import Collection from 'marsdb';
import LocalForageManager from 'marsdb-localforage';

// Default storage is in-memory
// Setup different storage managers
// (all documents will be save in a browser cache)
Collection.defaultStorageManager(LocalForageManager);

// Create collection wit new default storage
const users = new Collection('users');

import Collection from 'marsdb';
import LocalStorageManager from 'marsdb-localstorage';

// Set some defaults and create collection
Collection.defaultStorageManager(LocalStorageManager);
const users = new Collection('users');

// But it may be useful to create in-memory
// collection without defined defaults
// (for example to save some session state)
const session = new Collection('session', {inMemory: true});

const posts = new Collection('posts');
posts.find({author: 'Bob'})
  .project({author: 1})
  .sort(['createdAt'])
  .then(docs => {
    // do something with docs
  });

const posts = new Collection('posts');

// Get number of all comments in the DB
posts.find()
  .limit(10)
  .sortFunc((a, b) => a - b + 10)
  .filter(doc => Matsh.sqrt(doc.comment.length) > 1.5)
  .map(doc => doc.comments.length)
  .reduce((acum, val) => acum + val)
  .then(result => {
    // result is a number of all comments
    // in all found posts
  });

// Result is `undefined` because posts
// is not exists and additional processing
// is not ran (thanks to `.ifNotEmpty()`)
posts.find({author: 'not_existing_name'})
  .aggregate(docs => docs[0])
  .ifNotEmpty()
  .aggregate(user => user.name)

const posts = new Collection('posts');
const stopper = posts.find({tags: {$in: ['marsdb', 'is', 'awesome']}})
  .observe(docs => {
    // invoked on every result change
    // (on initial result too)
    stopper.stop(); // stops observing
  }).then(docs => {
    // invoked once on initial result
    // (after `observer` callback)
  });

const users = new Collection('users');
const posts = new Collection('posts');
posts.find()
  .join(doc => {
    // Return a Promise for waiting of the result.
    return users.findOne(doc.authorId).then(user => {
      doc.authorObj = user;
      // any return is ignored
    });
  })
  .join(doc => {
    // For reactive join you must invoke `observe` instead `then`
    // That's it!
    return users.findOne(doc.authorId).observe(user => {
      doc.authorObj = user;
    });
  })
  .join((doc, updated) => {
    // Also any other “join” mutations supported
    doc.another = _cached_data_by_post[doc._id];

    // Manually update a joined parameter and propagate
    // update event from current cursor to a root
    // (`observe` callback invoked)
    setTimeout(() => {
      doc.another = 'some another user';
      updated();
    }, 10);
  })
  // Or just pass join spec object for fast joining
  // (only one `find` will be produced for all posts)
  .join({ authorId: users }) // posts[i].authorId will be user object
  .observe((posts) => {
    // do something with posts with authors
    // invoked any time when posts changed
    // (and when observed joins changed too)
  })

const posts = new Collection('posts');
posts.insert({text: 'MarsDB is awesome'}).then(docId => {
  // Invoked after persisting document
})
posts.insertAll(
  {text: 'MarsDB'},
  {text: 'is'},
  {text: 'awesome'}
).then(docsIds => {
  // invoked when all documents inserted
});

const posts = new Collection('posts');
posts.update(
  {authorId: {$in: [1, 2, 3]}},
  {$set: {text: 'noop'}}
).then(result => {
  console.log(result.modified) // count of modified docs
  console.log(result.updated) // array of updated docs
  console.log(result.original) // array of original docs
});

// Upsert (insert when nothing found)
posts.update(
  {authorId: "123"},
  {$set: {text: 'noop'}},
  {upsert: true}
).then(result => {
  // { authorId: "123", text: 'noop', _id: '...' }
});

const posts = new Collection('posts');
posts.remove({authorId: {$in: [1,2,3]}})
  .then(removedDocs => {
    // do something with removed documents array
  });