import _ from 'lodash';
import PouchDB from 'pouchdb';
import uri from '../lib/ids';
import changeHandler from './change-handler';

const dbDefinitionId = uri('dbdef', {});

const currentDbDefinition = {
  _id: dbDefinitionId,
  type: dbDefinitionId,
  def: { version: '0.000001' },
};

declare global {
  var db: any;
  var dbReady: boolean;
}

export const initDb = async (params: any) => {
  console.log({ caller: 'initDb' });

  if (globalThis.db === undefined) {
    globalThis.db = new PouchDB('dyomedea', {
      auto_compaction: false,
      //    revs_limit: 10,
    });
  }
  const db = globalThis.db;
  var previousDbDefinition = {
    _id: dbDefinitionId,
    type: dbDefinitionId,
    def: { version: '0' },
  };
  try {
    previousDbDefinition = await db.get(dbDefinitionId);
  } catch (error: any) {
    if (error.status !== 404) {
      console.log(
        `Unexpected error fetching db definition: ${JSON.stringify(error)}`
      );
      return;
    }
  }

  if (previousDbDefinition.def.version < currentDbDefinition.def.version) {
    previousDbDefinition.def = currentDbDefinition.def;
    db.put(previousDbDefinition);
    // TODO: support migrations
  }
  //await await db.compact();

  globalThis.dbReady = true;

  console.log({ caller: 'initDb / before db.changes' });

  const changes = db
    .changes({ since: 'now', live: true, include_docs: false })
    .on('change', changeHandler)
    .on('complete', (info: any) => {
      console.log({ caller: 'changes / complete', info });
    })
    .on('error', (error: any) => {
      console.log({ caller: 'changes / complete', error });
    });

  // console.log({ caller: 'initDb / back from db.changes', changes });

  //  changes.cancel();
};