senecajs/seneca-entity-history

/* Copyright (c) 2020 voxgig and other contributors, MIT License */
/* $lab:coverage:off$ */
'use strict'

/* $lab:coverage:on$ */

const intern = {

  // NOTE: excludes data field `d`
  entver_fields: [
    'ent_id',
    'ent_rtag',
    'prev_rtag',
    'prev_ver_id',
    'c_version',
    'res_ver_id',
    'fields',
    'changed',
    'base',
    'name',
    'when',
    'who',
    'what',
    'is_finder',
    'is_restore',
  ],

  // TODO: should be an entity util
  canon(msg: any) {
    return (null == msg.zone ? '-' : msg.zone) + '/' +
      (null == msg.base ? '-' : msg.base) + '/' +
      (null == msg.name ? '-' : msg.name)
  },


  // sys/entver - entity versions, including data
  // sys/enthist - entity version metadata, excluding data
  async history(histspec: any) {
    let seneca = histspec.seneca
    let entmsg = histspec.entmsg
    let entout = histspec.entout
    let entprev = histspec.entprev
    let changed = histspec.changed
    let who = histspec.who
    let what = histspec.what

    let canon = entout.canon$({ object: true })

    // also indexed by entity id for fast lookup of current version
    let finder = await seneca
      .entity('sys/entver')
      .load$(entout.id)

    let data = entout.data$(false)

    let entver = await seneca
      .entity('sys/entver')
      .data$({
        ent_id: entout.id,
        ent_rtag: entout.rtag,
        prev_rtag: entprev ? entprev.rtag : '',
        prev_ver_id: finder ? finder.ver_id : '',
        c_version: finder ? 1 + finder.c_version : 0,
        res_ver_id: entmsg.custom$ ? entmsg.custom$.res_ver_id : undefined,
        fields: Object.keys(data),
        changed: changed,
        base: canon.base,
        name: canon.name,
        when: Date.now(),
        who,
        what,
        is_finder: false,
        is_restore: !!(entmsg.custom$ && entmsg.custom$.res_ver_id),
        d: data
      })
      .save$()


    if (finder) {
      finder = finder.data$(entver)
      finder.id = entver.ent_id
    }
    else {
      finder = entver.clone$()
      delete finder.id
      finder.id$ = entver.ent_id
    }
    finder.ver_id = entver.id
    finder.is_finder = true

    await finder.save$()
  }


}


export default intern