/**

 * enhancement.js

 * 

 * Collect & Create by Terence Chao

 */



// String Enhancement

String.prototype.trim = function() {

    return this.replace(/^\s+|\s+$|\n$|^\n/g, '');

};



String.prototype.escapeMarkup = function() {

    var character = {

        '<': '&lt;',

        '>': '&gt;',

        '&': '&amp;',

        '"': '&quot;'

    };

    return this.replace(/[<>&"]/g, function (c) {

        return character[c];

    });

};



String.prototype.isPartOf = function(str) {

    var re = new RegExp( '(^|\\s)' + this + '(^|\\s)' );

    return re.test( str );

};



// Array Enhancement

Array.prototype.foreach = function(fn) {

    for( var i=0; i<this.length; i++) {

        fn.call( this[i] );

    } // for

};



// Function Enhancement

Function.prototype.method = function(name, fn) {

    this.prototype[name] = fn;

};



// Interface class

var Interface = function(name, methods) {

    if(arguments.length != 2) {

        throw new Error( 'Interfac constructor called with ' + arguments.length + 

        ' arguments, but expected exactly 2' );

    } //if

    

    this.name = name;

    this.methods = [];

    

    for( var i=0, len=methods.length; i<len; i++) {

        if( typeof methods[i] !== 'string' ) {

            throw new Error( 'Interface constructor expects method names to be ' +

            'passed in as a string.' );

        } // if

        this.methods.push( methods[i] );

    } // for

};



// from John Resig's book

// Static class method to ensure implements interface methods

Interface.ensureImplements = function(object) {

    if(arguments.length < 2) {

        throw new Error( 'Function Interface.ensureImplements called with ' + arguments.length +

        ' arguments, but expected at least 2.' );

    } // if

    

    for( var i=1, len=arguments.length; i<len; i++) {

        var interface = arguments[i];

        if(interface.constructor !== Interface) {

            throw new Error( 'Function Interface.ensureImplements expects arguments ' +

            'two and above to be instances of Interface' );

        } // if

        

        for( var j=0, methodsLen=interface.methods.length; j<methodsLen; j++) {

            var method = interface.methods[j];

            if( !object[methods] || typeof object[method] !== 'function' ) {

                throw new Error( 'Function Interface.ensureImplements: object ' +

                'does not implement the ' + interface.name +

                ' interface. Method ' + method + ' was not found.' );

            } // if

        } // for

    } // for

};



// Form Validation (from John Resig)

// CSS Class based JavaScript Form Validation

var errMsg = {

    // check for required field

    required: {

        msg: '這個欄位為必填欄位。',

        test: function( obj ) {

            return obj.value.length > 0;

        }

    },

    notrel: {

        msg: '欄位值不合法',

        test: function( obj ) {

            return !obj.value || !( obj.value === obj.getAttribute( 'rel' ) );

        }

    },

    year: {

        msg: '輸入年格式錯誤(請輸入西元年)',

        test: function( obj ) {

            return !obj.value || /^\d{4}$/.test( obj.value );

        }

    },

    month: {

        msg: '輸入月份格式錯誤(請輸入1-12)',

        test: function( obj ) {

            return !obj.value || /^[1-9]{1}$|^1[0-2]{1}$/.test( obj.value );

        }

    },

    day: {

        msg: '輸入日期格式錯誤(請輸入1-31)',

        test: function( obj ) {

            return !obj.value || /^[1-9]{1}$|^[1-2][0-9]{1}$|^3[0-1]{1}$/.test( obj.value );

        }

    },

    creditcardtype: {

        msg: '請選擇信用卡類別',

        test: function( obj ) {

            return !obj.value || obj.value === 'AE' || obj.value === 'VISA' || obj.value === 'MASTER';

        }

    },

    equmaxlen: {

        msg: '輸入值過長',

        test: function( obj ) {

            // for ie6 getAttribute('maxlength') is number but not true in ff and ie8

            return !obj.value || obj.value.length.toString() === obj.getAttribute('maxlength').toString();

        }

    },

    sameasref: {

        msg: '兩個欄位值必須相同',

        test: function( obj ) {

            if( obj.getAttribute('ref') === null || document.getElementById( obj.getAttribute('ref') ) === null ) {

                return false;

            } else {

                return !obj.value || obj.value === document.getElementById( obj.getAttribute('ref') ).value;

            }

        }

    },

    mobiletw: {

        msg: '行動電話格式錯誤',

        test: function( obj ) {

            if( obj.value !== undefined && obj.value !== '' ) {

                return /^09\d{8}$/.test( obj.value );

            }

            return true;

        }

    }

};



function validateForm( form, errlist, errstyle ) {

    var valid = true;

    

    for( var i=0; i<form.elements.length; i++ ) {

        if( ! validateField( form.elements[i], errlist, errstyle ) ) {

            valid = false;

        } // if

    } // for

    

    return valid;

};



function validateField( elem, errlist, errstyle ) {

    var errors = [];

    var name;

    var re;

    

    for( name in errMsg ) {

        re = new RegExp( '(^|\\s)' + name + '(\\s|$)' );

        if( re.test( elem.className ) && !errMsg[name].test( elem ) ) {

            errors.push( elem.getAttribute( 'alt' ) + ': ' + errMsg[name].msg );

            elem.setAttribute('style', errstyle);

        } // if

    } // for

    

    if(errors.length>0) {

        errors.foreach( function() {

            errlist.push( this + '\n' );

        });

    }

    

    return !(errors.length > 0);

};



function setFormInputStyle( form, style, escapetype ) {

    for( var i=0; i<form.elements.length; i++ ) {

        if( form.elements[i].getAttribute('type') !== null && 

            !form.elements[i].getAttribute('type').isPartOf(escapetype) ) {

            form.elements[i].setAttribute('style', style);

        }

    } // for

};