import { trace } from '@opentelemetry/api';

enum LogLevel {
  TRACE = 'trace',
  DEBUG = 'debug',
  INFO = 'info',
  WARN = 'warn',
  ERROR = 'error',
  FATAL = 'fatal',
  SILENT = 'silent'
}

const LOG_LEVELS = new Map([
  ['trace', 10],
  ['debug', 20],
  ['info', 30],
  ['warn', 40],
  ['error', 50],
  ['fatal', 60],
  ['silent', 1000]
]);

interface LoggerFn {
  (message: string, payload?: any): void;
}

interface Message {
  message: string;
  level?: LogLevel;
  payload?: any;
  details?: any;
}

const LOG_COLORS = new Map([
  [LogLevel.TRACE, '\x1b[45m'],
  [LogLevel.DEBUG, '\x1b[44m'],
  [LogLevel.INFO, '\x1b[42m'],
  [LogLevel.WARN, '\x1b[43m'],
  [LogLevel.ERROR, '\x1b[41m'],
  [LogLevel.FATAL, '\x1b[41m']
]);

let LOG_LEVEL = LOG_LEVELS.get(LogLevel.INFO);

if (process.env.NODE_ENV === 'development') {
  LOG_LEVEL = LOG_LEVELS.get(process.env.LOG_LEVEL_DEV ?? LogLevel.INFO);
}

if (process.env.NODE_ENV === 'production') {
  LOG_LEVEL = LOG_LEVELS.get(process.env.LOG_LEVEL ?? LogLevel.INFO);
}

const writeMsg = ({ level, message, payload }: Message) => {
  if (LOG_LEVELS.get(level) < LOG_LEVEL) {
    return;
  }

  let log: Message | string = { message };

  if (payload) {
    log.details = payload;
  }

  if (process.env.NODE_ENV === 'production') {
    log.level = level;
    log = `PZ LOG    ----${level.toUpperCase()}----    ${JSON.stringify(log)}`;
  }

  if (process.env.NODE_ENV === 'development') {
    console.log(
      '\n\n' + LOG_COLORS.get(level),
      `▼ PZ ${level.toUpperCase()}${
        message.length < 250 ? ` ━━ ${message}` : ''
      } \x1b[0m\n`,
      log,
      '\n\n'
    );
  } else {
    console.log(log);
  }
};

function createCustomSpan({ level, message, payload }: Message) {
  const tracer = trace.getTracer('pz-next-app');
  const span = tracer.startSpan('custom-operation-log');

  span.setAttributes({
    level,
    message,
    payload
  });

  span.end();
}

const createLogAndSpan = (level: LogLevel, message: string, payload?: any) => {
  const content = {
    level,
    message,
    payload: JSON.stringify(payload)
  };

  writeMsg(content);
  createCustomSpan(content);
};

const logger: Record<LogLevel, LoggerFn> = {
  trace: (message, payload) =>
    createLogAndSpan(LogLevel.TRACE, message, payload),
  debug: (message, payload) =>
    createLogAndSpan(LogLevel.DEBUG, message, payload),
  info: (message, payload) => createLogAndSpan(LogLevel.INFO, message, payload),
  warn: (message, payload) => createLogAndSpan(LogLevel.WARN, message, payload),
  error: (message, payload) =>
    createLogAndSpan(LogLevel.ERROR, message, payload),
  fatal: (message, payload) =>
    createLogAndSpan(LogLevel.FATAL, message, payload),
  silent: () => {}
};

export default logger;