<?php

/**
 * Class MC4WP_Form_Element
 *
 * @since 3.0
 * @ignore
 * @access private
 */
class MC4WP_Form_Element
{

    /**
     * @var string
     */
    public $ID;

    /**
     * @var MC4WP_Form
     */
    public $form;

    /**
     * @var array
     *
     * Can be used to set element-specific config settings. Accepts the following keys.
     *
     * - lists: Customized number of Mailchimp list ID's to subscribe to.
     * - email_type: The email type
     */
    public $config = array();

    /**
     * @var bool
     */
    public $is_submitted = false;

    /**
     * @param MC4WP_Form $form
     * @param string $ID
     * @param $config array
     */
    public function __construct(MC4WP_Form $form, $ID, $config = array())
    {
        $this->form = $form;
        $this->ID = $ID;
        $this->config = $config;

        $this->is_submitted = $this->form->is_submitted
                              && $this->form->config['element_id'] == $this->ID;
    }


    /**
     * @return string
     */
    protected function get_visible_fields()
    {
        $content = $this->form->content;
        $form = $this->form;
        $element = $this;

        /**
         * Filters the HTML for the form fields.
         *
         * Use this filter to add custom HTML to a form programmatically
         *
         * @param string $content
         * @param MC4WP_Form $form
         * @param MC4WP_Form_Element $element
         * @since 2.0
         */
        $visible_fields = (string) apply_filters('mc4wp_form_content', $content, $form, $element);

        return $visible_fields;
    }

    /**
     * @return string
     */
    protected function get_hidden_fields()
    {

        // hidden fields
        $hidden_fields =  '<label style="display: none !important;">' . __('Leave this field empty if you\'re human:', 'mailchimp-for-wp') . ' ' . '<input type="text" name="_mc4wp_honeypot" value="" tabindex="-1" autocomplete="off" /></label>';
        $hidden_fields .= '<input type="hidden" name="_mc4wp_timestamp" value="'. time() . '" />';
        $hidden_fields .= '<input type="hidden" name="_mc4wp_form_id" value="'. esc_attr($this->form->ID) .'" />';
        $hidden_fields .= '<input type="hidden" name="_mc4wp_form_element_id" value="'. esc_attr($this->ID) .'" />';

        // was "lists" parameter passed in shortcode arguments?
        if (! empty($this->config['lists'])) {
            $lists_string = is_array($this->config['lists']) ? join(',', $this->config['lists']) : $this->config['lists'];
            $hidden_fields .= '<input type="hidden" name="_mc4wp_lists" value="'. esc_attr($lists_string) . '" />';
        }

        // was "lists" parameter passed in shortcode arguments?
        if (! empty($this->config['email_type'])) {
            $hidden_fields .= '<input type="hidden" name="_mc4wp_email_type" value="'. esc_attr($this->config['email_type']) . '" />';
        }

        return (string) $hidden_fields;
    }

    /**
     * Get HTML string for a notice, including wrapper element.
     *
     * @param MC4WP_Form_Notice $notice
     *
     * @return string
     */
    protected function get_notice_html(MC4WP_Form_Notice $notice)
    {
        if ($notice->text === '') {
            return '';
        }

        $html = sprintf('<div class="mc4wp-alert mc4wp-%s"><p>%s</p></div>', esc_attr($notice->type), $notice->text);
        return $html;
    }

    /**
     * Gets the form response string
     *
     * @param boolean $force_show
     * @return string
     */
    public function get_response_html($force_show = false)
    {
        $html = '';
        $form = $this->form;

        if ($this->is_submitted || $force_show) {
            foreach ($this->form->notices as $notice) {
                $html .= $this->get_notice_html($notice);
            }
        }

        /**
         * Filter the form response HTML
         *
         * Use this to add your own HTML to the form response. The form instance is passed to the callback function.
         *
         * @since 3.0
         *
         * @param string $html The complete HTML string of the response, excluding the wrapper element.
         * @param MC4WP_Form $form The form object
         */
        $html = (string) apply_filters('mc4wp_form_response_html', $html, $form);

        // wrap entire response in div, regardless of a form was submitted
        $html = '<div class="mc4wp-response">' . $html . '</div>';
        return $html;
    }

    /**
     * @return string
     */
    protected function get_response_position()
    {
        $position = 'after';
        $form = $this->form;

        // check if content contains {response} tag
        if (stripos($this->form->content, '{response}') !== false) {
            return '';
        }

        /**
         * Filters the position for the form response.
         *
         * Valid values are "before" and "after". Will have no effect if `{response}` is used in the form content.
         *
         * @param string $position
         * @param MC4WP_Form $form
         * @since 2.0
         */
        $response_position = (string) apply_filters('mc4wp_form_response_position', $position, $form);

        return $response_position;
    }

    /**
     * Get HTML to be added _before_ the HTML of the form fields.
     *
     * @return string
     */
    protected function get_html_before_fields()
    {
        $html = '';
        $form = $this->form;

        /**
         * Filters the HTML before the form fields.
         *
         * @param string $html
         * @param MC4WP_Form $form
         * @ignore
         */
        $html = (string) apply_filters('mc4wp_form_before_fields', $html, $form);

        if ($this->get_response_position() === 'before') {
            $html = $html . $this->get_response_html();
        }

        return $html;
    }

    /**
     * Get HTML to be added _after_ the HTML of the form fields.
     *
     * @return string
     */
    protected function get_html_after_fields()
    {
        $html = '';
        $form = $this->form;

        /**
         * Filters the HTML after the form fields.
         *
         * @param string $html
         * @param MC4WP_Form $form
         * @ignore
         */
        $html = (string) apply_filters('mc4wp_form_after_fields', $html, $form);

        if ($this->get_response_position() === 'after') {
            $html = $this->get_response_html() . $html;
        }

        return $html;
    }

    /**
     * Get all HTMl attributes for the form element
     *
     * @return string
     */
    protected function get_form_element_attributes()
    {
        $form = $this;
        $form_action_attribute = null;

        $attributes = array(
            'id' => $this->ID,
            'class' => $this->get_css_classes()
        );

        /**
         * Filters the `action` attribute of the `<form>` element.
         *
         * Defaults to `null`, which means no `action` attribute will be printed.
         *
         * @param string $form_action_attribute
         * @param MC4WP_Form $form
         */
        $form_action_attribute = apply_filters('mc4wp_form_action', $form_action_attribute, $form);
        if (is_string($form_action_attribute)) {
            $attributes['action'] = $form_action_attribute;
        }

        /**
         * Filters all attributes to be added to the `<form>` element
         *
         * @param array $attributes Key-value pairs of attributes.
         * @param MC4WP_Form $form
         */
        $attributes = (array) apply_filters('mc4wp_form_element_attributes', $attributes, $form);

        // hardcoded attributes, can not be changed.
        $attributes['method'] = 'post';
        $attributes['data-id'] = $this->form->ID;
        $attributes['data-name'] = $this->form->name;

        // build string of key="value" from array
        $string = '';
        foreach ($attributes as $name => $value) {
            $string .= sprintf('%s="%s" ', $name, esc_attr($value));
        }

        return $string;
    }

    /**
     * @param array|null $config Use this to override the configuration for this form element
     * @return string
     */
    public function generate_html(array $config = null)
    {
        if ($config) {
            $this->config = $config;
        }

        // return empty string if form is in trash
        if ($this->form->status !== 'publish') {
            return '';
        }

        // Start building content string
        $opening_html = '<!-- Mailchimp for WordPress v' . MC4WP_VERSION . ' - https://wordpress.org/plugins/mailchimp-for-wp/ -->';
        $opening_html .= '<form '. $this->get_form_element_attributes() .'>';
        $before_fields = $this->get_html_before_fields();
        $fields = '';
        $after_fields = $this->get_html_after_fields();
        $closing_html = '</form><!-- / Mailchimp for WordPress Plugin -->';

        if (! $this->is_submitted
            || ! $this->form->settings['hide_after_success']
            || $this->form->has_errors()) {

            // add HTML for fields + wrapper element.
            $fields = '<div class="mc4wp-form-fields">' .
                $this->get_visible_fields() .
                '</div>' .
                $this->get_hidden_fields();
        }

        // concatenate everything
        $output = $opening_html .
                  $before_fields .
                  $fields .
                  $after_fields .
                  $closing_html;

        return $output;
    }

    /**
     * Get a space separated list of CSS classes for this form
     *
     * @return string
     */
    protected function get_css_classes()
    {
        $classes = array();
        $form = $this->form;

        $classes[] = 'mc4wp-form';
        $classes[] = 'mc4wp-form-' . $form->ID;

        // Add form classes if this specific form element was submitted
        if ($this->is_submitted) {
            $classes[] = 'mc4wp-form-submitted';

            if (! $form->has_errors()) {
                $classes[] = 'mc4wp-form-success';
            } else {
                $classes[] = 'mc4wp-form-error';
            }
        }

        // add class for CSS targeting in custom stylesheets
        if (! empty($form->settings['css'])) {
            if (strpos($form->settings['css'], 'theme-') === 0) {
                $classes[] = 'mc4wp-form-theme';
            }

            $classes[] = 'mc4wp-form-' . $form->settings['css'];
        }

        // add classes from config array
        if (! empty($this->config['element_class'])) {
            $classes = array_merge($classes, explode(' ', $this->config['element_class']));
        }

        /**
         * Filters `class` attributes for the `<form>` element.
         *
         * @param array $classes
         * @param MC4WP_Form $form
         */
        $classes = apply_filters('mc4wp_form_css_classes', $classes, $form);

        return implode(' ', $classes);
    }
}
