have no such limit, so the dialog asks for more
	 * and the note below describes the real constraint rather than a mail client
	 * that is not in this flow.
	 *
	 * @param int $max_chars Characters of log to include.
	 * @since 2.12.7
	 * @return string
	 */
	private function get_support_log_block( $max_chars = 1200 ) {
		$log   = Client_Logger::get_tail( $max_chars );
		$block = '---' . "\n";

		if ( '' === $log['text'] ) {
			return $block . __( 'Debug log: no entries recorded.', 'sureforms' );
		}

		$block .= sprintf(
			/* translators: 1: entries shown, 2: entries recorded. */
			__( 'Debug log (most recent %1$d of %2$d entries)', 'sureforms' ),
			$log['shown'],
			$log['total']
		) . "\n";

		// Fenced so it survives a reply and reads as data rather than prose wherever
		// Markdown is rendered.
		$block .= '```' . "\n" . $log['text'] . "\n" . '```';

		if ( $log['shown'] < $log['total'] ) {
			$block .= "\n\n" . __( 'Older entries were left out to keep this excerpt readable. The full log can be downloaded from SureForms → Settings → General.', 'sureforms' );
		}

		return $block;
	}

	/**
	 * Subject and countless opening line for one kind of failure.
	 *
	 * Both come from here so they cannot drift apart: a subject naming one problem
	 * over a body describing another is worse than either alone. The counted form
	 * of the opening line lives in get_support_count_sentence(), which needs
	 * `_n()`'s literals and so cannot be an array lookup.
	 *
	 * An unknown or absent category gets deliberately neutral wording. The
	 * alternative -- defaulting to the submission copy -- states something specific
	 * that may not be true, and an item contributed through srfm_action_items has no
	 * category at all.
	 *
	 * @param string $category One of Client_Logger::CATEGORIES.
	 * @since 2.12.7
	 * @return array{subject:string,anon:string}
	 */
	private function get_support_copy( $category ) {
		$copy = [
			'submission'   => [
				/* translators: %s: site host. */
				'subject' => __( 'SureForms: form submissions are failing on %s', 'sureforms' ),
				/* translators: %s: site host. */
				'anon'    => __( 'SureForms has recorded form submissions on %s that could not be completed.', 'sureforms' ),
			],
			'notification' => [
				/* translators: %s: site host. */
				'subject' => __( 'SureForms: notification emails are not being sent on %s', 'sureforms' ),
				/* translators: %s: site host. */
				'anon'    => __( 'SureForms saved entries on %s but could not send the notification emails for them.', 'sureforms' ),
			],
			'integration'  => [
				/* translators: %s: site host. */
				'subject' => __( 'SureForms: an integration is not receiving entries on %s', 'sureforms' ),
				/* translators: %s: site host. */
				'anon'    => __( 'SureForms saved entries on %s but could not pass them to a connected service.', 'sureforms' ),
			],
		];

		if ( isset( $copy[ $category ] ) ) {
			return $copy[ $category ];
		}

		return [
			/* translators: %s: site host. */
			'subject' => __( 'SureForms: a problem with the forms on %s', 'sureforms' ),
			/* translators: %s: site host. */
			'anon'    => __( 'SureForms has recorded a problem with the forms on %s.', 'sureforms' ),
		];
	}

	/**
	 * The sentence that opens the support email, with the failure count in it.
	 *
	 * A switch with literal `_n()` calls rather than a singular/plural pair looked
	 * up from an array. `_n()` has to see its two literals at extraction time to
	 * emit an `msgid_plural`, and only that lets a locale supply the number of
	 * forms it actually uses -- Polish and Russian need three, Arabic six,
	 * Japanese one. Choosing on `1 === $count` in PHP is correct for English and
	 * wrong everywhere with a different plural rule.
	 *
	 * @param string $category One of Client_Logger::CATEGORIES. Unknown or absent
	 *                         gets neutral wording rather than a specific claim.
	 * @param int    $count    Failures recorded for that category.
	 * @since 2.12.7
	 * @return string
	 */
	private function get_support_count_sentence( $category, $count ) {
		switch ( $category ) {
			case 'submission':
				return sprintf(
					/* translators: %d: number of failed submissions. */
					_n(
						'SureForms has recorded %d form submission that could not be completed.',
						'SureForms has recorded %d form submissions that could not be completed.',
						$count,
						'sureforms'
					),
					$count
				);

			case 'notification':
				return sprintf(
					/* translators: %d: number of failed notifications. */
					_n(
						'SureForms saved %d entry but could not send the notification email for it.',
						'SureForms saved %d entries but could not send the notification emails for them.',
						$count,
						'sureforms'
					),
					$count
				);

			case 'integration':
				return sprintf(
					/* translators: %d: number of failed integration hand-offs. */
					_n(
						'SureForms saved %d entry but could not pass it to a connected service.',
						'SureForms saved %d entries but could not pass them to a connected service.',
						$count,
						'sureforms'
					),
					$count
				);

			default:
				return sprintf(
					/* translators: %d: number of recorded problems. */
					_n(
						'SureForms has recorded %d problem with the forms on this site.',
						'SureForms has recorded %d problems with the forms on this site.',
						$count,
						'sureforms'
					),
					$count
				);
		}
	}

	/**
	 * Diagnostics block for the support report.
	 *
	 * Carries what support would otherwise have to ask for, so the first reply can
	 * be an answer rather than a questionnaire.
	 *
	 * The count is the one for this category, not get_fault_streak(), which reports
	 * submissions only -- so a notification failure used to quote a number from an
	 * unrelated counter, often zero.
	 *
	 * @param string $category   One of Client_Logger::CATEGORIES.
	 * @param string $form_title Form the failure was recorded against, when known.
	 * @since 2.12.6
	 * @return string
	 */
	private function get_support_message( $category = '', $form_title = '' ) {
		global $wp_version;

		$failures = Client_Logger::get_failures();
		$count    = Helper::get_integer_value( $failures[ $category ]['count'] ?? 0 );
		$copy     = $this->get_support_copy( $category );

		// With nothing recorded, describe the failure without a number. The old
		// max( 1, $count ) reported "recorded 1 problem" and "Recorded failures: 1"
		// for a count nobody recorded -- a number support would then chase.
		$host = Helper::get_string_value( wp_parse_url( home_url(), PHP_URL_HOST ) );

		$lines = [
			__( 'Hello SureForms support,', 'sureforms' ),
			'',
			$count > 0
				? $this->get_support_count_sentence( $category, $count )
				: sprintf( $copy['anon'], $host ),
		];

		if ( '' !== $form_title ) {
			$lines[] = '';
			$lines[] = sprintf(
				/* translators: %s: form title. */
				__( 'Form: %s', 'sureforms' ),
				$form_title
			);
		}

		// Once: each call reads an option and a site option.
		$caching = Helper::get_active_caching_plugin();

		$lines = array_merge(
			$lines,
			[
				'',
				'---',
				__( 'Site details', 'sureforms' ),
				// Labels translated, values not. The site owner reads this on screen
				// before sending it, so the labels are copy; the values are machine
				// data -- a version, a URL, a plugin name -- and stay verbatim. The
				// debug log below is left alone entirely for the same reason.
				/* translators: %s: site address. */
				sprintf( __( 'Site: %s', 'sureforms' ), home_url() ),
				/* translators: %s: SureForms version. */
				sprintf( __( 'SureForms: %s', 'sureforms' ), SRFM_VER ),
				sprintf(
					/* translators: %s: SureForms Pro version, or a note that it is not active. */
					__( 'SureForms Pro: %s', 'sureforms' ),
					Helper::has_pro() && defined( 'SRFM_PRO_VER' ) ? SRFM_PRO_VER : __( 'not active', 'sureforms' )
				),
				/* translators: %s: WordPress version. */
				sprintf( __( 'WordPress: %s', 'sureforms' ), Helper::get_string_value( $wp_version ) ),
				/* translators: %s: PHP version. */
				sprintf( __( 'PHP: %s', 'sureforms' ), PHP_VERSION ),
				sprintf(
					/* translators: %s: caching plugin name, or a note that none was detected. */
					__( 'Caching: %s', 'sureforms' ),
					'' !== $caching ? $caching : __( 'none detected', 'sureforms' )
				),
				sprintf(
					/* translators: %s: number of recorded failures, or a note that none were. */
					__( 'Recorded failures: %s', 'sureforms' ),
					$count > 0 ? Helper::get_string_value( $count ) : __( 'none recorded', 'sureforms' )
				),
			]
		);

		// Only when there is one. A repeat report is worth knowing about: the same
		// category having been reported before means the last answer did not hold,
		// which is a different conversation from a first report. Appended with the
		// rest of the site details rather than raised to the top, because it is
		// context for them rather than a headline.
		//
		// Survives only until the next success in that category, because
		// clear_category() unsets the whole record -- so in practice it is
		// reachable for 'integration', which has no success signal, and transient
		// for the other two.
		//
		// Stored as time(), a UTC epoch comparable with the sibling 'at', and
		// formatted here with wp_date() so it reads in the site's timezone rather
		// than the server's.
		$acked_at = Helper::get_integer_value( $failures[ $category ]['acked_at'] ?? 0 );

		if ( $acked_at > 0 ) {
			$lines[] = sprintf(
				/* translators: %s: date and time of the previous report, in the site's timezone. */
				__( 'Previously reported: %s', 'sureforms' ),
				Helper::get_string_value( wp_date( 'Y-m-d H:i T', $acked_at ) )
			);
		}

		return implode( "\n", $lines );
	}

	/**
	 * Record one dismissal, shared by the AJAX and no-JS entry points.
	 *
	 * Allowlisted, so only advisory items can be dismissed. A run of failed
	 * submissions is a fault and must stay put until it actually resolves --
	 * otherwise a crafted request could silence the one message that matters.
	 *
	 * @param string $item_id Item to dismiss.
	 * @since 2.12.6
	 * @return bool False when the id is not dismissible.
	 */
	private function dismiss_action_item( $item_id ) {
		if ( ! in_array( $item_id, [ 'caching_plugin' ], true ) ) {
			return false;
		}

		$dismissed = Helper::get_array_value( Helper::get_srfm_option( 'dismissed_action_items', [] ) );

		if ( ! in_array( $item_id, $dismissed, true ) ) {
			$dismissed[] = $item_id;
			Helper::update_srfm_option( 'dismissed_action_items', $dismissed );

			// Recorded here rather than at each caller: both the cross in the
			// dashboard panel and the no-JS link in the classic notice land here.
			$this->track_notice_event( $item_id . '_notice_dismiss' );
		}

		return true;
	}
}