/*

YUI 3.10.3 (build 2fb5187)

Copyright 2013 Yahoo! Inc. All rights reserved.

Licensed under the BSD License.

http://yuilibrary.com/license/

*/

YUI.add('dataschema-text', function (Y, NAME) {

/**

 * Provides a DataSchema implementation which can be used to work with

 * delimited text data.

 *

 * @module dataschema

 * @submodule dataschema-text

 */

/**

Provides a DataSchema implementation which can be used to work with

delimited text data.

See the `apply` method for usage.

@class DataSchema.Text

@extends DataSchema.Base

@static

**/

var Lang = Y.Lang,

    isString = Lang.isString,

    isUndef  = Lang.isUndefined,

    SchemaText = {

        ////////////////////////////////////////////////////////////////////////

        //

        // DataSchema.Text static methods

        //

        ////////////////////////////////////////////////////////////////////////

        /**

        Applies a schema to a string of delimited data, returning a normalized

        object with results in the `results` property. The `meta` property of

        the response object is present for consistency, but is assigned an

        empty object.  If the input data is absent or not a string, an `error`

        property will be added.

        Use _schema.resultDelimiter_ and _schema.fieldDelimiter_ to instruct

        `apply` how to split up the string into an array of data arrays for

        processing.

        Use _schema.resultFields_ to specify the keys in the generated result

        objects in `response.results`. The key:value pairs will be assigned

        in the order of the _schema.resultFields_ array, assuming the values

        in the data records are defined in the same order.

        _schema.resultFields_ field identifiers are objects with the following

        properties:

          * `key`   : <strong>(required)</strong> The property name you want

                the data value assigned to in the result object (String)

          * `parser`: A function or the name of a function on `Y.Parsers` used

                to convert the input value into a normalized type.  Parser

                functions are passed the value as input and are expected to

                return a value.

        If no value parsing is needed, you can use just the desired property

        name string as the field identifier instead of an object (see example

        below).

        @example

            // Process simple csv

            var schema = {

                    resultDelimiter: "\n",

                    fieldDelimiter: ",",

                    resultFields: [ 'fruit', 'color' ]

                },

                data = "Banana,yellow\nOrange,orange\nEggplant,purple";

            var response = Y.DataSchema.Text.apply(schema, data);

            // response.results[0] is { fruit: "Banana", color: "yellow" }

            // Use parsers

            schema.resultFields = [

                {

                    key: 'fruit',

                    parser: function (val) { return val.toUpperCase(); }

                },

                'color' // mix and match objects and strings

            ];

            response = Y.DataSchema.Text.apply(schema, data);

            // response.results[0] is { fruit: "BANANA", color: "yellow" }

        @method apply

        @param {Object} schema Schema to apply.  Supported configuration

            properties are:

          @param {String} schema.resultDelimiter Character or character

              sequence that marks the end of one record and the start of

              another.

          @param {String} [schema.fieldDelimiter] Character or character

              sequence that marks the end of a field and the start of

              another within the same record.

          @param {Array} [schema.resultFields] Field identifiers to

              assign values in the response records. See above for details.

        @param {String} data Text data.

        @return {Object} An Object with properties `results` and `meta`

        @static

        **/

        apply: function(schema, data) {

            var data_in = data,

                data_out = { results: [], meta: {} };

            if (isString(data) && schema && isString(schema.resultDelimiter)) {

                // Parse results data

                data_out = SchemaText._parseResults.call(this, schema, data_in, data_out);

            } else {

                Y.log("Text data could not be schema-parsed: " + Y.dump(data) + " " + Y.dump(data), "error", "dataschema-text");

                data_out.error = new Error("Text schema parse failure");

            }

            return data_out;

        },

        /**

         * Schema-parsed list of results from full data

         *

         * @method _parseResults

         * @param schema {Array} Schema to parse against.

         * @param text_in {String} Text to parse.

         * @param data_out {Object} In-progress parsed data to update.

         * @return {Object} Parsed data object.

         * @static

         * @protected

         */

        _parseResults: function(schema, text_in, data_out) {

            var resultDelim = schema.resultDelimiter,

                fieldDelim  = isString(schema.fieldDelimiter) &&

                                schema.fieldDelimiter,

                fields      = schema.resultFields || [],

                results     = [],

                parse       = Y.DataSchema.Base.parse,

                results_in, fields_in, result, item,

                field, key, value, i, j;

            // Delete final delimiter at end of string if there

            if (text_in.slice(-resultDelim.length) === resultDelim) {

                text_in = text_in.slice(0, -resultDelim.length);

            }

            // Split into results

            results_in = text_in.split(schema.resultDelimiter);

            if (fieldDelim) {

                for (i = results_in.length - 1; i >= 0; --i) {

                    result = {};

                    item = results_in[i];

                    fields_in = item.split(schema.fieldDelimiter);

                    for (j = fields.length - 1; j >= 0; --j) {

                        field = fields[j];

                        key = (!isUndef(field.key)) ? field.key : field;

                        // FIXME: unless the key is an array index, this test

                        // for fields_in[key] is useless.

                        value = (!isUndef(fields_in[key])) ?

                                    fields_in[key] :

                                    fields_in[j];

                        result[key] = parse.call(this, value, field);

                    }

                    results[i] = result;

                }

            } else {

                results = results_in;

            }

            data_out.results = results;

            return data_out;

        }

    };

Y.DataSchema.Text = Y.mix(SchemaText, Y.DataSchema.Base);

}, '3.10.3', {"requires": ["dataschema-base"]});