import { pino } from 'pino'
import pinoPretty from 'pino-pretty'

import { getEnv } from './env'

export type Level = 'fatal' | 'error' | 'warn' | 'info' | 'debug' | 'trace'
export type LevelWithSilent = Level | 'silent'

interface LogFn {
  <T extends object>(obj: T, msg?: string, ...args: any[]): void
  (obj: unknown, msg?: string, ...args: any[]): void
  (msg: string, ...args: any[]): void
}

// these types are taken from `pino`
export interface Logger {
  /**
   * Set this property to the desired logging level. In order of priority, available levels are:
   *
   * - 'fatal'
   * - 'error'
   * - 'warn'
   * - 'info'
   * - 'debug'
   * - 'trace'
   *
   * The logging level is a __minimum__ level. For instance if `logger.level` is `'info'` then all `'fatal'`, `'error'`, `'warn'`,
   * and `'info'` logs will be enabled.
   *
   * You can pass `'silent'` to disable logging.
   */
  level: LevelWithSilent | string

  /**
   * Log at `'fatal'` level the given msg. If the first argument is an object, all its properties will be included in the JSON line.
   * If more args follows `msg`, these will be used to format `msg` using `util.format`.
   *
   * @typeParam T - the interface of the object being serialized. Default is object.
   * @param obj - object to be serialized
   * @param msg - the log message to write
   * @param args - format string values when `msg` is a format string
   */
  fatal: LogFn

  /**
   * Log at `'error'` level the given msg. If the first argument is an object, all its properties will be included in the JSON line.
   * If more args follows `msg`, these will be used to format `msg` using `util.format`.
   *
   * @typeParam T - the interface of the object being serialized. Default is object.
   * @param obj - object to be serialized
   * @param msg - the log message to write
   * @param args - format string values when `msg` is a format string
   */
  error: LogFn

  /**
   * Log at `'warn'` level the given msg. If the first argument is an object, all its properties will be included in the JSON line.
   * If more args follows `msg`, these will be used to format `msg` using `util.format`.
   *
   * @typeParam T - the interface of the object being serialized. Default is object.
   * @param obj - object to be serialized
   * @param msg -  the log message to write
   * @param args - format string values when `msg` is a format string
   */
  warn: LogFn

  /**
   * Log at `'info'` level the given msg. If the first argument is an object, all its properties will be included in the JSON line.
   * If more args follows `msg`, these will be used to format `msg` using `util.format`.
   *
   * @typeParam T - the interface of the object being serialized. Default is object.
   * @param obj - object to be serialized
   * @param msg - the log message to write
   * @param args - format string values when `msg` is a format string
   */
  info: LogFn

  /**
   * Log at `'debug'` level the given msg. If the first argument is an object, all its properties will be included in the JSON line.
   * If more args follows `msg`, these will be used to format `msg` using `util.format`.
   *
   * @typeParam T - the interface of the object being serialized. Default is object.
   * @param obj - object to be serialized
   * @param msg - the log message to write
   * @param args - format string values when `msg` is a format string
   */
  debug: LogFn

  /**
   * Log at `'trace'` level the given msg. If the first argument is an object, all its properties will be included in the JSON line.
   * If more args follows `msg`, these will be used to format `msg` using `util.format`.
   *
   * @typeParam T - the interface of the object being serialized. Default is object.
   * @param obj - object to be serialized
   * @param msg - the log message to write
   * @param args - format string values when `msg` is a format string
   */
  trace: LogFn

  /**
   * Noop function.
   */
  silent: LogFn
}

export const defaultLogger: Logger = pino(
  {
    level: getEnv('LOG_LEVEL', 'info')
  },
  pinoPretty({
    sync: true,
    colorize: true
  })
)