var buildSearchMethod = require('./buildSearchMethod.js');
var deprecate = require('./deprecate.js');
var deprecatedMessage = require('./deprecatedMessage.js');

module.exports = IndexCore;

/*
* Index class constructor.
* You should not use this method directly but use initIndex() function
*/
function IndexCore(algoliasearch, indexName) {
  this.indexName = indexName;
  this.as = algoliasearch;
  this.typeAheadArgs = null;
  this.typeAheadValueOption = null;

  // make sure every index instance has it's own cache
  this.cache = {};
}

/*
* Clear all queries in cache
*/
IndexCore.prototype.clearCache = function() {
  this.cache = {};
};

/*
* Search inside the index using XMLHttpRequest request (Using a POST query to
* minimize number of OPTIONS queries: Cross-Origin Resource Sharing).
*
* @param {string} [query] the full text query
* @param {object} [args] (optional) if set, contains an object with query parameters:
* - page: (integer) Pagination parameter used to select the page to retrieve.
*                   Page is zero-based and defaults to 0. Thus,
*                   to retrieve the 10th page you need to set page=9
* - hitsPerPage: (integer) Pagination parameter used to select the number of hits per page. Defaults to 20.
* - attributesToRetrieve: a string that contains the list of object attributes
* you want to retrieve (let you minimize the answer size).
*   Attributes are separated with a comma (for example "name,address").
*   You can also use an array (for example ["name","address"]).
*   By default, all attributes are retrieved. You can also use '*' to retrieve all
*   values when an attributesToRetrieve setting is specified for your index.
* - attributesToHighlight: a string that contains the list of attributes you
*   want to highlight according to the query.
*   Attributes are separated by a comma. You can also use an array (for example ["name","address"]).
*   If an attribute has no match for the query, the raw value is returned.
*   By default all indexed text attributes are highlighted.
*   You can use `*` if you want to highlight all textual attributes.
*   Numerical attributes are not highlighted.
*   A matchLevel is returned for each highlighted attribute and can contain:
*      - full: if all the query terms were found in the attribute,
*      - partial: if only some of the query terms were found,
*      - none: if none of the query terms were found.
* - attributesToSnippet: a string that contains the list of attributes to snippet alongside
* the number of words to return (syntax is `attributeName:nbWords`).
*    Attributes are separated by a comma (Example: attributesToSnippet=name:10,content:10).
*    You can also use an array (Example: attributesToSnippet: ['name:10','content:10']).
*    By default no snippet is computed.
* - minWordSizefor1Typo: the minimum number of characters in a query word to accept one typo in this word.
* Defaults to 3.
* - minWordSizefor2Typos: the minimum number of characters in a query word
* to accept two typos in this word. Defaults to 7.
* - getRankingInfo: if set to 1, the result hits will contain ranking
* information in _rankingInfo attribute.
* - aroundLatLng: search for entries around a given
* latitude/longitude (specified as two floats separated by a comma).
*   For example aroundLatLng=47.316669,5.016670).
*   You can specify the maximum distance in meters with the aroundRadius parameter (in meters)
*   and the precision for ranking with aroundPrecision
*   (for example if you set aroundPrecision=100, two objects that are distant of
*   less than 100m will be considered as identical for "geo" ranking parameter).
*   At indexing, you should specify geoloc of an object with the _geoloc attribute
*   (in the form {"_geoloc":{"lat":48.853409, "lng":2.348800}})
* - insideBoundingBox: search entries inside a given area defined by the two extreme points
* of a rectangle (defined by 4 floats: p1Lat,p1Lng,p2Lat,p2Lng).
*   For example insideBoundingBox=47.3165,4.9665,47.3424,5.0201).
*   At indexing, you should specify geoloc of an object with the _geoloc attribute
*   (in the form {"_geoloc":{"lat":48.853409, "lng":2.348800}})
* - numericFilters: a string that contains the list of numeric filters you want to
* apply separated by a comma.
*   The syntax of one filter is `attributeName` followed by `operand` followed by `value`.
*   Supported operands are `<`, `<=`, `=`, `>` and `>=`.
*   You can have multiple conditions on one attribute like for example numericFilters=price>100,price<1000.
*   You can also use an array (for example numericFilters: ["price>100","price<1000"]).
* - tagFilters: filter the query by a set of tags. You can AND tags by separating them by commas.
*   To OR tags, you must add parentheses. For example, tags=tag1,(tag2,tag3) means tag1 AND (tag2 OR tag3).
*   You can also use an array, for example tagFilters: ["tag1",["tag2","tag3"]]
*   means tag1 AND (tag2 OR tag3).
*   At indexing, tags should be added in the _tags** attribute
*   of objects (for example {"_tags":["tag1","tag2"]}).
* - facetFilters: filter the query by a list of facets.
*   Facets are separated by commas and each facet is encoded as `attributeName:value`.
*   For example: `facetFilters=category:Book,author:John%20Doe`.
*   You can also use an array (for example `["category:Book","author:John%20Doe"]`).
* - facets: List of object attributes that you want to use for faceting.
*   Comma separated list: `"category,author"` or array `['category','author']`
*   Only attributes that have been added in **attributesForFaceting** index setting
*   can be used in this parameter.
*   You can also use `*` to perform faceting on all attributes specified in **attributesForFaceting**.
* - queryType: select how the query words are interpreted, it can be one of the following value:
*    - prefixAll: all query words are interpreted as prefixes,
*    - prefixLast: only the last word is interpreted as a prefix (default behavior),
*    - prefixNone: no query word is interpreted as a prefix. This option is not recommended.
* - optionalWords: a string that contains the list of words that should
* be considered as optional when found in the query.
*   Comma separated and array are accepted.
* - distinct: If set to 1, enable the distinct feature (disabled by default)
* if the attributeForDistinct index setting is set.
*   This feature is similar to the SQL "distinct" keyword: when enabled
*   in a query with the distinct=1 parameter,
*   all hits containing a duplicate value for the attributeForDistinct attribute are removed from results.
*   For example, if the chosen attribute is show_name and several hits have
*   the same value for show_name, then only the best
*   one is kept and others are removed.
* - restrictSearchableAttributes: List of attributes you want to use for
* textual search (must be a subset of the attributesToIndex index setting)
* either comma separated or as an array
* @param {function} [callback] the result callback called with two arguments:
*  error: null or Error('message'). If false, the content contains the error.
*  content: the server answer that contains the list of results.
*/
IndexCore.prototype.search = buildSearchMethod('query');

/*
* -- BETA --
* Search a record similar to the query inside the index using XMLHttpRequest request (Using a POST query to
* minimize number of OPTIONS queries: Cross-Origin Resource Sharing).
*
* @param {string} [query] the similar query
* @param {object} [args] (optional) if set, contains an object with query parameters.
*   All search parameters are supported (see search function), restrictSearchableAttributes and facetFilters
*   are the two most useful to restrict the similar results and get more relevant content
*/
IndexCore.prototype.similarSearch = buildSearchMethod('similarQuery');

/*
* Browse index content. The response content will have a `cursor` property that you can use
* to browse subsequent pages for this query. Use `index.browseFrom(cursor)` when you want.
*
* @param {string} query - The full text query
* @param {Object} [queryParameters] - Any search query parameter
* @param {Function} [callback] - The result callback called with two arguments
*   error: null or Error('message')
*   content: the server answer with the browse result
* @return {Promise|undefined} Returns a promise if no callback given
* @example
* index.browse('cool songs', {
*   tagFilters: 'public,comments',
*   hitsPerPage: 500
* }, callback);
* @see {@link https://www.algolia.com/doc/rest_api#Browse|Algolia REST API Documentation}
*/
IndexCore.prototype.browse = function(query, queryParameters, callback) {
  var merge = require('./merge.js');

  var indexObj = this;

  var page;
  var hitsPerPage;

  // we check variadic calls that are not the one defined
  // .browse()/.browse(fn)
  // => page = 0
  if (arguments.length === 0 || arguments.length === 1 && typeof arguments[0] === 'function') {
    page = 0;
    callback = arguments[0];
    query = undefined;
  } else if (typeof arguments[0] === 'number') {
    // .browse(2)/.browse(2, 10)/.browse(2, fn)/.browse(2, 10, fn)
    page = arguments[0];
    if (typeof arguments[1] === 'number') {
      hitsPerPage = arguments[1];
    } else if (typeof arguments[1] === 'function') {
      callback = arguments[1];
      hitsPerPage = undefined;
    }
    query = undefined;
    queryParameters = undefined;
  } else if (typeof arguments[0] === 'object') {
    // .browse(queryParameters)/.browse(queryParameters, cb)
    if (typeof arguments[1] === 'function') {
      callback = arguments[1];
    }
    queryParameters = arguments[0];
    query = undefined;
  } else if (typeof arguments[0] === 'string' && typeof arguments[1] === 'function') {
    // .browse(query, cb)
    callback = arguments[1];
    queryParameters = undefined;
  }

  // otherwise it's a .browse(query)/.browse(query, queryParameters)/.browse(query, queryParameters, cb)

  // get search query parameters combining various possible calls
  // to .browse();
  queryParameters = merge({}, queryParameters || {}, {
    page: page,
    hitsPerPage: hitsPerPage,
    query: query
  });

  var params = this.as._getSearchParams(queryParameters, '');

  return this.as._jsonRequest({
    method: 'POST',
    url: '/1/indexes/' + encodeURIComponent(indexObj.indexName) + '/browse',
    body: {params: params},
    hostType: 'read',
    callback: callback
  });
};

/*
* Continue browsing from a previous position (cursor), obtained via a call to `.browse()`.
*
* @param {string} query - The full text query
* @param {Object} [queryParameters] - Any search query parameter
* @param {Function} [callback] - The result callback called with two arguments
*   error: null or Error('message')
*   content: the server answer with the browse result
* @return {Promise|undefined} Returns a promise if no callback given
* @example
* index.browseFrom('14lkfsakl32', callback);
* @see {@link https://www.algolia.com/doc/rest_api#Browse|Algolia REST API Documentation}
*/
IndexCore.prototype.browseFrom = function(cursor, callback) {
  return this.as._jsonRequest({
    method: 'POST',
    url: '/1/indexes/' + encodeURIComponent(this.indexName) + '/browse',
    body: {cursor: cursor},
    hostType: 'read',
    callback: callback
  });
};

/*
* Search for facet values
* https://www.algolia.com/doc/rest-api/search#search-for-facet-values
*
* @param {string} params.facetName Facet name, name of the attribute to search for values in.
* Must be declared as a facet
* @param {string} params.facetQuery Query for the facet search
* @param {string} [params.*] Any search parameter of Algolia,
* see https://www.algolia.com/doc/api-client/javascript/search#search-parameters
* Pagination is not supported. The page and hitsPerPage parameters will be ignored.
* @param callback (optional)
*/
IndexCore.prototype.searchForFacetValues = function(params, callback) {
  var clone = require('./clone.js');
  var omit = require('./omit.js');
  var usage = 'Usage: index.searchForFacetValues({facetName, facetQuery, ...params}[, callback])';

  if (params.facetName === undefined || params.facetQuery === undefined) {
    throw new Error(usage);
  }

  var facetName = params.facetName;
  var filteredParams = omit(clone(params), function(keyName) {
    return keyName === 'facetName';
  });
  var searchParameters = this.as._getSearchParams(filteredParams, '');

  return this.as._jsonRequest({
    method: 'POST',
    url: '/1/indexes/' +
      encodeURIComponent(this.indexName) + '/facets/' + encodeURIComponent(facetName) + '/query',
    hostType: 'read',
    body: {params: searchParameters},
    callback: callback
  });
};

IndexCore.prototype.searchFacet = deprecate(function(params, callback) {
  return this.searchForFacetValues(params, callback);
}, deprecatedMessage(
  'index.searchFacet(params[, callback])',
  'index.searchForFacetValues(params[, callback])'
));

IndexCore.prototype._search = function(params, url, callback, additionalUA) {
  return this.as._jsonRequest({
    cache: this.cache,
    method: 'POST',
    url: url || '/1/indexes/' + encodeURIComponent(this.indexName) + '/query',
    body: {params: params},
    hostType: 'read',
    fallback: {
      method: 'GET',
      url: '/1/indexes/' + encodeURIComponent(this.indexName),
      body: {params: params}
    },
    callback: callback,
    additionalUA: additionalUA
  });
};

/*
* Get an object from this index
*
* @param objectID the unique identifier of the object to retrieve
* @param attrs (optional) if set, contains the array of attribute names to retrieve
* @param callback (optional) the result callback called with two arguments
*  error: null or Error('message')
*  content: the object to retrieve or the error message if a failure occured
*/
IndexCore.prototype.getObject = function(objectID, attrs, callback) {
  var indexObj = this;

  if (arguments.length === 1 || typeof attrs === 'function') {
    callback = attrs;
    attrs = undefined;
  }

  var params = '';
  if (attrs !== undefined) {
    params = '?attributes=';
    for (var i = 0; i < attrs.length; ++i) {
      if (i !== 0) {
        params += ',';
      }
      params += attrs[i];
    }
  }

  return this.as._jsonRequest({
    method: 'GET',
    url: '/1/indexes/' + encodeURIComponent(indexObj.indexName) + '/' + encodeURIComponent(objectID) + params,
    hostType: 'read',
    callback: callback
  });
};

/*
* Get several objects from this index
*
* @param objectIDs the array of unique identifier of objects to retrieve
*/
IndexCore.prototype.getObjects = function(objectIDs, attributesToRetrieve, callback) {
  var isArray = require('isarray');
  var map = require('./map.js');

  var usage = 'Usage: index.getObjects(arrayOfObjectIDs[, callback])';

  if (!isArray(objectIDs)) {
    throw new Error(usage);
  }

  var indexObj = this;

  if (arguments.length === 1 || typeof attributesToRetrieve === 'function') {
    callback = attributesToRetrieve;
    attributesToRetrieve = undefined;
  }

  var body = {
    requests: map(objectIDs, function prepareRequest(objectID) {
      var request = {
        indexName: indexObj.indexName,
        objectID: objectID
      };

      if (attributesToRetrieve) {
        request.attributesToRetrieve = attributesToRetrieve.join(',');
      }

      return request;
    })
  };

  return this.as._jsonRequest({
    method: 'POST',
    url: '/1/indexes/*/objects',
    hostType: 'read',
    body: body,
    callback: callback
  });
};

IndexCore.prototype.as = null;
IndexCore.prototype.indexName = null;
IndexCore.prototype.typeAheadArgs = null;
IndexCore.prototype.typeAheadValueOption = null;