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

// A Set is a collection of unique elements.
var Set = new Class({

    initialize:

    function Set (elements)
    {
        this.entries = [];

        if (Array.isArray(elements))
        {
            for (var i = 0; i < elements.length; i++)
            {
                this.set(elements[i]);
            }
        }
    },

    set: function (value)
    {
        if (this.entries.indexOf(value) === -1)
        {
            this.entries.push(value);
        }

        return this;
    },

    get: function (property, value)
    {
        for (var i = 0; i < this.entries.length; i++)
        {
            var entry = this.entries[i];

            if (entry[property] === value)
            {
                return entry;
            }
        }
    },

    getArray: function ()
    {
        return this.entries.slice(0);
    },

    delete: function (value)
    {
        var index = this.entries.indexOf(value);

        if (index > -1)
        {
            this.entries.splice(index, 1);
        }

        return this;
    },

    dump: function ()
    {
        console.group('Set');

        for (var i = 0; i < this.entries.length; i++)
        {
            var entry = this.entries[i];
            console.log(entry);
        }

        console.groupEnd();
    },


    //  For when you know this Set will be modified during the iteration
    each: function (callback, callbackScope)
    {
        var i;
        var temp = this.entries.slice();
        var len = temp.length;

        if (callbackScope)
        {
            for (i = 0; i < len; i++)
            {
                if (callback.call(callbackScope, temp[i], i) === false)
                {
                    break;
                }
            }
        }
        else
        {
            for (i = 0; i < len; i++)
            {
                if (callback(temp[i], i) === false)
                {
                    break;
                }
            }
        }

        return this;
    },

    //  For when you absolutely know this Set won't be modified during the iteration
    iterate: function (callback, callbackScope)
    {
        var i;
        var len = this.entries.length;

        if (callbackScope)
        {
            for (i = 0; i < len; i++)
            {
                if (callback.call(callbackScope, this.entries[i], i) === false)
                {
                    break;
                }
            }
        }
        else
        {
            for (i = 0; i < len; i++)
            {
                if (callback(this.entries[i], i) === false)
                {
                    break;
                }
            }
        }

        return this;
    },

    iterateLocal: function (callbackKey)
    {
        var i;
        var args = [];

        for (i = 1; i < arguments.length; i++)
        {
            args.push(arguments[i]);
        }

        var len = this.entries.length;

        for (i = 0; i < len; i++)
        {
            var entry = this.entries[i];

            entry[callbackKey].apply(entry, args);
        }

        return this;
    },

    clear: function ()
    {
        this.entries.length = 0;

        return this;
    },

    contains: function (value)
    {
        return (this.entries.indexOf(value) > -1);
    },

    union: function (set)
    {
        var newSet = new Set();

        set.values.forEach(function (value)
        {
            newSet.add(value);
        });

        this.entries.forEach(function (value)
        {
            newSet.add(value);
        });

        return newSet;
    },

    intersect: function (set)
    {
        var newSet = new Set();

        this.entries.forEach(function (value)
        {
            if (set.contains(value))
            {
                newSet.add(value);
            }
        });

        return newSet;
    },

    difference: function (set)
    {
        var newSet = new Set();

        this.entries.forEach(function (value)
        {
            if (!set.contains(value))
            {
                newSet.add(value);
            }
        });

        return newSet;
    },

    size: {

        get: function ()
        {
            return this.entries.length;
        },

        set: function (value)
        {
            return this.entries.length = value;
        }

    }

});

module.exports = Set;