStr} ${C.dim}${C.gray}← ${ip}${C.reset}`);

    next();
  };
}

// ─── Server Banner ──────────────────────────────────────────────────────────

export function printBanner(port: string | number, env: string) {
  const isProd = env === 'production';
  const envColor = isProd ? C.red : C.green;
  const envLabel = isProd ? 'PRODUCTION' : 'DEVELOPMENT';

  const line = `${C.dim}────────────────────────────────────────────${C.reset}`;

  console.log('');
  console.log(`${C.blue}${C.bold}  ╔══════════════════════════════════════════╗${C.reset}`);
  console.log(`${C.blue}${C.bold}  ║${C.reset}  ${C.cyan}${C.bold}MASAR${C.reset} ${C.dim}·${C.reset} ${C.white}Backend API${C.reset}                              ${C.blue}${C.bold}║${C.reset}`);
  console.log(`${C.blue}${C.bold}  ╠══════════════════════════════════════════╣${C.reset}`);
  console.log(`${C.blue}${C.bold}  ║${C.reset}                                          ${C.blue}${C.bold}║${C.reset}`);
  console.log(`${C.blue}${C.bold}  ║${C.reset}  ${C.gray}Status${C.reset}    ${C.green}${C.bold}● RUNNING${C.reset}                                ${C.blue}${C.bold}║${C.reset}`);
  console.log(`${C.blue}${C.bold}  ║${C.reset}  ${C.gray}Port${C.reset}      ${C.white}${C.bold}${port}${C.reset}                                       ${C.blue}${C.bold}║${C.reset}`);
  console.log(`${C.blue}${C.bold}  ║${C.reset}  ${C.gray}Environment${C.reset}  ${envColor}${C.bold}${envLabel}${C.reset}                             ${C.blue}${C.bold}║${C.reset}`);
  console.log(`${C.blue}${C.bold}  ║${C.reset}  ${C.gray}Time${C.reset}      ${C.white}${new Date().toLocaleString('en-US', { timeZone: 'Asia/Baghdad' })}${C.reset}              ${C.blue}${C.bold}║${C.reset}`);
  console.log(`${C.blue}${C.bold}  ║${C.reset}                                          ${C.blue}${C.bold}║${C.reset}`);
  console.log(`${C.blue}${C.bold}  ╠══════════════════════════════════════════╣${C.reset}`);

  const routes: [string, string, string, string][] = [
    ['GET', '/api/health', C.green, 'Health check'],
    ['POST', '/api/auth/*', C.blue, 'Authentication'],
    ['GET', '/api/users/*', C.green, 'User profiles'],
    ['GET', '/api/courses/*', C.green, 'Course content'],
    ['POST', '/api/challenges/*', C.blue, 'Challenge submit'],
    ['GET', '/api/leaderboard', C.green, 'Leaderboard'],
    ['GET', '/api/admin/*', C.green, 'Admin panel'],
    ['GET', '/api/teams/*', C.green, 'Team management'],
  ];

  routes.forEach(([method, path, color, label]) => {
    const m = `${color}${C.bold}${method.padEnd(6)}${C.reset}`;
    const p = `${C.white}${path.padEnd(22)}${C.reset}`;
    const l = `${C.dim}${label}${C.reset}`;
    console.log(`${C.blue}${C.bold}  ║${C.reset}    ${m} ${p} ${l}  ${C.blue}${C.bold}║${C.reset}`);
  });

  console.log(`${C.blue}${C.bold}  ║${C.reset}                                          ${C.blue}${C.bold}║${C.reset}`);
  console.log(`${C.blue}${C.bold}  ╚══════════════════════════════════════════╝${C.reset}`);
  console.log('');
  console.log(`${C.dim}  ${line}${C.reset}`);
  console.log(`${C.cyan}  → Ready to accept connections${C.reset}`);
  console.log(`${C.dim}  ${line}${C.reset}`);
  console.log('');
}

// ─── Response Logger (call in middleware after res finishes) ─────────────────

export function responseLogger() {
  return (req: any, res: any, next: () => void) => {
    const start = Date.now();

    res.on('finish', () => {
      const duration = Date.now() - start;
      const status = res.statusCode;
      const method = req.method;
      const url = req.originalUrl || req.url;

      let statusBg = C.bgGreen;
      if (status >= 500) { statusBg = C.bgRed; }
      else if (status >= 400) { statusBg = C.bgYellow; }
      else if (status >= 300) { statusBg = C.bgCyan; }

      const durationColor = duration > 1000 ? C.red : duration > 500 ? C.yellow : C.green;

      const METHOD_COLORS: Record<string, string> = {
        GET: C.green,
        POST: C.blue,
        PUT: C.yellow,
        DELETE: C.red,
        PATCH: C.magenta,
      };
      const mColor = METHOD_COLORS[method] || C.white;

      const ts = `${C.dim}${timestamp()}${C.reset}`;
      const m = `${mColor}${C.bold}${method.padEnd(7)}${C.reset}`;
      const s = `${statusBg}${C.bold}${C.white} ${status} ${C.reset}`;
      const d = `${durationColor}${C.bold}${duration}ms${C.reset}`;
      const u = `${C.white}${url}${C.reset}`;

      console.log(`${C.dim}└─${C.reset} ${ts} ${C.magenta}${C.bold} RES  ${C.reset} ${m} ${s} ${u} ${C.dim}${C.gray}→${C.reset} ${d}`);
    });

    next();
  };
}

// ─── Security Alert ─────────────────────────────────────────────────────────

export function logSecurity(message: string, ip?: string) {
  const ts = `${C.dim}${timestamp()}${C.reset}`;
  const icon = `${C.bgRed}${C.bold}${C.white} ⚠ SECURITY ${C.reset}`;
  const ipStr = ip ? `${C.gray}← ${ip}${C.reset}` : '';
  console.log(`${C.red}${C.bold}  ┌─${C.reset} ${ts} ${icon} ${C.red}${C.bold}${message}${C.reset} ${ipStr}`);
}

// ─── Activity Log (console only) ────────────────────────────────────────────

export function logActivityConsole(action: string, details?: string) {
  const ts = `${C.dim}${timestamp()}${C.reset}`;
  const icon = `${C.bgMagenta}${C.bold}${C.white} ♦ LOG ${C.reset}`;
  const act = `${C.magenta}${C.bold}${action}${C.reset}`;
  const det = details ? `${C.dim}— ${details}${C.reset}` : '';
  console.log(`${C.dim}┌─${C.reset} ${ts} ${icon} ${act} ${det}`);
}