/*!
 * Module dependencies.
 */

var utils = require('../utils');

var MongooseBuffer = require('../types').Buffer;
var SchemaType = require('../schematype');

var Binary = MongooseBuffer.Binary;
var CastError = SchemaType.CastError;
var Document;

/**
 * Buffer SchemaType constructor
 *
 * @param {String} key
 * @param {SchemaType} cast
 * @inherits SchemaType
 * @api private
 */

function SchemaBuffer (key, options) {
  SchemaType.call(this, key, options, 'Buffer');
}

/**
 * This schema type's name, to defend against minifiers that mangle
 * function names.
 *
 * @api private
 */
SchemaBuffer.schemaName = 'Buffer';

/*!
 * Inherits from SchemaType.
 */
SchemaBuffer.prototype = Object.create( SchemaType.prototype );
SchemaBuffer.prototype.constructor = SchemaBuffer;

/**
 * Check required
 *
 * @api private
 */

SchemaBuffer.prototype.checkRequired = function (value, doc) {
  if (SchemaType._isRef(this, value, doc, true)) {
    return null != value;
  } else {
    return !!(value && value.length);
  }
};

/**
 * Casts contents
 *
 * @param {Object} value
 * @param {Document} doc document that triggers the casting
 * @param {Boolean} init
 * @api private
 */

SchemaBuffer.prototype.cast = function (value, doc, init) {
  var ret;
  if (SchemaType._isRef(this, value, doc, init)) {
    // wait! we may need to cast this to a document

    if (null == value) {
      return value;
    }

    // lazy load
    Document || (Document = require('./../document'));

    if (value instanceof Document) {
      value.$__.wasPopulated = true;
      return value;
    }

    // setting a populated path
    if (Buffer.isBuffer(value)) {
      return value;
    } else if (!utils.isObject(value)) {
      throw new CastError('buffer', value, this.path);
    }

    // Handle the case where user directly sets a populated
    // path to a plain object; cast to the Model used in
    // the population query.
    var path = doc.$__fullPath(this.path);
    var owner = doc.ownerDocument ? doc.ownerDocument() : doc;
    var pop = owner.populated(path, true);
    ret = new pop.options.model(value);
    ret.$__.wasPopulated = true;
    return ret;
  }

  // documents
  if (value && value._id) {
    value = value._id;
  }

  if (value && value.isMongooseBuffer) {
    return value;
  }

  if (Buffer.isBuffer(value)) {
    if (!value || !value.isMongooseBuffer) {
      value = new MongooseBuffer(value, [this.path, doc]);
    }

    return value;
  } else if (value instanceof Binary) {
    ret = new MongooseBuffer(value.value(true), [this.path, doc]);
    if (typeof value.sub_type !== 'number') {
      throw new CastError('buffer', value, this.path);
    }
    ret._subtype = value.sub_type;
    return ret;
  }

  if (null === value) return value;

  var type = typeof value;
  if ('string' == type || 'number' == type || Array.isArray(value)) {
    ret = new MongooseBuffer(value, [this.path, doc]);
    return ret;
  }

  throw new CastError('buffer', value, this.path);
};

/*!
 * ignore
 */
function handleSingle (val) {
  return this.castForQuery(val);
}

function handleArray (val) {
  var self = this;
  if (!Array.isArray(val)) {
    return [this.castForQuery(val)];
  }
  return val.map( function (m) {
    return self.castForQuery(m);
  });
}

SchemaBuffer.prototype.$conditionalHandlers =
  utils.options(SchemaType.prototype.$conditionalHandlers, {
    '$gt' : handleSingle,
    '$gte': handleSingle,
    '$in' : handleArray,
    '$lt' : handleSingle,
    '$lte': handleSingle,
    '$ne' : handleSingle,
    '$nin': handleArray
  });

/**
 * Casts contents for queries.
 *
 * @param {String} $conditional
 * @param {any} [value]
 * @api private
 */

SchemaBuffer.prototype.castForQuery = function ($conditional, val) {
  var handler;
  if (arguments.length === 2) {
    handler = this.$conditionalHandlers[$conditional];
    if (!handler)
      throw new Error("Can't use " + $conditional + " with Buffer.");
    return handler.call(this, val);
  } else {
    val = $conditional;
    return this.cast(val).toObject();
  }
};

/*!
 * Module exports.
 */

module.exports = SchemaBuffer;