/*!
 * Microsoft Dynamic Proto Utility, 1.1.6
 * Copyright (c) Microsoft and contributors. All rights reserved.
 */
define((function () { 'use strict';

    /**
     * Constant string defined to support minimization
     * @ignore
     */
    var Constructor = 'constructor';
    /**
     * Constant string defined to support minimization
     * @ignore
     */
    var Prototype = 'prototype';
    /**
     * Constant string defined to support minimization
     * @ignore
     */
    var strFunction = 'function';
    /**
     * Used to define the name of the instance function lookup table
     * @ignore
     */
    var DynInstFuncTable = '_dynInstFuncs';
    /**
     * Name used to tag the dynamic prototype function
     * @ignore
     */
    var DynProxyTag = '_isDynProxy';
    /**
     * Name added to a prototype to define the dynamic prototype "class" name used to lookup the function table
     * @ignore
     */
    var DynClassName = '_dynClass';
    /**
     * Prefix added to the classname to avoid any name clashes with other instance level properties
     * @ignore
     */
    var DynClassNamePrefix = '_dynCls$';
    /**
     * A tag which is used to check if we have already to attempted to set the instance function if one is not present
     * @ignore
     */
    var DynInstChkTag = '_dynInstChk';
    /**
     * A tag which is used to check if we are allows to try and set an instance function is one is not present. Using the same
     * tag name as the function level but a different const name for readability only.
     */
    var DynAllowInstChkTag = DynInstChkTag;
    /**
     * The global (imported) instances where the global performance options are stored
     */
    var DynProtoDefaultOptions = '_dfOpts';
    /**
     * Value used as the name of a class when it cannot be determined
     * @ignore
     */
    var UnknownValue = '_unknown_';
    /**
     * Constant string defined to support minimization
     * @ignore
     */
    var str__Proto = "__proto__";
    /**
     * The polyfill version of __proto__ so that it doesn't cause issues for anyone not expecting it to exist
     */
    var DynProtoBaseProto = "_dyn" + str__Proto;
    /**
     * Track the current prototype for IE8 as you can't look back to get the prototype
     */
    var DynProtoCurrent = "_dynInstProto";
    /**
     * Constant string defined to support minimization
     * @ignore
     */
    var strUseBaseInst = 'useBaseInst';
    /**
     * Constant string defined to support minimization
     * @ignore
     */
    var strSetInstFuncs = 'setInstFuncs';
    var Obj = Object;
    /**
     * Pre-lookup to check if we are running on a modern browser (i.e. not IE8)
     * @ignore
     */
    var _objGetPrototypeOf = Obj["getPrototypeOf"];
    /**
     * Pre-lookup to check for the existence of this function
     */
    var _objGetOwnProps = Obj["getOwnPropertyNames"];
    /**
     * Internal Global used to generate a unique dynamic class name, every new class will increase this value
     * @ignore
     */
    var _dynamicNames = 0;
    /**
     * Helper to check if the object contains a property of the name
     * @ignore
     */
    function _hasOwnProperty(obj, prop) {
        return obj && Obj[Prototype].hasOwnProperty.call(obj, prop);
    }
    /**
     * Helper used to check whether the target is an Object prototype or Array prototype
     * @ignore
     */
    function _isObjectOrArrayPrototype(target) {
        return target && (target === Obj[Prototype] || target === Array[Prototype]);
    }
    /**
     * Helper used to check whether the target is an Object prototype, Array prototype or Function prototype
     * @ignore
     */
    function _isObjectArrayOrFunctionPrototype(target) {
        return _isObjectOrArrayPrototype(target) || target === Function[Prototype];
    }
    /**
     * Helper used to get the prototype of the target object as getPrototypeOf is not available in an ES3 environment.
     * @ignore
     */
    function _getObjProto(target) {
        var newProto;
        if (target) {
            // This method doesn't exist in older browsers (e.g. IE8)
            if (_objGetPrototypeOf) {
                return _objGetPrototypeOf(target);
            }
            var curProto = target[str__Proto] || target[Prototype] || (target[Constructor] ? target[Constructor][Prototype] : null);
            // Using the pre-calculated value as IE8 doesn't support looking up the prototype of a prototype and thus fails for more than 1 base class
            newProto = target[DynProtoBaseProto] || curProto;
            if (!_hasOwnProperty(target, DynProtoBaseProto)) {
                // As this prototype doesn't have this property then this is from an inherited class so newProto is the base to return so save it
                // so we can look it up value (which for a multiple hierarchy dynamicProto will be the base class)
                delete target[DynProtoCurrent]; // Delete any current value allocated to this instance so we pick up the value from prototype hierarchy
                newProto = target[DynProtoBaseProto] = target[DynProtoCurrent] || target[DynProtoBaseProto];
                target[DynProtoCurrent] = curProto;
            }
        }
        return newProto;
    }
    /**
     * Helper to get the properties of an object, including none enumerable ones as functions on a prototype in ES6
     * are not enumerable.
     * @param target
     */
    function _forEachProp(target, func) {
        var props = [];
        if (_objGetOwnProps) {
            props = _objGetOwnProps(target);
        }
        else {
            for (var name_1 in target) {
                if (typeof name_1 === "string" && _hasOwnProperty(target, name_1)) {
                    props.push(name_1);
                }
            }
        }
        if (props && props.length > 0) {
            for (var lp = 0; lp < props.length; lp++) {
                func(props[lp]);
            }
        }
    }
    /**
     * Helper function to check whether the provided function name is a potential candidate for dynamic
     * callback and prototype generation.
     * @param target The target object, may be a prototype or class object
     * @param funcName The function name
     * @param skipOwn Skips the check for own property
     * @ignore
     */
    function _isDynamicCandidate(target, funcName, skipOwn) {
        return (funcName !== Constructor && typeof target[funcName] === strFunction && (skipOwn || _hasOwnProperty(target, funcName)));
    }
    /**
     * Helper to throw a TypeError exception
     * @param message the message
     * @ignore
     */
    function _throwTypeError(message) {
        throw new TypeError("DynamicProto: " + message);
    }
    /**
     * Returns a collection of the instance functions that are defined directly on the thisTarget object, it does
     * not return any inherited functions
     * @param thisTarget The object to get the instance functions from
     * @ignore
     */
    function _getInstanceFuncs(thisTarget) {
        // Get the base proto
        var instFuncs = {};
        // Save any existing instance functions
        _forEachProp(thisTarget, function (name) {
            // Don't include any dynamic prototype instances - as we only want the real functions
            if (!instFuncs[name] && _isDynamicCandidate(thisTarget, name, false)) {
                // Create an instance callback for passing the base function to the caller
                instFuncs[name] = thisTarget[name];
            }
        });
        return instFuncs;
    }
    /**
     * Returns whether the value is included in the array
     * @param values The array of values
     * @param value  The value
     */
    function _hasVisited(values, value) {
        for (var lp = values.length - 1; lp >= 0; lp--) {
            if (values[lp] === value) {
                return true;
            }
        }
        return false;
    }
    /**
     * Returns an object that contains callback functions for all "base/super" functions, this is used to "save"
     * enabling calling super.xxx() functions without requiring that the base "class" has defined a prototype references
     * @param target The current instance
     * @ignore
     */
    function _getBaseFuncs(classProto, thisTarget, instFuncs, useBaseInst) {
        function _instFuncProxy(target, funcHost, funcName) {
            var theFunc = funcHost[funcName];
            if (theFunc[DynProxyTag] && useBaseInst) {
                // grab and reuse the hosted looking function (if available) otherwise the original passed function
                var instFuncTable = target[DynInstFuncTable] || {};
                if (instFuncTable[DynAllowInstChkTag] !== false) {
                    theFunc = (instFuncTable[funcHost[DynClassName]] || {})[funcName] || theFunc;
                }
            }
            return function () {
                // eslint-disable-next-line prefer-rest-params
                return theFunc.apply(target, arguments);
            };
        }
        // Start creating a new baseFuncs by creating proxies for the instance functions (as they may get replaced)
        var baseFuncs = {};
        _forEachProp(instFuncs, function (name) {
            // Create an instance callback for passing the base function to the caller
            baseFuncs[name] = _instFuncProxy(thisTarget, instFuncs, name);
        });
        // Get the base prototype functions
        var baseProto = _getObjProto(classProto);
        var visited = [];
        // Don't include base object functions for Object, Array or Function
        while (baseProto && !_isObjectArrayOrFunctionPrototype(baseProto) && !_hasVisited(visited, baseProto)) {
            // look for prototype functions
            _forEachProp(baseProto, function (name) {
                // Don't include any dynamic prototype instances - as we only want the real functions
                // For IE 7/8 the prototype lookup doesn't provide the full chain so we need to bypass the 
                // hasOwnProperty check we get all of the methods, main difference is that IE7/8 doesn't return
                // the Object prototype methods while bypassing the check
                if (!baseFuncs[name] && _isDynamicCandidate(baseProto, name, !_objGetPrototypeOf)) {
                    // Create an instance callback for passing the base function to the caller
                    baseFuncs[name] = _instFuncProxy(thisTarget, baseProto, name);
                }
            });
            // We need to find all possible functions that might be overloaded by walking the entire prototype chain
            // This avoids the caller from needing to check whether it's direct base class implements the function or not
            // by walking the entire chain it simplifies the usage and issues from upgrading any of the base classes.
            visited.push(baseProto);
            baseProto = _getObjProto(baseProto);
        }
        return baseFuncs;
    }
    function _getInstFunc(target, funcName, proto, currentDynProtoProxy) {
        var instFunc = null;
        // We need to check whether the class name is defined directly on this prototype otherwise
        // it will walk the proto chain and return any parent proto classname.
        if (target && _hasOwnProperty(proto, DynClassName)) {
            var instFuncTable = target[DynInstFuncTable] || {};
            instFunc = (instFuncTable[proto[DynClassName]] || {})[funcName];
            if (!instFunc) {
                // Avoid stack overflow from recursive calling the same function
                _throwTypeError("Missing [" + funcName + "] " + strFunction);
            }
            // We have the instance function, lets check it we can speed up further calls
            // by adding the instance function back directly on the instance (avoiding the dynamic func lookup)
            if (!instFunc[DynInstChkTag] && instFuncTable[DynAllowInstChkTag] !== false) {
                // If the instance already has an instance function we can't replace it
                var canAddInst = !_hasOwnProperty(target, funcName);
                // Get current prototype
                var objProto = _getObjProto(target);
                var visited = [];
                // Lookup the function starting at the top (instance level prototype) and traverse down, if the first matching function
                // if nothing is found or if the first hit is a dynamic proto instance then we can safely add an instance shortcut
                while (canAddInst && objProto && !_isObjectArrayOrFunctionPrototype(objProto) && !_hasVisited(visited, objProto)) {
                    var protoFunc = objProto[funcName];
                    if (protoFunc) {
                        canAddInst = (protoFunc === currentDynProtoProxy);
                        break;
                    }
                    // We need to find all possible initial functions to ensure that we don't bypass a valid override function
                    visited.push(objProto);
                    objProto = _getObjProto(objProto);
                }
                try {
                    if (canAddInst) {
                        // This instance doesn't have an instance func and the class hierarchy does have a higher level prototype version
                        // so it's safe to directly assign for any subsequent calls (for better performance)
                        target[funcName] = instFunc;
                    }
                    // Block further attempts to set the instance function for any
                    instFunc[DynInstChkTag] = 1;
                }
                catch (e) {
                    // Don't crash if the object is readonly or the runtime doesn't allow changing this
                    // And set a flag so we don't try again for any function
                    instFuncTable[DynAllowInstChkTag] = false;
                }
            }
        }
        return instFunc;
    }
    function _getProtoFunc(funcName, proto, currentDynProtoProxy) {
        var protoFunc = proto[funcName];
        // Check that the prototype function is not a self reference -- try to avoid stack overflow!
        if (protoFunc === currentDynProtoProxy) {
            // It is so lookup the base prototype
            protoFunc = _getObjProto(proto)[funcName];
        }
        if (typeof protoFunc !== strFunction) {
            _throwTypeError("[" + funcName + "] is not a " + strFunction);
        }
        return protoFunc;
    }
    /**
     * Add the required dynamic prototype methods to the the class prototype
     * @param proto - The class prototype
     * @param className - The instance classname
     * @param target - The target instance
     * @param baseInstFuncs - The base instance functions
     * @param setInstanceFunc - Flag to allow prototype function to reset the instance function if one does not exist
     * @ignore
     */
    function _populatePrototype(proto, className, target, baseInstFuncs, setInstanceFunc) {
        function _createDynamicPrototype(proto, funcName) {
            var dynProtoProxy = function () {
                // Use the instance or prototype function
                var instFunc = _getInstFunc(this, funcName, proto, dynProtoProxy) || _getProtoFunc(funcName, proto, dynProtoProxy);
                // eslint-disable-next-line prefer-rest-params
                return instFunc.apply(this, arguments);
            };
            // Tag this function as a proxy to support replacing dynamic proxy elements (primary use case is for unit testing
            // via which can dynamically replace the prototype function reference)
            dynProtoProxy[DynProxyTag] = 1;
            return dynProtoProxy;
        }
        if (!_isObjectOrArrayPrototype(proto)) {
            var instFuncTable = target[DynInstFuncTable] = target[DynInstFuncTable] || {};
            var instFuncs_1 = instFuncTable[className] = (instFuncTable[className] || {}); // fetch and assign if as it may not exist yet
            // Set whether we are allow to lookup instances, if someone has set to false then do not re-enable
            if (instFuncTable[DynAllowInstChkTag] !== false) {
                instFuncTable[DynAllowInstChkTag] = !!setInstanceFunc;
            }
            _forEachProp(target, function (name) {
                // Only add overridden functions
                if (_isDynamicCandidate(target, name, false) && target[name] !== baseInstFuncs[name]) {
                    // Save the instance Function to the lookup table and remove it from the instance as it's not a dynamic proto function
                    instFuncs_1[name] = target[name];
                    delete target[name];
                    // Add a dynamic proto if one doesn't exist or if a prototype function exists and it's not a dynamic one
                    if (!_hasOwnProperty(proto, name) || (proto[name] && !proto[name][DynProxyTag])) {
                        proto[name] = _createDynamicPrototype(proto, name);
                    }
                }
            });
        }
    }
    /**
     * Checks whether the passed prototype object appears to be correct by walking the prototype hierarchy of the instance
     * @param classProto The class prototype instance
     * @param thisTarget The current instance that will be checked whether the passed prototype instance is in the hierarchy
     * @ignore
     */
    function _checkPrototype(classProto, thisTarget) {
        // This method doesn't existing in older browsers (e.g. IE8)
        if (_objGetPrototypeOf) {
            // As this is primarily a coding time check, don't bother checking if running in IE8 or lower
            var visited = [];
            var thisProto = _getObjProto(thisTarget);
            while (thisProto && !_isObjectArrayOrFunctionPrototype(thisProto) && !_hasVisited(visited, thisProto)) {
                if (thisProto === classProto) {
                    return true;
                }
                // This avoids the caller from needing to check whether it's direct base class implements the function or not
                // by walking the entire chain it simplifies the usage and issues from upgrading any of the base classes.
                visited.push(thisProto);
                thisProto = _getObjProto(thisProto);
            }
            return false;
        }
        // If objGetPrototypeOf doesn't exist then just assume everything is ok.
        return true;
    }
    /**
     * Gets the current prototype name using the ES6 name if available otherwise falling back to a use unknown as the name.
     * It's not critical for this to return a name, it's used to decorate the generated unique name for easier debugging only.
     * @param target
     * @param unknownValue
     * @ignore
     */
    function _getObjName(target, unknownValue) {
        if (_hasOwnProperty(target, Prototype)) {
            // Look like a prototype
            return target.name || unknownValue || UnknownValue;
        }
        return (((target || {})[Constructor]) || {}).name || unknownValue || UnknownValue;
    }
    /**
     * Helper function when creating dynamic (inline) functions for classes, this helper performs the following tasks :-
     * - Saves references to all defined base class functions
     * - Calls the delegateFunc with the current target (this) and a base object reference that can be used to call all "super" functions.
     * - Will populate the class prototype for all overridden functions to support class extension that call the prototype instance.
     * Callers should use this helper when declaring all function within the constructor of a class, as mentioned above the delegateFunc is
     * passed both the target "this" and an object that can be used to call any base (super) functions, using this based object in place of
     * super.XXX() (which gets expanded to _super.prototype.XXX()) provides a better minification outcome and also ensures the correct "this"
     * context is maintained as TypeScript creates incorrect references using super.XXXX() for dynamically defined functions i.e. Functions
     * defined in the constructor or some other function (rather than declared as complete typescript functions).
     * ### Usage
     * ```typescript
     * import dynamicProto from "@microsoft/dynamicproto-js";
     * class ExampleClass extends BaseClass {
     *     constructor() {
     *         dynamicProto(ExampleClass, this, (_self, base) => {
     *             // This will define a function that will be converted to a prototype function
     *             _self.newFunc = () => {
     *                 // Access any "this" instance property
     *                 if (_self.someProperty) {
     *                     ...
     *                 }
     *             }
     *             // This will define a function that will be converted to a prototype function
     *             _self.myFunction = () => {
     *                 // Access any "this" instance property
     *                 if (_self.someProperty) {
     *                     // Call the base version of the function that we are overriding
     *                     base.myFunction();
     *                 }
     *                 ...
     *             }
     *             _self.initialize = () => {
     *                 ...
     *             }
     *             // Warnings: While the following will work as _self is simply a reference to
     *             // this, if anyone overrides myFunction() the overridden will be called first
     *             // as the normal JavaScript method resolution will occur and the defined
     *             // _self.initialize() function is actually gets removed from the instance and
     *             // a proxy prototype version is created to reference the created method.
     *             _self.initialize();
     *         });
     *     }
     * }
     * ```
     * @typeparam DPType This is the generic type of the class, used to keep intellisense valid
     * @typeparam DPCls The type that contains the prototype of the current class
     * @param theClass - This is the current class instance which contains the prototype for the current class
     * @param target - The current "this" (target) reference, when the class has been extended this.prototype will not be the 'theClass' value.
     * @param delegateFunc - The callback function (closure) that will create the dynamic function
     * @param options - Additional options to configure how the dynamic prototype operates
     */
    function dynamicProto(theClass, target, delegateFunc, options) {
        // Make sure that the passed theClass argument looks correct
        if (!_hasOwnProperty(theClass, Prototype)) {
            _throwTypeError("theClass is an invalid class definition.");
        }
        // Quick check to make sure that the passed theClass argument looks correct (this is a common copy/paste error)
        var classProto = theClass[Prototype];
        if (!_checkPrototype(classProto, target)) {
            _throwTypeError("[" + _getObjName(theClass) + "] is not in class hierarchy of [" + _getObjName(target) + "]");
        }
        var className = null;
        if (_hasOwnProperty(classProto, DynClassName)) {
            // Only grab the class name if it's defined on this prototype (i.e. don't walk the prototype chain)
            className = classProto[DynClassName];
        }
        else {
            // As not all browser support name on the prototype creating a unique dynamic one if we have not already
            // assigned one, so we can use a simple string as the lookup rather than an object for the dynamic instance
            // function table lookup.
            className = DynClassNamePrefix + _getObjName(theClass, "_") + "$" + _dynamicNames;
            _dynamicNames++;
            classProto[DynClassName] = className;
        }
        var perfOptions = dynamicProto[DynProtoDefaultOptions];
        var useBaseInst = !!perfOptions[strUseBaseInst];
        if (useBaseInst && options && options[strUseBaseInst] !== undefined) {
            useBaseInst = !!options[strUseBaseInst];
        }
        // Get the current instance functions
        var instFuncs = _getInstanceFuncs(target);
        // Get all of the functions for any base instance (before they are potentially overridden)
        var baseFuncs = _getBaseFuncs(classProto, target, instFuncs, useBaseInst);
        // Execute the delegate passing in both the current target "this" and "base" function references
        // Note casting the same type as we don't actually have the base class here and this will provide some intellisense support
        delegateFunc(target, baseFuncs);
        // Don't allow setting instance functions for older IE instances
        var setInstanceFunc = !!_objGetPrototypeOf && !!perfOptions[strSetInstFuncs];
        if (setInstanceFunc && options) {
            setInstanceFunc = !!options[strSetInstFuncs];
        }
        // Populate the Prototype for any overridden instance functions
        _populatePrototype(classProto, className, target, instFuncs, setInstanceFunc !== false);
    }
    /**
     * Exposes the default global options to allow global configuration, if the global values are disabled these will override
     * any passed values. This is primarily exposed to support unit-testing without the need for individual classes to expose
     * their internal usage of dynamic proto.
     */
    var perfDefaults = {
        setInstFuncs: true,
        useBaseInst: true
    };
    // And expose for testing
    dynamicProto[DynProtoDefaultOptions] = perfDefaults;

    return dynamicProto;

}));
//# sourceMappingURL=dynamicproto-js.js.map
