source: Dev/trunk/src/node_modules/tv4/tv4.js @ 513

/*
Author: Geraint Luff and others
Year: 2013

This code is released into the "public domain" by its author(s).  Anybody may use, alter and distribute the code without restriction.  The author makes no guarantees, and takes no liability of any kind for use of this code.

If you find a bug or make an improvement, it would be courteous to let the author know, but it is not compulsory.
*/
(function (global) {
'use strict';

// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/keys?redirectlocale=en-US&redirectslug=JavaScript%2FReference%2FGlobal_Objects%2FObject%2Fkeys
if (!Object.keys) {
        Object.keys = (function () {
                var hasOwnProperty = Object.prototype.hasOwnProperty,
                        hasDontEnumBug = !({toString: null}).propertyIsEnumerable('toString'),
                        dontEnums = [
                                'toString',
                                'toLocaleString',
                                'valueOf',
                                'hasOwnProperty',
                                'isPrototypeOf',
                                'propertyIsEnumerable',
                                'constructor'
                        ],
                        dontEnumsLength = dontEnums.length;

                return function (obj) {
                        if (typeof obj !== 'object' && typeof obj !== 'function' || obj === null) {
                                throw new TypeError('Object.keys called on non-object');
                        }

                        var result = [];

                        for (var prop in obj) {
                                if (hasOwnProperty.call(obj, prop)) {
                                        result.push(prop);
                                }
                        }

                        if (hasDontEnumBug) {
                                for (var i=0; i < dontEnumsLength; i++) {
                                        if (hasOwnProperty.call(obj, dontEnums[i])) {
                                                result.push(dontEnums[i]);
                                        }
                                }
                        }
                        return result;
                };
        })();
}
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/create
if (!Object.create) {
        Object.create = (function(){
                function F(){}

                return function(o){
                        if (arguments.length !== 1) {
                                throw new Error('Object.create implementation only accepts one parameter.');
                        }
                        F.prototype = o;
                        return new F();
                };
        })();
}
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/isArray?redirectlocale=en-US&redirectslug=JavaScript%2FReference%2FGlobal_Objects%2FArray%2FisArray
if(!Array.isArray) {
        Array.isArray = function (vArg) {
                return Object.prototype.toString.call(vArg) === "[object Array]";
        };
}
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/indexOf?redirectlocale=en-US&redirectslug=JavaScript%2FReference%2FGlobal_Objects%2FArray%2FindexOf
if (!Array.prototype.indexOf) {
        Array.prototype.indexOf = function (searchElement /*, fromIndex */ ) {
                if (this === null) {
                        throw new TypeError();
                }
                var t = Object(this);
                var len = t.length >>> 0;

                if (len === 0) {
                        return -1;
                }
                var n = 0;
                if (arguments.length > 1) {
                        n = Number(arguments[1]);
                        if (n !== n) { // shortcut for verifying if it's NaN
                                n = 0;
                        } else if (n !== 0 && n !== Infinity && n !== -Infinity) {
                                n = (n > 0 || -1) * Math.floor(Math.abs(n));
                        }
                }
                if (n >= len) {
                        return -1;
                }
                var k = n >= 0 ? n : Math.max(len - Math.abs(n), 0);
                for (; k < len; k++) {
                        if (k in t && t[k] === searchElement) {
                                return k;
                        }
                }
                return -1;
        };
}

// Grungey Object.isFrozen hack
if (!Object.isFrozen) {
        Object.isFrozen = function (obj) {
                var key = "tv4_test_frozen_key";
                while (obj.hasOwnProperty(key)) {
                        key += Math.random();
                }
                try {
                        obj[key] = true;
                        delete obj[key];
                        return false;
                } catch (e) {
                        return true;
                }
        };
}
var ValidatorContext = function ValidatorContext(parent, collectMultiple, errorMessages, checkRecursive, trackUnknownProperties) {
        this.missing = [];
        this.missingMap = {};
        this.formatValidators = parent ? Object.create(parent.formatValidators) : {};
        this.schemas = parent ? Object.create(parent.schemas) : {};
        this.collectMultiple = collectMultiple;
        this.errors = [];
        this.handleError = collectMultiple ? this.collectError : this.returnError;
        if (checkRecursive) {
                this.checkRecursive = true;
                this.scanned = [];
                this.scannedFrozen = [];
                this.scannedFrozenSchemas = [];
                this.scannedFrozenValidationErrors = [];
                this.validatedSchemasKey = 'tv4_validation_id';
                this.validationErrorsKey = 'tv4_validation_errors_id';
        }
        if (trackUnknownProperties) {
                this.trackUnknownProperties = true;
                this.knownPropertyPaths = {};
                this.unknownPropertyPaths = {};
        }
        this.errorMessages = errorMessages;
};
ValidatorContext.prototype.createError = function (code, messageParams, dataPath, schemaPath, subErrors) {
        var messageTemplate = this.errorMessages[code] || ErrorMessagesDefault[code];
        if (typeof messageTemplate !== 'string') {
                return new ValidationError(code, "Unknown error code " + code + ": " + JSON.stringify(messageParams), dataPath, schemaPath, subErrors);
        }
        // Adapted from Crockford's supplant()
        var message = messageTemplate.replace(/\{([^{}]*)\}/g, function (whole, varName) {
                var subValue = messageParams[varName];
                return typeof subValue === 'string' || typeof subValue === 'number' ? subValue : whole;
        });
        return new ValidationError(code, message, dataPath, schemaPath, subErrors);
};
ValidatorContext.prototype.returnError = function (error) {
        return error;
};
ValidatorContext.prototype.collectError = function (error) {
        if (error) {
                this.errors.push(error);
        }
        return null;
};
ValidatorContext.prototype.prefixErrors = function (startIndex, dataPath, schemaPath) {
        for (var i = startIndex; i < this.errors.length; i++) {
                this.errors[i] = this.errors[i].prefixWith(dataPath, schemaPath);
        }
        return this;
};
ValidatorContext.prototype.banUnknownProperties = function () {
        for (var unknownPath in this.unknownPropertyPaths) {
                var error = this.createError(ErrorCodes.UNKNOWN_PROPERTY, {path: unknownPath}, unknownPath, "");
                var result = this.handleError(error);
                if (result) {
                        return result;
                }
        }
        return null;
};

ValidatorContext.prototype.addFormat = function (format, validator) {
        if (typeof format === 'object') {
                for (var key in format) {
                        this.addFormat(key, format[key]);
                }
                return this;
        }
        this.formatValidators[format] = validator;
};
ValidatorContext.prototype.resolveRefs = function (schema, urlHistory) {
        if (schema['$ref'] !== undefined) {
                urlHistory = urlHistory || {};
                if (urlHistory[schema['$ref']]) {
                        return this.createError(ErrorCodes.CIRCULAR_REFERENCE, {urls: Object.keys(urlHistory).join(', ')}, '', '');
                }
                urlHistory[schema['$ref']] = true;
                schema = this.getSchema(schema['$ref'], urlHistory);
        }
        return schema;
};
ValidatorContext.prototype.getSchema = function (url, urlHistory) {
        var schema;
        if (this.schemas[url] !== undefined) {
                schema = this.schemas[url];
                return this.resolveRefs(schema, urlHistory);
        }
        var baseUrl = url;
        var fragment = "";
        if (url.indexOf('#') !== -1) {
                fragment = url.substring(url.indexOf("#") + 1);
                baseUrl = url.substring(0, url.indexOf("#"));
        }
        if (typeof this.schemas[baseUrl] === 'object') {
                schema = this.schemas[baseUrl];
                var pointerPath = decodeURIComponent(fragment);
                if (pointerPath === "") {
                        return this.resolveRefs(schema, urlHistory);
                } else if (pointerPath.charAt(0) !== "/") {
                        return undefined;
                }
                var parts = pointerPath.split("/").slice(1);
                for (var i = 0; i < parts.length; i++) {
                        var component = parts[i].replace(/~1/g, "/").replace(/~0/g, "~");
                        if (schema[component] === undefined) {
                                schema = undefined;
                                break;
                        }
                        schema = schema[component];
                }
                if (schema !== undefined) {
                        return this.resolveRefs(schema, urlHistory);
                }
        }
        if (this.missing[baseUrl] === undefined) {
                this.missing.push(baseUrl);
                this.missing[baseUrl] = baseUrl;
                this.missingMap[baseUrl] = baseUrl;
        }
};
ValidatorContext.prototype.searchSchemas = function (schema, url) {
        if (schema && typeof schema === "object") {
                if (typeof schema.id === "string") {
                        if (isTrustedUrl(url, schema.id)) {
                                if (this.schemas[schema.id] === undefined) {
                                        this.schemas[schema.id] = schema;
                                }
                        }
                }
                for (var key in schema) {
                        if (key !== "enum") {
                                if (typeof schema[key] === "object") {
                                        this.searchSchemas(schema[key], url);
                                } else if (key === "$ref") {
                                        var uri = getDocumentUri(schema[key]);
                                        if (uri && this.schemas[uri] === undefined && this.missingMap[uri] === undefined) {
                                                this.missingMap[uri] = uri;
                                        }
                                }
                        }
                }
        }
};
ValidatorContext.prototype.addSchema = function (url, schema) {
        //overload
        if (typeof url !== 'string' || typeof schema === 'undefined') {
                if (typeof url === 'object' && typeof url.id === 'string') {
                        schema = url;
                        url = schema.id;
                }
                else {
                        return;
                }
        }
        if (url = getDocumentUri(url) + "#") {
                // Remove empty fragment
                url = getDocumentUri(url);
        }
        this.schemas[url] = schema;
        delete this.missingMap[url];
        normSchema(schema, url);
        this.searchSchemas(schema, url);
};

ValidatorContext.prototype.getSchemaMap = function () {
        var map = {};
        for (var key in this.schemas) {
                map[key] = this.schemas[key];
        }
        return map;
};

ValidatorContext.prototype.getSchemaUris = function (filterRegExp) {
        var list = [];
        for (var key in this.schemas) {
                if (!filterRegExp || filterRegExp.test(key)) {
                        list.push(key);
                }
        }
        return list;
};

ValidatorContext.prototype.getMissingUris = function (filterRegExp) {
        var list = [];
        for (var key in this.missingMap) {
                if (!filterRegExp || filterRegExp.test(key)) {
                        list.push(key);
                }
        }
        return list;
};

ValidatorContext.prototype.dropSchemas = function () {
        this.schemas = {};
        this.reset();
};
ValidatorContext.prototype.reset = function () {
        this.missing = [];
        this.missingMap = {};
        this.errors = [];
};

ValidatorContext.prototype.validateAll = function (data, schema, dataPathParts, schemaPathParts, dataPointerPath) {
        var topLevel;
        schema = this.resolveRefs(schema);
        if (!schema) {
                return null;
        } else if (schema instanceof ValidationError) {
                this.errors.push(schema);
                return schema;
        }

        var startErrorCount = this.errors.length;
        var frozenIndex, scannedFrozenSchemaIndex = null, scannedSchemasIndex = null;
        if (this.checkRecursive && data && typeof data === 'object') {
                topLevel = !this.scanned.length;
                if (data[this.validatedSchemasKey]) {
                        var schemaIndex = data[this.validatedSchemasKey].indexOf(schema);
                        if (schemaIndex !== -1) {
                                this.errors = this.errors.concat(data[this.validationErrorsKey][schemaIndex]);
                                return null;
                        }
                }
                if (Object.isFrozen(data)) {
                        frozenIndex = this.scannedFrozen.indexOf(data);
                        if (frozenIndex !== -1) {
                                var frozenSchemaIndex = this.scannedFrozenSchemas[frozenIndex].indexOf(schema);
                                if (frozenSchemaIndex !== -1) {
                                        this.errors = this.errors.concat(this.scannedFrozenValidationErrors[frozenIndex][frozenSchemaIndex]);
                                        return null;
                                }
                        }
                }
                this.scanned.push(data);
                if (Object.isFrozen(data)) {
                        if (frozenIndex === -1) {
                                frozenIndex = this.scannedFrozen.length;
                                this.scannedFrozen.push(data);
                                this.scannedFrozenSchemas.push([]);
                        }
                        scannedFrozenSchemaIndex = this.scannedFrozenSchemas[frozenIndex].length;
                        this.scannedFrozenSchemas[frozenIndex][scannedFrozenSchemaIndex] = schema;
                        this.scannedFrozenValidationErrors[frozenIndex][scannedFrozenSchemaIndex] = [];
                } else {
                        if (!data[this.validatedSchemasKey]) {
                                try {
                                        Object.defineProperty(data, this.validatedSchemasKey, {
                                                value: [],
                                                configurable: true
                                        });
                                        Object.defineProperty(data, this.validationErrorsKey, {
                                                value: [],
                                                configurable: true
                                        });
                                } catch (e) {
                                        //IE 7/8 workaround
                                        data[this.validatedSchemasKey] = [];
                                        data[this.validationErrorsKey] = [];
                                }
                        }
                        scannedSchemasIndex = data[this.validatedSchemasKey].length;
                        data[this.validatedSchemasKey][scannedSchemasIndex] = schema;
                        data[this.validationErrorsKey][scannedSchemasIndex] = [];
                }
        }

        var errorCount = this.errors.length;
        var error = this.validateBasic(data, schema, dataPointerPath)
                || this.validateNumeric(data, schema, dataPointerPath)
                || this.validateString(data, schema, dataPointerPath)
                || this.validateArray(data, schema, dataPointerPath)
                || this.validateObject(data, schema, dataPointerPath)
                || this.validateCombinations(data, schema, dataPointerPath)
                || this.validateFormat(data, schema, dataPointerPath)
                || null;

        if (topLevel) {
                while (this.scanned.length) {
                        var item = this.scanned.pop();
                        delete item[this.validatedSchemasKey];
                }
                this.scannedFrozen = [];
                this.scannedFrozenSchemas = [];
        }

        if (error || errorCount !== this.errors.length) {
                while ((dataPathParts && dataPathParts.length) || (schemaPathParts && schemaPathParts.length)) {
                        var dataPart = (dataPathParts && dataPathParts.length) ? "" + dataPathParts.pop() : null;
                        var schemaPart = (schemaPathParts && schemaPathParts.length) ? "" + schemaPathParts.pop() : null;
                        if (error) {
                                error = error.prefixWith(dataPart, schemaPart);
                        }
                        this.prefixErrors(errorCount, dataPart, schemaPart);
                }
        }
        
        if (scannedFrozenSchemaIndex !== null) {
                this.scannedFrozenValidationErrors[frozenIndex][scannedFrozenSchemaIndex] = this.errors.slice(startErrorCount);
        } else if (scannedSchemasIndex !== null) {
                data[this.validationErrorsKey][scannedSchemasIndex] = this.errors.slice(startErrorCount);
        }

        return this.handleError(error);
};
ValidatorContext.prototype.validateFormat = function (data, schema) {
        if (typeof schema.format !== 'string' || !this.formatValidators[schema.format]) {
                return null;
        }
        var errorMessage = this.formatValidators[schema.format].call(null, data, schema);
        if (typeof errorMessage === 'string' || typeof errorMessage === 'number') {
                return this.createError(ErrorCodes.FORMAT_CUSTOM, {message: errorMessage}).prefixWith(null, "format");
        } else if (errorMessage && typeof errorMessage === 'object') {
                return this.createError(ErrorCodes.FORMAT_CUSTOM, {message: errorMessage.message || "?"}, errorMessage.dataPath || null, errorMessage.schemaPath || "/format");
        }
        return null;
};

function recursiveCompare(A, B) {
        if (A === B) {
                return true;
        }
        if (typeof A === "object" && typeof B === "object") {
                if (Array.isArray(A) !== Array.isArray(B)) {
                        return false;
                } else if (Array.isArray(A)) {
                        if (A.length !== B.length) {
                                return false;
                        }
                        for (var i = 0; i < A.length; i++) {
                                if (!recursiveCompare(A[i], B[i])) {
                                        return false;
                                }
                        }
                } else {
                        var key;
                        for (key in A) {
                                if (B[key] === undefined && A[key] !== undefined) {
                                        return false;
                                }
                        }
                        for (key in B) {
                                if (A[key] === undefined && B[key] !== undefined) {
                                        return false;
                                }
                        }
                        for (key in A) {
                                if (!recursiveCompare(A[key], B[key])) {
                                        return false;
                                }
                        }
                }
                return true;
        }
        return false;
}

ValidatorContext.prototype.validateBasic = function validateBasic(data, schema, dataPointerPath) {
        var error;
        if (error = this.validateType(data, schema, dataPointerPath)) {
                return error.prefixWith(null, "type");
        }
        if (error = this.validateEnum(data, schema, dataPointerPath)) {
                return error.prefixWith(null, "type");
        }
        return null;
};

ValidatorContext.prototype.validateType = function validateType(data, schema) {
        if (schema.type === undefined) {
                return null;
        }
        var dataType = typeof data;
        if (data === null) {
                dataType = "null";
        } else if (Array.isArray(data)) {
                dataType = "array";
        }
        var allowedTypes = schema.type;
        if (typeof allowedTypes !== "object") {
                allowedTypes = [allowedTypes];
        }

        for (var i = 0; i < allowedTypes.length; i++) {
                var type = allowedTypes[i];
                if (type === dataType || (type === "integer" && dataType === "number" && (data % 1 === 0))) {
                        return null;
                }
        }
        return this.createError(ErrorCodes.INVALID_TYPE, {type: dataType, expected: allowedTypes.join("/")});
};

ValidatorContext.prototype.validateEnum = function validateEnum(data, schema) {
        if (schema["enum"] === undefined) {
                return null;
        }
        for (var i = 0; i < schema["enum"].length; i++) {
                var enumVal = schema["enum"][i];
                if (recursiveCompare(data, enumVal)) {
                        return null;
                }
        }
        return this.createError(ErrorCodes.ENUM_MISMATCH, {value: (typeof JSON !== 'undefined') ? JSON.stringify(data) : data});
};

ValidatorContext.prototype.validateNumeric = function validateNumeric(data, schema, dataPointerPath) {
        return this.validateMultipleOf(data, schema, dataPointerPath)
                || this.validateMinMax(data, schema, dataPointerPath)
                || null;
};

ValidatorContext.prototype.validateMultipleOf = function validateMultipleOf(data, schema) {
        var multipleOf = schema.multipleOf || schema.divisibleBy;
        if (multipleOf === undefined) {
                return null;
        }
        if (typeof data === "number") {
                if (data % multipleOf !== 0) {
                        return this.createError(ErrorCodes.NUMBER_MULTIPLE_OF, {value: data, multipleOf: multipleOf});
                }
        }
        return null;
};

ValidatorContext.prototype.validateMinMax = function validateMinMax(data, schema) {
        if (typeof data !== "number") {
                return null;
        }
        if (schema.minimum !== undefined) {
                if (data < schema.minimum) {
                        return this.createError(ErrorCodes.NUMBER_MINIMUM, {value: data, minimum: schema.minimum}).prefixWith(null, "minimum");
                }
                if (schema.exclusiveMinimum && data === schema.minimum) {
                        return this.createError(ErrorCodes.NUMBER_MINIMUM_EXCLUSIVE, {value: data, minimum: schema.minimum}).prefixWith(null, "exclusiveMinimum");
                }
        }
        if (schema.maximum !== undefined) {
                if (data > schema.maximum) {
                        return this.createError(ErrorCodes.NUMBER_MAXIMUM, {value: data, maximum: schema.maximum}).prefixWith(null, "maximum");
                }
                if (schema.exclusiveMaximum && data === schema.maximum) {
                        return this.createError(ErrorCodes.NUMBER_MAXIMUM_EXCLUSIVE, {value: data, maximum: schema.maximum}).prefixWith(null, "exclusiveMaximum");
                }
        }
        return null;
};

ValidatorContext.prototype.validateString = function validateString(data, schema, dataPointerPath) {
        return this.validateStringLength(data, schema, dataPointerPath)
                || this.validateStringPattern(data, schema, dataPointerPath)
                || null;
};

ValidatorContext.prototype.validateStringLength = function validateStringLength(data, schema) {
        if (typeof data !== "string") {
                return null;
        }
        if (schema.minLength !== undefined) {
                if (data.length < schema.minLength) {
                        return this.createError(ErrorCodes.STRING_LENGTH_SHORT, {length: data.length, minimum: schema.minLength}).prefixWith(null, "minLength");
                }
        }
        if (schema.maxLength !== undefined) {
                if (data.length > schema.maxLength) {
                        return this.createError(ErrorCodes.STRING_LENGTH_LONG, {length: data.length, maximum: schema.maxLength}).prefixWith(null, "maxLength");
                }
        }
        return null;
};

ValidatorContext.prototype.validateStringPattern = function validateStringPattern(data, schema) {
        if (typeof data !== "string" || schema.pattern === undefined) {
                return null;
        }
        var regexp = new RegExp(schema.pattern);
        if (!regexp.test(data)) {
                return this.createError(ErrorCodes.STRING_PATTERN, {pattern: schema.pattern}).prefixWith(null, "pattern");
        }
        return null;
};
ValidatorContext.prototype.validateArray = function validateArray(data, schema, dataPointerPath) {
        if (!Array.isArray(data)) {
                return null;
        }
        return this.validateArrayLength(data, schema, dataPointerPath)
                || this.validateArrayUniqueItems(data, schema, dataPointerPath)
                || this.validateArrayItems(data, schema, dataPointerPath)
                || null;
};

ValidatorContext.prototype.validateArrayLength = function validateArrayLength(data, schema) {
        var error;
        if (schema.minItems !== undefined) {
                if (data.length < schema.minItems) {
                        error = (this.createError(ErrorCodes.ARRAY_LENGTH_SHORT, {length: data.length, minimum: schema.minItems})).prefixWith(null, "minItems");
                        if (this.handleError(error)) {
                                return error;
                        }
                }
        }
        if (schema.maxItems !== undefined) {
                if (data.length > schema.maxItems) {
                        error = (this.createError(ErrorCodes.ARRAY_LENGTH_LONG, {length: data.length, maximum: schema.maxItems})).prefixWith(null, "maxItems");
                        if (this.handleError(error)) {
                                return error;
                        }
                }
        }
        return null;
};

ValidatorContext.prototype.validateArrayUniqueItems = function validateArrayUniqueItems(data, schema) {
        if (schema.uniqueItems) {
                for (var i = 0; i < data.length; i++) {
                        for (var j = i + 1; j < data.length; j++) {
                                if (recursiveCompare(data[i], data[j])) {
                                        var error = (this.createError(ErrorCodes.ARRAY_UNIQUE, {match1: i, match2: j})).prefixWith(null, "uniqueItems");
                                        if (this.handleError(error)) {
                                                return error;
                                        }
                                }
                        }
                }
        }
        return null;
};

ValidatorContext.prototype.validateArrayItems = function validateArrayItems(data, schema, dataPointerPath) {
        if (schema.items === undefined) {
                return null;
        }
        var error, i;
        if (Array.isArray(schema.items)) {
                for (i = 0; i < data.length; i++) {
                        if (i < schema.items.length) {
                                if (error = this.validateAll(data[i], schema.items[i], [i], ["items", i], dataPointerPath + "/" + i)) {
                                        return error;
                                }
                        } else if (schema.additionalItems !== undefined) {
                                if (typeof schema.additionalItems === "boolean") {
                                        if (!schema.additionalItems) {
                                                error = (this.createError(ErrorCodes.ARRAY_ADDITIONAL_ITEMS, {})).prefixWith("" + i, "additionalItems");
                                                if (this.handleError(error)) {
                                                        return error;
                                                }
                                        }
                                } else if (error = this.validateAll(data[i], schema.additionalItems, [i], ["additionalItems"], dataPointerPath + "/" + i)) {
                                        return error;
                                }
                        }
                }
        } else {
                for (i = 0; i < data.length; i++) {
                        if (error = this.validateAll(data[i], schema.items, [i], ["items"], dataPointerPath + "/" + i)) {
                                return error;
                        }
                }
        }
        return null;
};

ValidatorContext.prototype.validateObject = function validateObject(data, schema, dataPointerPath) {
        if (typeof data !== "object" || data === null || Array.isArray(data)) {
                return null;
        }
        return this.validateObjectMinMaxProperties(data, schema, dataPointerPath)
                || this.validateObjectRequiredProperties(data, schema, dataPointerPath)
                || this.validateObjectProperties(data, schema, dataPointerPath)
                || this.validateObjectDependencies(data, schema, dataPointerPath)
                || null;
};

ValidatorContext.prototype.validateObjectMinMaxProperties = function validateObjectMinMaxProperties(data, schema) {
        var keys = Object.keys(data);
        var error;
        if (schema.minProperties !== undefined) {
                if (keys.length < schema.minProperties) {
                        error = this.createError(ErrorCodes.OBJECT_PROPERTIES_MINIMUM, {propertyCount: keys.length, minimum: schema.minProperties}).prefixWith(null, "minProperties");
                        if (this.handleError(error)) {
                                return error;
                        }
                }
        }
        if (schema.maxProperties !== undefined) {
                if (keys.length > schema.maxProperties) {
                        error = this.createError(ErrorCodes.OBJECT_PROPERTIES_MAXIMUM, {propertyCount: keys.length, maximum: schema.maxProperties}).prefixWith(null, "maxProperties");
                        if (this.handleError(error)) {
                                return error;
                        }
                }
        }
        return null;
};

ValidatorContext.prototype.validateObjectRequiredProperties = function validateObjectRequiredProperties(data, schema) {
        if (schema.required !== undefined) {
                for (var i = 0; i < schema.required.length; i++) {
                        var key = schema.required[i];
                        if (data[key] === undefined) {
                                var error = this.createError(ErrorCodes.OBJECT_REQUIRED, {key: key}).prefixWith(null, "" + i).prefixWith(null, "required");
                                if (this.handleError(error)) {
                                        return error;
                                }
                        }
                }
        }
        return null;
};

ValidatorContext.prototype.validateObjectProperties = function validateObjectProperties(data, schema, dataPointerPath) {
        var error;
        for (var key in data) {
                var keyPointerPath = dataPointerPath + "/" + key.replace(/~/g, '~0').replace(/\//g, '~1');
                var foundMatch = false;
                if (schema.properties !== undefined && schema.properties[key] !== undefined) {
                        foundMatch = true;
                        if (error = this.validateAll(data[key], schema.properties[key], [key], ["properties", key], keyPointerPath)) {
                                return error;
                        }
                }
                if (schema.patternProperties !== undefined) {
                        for (var patternKey in schema.patternProperties) {
                                var regexp = new RegExp(patternKey);
                                if (regexp.test(key)) {
                                        foundMatch = true;
                                        if (error = this.validateAll(data[key], schema.patternProperties[patternKey], [key], ["patternProperties", patternKey], keyPointerPath)) {
                                                return error;
                                        }
                                }
                        }
                }
                if (!foundMatch) {
                        if (schema.additionalProperties !== undefined) {
                                if (this.trackUnknownProperties) {
                                        this.knownPropertyPaths[keyPointerPath] = true;
                                        delete this.unknownPropertyPaths[keyPointerPath];
                                }
                                if (typeof schema.additionalProperties === "boolean") {
                                        if (!schema.additionalProperties) {
                                                error = this.createError(ErrorCodes.OBJECT_ADDITIONAL_PROPERTIES, {}).prefixWith(key, "additionalProperties");
                                                if (this.handleError(error)) {
                                                        return error;
                                                }
                                        }
                                } else {
                                        if (error = this.validateAll(data[key], schema.additionalProperties, [key], ["additionalProperties"], keyPointerPath)) {
                                                return error;
                                        }
                                }
                        } else if (this.trackUnknownProperties && !this.knownPropertyPaths[keyPointerPath]) {
                                this.unknownPropertyPaths[keyPointerPath] = true;
                        }
                } else if (this.trackUnknownProperties) {
                        this.knownPropertyPaths[keyPointerPath] = true;
                        delete this.unknownPropertyPaths[keyPointerPath];
                }
        }
        return null;
};

ValidatorContext.prototype.validateObjectDependencies = function validateObjectDependencies(data, schema, dataPointerPath) {
        var error;
        if (schema.dependencies !== undefined) {
                for (var depKey in schema.dependencies) {
                        if (data[depKey] !== undefined) {
                                var dep = schema.dependencies[depKey];
                                if (typeof dep === "string") {
                                        if (data[dep] === undefined) {
                                                error = this.createError(ErrorCodes.OBJECT_DEPENDENCY_KEY, {key: depKey, missing: dep}).prefixWith(null, depKey).prefixWith(null, "dependencies");
                                                if (this.handleError(error)) {
                                                        return error;
                                                }
                                        }
                                } else if (Array.isArray(dep)) {
                                        for (var i = 0; i < dep.length; i++) {
                                                var requiredKey = dep[i];
                                                if (data[requiredKey] === undefined) {
                                                        error = this.createError(ErrorCodes.OBJECT_DEPENDENCY_KEY, {key: depKey, missing: requiredKey}).prefixWith(null, "" + i).prefixWith(null, depKey).prefixWith(null, "dependencies");
                                                        if (this.handleError(error)) {
                                                                return error;
                                                        }
                                                }
                                        }
                                } else {
                                        if (error = this.validateAll(data, dep, [], ["dependencies", depKey], dataPointerPath)) {
                                                return error;
                                        }
                                }
                        }
                }
        }
        return null;
};

ValidatorContext.prototype.validateCombinations = function validateCombinations(data, schema, dataPointerPath) {
        return this.validateAllOf(data, schema, dataPointerPath)
                || this.validateAnyOf(data, schema, dataPointerPath)
                || this.validateOneOf(data, schema, dataPointerPath)
                || this.validateNot(data, schema, dataPointerPath)
                || null;
};

ValidatorContext.prototype.validateAllOf = function validateAllOf(data, schema, dataPointerPath) {
        if (schema.allOf === undefined) {
                return null;
        }
        var error;
        for (var i = 0; i < schema.allOf.length; i++) {
                var subSchema = schema.allOf[i];
                if (error = this.validateAll(data, subSchema, [], ["allOf", i], dataPointerPath)) {
                        return error;
                }
        }
        return null;
};

ValidatorContext.prototype.validateAnyOf = function validateAnyOf(data, schema, dataPointerPath) {
        if (schema.anyOf === undefined) {
                return null;
        }
        var errors = [];
        var startErrorCount = this.errors.length;
        var oldUnknownPropertyPaths, oldKnownPropertyPaths;
        if (this.trackUnknownProperties) {
                oldUnknownPropertyPaths = this.unknownPropertyPaths;
                oldKnownPropertyPaths = this.knownPropertyPaths;
        }
        var errorAtEnd = true;
        for (var i = 0; i < schema.anyOf.length; i++) {
                if (this.trackUnknownProperties) {
                        this.unknownPropertyPaths = {};
                        this.knownPropertyPaths = {};
                }
                var subSchema = schema.anyOf[i];

                var errorCount = this.errors.length;
                var error = this.validateAll(data, subSchema, [], ["anyOf", i], dataPointerPath);

                if (error === null && errorCount === this.errors.length) {
                        this.errors = this.errors.slice(0, startErrorCount);

                        if (this.trackUnknownProperties) {
                                for (var knownKey in this.knownPropertyPaths) {
                                        oldKnownPropertyPaths[knownKey] = true;
                                        delete oldUnknownPropertyPaths[knownKey];
                                }
                                for (var unknownKey in this.unknownPropertyPaths) {
                                        if (!oldKnownPropertyPaths[unknownKey]) {
                                                oldUnknownPropertyPaths[unknownKey] = true;
                                        }
                                }
                                // We need to continue looping so we catch all the property definitions, but we don't want to return an error
                                errorAtEnd = false;
                                continue;
                        }

                        return null;
                }
                if (error) {
                        errors.push(error.prefixWith(null, "" + i).prefixWith(null, "anyOf"));
                }
        }
        if (this.trackUnknownProperties) {
                this.unknownPropertyPaths = oldUnknownPropertyPaths;
                this.knownPropertyPaths = oldKnownPropertyPaths;
        }
        if (errorAtEnd) {
                errors = errors.concat(this.errors.slice(startErrorCount));
                this.errors = this.errors.slice(0, startErrorCount);
                return this.createError(ErrorCodes.ANY_OF_MISSING, {}, "", "/anyOf", errors);
        }
};

ValidatorContext.prototype.validateOneOf = function validateOneOf(data, schema, dataPointerPath) {
        if (schema.oneOf === undefined) {
                return null;
        }
        var validIndex = null;
        var errors = [];
        var startErrorCount = this.errors.length;
        var oldUnknownPropertyPaths, oldKnownPropertyPaths;
        if (this.trackUnknownProperties) {
                oldUnknownPropertyPaths = this.unknownPropertyPaths;
                oldKnownPropertyPaths = this.knownPropertyPaths;
        }
        for (var i = 0; i < schema.oneOf.length; i++) {
                if (this.trackUnknownProperties) {
                        this.unknownPropertyPaths = {};
                        this.knownPropertyPaths = {};
                }
                var subSchema = schema.oneOf[i];

                var errorCount = this.errors.length;
                var error = this.validateAll(data, subSchema, [], ["oneOf", i], dataPointerPath);

                if (error === null && errorCount === this.errors.length) {
                        if (validIndex === null) {
                                validIndex = i;
                        } else {
                                this.errors = this.errors.slice(0, startErrorCount);
                                return this.createError(ErrorCodes.ONE_OF_MULTIPLE, {index1: validIndex, index2: i}, "", "/oneOf");
                        }
                        if (this.trackUnknownProperties) {
                                for (var knownKey in this.knownPropertyPaths) {
                                        oldKnownPropertyPaths[knownKey] = true;
                                        delete oldUnknownPropertyPaths[knownKey];
                                }
                                for (var unknownKey in this.unknownPropertyPaths) {
                                        if (!oldKnownPropertyPaths[unknownKey]) {
                                                oldUnknownPropertyPaths[unknownKey] = true;
                                        }
                                }
                        }
                } else if (error) {
                        errors.push(error.prefixWith(null, "" + i).prefixWith(null, "oneOf"));
                }
        }
        if (this.trackUnknownProperties) {
                this.unknownPropertyPaths = oldUnknownPropertyPaths;
                this.knownPropertyPaths = oldKnownPropertyPaths;
        }
        if (validIndex === null) {
                errors = errors.concat(this.errors.slice(startErrorCount));
                this.errors = this.errors.slice(0, startErrorCount);
                return this.createError(ErrorCodes.ONE_OF_MISSING, {}, "", "/oneOf", errors);
        } else {
                this.errors = this.errors.slice(0, startErrorCount);
        }
        return null;
};

ValidatorContext.prototype.validateNot = function validateNot(data, schema, dataPointerPath) {
        if (schema.not === undefined) {
                return null;
        }
        var oldErrorCount = this.errors.length;
        var oldUnknownPropertyPaths, oldKnownPropertyPaths;
        if (this.trackUnknownProperties) {
                oldUnknownPropertyPaths = this.unknownPropertyPaths;
                oldKnownPropertyPaths = this.knownPropertyPaths;
                this.unknownPropertyPaths = {};
                this.knownPropertyPaths = {};
        }
        var error = this.validateAll(data, schema.not, null, null, dataPointerPath);
        var notErrors = this.errors.slice(oldErrorCount);
        this.errors = this.errors.slice(0, oldErrorCount);
        if (this.trackUnknownProperties) {
                this.unknownPropertyPaths = oldUnknownPropertyPaths;
                this.knownPropertyPaths = oldKnownPropertyPaths;
        }
        if (error === null && notErrors.length === 0) {
                return this.createError(ErrorCodes.NOT_PASSED, {}, "", "/not");
        }
        return null;
};

// parseURI() and resolveUrl() are from https://gist.github.com/1088850
//   -  released as public domain by author ("Yaffle") - see comments on gist

function parseURI(url) {
        var m = String(url).replace(/^\s+|\s+$/g, '').match(/^([^:\/?#]+:)?(\/\/(?:[^:@]*(?::[^:@]*)?@)?(([^:\/?#]*)(?::(\d*))?))?([^?#]*)(\?[^#]*)?(#[\s\S]*)?/);
        // authority = '//' + user + ':' + pass '@' + hostname + ':' port
        return (m ? {
                href     : m[0] || '',
                protocol : m[1] || '',
                authority: m[2] || '',
                host     : m[3] || '',
                hostname : m[4] || '',
                port     : m[5] || '',
                pathname : m[6] || '',
                search   : m[7] || '',
                hash     : m[8] || ''
        } : null);
}

function resolveUrl(base, href) {// RFC 3986

        function removeDotSegments(input) {
                var output = [];
                input.replace(/^(\.\.?(\/|$))+/, '')
                        .replace(/\/(\.(\/|$))+/g, '/')
                        .replace(/\/\.\.$/, '/../')
                        .replace(/\/?[^\/]*/g, function (p) {
                                if (p === '/..') {
                                        output.pop();
                                } else {
                                        output.push(p);
                                }
                });
                return output.join('').replace(/^\//, input.charAt(0) === '/' ? '/' : '');
        }

        href = parseURI(href || '');
        base = parseURI(base || '');

        return !href || !base ? null : (href.protocol || base.protocol) +
                (href.protocol || href.authority ? href.authority : base.authority) +
                removeDotSegments(href.protocol || href.authority || href.pathname.charAt(0) === '/' ? href.pathname : (href.pathname ? ((base.authority && !base.pathname ? '/' : '') + base.pathname.slice(0, base.pathname.lastIndexOf('/') + 1) + href.pathname) : base.pathname)) +
                (href.protocol || href.authority || href.pathname ? href.search : (href.search || base.search)) +
                href.hash;
}

function getDocumentUri(uri) {
        return uri.split('#')[0];
}
function normSchema(schema, baseUri) {
        if (schema && typeof schema === "object") {
                if (baseUri === undefined) {
                        baseUri = schema.id;
                } else if (typeof schema.id === "string") {
                        baseUri = resolveUrl(baseUri, schema.id);
                        schema.id = baseUri;
                }
                if (Array.isArray(schema)) {
                        for (var i = 0; i < schema.length; i++) {
                                normSchema(schema[i], baseUri);
                        }
                } else if (typeof schema['$ref'] === "string") {
                        schema['$ref'] = resolveUrl(baseUri, schema['$ref']);
                } else {
                        for (var key in schema) {
                                if (key !== "enum") {
                                        normSchema(schema[key], baseUri);
                                }
                        }
                }
        }
}

var ErrorCodes = {
        INVALID_TYPE: 0,
        ENUM_MISMATCH: 1,
        ANY_OF_MISSING: 10,
        ONE_OF_MISSING: 11,
        ONE_OF_MULTIPLE: 12,
        NOT_PASSED: 13,
        // Numeric errors
        NUMBER_MULTIPLE_OF: 100,
        NUMBER_MINIMUM: 101,
        NUMBER_MINIMUM_EXCLUSIVE: 102,
        NUMBER_MAXIMUM: 103,
        NUMBER_MAXIMUM_EXCLUSIVE: 104,
        // String errors
        STRING_LENGTH_SHORT: 200,
        STRING_LENGTH_LONG: 201,
        STRING_PATTERN: 202,
        // Object errors
        OBJECT_PROPERTIES_MINIMUM: 300,
        OBJECT_PROPERTIES_MAXIMUM: 301,
        OBJECT_REQUIRED: 302,
        OBJECT_ADDITIONAL_PROPERTIES: 303,
        OBJECT_DEPENDENCY_KEY: 304,
        // Array errors
        ARRAY_LENGTH_SHORT: 400,
        ARRAY_LENGTH_LONG: 401,
        ARRAY_UNIQUE: 402,
        ARRAY_ADDITIONAL_ITEMS: 403,
        // Format errors
        FORMAT_CUSTOM: 500,
        // Schema structure
        CIRCULAR_REFERENCE: 600,
        // Non-standard validation options
        UNKNOWN_PROPERTY: 1000
};
var ErrorMessagesDefault = {
        INVALID_TYPE: "invalid type: {type} (expected {expected})",
        ENUM_MISMATCH: "No enum match for: {value}",
        ANY_OF_MISSING: "Data does not match any schemas from \"anyOf\"",
        ONE_OF_MISSING: "Data does not match any schemas from \"oneOf\"",
        ONE_OF_MULTIPLE: "Data is valid against more than one schema from \"oneOf\": indices {index1} and {index2}",
        NOT_PASSED: "Data matches schema from \"not\"",
        // Numeric errors
        NUMBER_MULTIPLE_OF: "Value {value} is not a multiple of {multipleOf}",
        NUMBER_MINIMUM: "Value {value} is less than minimum {minimum}",
        NUMBER_MINIMUM_EXCLUSIVE: "Value {value} is equal to exclusive minimum {minimum}",
        NUMBER_MAXIMUM: "Value {value} is greater than maximum {maximum}",
        NUMBER_MAXIMUM_EXCLUSIVE: "Value {value} is equal to exclusive maximum {maximum}",
        // String errors
        STRING_LENGTH_SHORT: "String is too short ({length} chars), minimum {minimum}",
        STRING_LENGTH_LONG: "String is too long ({length} chars), maximum {maximum}",
        STRING_PATTERN: "String does not match pattern: {pattern}",
        // Object errors
        OBJECT_PROPERTIES_MINIMUM: "Too few properties defined ({propertyCount}), minimum {minimum}",
        OBJECT_PROPERTIES_MAXIMUM: "Too many properties defined ({propertyCount}), maximum {maximum}",
        OBJECT_REQUIRED: "Missing required property: {key}",
        OBJECT_ADDITIONAL_PROPERTIES: "Additional properties not allowed",
        OBJECT_DEPENDENCY_KEY: "Dependency failed - key must exist: {missing} (due to key: {key})",
        // Array errors
        ARRAY_LENGTH_SHORT: "Array is too short ({length}), minimum {minimum}",
        ARRAY_LENGTH_LONG: "Array is too long ({length}), maximum {maximum}",
        ARRAY_UNIQUE: "Array items are not unique (indices {match1} and {match2})",
        ARRAY_ADDITIONAL_ITEMS: "Additional items not allowed",
        // Format errors
        FORMAT_CUSTOM: "Format validation failed ({message})",
        // Schema structure
        CIRCULAR_REFERENCE: "Circular $refs: {urls}",
        // Non-standard validation options
        UNKNOWN_PROPERTY: "Unknown property (not in schema)"
};

function ValidationError(code, message, dataPath, schemaPath, subErrors) {
        Error.call(this);
        if (code === undefined) {
                throw new Error ("No code supplied for error: "+ message);
        }
        this.message = message;
        this.code = code;
        this.dataPath = dataPath || "";
        this.schemaPath = schemaPath || "";
        this.subErrors = subErrors || null;

        var err = new Error(this.message);
        this.stack = err.stack || err.stacktrace;
        if (!this.stack) {
                try {
                        throw err;
                }
                catch(err) {
                        this.stack = err.stack || err.stacktrace;
                }
        }
}
ValidationError.prototype = Object.create(Error.prototype);
ValidationError.prototype.constructor = ValidationError;
ValidationError.prototype.name = 'ValidationError';

ValidationError.prototype.prefixWith = function (dataPrefix, schemaPrefix) {
        if (dataPrefix !== null) {
                dataPrefix = dataPrefix.replace(/~/g, "~0").replace(/\//g, "~1");
                this.dataPath = "/" + dataPrefix + this.dataPath;
        }
        if (schemaPrefix !== null) {
                schemaPrefix = schemaPrefix.replace(/~/g, "~0").replace(/\//g, "~1");
                this.schemaPath = "/" + schemaPrefix + this.schemaPath;
        }
        if (this.subErrors !== null) {
                for (var i = 0; i < this.subErrors.length; i++) {
                        this.subErrors[i].prefixWith(dataPrefix, schemaPrefix);
                }
        }
        return this;
};

function isTrustedUrl(baseUrl, testUrl) {
        if(testUrl.substring(0, baseUrl.length) === baseUrl){
                var remainder = testUrl.substring(baseUrl.length);
                if ((testUrl.length > 0 && testUrl.charAt(baseUrl.length - 1) === "/")
                        || remainder.charAt(0) === "#"
                        || remainder.charAt(0) === "?") {
                        return true;
                }
        }
        return false;
}

var languages = {};
function createApi(language) {
        var globalContext = new ValidatorContext();
        var currentLanguage = language || 'en';
        var api = {
                addFormat: function () {
                        globalContext.addFormat.apply(globalContext, arguments);
                },
                language: function (code) {
                        if (!code) {
                                return currentLanguage;
                        }
                        if (!languages[code]) {
                                code = code.split('-')[0]; // fall back to base language
                        }
                        if (languages[code]) {
                                currentLanguage = code;
                                return code; // so you can tell if fall-back has happened
                        }
                        return false;
                },
                addLanguage: function (code, messageMap) {
                        var key;
                        for (key in ErrorCodes) {
                                if (messageMap[key] && !messageMap[ErrorCodes[key]]) {
                                        messageMap[ErrorCodes[key]] = messageMap[key];
                                }
                        }
                        var rootCode = code.split('-')[0];
                        if (!languages[rootCode]) { // use for base language if not yet defined
                                languages[code] = messageMap;
                                languages[rootCode] = messageMap;
                        } else {
                                languages[code] = Object.create(languages[rootCode]);
                                for (key in messageMap) {
                                        if (typeof languages[rootCode][key] === 'undefined') {
                                                languages[rootCode][key] = messageMap[key];
                                        }
                                        languages[code][key] = messageMap[key];
                                }
                        }
                        return this;
                },
                freshApi: function (language) {
                        var result = createApi();
                        if (language) {
                                result.language(language);
                        }
                        return result;
                },
                validate: function (data, schema, checkRecursive, banUnknownProperties) {
                        var context = new ValidatorContext(globalContext, false, languages[currentLanguage], checkRecursive, banUnknownProperties);
                        if (typeof schema === "string") {
                                schema = {"$ref": schema};
                        }
                        context.addSchema("", schema);
                        var error = context.validateAll(data, schema, null, null, "");
                        if (!error && banUnknownProperties) {
                                error = context.banUnknownProperties();
                        }
                        this.error = error;
                        this.missing = context.missing;
                        this.valid = (error === null);
                        return this.valid;
                },
                validateResult: function () {
                        var result = {};
                        this.validate.apply(result, arguments);
                        return result;
                },
                validateMultiple: function (data, schema, checkRecursive, banUnknownProperties) {
                        var context = new ValidatorContext(globalContext, true, languages[currentLanguage], checkRecursive, banUnknownProperties);
                        if (typeof schema === "string") {
                                schema = {"$ref": schema};
                        }
                        context.addSchema("", schema);
                        context.validateAll(data, schema, null, null, "");
                        if (banUnknownProperties) {
                                context.banUnknownProperties();
                        }
                        var result = {};
                        result.errors = context.errors;
                        result.missing = context.missing;
                        result.valid = (result.errors.length === 0);
                        return result;
                },
                addSchema: function () {
                        return globalContext.addSchema.apply(globalContext, arguments);
                },
                getSchema: function () {
                        return globalContext.getSchema.apply(globalContext, arguments);
                },
                getSchemaMap: function () {
                        return globalContext.getSchemaMap.apply(globalContext, arguments);
                },
                getSchemaUris: function () {
                        return globalContext.getSchemaUris.apply(globalContext, arguments);
                },
                getMissingUris: function () {
                        return globalContext.getMissingUris.apply(globalContext, arguments);
                },
                dropSchemas: function () {
                        globalContext.dropSchemas.apply(globalContext, arguments);
                },
                reset: function () {
                        globalContext.reset();
                        this.error = null;
                        this.missing = [];
                        this.valid = true;
                },
                missing: [],
                error: null,
                valid: true,
                normSchema: normSchema,
                resolveUrl: resolveUrl,
                getDocumentUri: getDocumentUri,
                errorCodes: ErrorCodes
        };
        return api;
}

var tv4 = createApi();
tv4.addLanguage('en-gb', ErrorMessagesDefault);

//legacy property
tv4.tv4 = tv4;

if (typeof module !== 'undefined' && module.exports){
        module.exports = tv4;
}
else {
        global.tv4 = tv4;
}

})(this);