/**
* General-purpose validator for ngModel.
* angular.js comes with several built-in validation mechanism for input fields (ngRequired, ngPattern etc.) but using
* an arbitrary validation function requires creation of a custom formatters and / or parsers.
* The ui-validate directive makes it easy to use any function(s) defined in scope as a validator function(s).
* A validator function will trigger validation on both model and input changes.
*
* @example
* @example
* @example
* @example
*
* @param ui-validate {string|object literal} If strings is passed it should be a scope's function to be used as a validator.
* If an object literal is passed a key denotes a validation error key while a value should be a validator function.
* In both cases validator function should take a value to validate as its argument and should return true/false indicating a validation result.
*/
angular.module('ui.directives').directive('uiValidate', function () {
return {
restrict: 'A',
require: 'ngModel',
link: function (scope, elm, attrs, ctrl) {
var validateFn, watch, validators = {},
validateExpr = scope.$eval(attrs.uiValidate);
if (!validateExpr) return;
if (angular.isString(validateExpr)) {
validateExpr = { validator: validateExpr };
}
angular.forEach(validateExpr, function (expression, key) {
validateFn = function (valueToValidate) {
if (scope.$eval(expression, { '$value' : valueToValidate })) {
ctrl.$setValidity(key, true);
return valueToValidate;
} else {
ctrl.$setValidity(key, false);
return undefined;
}
};
validators[key] = validateFn;
ctrl.$formatters.push(validateFn);
ctrl.$parsers.push(validateFn);
});
// Support for ui-validate-watch
if (attrs.uiValidateWatch) {
watch = scope.$eval(attrs.uiValidateWatch);
if (angular.isString(watch)) {
scope.$watch(watch, function(){
angular.forEach(validators, function(validatorFn, key){
validatorFn(ctrl.$modelValue);
});
});
} else {
angular.forEach(watch, function(expression, key){
scope.$watch(expression, function(){
validators[key](ctrl.$modelValue);
});
});
}
}
}
};
});