'use strict';

var common = require('./common'),
  utils = require('../utils'),
  toError = require('../utils').toError,
  handleCallback = require('../utils').handleCallback,
  shallowClone = utils.shallowClone,
  BulkWriteResult = common.BulkWriteResult,
  ObjectID = require('mongodb-core').BSON.ObjectID,
  Define = require('../metadata'),
  BSON = require('mongodb-core').BSON,
  Batch = common.Batch,
  mergeBatchResults = common.mergeBatchResults,
  executeOperation = require('../utils').executeOperation,
  BulkWriteError = require('./common').BulkWriteError;

var bson = new BSON([
  BSON.Binary,
  BSON.Code,
  BSON.DBRef,
  BSON.Decimal128,
  BSON.Double,
  BSON.Int32,
  BSON.Long,
  BSON.Map,
  BSON.MaxKey,
  BSON.MinKey,
  BSON.ObjectId,
  BSON.BSONRegExp,
  BSON.Symbol,
  BSON.Timestamp
]);

/**
 * Create a FindOperatorsOrdered instance (INTERNAL TYPE, do not instantiate directly)
 * @class
 * @return {FindOperatorsOrdered} a FindOperatorsOrdered instance.
 */
var FindOperatorsOrdered = function(self) {
  this.s = self.s;
};

/**
 * Add a single update document to the bulk operation
 *
 * @method
 * @param {object} doc update operations
 * @throws {MongoError}
 * @return {OrderedBulkOperation}
 */
FindOperatorsOrdered.prototype.update = function(updateDocument) {
  // Perform upsert
  var upsert = typeof this.s.currentOp.upsert === 'boolean' ? this.s.currentOp.upsert : false;

  // Establish the update command
  var document = {
    q: this.s.currentOp.selector,
    u: updateDocument,
    multi: true,
    upsert: upsert
  };

  // Clear out current Op
  this.s.currentOp = null;
  // Add the update document to the list
  return addToOperationsList(this, common.UPDATE, document);
};

/**
 * Add a single update one document to the bulk operation
 *
 * @method
 * @param {object} doc update operations
 * @throws {MongoError}
 * @return {OrderedBulkOperation}
 */
FindOperatorsOrdered.prototype.updateOne = function(updateDocument) {
  // Perform upsert
  var upsert = typeof this.s.currentOp.upsert === 'boolean' ? this.s.currentOp.upsert : false;

  // Establish the update command
  var document = {
    q: this.s.currentOp.selector,
    u: updateDocument,
    multi: false,
    upsert: upsert
  };

  // Clear out current Op
  this.s.currentOp = null;
  // Add the update document to the list
  return addToOperationsList(this, common.UPDATE, document);
};

/**
 * Add a replace one operation to the bulk operation
 *
 * @method
 * @param {object} doc the new document to replace the existing one with
 * @throws {MongoError}
 * @return {OrderedBulkOperation}
 */
FindOperatorsOrdered.prototype.replaceOne = function(updateDocument) {
  this.updateOne(updateDocument);
};

/**
 * Upsert modifier for update bulk operation
 *
 * @method
 * @throws {MongoError}
 * @return {FindOperatorsOrdered}
 */
FindOperatorsOrdered.prototype.upsert = function() {
  this.s.currentOp.upsert = true;
  return this;
};

/**
 * Add a remove one operation to the bulk operation
 *
 * @method
 * @throws {MongoError}
 * @return {OrderedBulkOperation}
 */
FindOperatorsOrdered.prototype.deleteOne = function() {
  // Establish the update command
  var document = {
    q: this.s.currentOp.selector,
    limit: 1
  };

  // Clear out current Op
  this.s.currentOp = null;
  // Add the remove document to the list
  return addToOperationsList(this, common.REMOVE, document);
};

// Backward compatibility
FindOperatorsOrdered.prototype.removeOne = FindOperatorsOrdered.prototype.deleteOne;

/**
 * Add a remove operation to the bulk operation
 *
 * @method
 * @throws {MongoError}
 * @return {OrderedBulkOperation}
 */
FindOperatorsOrdered.prototype.delete = function() {
  // Establish the update command
  var document = {
    q: this.s.currentOp.selector,
    limit: 0
  };

  // Clear out current Op
  this.s.currentOp = null;
  // Add the remove document to the list
  return addToOperationsList(this, common.REMOVE, document);
};

// Backward compatibility
FindOperatorsOrdered.prototype.remove = FindOperatorsOrdered.prototype.delete;

// Add to internal list of documents
var addToOperationsList = function(_self, docType, document) {
  // Get the bsonSize
  var bsonSize = bson.calculateObjectSize(document, {
    checkKeys: false
  });

  // Throw error if the doc is bigger than the max BSON size
  if (bsonSize >= _self.s.maxBatchSizeBytes) {
    throw toError('document is larger than the maximum size ' + _self.s.maxBatchSizeBytes);
  }

  // Create a new batch object if we don't have a current one
  if (_self.s.currentBatch == null) _self.s.currentBatch = new Batch(docType, _self.s.currentIndex);

  // Check if we need to create a new batch
  if (
    _self.s.currentBatchSize + 1 >= _self.s.maxWriteBatchSize ||
    _self.s.currentBatchSizeBytes + _self.s.currentBatchSizeBytes >= _self.s.maxBatchSizeBytes ||
    _self.s.currentBatch.batchType !== docType
  ) {
    // Save the batch to the execution stack
    _self.s.batches.push(_self.s.currentBatch);

    // Create a new batch
    _self.s.currentBatch = new Batch(docType, _self.s.currentIndex);

    // Reset the current size trackers
    _self.s.currentBatchSize = 0;
    _self.s.currentBatchSizeBytes = 0;
  } else {
    // Update current batch size
    _self.s.currentBatchSize = _self.s.currentBatchSize + 1;
    _self.s.currentBatchSizeBytes = _self.s.currentBatchSizeBytes + bsonSize;
  }

  if (docType === common.INSERT) {
    _self.s.bulkResult.insertedIds.push({ index: _self.s.currentIndex, _id: document._id });
  }

  // We have an array of documents
  if (Array.isArray(document)) {
    throw toError('operation passed in cannot be an Array');
  } else {
    _self.s.currentBatch.originalIndexes.push(_self.s.currentIndex);
    _self.s.currentBatch.operations.push(document);
    _self.s.currentBatchSizeBytes = _self.s.currentBatchSizeBytes + bsonSize;
    _self.s.currentIndex = _self.s.currentIndex + 1;
  }

  // Return self
  return _self;
};

/**
 * Create a new OrderedBulkOperation instance (INTERNAL TYPE, do not instantiate directly)
 * @class
 * @property {number} length Get the number of operations in the bulk.
 * @return {OrderedBulkOperation} a OrderedBulkOperation instance.
 */
function OrderedBulkOperation(topology, collection, options) {
  options = options == null ? {} : options;
  // TODO Bring from driver information in isMaster
  var executed = false;

  // Current item
  var currentOp = null;

  // Handle to the bson serializer, used to calculate running sizes
  var bson = topology.bson;

  // Namespace for the operation
  var namespace = collection.collectionName;

  // Set max byte size
  var maxBatchSizeBytes =
    topology.isMasterDoc && topology.isMasterDoc.maxBsonObjectSize
      ? topology.isMasterDoc.maxBsonObjectSize
      : 1024 * 1025 * 16;
  var maxWriteBatchSize =
    topology.isMasterDoc && topology.isMasterDoc.maxWriteBatchSize
      ? topology.isMasterDoc.maxWriteBatchSize
      : 1000;

  // Get the write concern
  var writeConcern = common.writeConcern(shallowClone(options), collection, options);

  // Get the promiseLibrary
  var promiseLibrary = options.promiseLibrary || Promise;

  // Final results
  var bulkResult = {
    ok: 1,
    writeErrors: [],
    writeConcernErrors: [],
    insertedIds: [],
    nInserted: 0,
    nUpserted: 0,
    nMatched: 0,
    nModified: 0,
    nRemoved: 0,
    upserted: []
  };

  // Internal state
  this.s = {
    // Final result
    bulkResult: bulkResult,
    // Current batch state
    currentBatch: null,
    currentIndex: 0,
    currentBatchSize: 0,
    currentBatchSizeBytes: 0,
    batches: [],
    // Write concern
    writeConcern: writeConcern,
    // Max batch size options
    maxBatchSizeBytes: maxBatchSizeBytes,
    maxWriteBatchSize: maxWriteBatchSize,
    // Namespace
    namespace: namespace,
    // BSON
    bson: bson,
    // Topology
    topology: topology,
    // Options
    options: options,
    // Current operation
    currentOp: currentOp,
    // Executed
    executed: executed,
    // Collection
    collection: collection,
    // Promise Library
    promiseLibrary: promiseLibrary,
    // Fundamental error
    err: null,
    // Bypass validation
    bypassDocumentValidation:
      typeof options.bypassDocumentValidation === 'boolean'
        ? options.bypassDocumentValidation
        : false,
    // check keys
    checkKeys: typeof options.checkKeys === 'boolean' ? options.checkKeys : true
  };
}

var define = (OrderedBulkOperation.define = new Define(
  'OrderedBulkOperation',
  OrderedBulkOperation,
  false
));

OrderedBulkOperation.prototype.raw = function(op) {
  var key = Object.keys(op)[0];

  // Set up the force server object id
  var forceServerObjectId =
    typeof this.s.options.forceServerObjectId === 'boolean'
      ? this.s.options.forceServerObjectId
      : this.s.collection.s.db.options.forceServerObjectId;

  // Update operations
  if (
    (op.updateOne && op.updateOne.q) ||
    (op.updateMany && op.updateMany.q) ||
    (op.replaceOne && op.replaceOne.q)
  ) {
    op[key].multi = op.updateOne || op.replaceOne ? false : true;
    return addToOperationsList(this, common.UPDATE, op[key]);
  }

  // Crud spec update format
  if (op.updateOne || op.updateMany || op.replaceOne) {
    var multi = op.updateOne || op.replaceOne ? false : true;
    var operation = { q: op[key].filter, u: op[key].update || op[key].replacement, multi: multi };
    operation.upsert = op[key].upsert ? true : false;
    if (op.collation) operation.collation = op.collation;
    if (op[key].arrayFilters) operation.arrayFilters = op[key].arrayFilters;
    return addToOperationsList(this, common.UPDATE, operation);
  }

  // Remove operations
  if (
    op.removeOne ||
    op.removeMany ||
    (op.deleteOne && op.deleteOne.q) ||
    (op.deleteMany && op.deleteMany.q)
  ) {
    op[key].limit = op.removeOne ? 1 : 0;
    return addToOperationsList(this, common.REMOVE, op[key]);
  }

  // Crud spec delete operations, less efficient
  if (op.deleteOne || op.deleteMany) {
    var limit = op.deleteOne ? 1 : 0;
    operation = { q: op[key].filter, limit: limit };
    if (op.collation) operation.collation = op.collation;
    return addToOperationsList(this, common.REMOVE, operation);
  }

  // Insert operations
  if (op.insertOne && op.insertOne.document == null) {
    if (forceServerObjectId !== true && op.insertOne._id == null) op.insertOne._id = new ObjectID();
    return addToOperationsList(this, common.INSERT, op.insertOne);
  } else if (op.insertOne && op.insertOne.document) {
    if (forceServerObjectId !== true && op.insertOne.document._id == null)
      op.insertOne.document._id = new ObjectID();
    return addToOperationsList(this, common.INSERT, op.insertOne.document);
  }

  if (op.insertMany) {
    for (var i = 0; i < op.insertMany.length; i++) {
      if (forceServerObjectId !== true && op.insertMany[i]._id == null)
        op.insertMany[i]._id = new ObjectID();
      addToOperationsList(this, common.INSERT, op.insertMany[i]);
    }

    return;
  }

  // No valid type of operation
  throw toError(
    'bulkWrite only supports insertOne, insertMany, updateOne, updateMany, removeOne, removeMany, deleteOne, deleteMany'
  );
};

/**
 * Add a single insert document to the bulk operation
 *
 * @param {object} doc the document to insert
 * @throws {MongoError}
 * @return {OrderedBulkOperation}
 */
OrderedBulkOperation.prototype.insert = function(document) {
  if (this.s.collection.s.db.options.forceServerObjectId !== true && document._id == null)
    document._id = new ObjectID();
  return addToOperationsList(this, common.INSERT, document);
};

/**
 * Initiate a find operation for an update/updateOne/remove/removeOne/replaceOne
 *
 * @method
 * @param {object} selector The selector for the bulk operation.
 * @throws {MongoError}
 * @return {FindOperatorsOrdered}
 */
OrderedBulkOperation.prototype.find = function(selector) {
  if (!selector) {
    throw toError('Bulk find operation must specify a selector');
  }

  // Save a current selector
  this.s.currentOp = {
    selector: selector
  };

  return new FindOperatorsOrdered(this);
};

Object.defineProperty(OrderedBulkOperation.prototype, 'length', {
  enumerable: true,
  get: function() {
    return this.s.currentIndex;
  }
});

//
// Execute next write command in a chain
var executeCommands = function(self, options, callback) {
  if (self.s.batches.length === 0) {
    return handleCallback(callback, null, new BulkWriteResult(self.s.bulkResult));
  }

  // Ordered execution of the command
  var batch = self.s.batches.shift();

  var resultHandler = function(err, result) {
    // Error is a driver related error not a bulk op error, terminate
    if ((err && err.driver) || (err && err.message)) {
      return handleCallback(callback, err);
    }

    // If we have and error
    if (err) err.ok = 0;
    // Merge the results together
    var mergeResult = mergeBatchResults(true, batch, self.s.bulkResult, err, result);
    const writeResult = new BulkWriteResult(self.s.bulkResult);
    if (mergeResult != null) {
      return handleCallback(callback, null, writeResult);
    }

    // If we are ordered and have errors and they are
    // not all replication errors terminate the operation
    if (self.s.bulkResult.writeErrors.length > 0) {
      if (self.s.bulkResult.writeErrors.length === 1) {
        return handleCallback(
          callback,
          new BulkWriteError(toError(self.s.bulkResult.writeErrors[0]), writeResult),
          null
        );
      }

      return handleCallback(
        callback,
        new BulkWriteError(
          toError({
            message: 'write operation failed',
            code: self.s.bulkResult.writeErrors[0].code,
            writeErrors: self.s.bulkResult.writeErrors
          }),
          writeResult
        ),
        null
      );
    } else if (writeResult.getWriteConcernError()) {
      return handleCallback(
        callback,
        new BulkWriteError(toError(writeResult.getWriteConcernError()), writeResult),
        null
      );
    }

    // Execute the next command in line
    executeCommands(self, options, callback);
  };

  var finalOptions = Object.assign({ ordered: true }, options);
  if (self.s.writeConcern != null) {
    finalOptions.writeConcern = self.s.writeConcern;
  }

  // Set an operationIf if provided
  if (self.operationId) {
    resultHandler.operationId = self.operationId;
  }

  // Serialize functions
  if (self.s.options.serializeFunctions) {
    finalOptions.serializeFunctions = true;
  }

  // Ignore undefined
  if (self.s.options.ignoreUndefined) {
    finalOptions.ignoreUndefined = true;
  }

  // Is the bypassDocumentValidation options specific
  if (self.s.bypassDocumentValidation === true) {
    finalOptions.bypassDocumentValidation = true;
  }

  // Is the checkKeys option disabled
  if (self.s.checkKeys === false) {
    finalOptions.checkKeys = false;
  }

  try {
    if (batch.batchType === common.INSERT) {
      self.s.topology.insert(
        self.s.collection.namespace,
        batch.operations,
        finalOptions,
        resultHandler
      );
    } else if (batch.batchType === common.UPDATE) {
      self.s.topology.update(
        self.s.collection.namespace,
        batch.operations,
        finalOptions,
        resultHandler
      );
    } else if (batch.batchType === common.REMOVE) {
      self.s.topology.remove(
        self.s.collection.namespace,
        batch.operations,
        finalOptions,
        resultHandler
      );
    }
  } catch (err) {
    // Force top level error
    err.ok = 0;
    // Merge top level error and return
    handleCallback(callback, null, mergeBatchResults(false, batch, self.s.bulkResult, err, null));
  }
};

/**
 * The callback format for results
 * @callback OrderedBulkOperation~resultCallback
 * @param {MongoError} error An error instance representing the error during the execution.
 * @param {BulkWriteResult} result The bulk write result.
 */

/**
 * Execute the ordered bulk operation
 *
 * @method
 * @param {object} [options=null] Optional settings.
 * @param {(number|string)} [options.w=null] The write concern.
 * @param {number} [options.wtimeout=null] The write concern timeout.
 * @param {boolean} [options.j=false] Specify a journal write concern.
 * @param {boolean} [options.fsync=false] Specify a file sync write concern.
 * @param {OrderedBulkOperation~resultCallback} [callback] The result callback
 * @throws {MongoError}
 * @return {Promise} returns Promise if no callback passed
 */
OrderedBulkOperation.prototype.execute = function(_writeConcern, options, callback) {
  if (typeof options === 'function') (callback = options), (options = {});
  options = options || {};

  if (this.s.executed) {
    var executedError = toError('batch cannot be re-executed');
    return typeof callback === 'function'
      ? callback(executedError, null)
      : this.s.promiseLibrary.reject(executedError);
  }

  if (typeof _writeConcern === 'function') {
    callback = _writeConcern;
  } else if (_writeConcern && typeof _writeConcern === 'object') {
    this.s.writeConcern = _writeConcern;
  }

  // If we have current batch
  if (this.s.currentBatch) this.s.batches.push(this.s.currentBatch);

  // If we have no operations in the bulk raise an error
  if (this.s.batches.length === 0) {
    var emptyBatchError = toError('Invalid Operation, no operations specified');
    return typeof callback === 'function'
      ? callback(emptyBatchError, null)
      : this.s.promiseLibrary.reject(emptyBatchError);
  }

  return executeOperation(this.s.topology, executeCommands, [this, options, callback]);
};

define.classMethod('execute', { callback: true, promise: false });

/**
 * Returns an unordered batch object
 * @ignore
 */
var initializeOrderedBulkOp = function(topology, collection, options) {
  return new OrderedBulkOperation(topology, collection, options);
};

initializeOrderedBulkOp.OrderedBulkOperation = OrderedBulkOperation;
module.exports = initializeOrderedBulkOp;
module.exports.Bulk = OrderedBulkOperation;