npm-polymer-elements/gold-cc-input/gold-cc-input.html

Polymer Elements package for npm

<!--
@license
Copyright (c) 2015 The Polymer Project Authors. All rights reserved.
This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
Code distributed by Google as part of the polymer project is also
subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
-->
<link rel="import" href="../polymer/polymer.html">
<link rel="import" href="../iron-flex-layout/iron-flex-layout.html">
<link rel="import" href="../paper-input/paper-input-behavior.html">
<link rel="import" href="../paper-input/paper-input-container.html">
<link rel="import" href="../paper-input/paper-input-error.html">
<link rel="import" href="../iron-input/iron-input.html">
<link rel="import" href="../iron-form-element-behavior/iron-form-element-behavior.html">
<link rel="import" href="../iron-icon/iron-icon.html">

<script src="cc-validator.js"></script>

<!--
`gold-cc-input` is a single-line text field with Material Design styling
for entering a credit card number. As the user types, the number will be
formatted by adding a space every 4 digits.

    <gold-cc-input></gold-cc-input>

It may include an optional label, which by default is "Card number".

    <gold-cc-input label="CC"></gold-cc-input>

### Validation

The input can detect whether a credit card number is valid, and the type
of credit card it is, using the Luhn checksum. See `http://jquerycreditcardvalidator.com/`
for more information.

The input can be automatically validated as the user is typing by using
the `auto-validate` and `required` attributes. For manual validation, the
element also has a `validate()` method, which returns the validity of the
input as well sets any appropriate error messages and styles.

See `Polymer.PaperInputBehavior` for more API docs.

### Styling

See `Polymer.PaperInputContainer` for a list of custom properties used to
style this element.

@group Gold Elements
@hero hero.svg
@demo demo/index.html
@class gold-cc-input
-->

<dom-module id="gold-cc-input">
  <style>
  :host {
    display: block;
  }

  /* Use a container so that when hiding the icon, the layout doesn't jump around. */
  .icon-container {
    margin-left: 10px;
    height: 27px;
  }

  iron-icon {
    --iron-icon-width: 40px;
    --iron-icon-height: 24px;
  }

  .container {
    @apply(--layout-horizontal);
  }
  </style>

  <template>

    <paper-input-container id="container"
        disabled$="[[disabled]]"
        no-label-float="[[noLabelFloat]]"
        always-float-label="[[_computeAlwaysFloatLabel(alwaysFloatLabel,placeholder)]]"
        invalid="[[invalid]]">

      <label hidden$="[[!label]]">[[label]]</label>

      <div class="container">
        <input is="iron-input" id="input"
            aria-labelledby$="[[_ariaLabelledBy]]"
            aria-describedby$="[[_ariaDescribedBy]]"
            bind-value="{{value}}"
            type="tel"
            maxlength="30"
            required$="[[required]]"
            allowed-pattern="[0-9 ]"
            prevent-invalid-input
            autocomplete="cc-number"
            name$="[[name]]"
            disabled$="[[disabled]]"
            invalid="{{invalid}}"
            autofocus$="[[autofocus]]"
            inputmode$="[[inputmode]]"
            placeholder$="[[placeholder]]"
            readonly$="[[readonly]]"
            size$="[[size]]">
        <div class="icon-container"><iron-icon id="icon"></iron-icon></div>
      </div>

      <template is="dom-if" if="[[errorMessage]]">
        <paper-input-error>[[errorMessage]]</paper-input-error>
      </template>

    </paper-input-container>
  </template>

</dom-module>

<script>
(function() {
  Polymer({

    is: 'gold-cc-input',

    behaviors: [
      Polymer.PaperInputBehavior,
      Polymer.IronValidatableBehavior,
      Polymer.IronFormElementBehavior
    ],

    properties: {
      /**
       * The label for this input.
       */
      label: {
        type: String,
        value: "Card number"
      },

      /**
       * The type of the credit card, if it is valid. Empty otherwise.
       */
      cardType: {
        type: String,
        notify: true
      },

      value: {
        observer: '_onValueChanged'
      }
    },

    observers: [
      '_onFocusedChanged(focused)'
    ],

    ready: function() {
      // If there's an initial input, validate it.
      if (this.value)
        this._handleAutoValidate();
    },

    /**
     * A handler that is called on input
     */
    _onValueChanged: function(value, oldValue) {
      // The initial property assignment is handled by `ready`.
      if (oldValue == undefined)
        return;

      var start = this.$.input.selectionStart;
      var previousCharASpace = value ? this.value.charAt(start - 1) == ' ' : false;

      var value = value.replace(/\s+/g, '');
      var formattedValue = '';
      for (var i = 0; i < value.length; i++) {
        // Add a space after every 4 characters.
        if ((i != 0) && (i % 4 == 0)) {
          formattedValue += ' ';
        }
        formattedValue += value[i];
      }
      this.updateValueAndPreserveCaret(formattedValue.trim());

      // If the character right before the selection is a newly inserted
      // space, we need to advance the selection to maintain the caret position.
      if (!previousCharASpace && this.value.charAt(start - 1) == ' ') {
        this.$.input.selectionStart = start+1;
        this.$.input.selectionEnd = start+1;
      }

      this._handleAutoValidate();
    },

    /**
     * Returns true if the element has a valid value, and sets the visual
     * error state.
     *
     * @return {boolean} Whether the input is currently valid or not.
     */
    validate: function() {
      // Empty, non-required input is valid.
      if (!this.required && this.value == '') {
        return true;
      }

      var result = CreditCardValidator.validate(this.value);
      var valid = result.valid && result.length_valid;
      this.cardType = valid ? result.card_type.name : '';

      // Update the container and its addons (i.e. the custom error-message).
      this.$.container.invalid = !valid;
      this.$.container.updateAddons({
        inputElement: this.$.input,
        value: this.value,
        invalid: !valid
      });

      // We don't have icons for all the card types.
      if (valid && result.card_type.icon) {
        this.$.icon.src = this.resolveUrl(result.card_type.icon);
        this.$.icon.alt = this.cardType;
        this.$.icon.hidden = false;
      } else {
        this.$.icon.src = null;
        this.$.icon.alt = '';
        this.$.icon.hidden = true;
      }

      return valid;
    },

    /**
     * Overidden from Polymer.IronControlState.
     */
    _onFocusedChanged: function(focused) {
      if (!focused) {
        this._handleAutoValidate();
      }
    }
  })

})();

</script>