import {makeAutoObservable} from 'mobx'
import {isObj, hasProp} from '../lib/type-guards'

interface LogEntry {
  id: string
  type?: string
  summary?: string
  details?: string
  ts?: number
}

let _lastTs: string
let _lastId: string
function genId(): string {
  let candidate = String(Date.now())
  if (_lastTs === candidate) {
    const id = _lastId + 'x'
    _lastId = id
    return id
  }
  _lastTs = candidate
  _lastId = candidate
  return candidate
}

export class LogModel {
  entries: LogEntry[] = []

  constructor() {
    makeAutoObservable(this, {serialize: false, hydrate: false})
  }

  serialize(): unknown {
    return {
      entries: this.entries.slice(-100),
    }
  }

  hydrate(v: unknown) {
    if (isObj(v)) {
      if (hasProp(v, 'entries') && Array.isArray(v.entries)) {
        this.entries = v.entries.filter(
          e => isObj(e) && hasProp(e, 'id') && typeof e.id === 'string',
        )
      }
    }
  }

  private add(entry: LogEntry) {
    this.entries.push(entry)
  }

  debug(summary: string, details?: any) {
    if (details && typeof details !== 'string') {
      details = JSON.stringify(details, null, 2)
    }
    console.debug(summary, details || '')
    this.add({
      id: genId(),
      type: 'debug',
      summary,
      details,
      ts: Date.now(),
    })
  }

  warn(summary: string, details?: any) {
    if (details && typeof details !== 'string') {
      details = JSON.stringify(details, null, 2)
    }
    console.warn(summary, details || '')
    this.add({
      id: genId(),
      type: 'warn',
      summary,
      details,
      ts: Date.now(),
    })
  }

  error(summary: string, details?: any) {
    if (details && typeof details !== 'string') {
      details = JSON.stringify(details, null, 2)
    }
    console.error(summary, details || '')
    this.add({
      id: genId(),
      type: 'error',
      summary,
      details,
      ts: Date.now(),
    })
  }
}