<?php
// phpcs:disable PluginCheck.Security.DirectDB.UnescapedDBParameter,WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching,WordPress.DB.DirectDatabaseQuery.NoCaching -- Custom plugin tables require direct queries,WordPress.DB.PreparedSQL.InterpolatedNotPrepared,WordPress.DB.PreparedSQL.NotPrepared -- Custom plugin tables; all table names are internal constants never from user input
if ( ! defined( 'ABSPATH' ) ) exit;

/**
 * ACQUIS_Email_Engine
 *
 * Orchestrates the full email-delivery pipeline:
 *  - Checks delivery mode setting
 *  - Renders branded HTML email via ACQUIS_Email_Template
 *  - Sends via wp_mail (compatible with any SMTP plugin)
 *  - Logs every attempt to acquis_email_logs
 *  - Fires acquis_after_email_sent action for extensibility
 */
class ACQUIS_Email_Engine {

    /**
     * Main entry point call after lead is saved and token is created.
     *
     * @param  int    $lead_id       DB id of the new lead row
     * @param  string $full_name
     * @param  string $email
     * @param  string $download_url  Signed, expiring URL
     * @param  array  $file          File data array from ACQUIS_File_Manager
     * @param  int    $form_id       Optional. The custom form (if any) this lead came
     *                                through. When that form has its own email template
     *                                enabled, it's used instead of the global default.
     * @param  array  $custom_fields Optional. field_key => submitted value, for any
     *                                custom form fields beyond name/email lets a
     *                                form's own email template reference {field_key}
     *                                tags (e.g. {phone}, {company}).
     * @return bool                  true on success, false on failure / skipped
     */
    public static function send( $lead_id, $full_name, $email, $download_url, $file, $form_id = 0, $custom_fields = array() ) {
        $delivery_mode = get_option( 'acquis_delivery_mode', 'both' );

        // 'instant' mode = never send email
        if ( 'instant' === $delivery_mode ) {
            ACQUIS_Database::log_integration( $lead_id, 'email', 'skipped', 'Delivery mode is instant-only.' );
            return false;
        }

        $form_email_settings = self::get_form_email_settings( $form_id );

        // No file attached (standalone form) — use the standalone-forms
        // template tier instead of the file-download one, unless this
        // form has its own override enabled (checked first, above).
        $is_standalone = empty( $file['id'] );

        // Reserve a log row first so we have a log_id to attach tracking
        // (pixel + click-wrapper) to before the template is even rendered.
        $log_id = ACQUIS_Database::log_email( $lead_id, $email, '', 'queued', 'wp_mail' );

        $tracked_download_url = $download_url;
        if ( $log_id && class_exists( 'ACQUIS_Email_Tracking' ) ) {
            $tracked_download_url = ACQUIS_Email_Tracking::wrap_link( $log_id, $download_url );
        }

        // Build context for template
        $context = array(
            'full_name'     => $full_name,
            'email'         => $email,
            'file_name'     => $file['title'],
            'download_link' => $tracked_download_url,
            'site_name'     => get_bloginfo( 'name' ),
            'custom_fields' => is_array( $custom_fields ) ? $custom_fields : array(),
        );

        $subject      = ACQUIS_Email_Template::render_subject( $context, $form_email_settings, $is_standalone );
        $html_body    = ACQUIS_Email_Template::render( $context, $form_email_settings, $is_standalone );
        $plain_body   = ACQUIS_Email_Template::render_plain_text( $context, $is_standalone );
        $from_name    = sanitize_text_field( get_option( 'acquis_email_from_name', get_bloginfo( 'name' ) ) );
        $from_address = sanitize_email( get_option( 'acquis_email_from_address', get_bloginfo( 'admin_email' ) ) );

        // Append the open-tracking pixel, and now that we know the real
        // subject, store it on the log row reserved above.
        if ( $log_id ) {
            global $wpdb;
            $wpdb->update( $wpdb->prefix . 'acquis_email_logs', array( 'subject' => $subject ), array( 'id' => $log_id ) );
            if ( class_exists( 'ACQUIS_Email_Tracking' ) ) {
                $html_body .= ACQUIS_Email_Tracking::pixel_tag( $log_id );
            }
        }

        // Build wp_mail headers
        $headers = array(
            'Content-Type: text/html; charset=UTF-8',
            "From: {$from_name} <{$from_address}>",
            "Reply-To: {$from_address}",
        );

        // Allow other plugins / SMTP connectors to inject headers
        // phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedHooknameFound
        $headers = apply_filters( 'acquis_email_headers', $headers, $lead_id, $context );

        // Attach plain text alternative many SMTP plugins handle multipart automatically,
        // but we also filter body for those that don't
        add_filter( 'wp_mail_content_type', array( __CLASS__, 'set_html_content_type' ) );
        $sent = wp_mail( $email, $subject, $html_body, $headers );
        remove_filter( 'wp_mail_content_type', array( __CLASS__, 'set_html_content_type' ) );

        // Update log
        if ( $log_id ) {
            ACQUIS_Database::update_email_log_status(
                $log_id,
                $sent ? 'sent' : 'failed',
                $sent ? '' : 'wp_mail() returned false check your SMTP configuration.'
            );
        }

        // Fire action so other plugins / Pro add-ons can hook in
        // phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedHooknameFound
        do_action( 'acquis_after_email_sent', $lead_id, $email, $sent, $context );

        return $sent;
    }

    /**
     * True when the given form is a standalone form (purpose != file_gate),
     * used to preview the correct template tier in send_test().
     *
     * @param  int $form_id
     * @return bool
     */
    private static function is_standalone_form( $form_id ) {
        $form_id = absint( $form_id );
        if ( ! $form_id || ! class_exists( 'ACQUIS_P3_DB' ) ) {
            return false;
        }
        $form = ACQUIS_P3_DB::get_form( $form_id );
        if ( ! $form || ! is_array( $form->settings ) ) {
            return false;
        }
        return 'file_gate' !== ( $form->settings['purpose'] ?? 'file_gate' );
    }

    /**
     * Look up a form's `settings['email']` override block.
     *
     * @param  int $form_id
     * @return array Empty array when there's no form, no ACQUIS_P3_DB, or no override.
     */
    private static function get_form_email_settings( $form_id ) {
        $form_id = absint( $form_id );
        if ( ! $form_id || ! class_exists( 'ACQUIS_P3_DB' ) ) {
            return array();
        }
        $form = ACQUIS_P3_DB::get_form( $form_id );
        if ( ! $form || empty( $form->settings ) || ! is_array( $form->settings ) ) {
            return array();
        }
        return isset( $form->settings['email'] ) && is_array( $form->settings['email'] )
            ? $form->settings['email']
            : array();
    }

    /**
     * Plausible sample values for a form's custom fields, keyed by
     * field_key, so a test send shows {field_key} tags replaced with
     * believable example data rather than the literal unreplaced tag.
     * Falls back to a generic placeholder for field types it doesn't
     * have a specific sample for.
     *
     * @param  int $form_id
     * @return array field_key => sample value
     */
    private static function sample_custom_fields( $form_id ) {
        $form_id = absint( $form_id );
        if ( ! $form_id || ! class_exists( 'ACQUIS_P3_DB' ) ) {
            return array();
        }
        $form = ACQUIS_P3_DB::get_form( $form_id );
        if ( ! $form || empty( $form->fields ) ) {
            return array();
        }

        $samples_by_type = array(
            'email'    => 'amara@example.com',
            'phone'    => '+1 (555) 123-4567',
            'number'   => '42',
            'date'     => gmdate( 'Y-m-d' ),
            'country'  => 'Nigeria',
            'dropdown' => 'Option A',
            'radio'    => 'Option A',
            'checkbox' => 'Option A, Option B',
        );

        $sample = array();
        foreach ( $form->fields as $field ) {
            $key = $field->field_key ?? '';
            if ( '' === $key || in_array( $key, array( 'full_name', 'email', 'first_name', 'last_name' ), true ) ) {
                continue; // already covered by the fixed {full_name}/{email} tags
            }
            $type = $field->field_type ?? 'text';
            $sample[ $key ] = $samples_by_type[ $type ] ?? ( 'Sample ' . ( $field->label ?: $key ) );
        }

        return $sample;
    }

    /**
     * Content-type filter callback hooked only during send().
     */
    public static function set_html_content_type() {
        return 'text/html';
    }

    /**
     * Test-send: sends a sample email to the admin for template preview.
     *
     * @param  string $to       Recipient address
     * @param  int    $form_id  Optional. Preview a specific form's email override instead
     *                           of the global default.
     * @return bool
     */
    public static function send_test( $to, $form_id = 0 ) {
        $is_standalone = self::is_standalone_form( $form_id );

        $context = array(
            'full_name'     => 'Test User',
            'email'         => $to,
            'file_name'     => $is_standalone ? '' : 'Sample Document.pdf',
            'download_link' => $is_standalone ? '' : home_url( '/?acquis_test=1' ),
            'site_name'     => get_bloginfo( 'name' ),
            'custom_fields' => self::sample_custom_fields( $form_id ),
        );

        $form_email_settings = self::get_form_email_settings( $form_id );

        $subject   = '[TEST] ' . ACQUIS_Email_Template::render_subject( $context, $form_email_settings, $is_standalone );
        $html_body = ACQUIS_Email_Template::render( $context, $form_email_settings, $is_standalone );

        $from_name    = sanitize_text_field( get_option( 'acquis_email_from_name', get_bloginfo( 'name' ) ) );
        $from_address = sanitize_email( get_option( 'acquis_email_from_address', get_bloginfo( 'admin_email' ) ) );
        $headers      = array(
            'Content-Type: text/html; charset=UTF-8',
            "From: {$from_name} <{$from_address}>",
        );

        add_filter( 'wp_mail_content_type', array( __CLASS__, 'set_html_content_type' ) );
        $sent = wp_mail( $to, $subject, $html_body, $headers );
        remove_filter( 'wp_mail_content_type', array( __CLASS__, 'set_html_content_type' ) );

        return $sent;
    }
}