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 localDb: any;
  var db: any;
  var dbReady: boolean;
}

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

  if (globalThis.localDb === undefined) {
    globalThis.localDb = new PouchDB('$local_dyomedea$', {
      auto_compaction: true,
      revs_limit: 10,
    });
  }

  if (globalThis.db === undefined) {
    globalThis.db = new PouchDB('dyomedea', {
      auto_compaction: false,
    });
  }
  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;

  const sync = PouchDB.sync(
    'dyomedea',
    'http://admin:password@localhost:5984/dyomedea',
    {
      live: true,
      retry: true,
    }
  )
    .on('change', function (info) {
      // handle change
      console.log({ caller: 'Sync / change', info });
    })
    .on('paused', function (err) {
      // replication paused (e.g. replication up to date, user went offline)
      console.log({ caller: 'Sync / paused', err });
    })
    .on('active', function () {
      // replicate resumed (e.g. new changes replicating, user went back online)
      console.log({ caller: 'Sync / active' });
    })
    .on('denied', function (err) {
      // a document failed to replicate (e.g. due to permissions)
      console.error({ caller: 'Sync / denied', err });
    })
    .on('complete', function (info) {
      // handle complete
      console.log({ caller: 'Sync / complete', info });
    })
    .on('error', function (err) {
      // handle error
      console.error({ caller: 'Sync / error', err });
    });

  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();
};