import fs from 'fs';
import path from 'path';
import winston from 'winston';
import DailyRotateFile from 'winston-daily-rotate-file';
import { getAgentDir } from '../../utils/paths';
import { sanitizeObject } from '../../utils/sensitiveDataMasking';

const LOG_RETENTION = '30d';
const LOG_MAX_SIZE = '50m';

const agentDir = getAgentDir();

if (!fs.existsSync(agentDir)) {
  try {
    fs.mkdirSync(agentDir, { recursive: true });
  } catch (e) {
    console.error('Failed to create agent directory for API logs', e);
  }
}

const fileFormat = winston.format.combine(
  winston.format.timestamp(),
  winston.format.printf(({ timestamp, level, message, ...meta }) => {
    const logEntry = {
      timestamp,
      level,
      message,
      ...meta,
    };
    return JSON.stringify(logEntry);
  }),
);

const consoleFormat = winston.format.combine(
  winston.format.colorize({ all: true }),
  winston.format.printf(({ timestamp, level, message, ...meta }) => {
    const logEntry = {
      timestamp,
      level,
      message,
      ...meta,
    };
    return JSON.stringify(logEntry);
  }),
);

const rotateTransport = new DailyRotateFile({
  filename: path.join(agentDir, 'api-%DATE%.log'),
  datePattern: 'YYYY-MM-DD-HH',
  maxSize: LOG_MAX_SIZE,
  maxFiles: LOG_RETENTION,
  zippedArchive: false,
  auditFile: path.join(agentDir, '.api-log-audit.json'),
  level: 'debug',
  format: fileFormat,
});

rotateTransport.on('error', (error) => {
  console.error('DailyRotateFile API transport error', error);
});

const consoleTransport = new winston.transports.Console({
  level: 'debug',
  format: consoleFormat,
});

consoleTransport.on('error', (error) => {
  console.error('Console API transport error', error);
});

export const apiLogger = winston.createLogger({
  level: 'debug',
  transports: [consoleTransport, rotateTransport],
  exitOnError: false,
});

/**
 * Safely serialize a value for API logging.
 * Truncates very large bodies to avoid excessive log sizes.
 */
export function safeApiLogValue(value: unknown, maxLength = 50_000): unknown {
  const sanitized = sanitizeObject(value);

  if (typeof sanitized === 'string' && sanitized.length > maxLength) {
    return sanitized.substring(0, maxLength) + `... [truncated ${sanitized.length - maxLength} chars]`;
  }

  const stringified = JSON.stringify(sanitized);
  if (stringified.length > maxLength) {
    return stringified.substring(0, maxLength) + `... [truncated ${stringified.length - maxLength} chars]`;
  }

  return sanitized;
}