<?php
/**
 * Human-readable automation step summaries for the admin run history.
 *
 * @package Bookline
 */

declare( strict_types=1 );

namespace Bookline\Application\Automation;

use Bookline\Domain\Automation\ActionResult;
use Bookline\Domain\Automation\ActionStep;
use Bookline\Domain\Automation\AutomationAction;
use Bookline\Domain\Automation\AutomationRecipient;
use Bookline\Domain\Automation\SendIntent;

/**
 * Formats operator-facing step rows (British English).
 *
 * @since 0.1.0
 */
final class AutomationStepSummary {

	/**
	 * Known notification template labels.
	 *
	 * @var array<string, string>
	 */
	private const TEMPLATE_LABELS = [
		'booking.confirmed.customer'        => 'Booking confirmation',
		'booking.reminder.customer'         => 'Appointment reminder',
		'booking.reminder.agent'            => 'Staff appointment reminder',
		'booking.reminder_soon.customer'    => 'On-the-way reminder',
		'booking.followup.customer'         => 'Thank-you message',
		'booking.rebook.customer'           => 'Invitation to rebook',
		'booking.noshow.customer'           => 'No-show follow-up',
		'booking.prep.customer'             => 'What to expect before visit',
		'booking.cancelled_rebook.customer' => 'Rebook after cancellation',
		'payment.balance_due.customer'      => 'Balance due reminder',
		'payment.failed.customer'           => 'Payment failed notice',
		'customer.welcome'                  => 'Welcome message',
		'intent.resume.customer'            => 'Resume booking reminder',
		'intent.resume_again.customer'      => 'Second resume booking reminder',
	];

	/**
	 * Metadata merged into a persisted step row.
	 *
	 * @param ActionStep            $step   Step.
	 * @param ActionResult          $result Result.
	 * @param AutomationAction|null $action Registry action.
	 * @return array<string, mixed>
	 */
	public static function meta( ActionStep $step, ActionResult $result, ?AutomationAction $action ): array {
		return [
			'action_type'  => $step->type(),
			'action_label' => null !== $action ? $action->label() : self::type_label( $step->type() ),
			'summary'      => self::summary( $step, $result ),
			'status_label' => self::status_label( $result->status() ),
		];
	}

	/**
	 * Operator-facing status label.
	 *
	 * @param string $status Step status.
	 * @return string
	 */
	public static function status_label( string $status ): string {
		return match ( $status ) {
			'drafted'   => 'Drafted — not sent',
			'completed' => 'Done',
			'skipped'   => 'Skipped',
			'failed'    => 'Failed',
			default     => ucfirst( $status ),
		};
	}

	/**
	 * Plain-language step summary.
	 *
	 * @param ActionStep   $step   Step.
	 * @param ActionResult $result Result.
	 * @return string
	 */
	public static function summary( ActionStep $step, ActionResult $result ): string {
		$rendered = $result->rendered();
		if ( is_string( $rendered ) && str_starts_with( $rendered, 'Wait skipped by operator.' ) ) {
			return 'Wait skipped by operator';
		}

		return match ( $step->type() ) {
			'send_notification_template', 'send_email' => self::send_summary( $step ),
			'add_customer_tag' => self::tag_summary( $step ),
			'add_internal_note' => self::note_summary( $step ),
			'change_booking_status' => self::status_change_summary( $step ),
			'wait' => self::wait_summary( $step ),
			'log_activity' => self::activity_summary( $step ),
			'if' => self::if_summary( $rendered ),
			'http_integration' => self::http_summary( $rendered ),
			default => self::fallback_summary( $step, $rendered ),
		};
	}

	/**
	 * Metadata for a synthetic step row (e.g. skip-wait).
	 *
	 * @param string $type    Action type.
	 * @param string $summary Summary text.
	 * @param string $status  Step status.
	 * @return array<string, mixed>
	 */
	public static function meta_for_type( string $type, string $summary, string $status ): array {
		return [
			'action_type'  => $type,
			'action_label' => self::type_label( $type ),
			'summary'      => $summary,
			'status_label' => self::status_label( $status ),
		];
	}

	/**
	 * Send-notification step summary.
	 *
	 * @param ActionStep $step Step.
	 * @return string
	 */
	private static function send_summary( ActionStep $step ): string {
		$config   = $step->config();
		$key      = isset( $config['template_key'] ) ? (string) $config['template_key'] : '';
		$template = self::template_label( $key );
		$recipient = self::recipient_label( $step->recipient() ?? AutomationRecipient::Customer );
		$intent    = SendIntent::Marketing === ( $step->intent() ?? SendIntent::Transactional )
			? 'marketing'
			: 'transactional';

		return sprintf( 'Send “%s” to %s (%s)', $template, $recipient, $intent );
	}

	/**
	 * Customer tag step summary.
	 *
	 * @param ActionStep $step Step.
	 * @return string
	 */
	private static function tag_summary( ActionStep $step ): string {
		$tag = isset( $step->config()['tag'] ) ? trim( (string) $step->config()['tag'] ) : '';
		if ( '' === $tag ) {
			return 'Add a customer tag';
		}
		return sprintf( 'Tag customer as “%s”', $tag );
	}

	/**
	 * Internal note step summary.
	 *
	 * @param ActionStep $step Step.
	 * @return string
	 */
	private static function note_summary( ActionStep $step ): string {
		$note = isset( $step->config()['note'] ) ? trim( (string) $step->config()['note'] ) : '';
		if ( '' === $note ) {
			return 'Add an internal note';
		}
		return $note;
	}

	/**
	 * Booking status change step summary.
	 *
	 * @param ActionStep $step Step.
	 * @return string
	 */
	private static function status_change_summary( ActionStep $step ): string {
		$status = isset( $step->config()['status'] ) ? (string) $step->config()['status'] : '';
		$label  = self::humanise_token( $status );
		return '' === $label ? 'Change booking status' : sprintf( 'Change booking status to %s', $label );
	}

	/**
	 * Wait step summary.
	 *
	 * @param ActionStep $step Step.
	 * @return string
	 */
	private static function wait_summary( ActionStep $step ): string {
		$minutes = $step->delay_minutes();
		if ( $minutes > 0 ) {
			return sprintf( 'Wait %d minute%s before continuing', $minutes, 1 === $minutes ? '' : 's' );
		}
		return 'Pause before the next step';
	}

	/**
	 * Activity log step summary.
	 *
	 * @param ActionStep $step Step.
	 * @return string
	 */
	private static function activity_summary( ActionStep $step ): string {
		$config = $step->config();
		foreach ( [ 'message', 'note', 'n' ] as $key ) {
			if ( isset( $config[ $key ] ) && is_scalar( $config[ $key ] ) && '' !== trim( (string) $config[ $key ] ) ) {
				return sprintf( 'Log activity: %s', trim( (string) $config[ $key ] ) );
			}
		}
		return 'Log activity';
	}

	/**
	 * Condition branch step summary.
	 *
	 * @param string|null $rendered Raw result text.
	 * @return string
	 */
	private static function if_summary( ?string $rendered ): string {
		if ( 'if:pass' === $rendered ) {
			return 'Condition passed — continue on “yes” branch';
		}
		if ( 'if:fail' === $rendered ) {
			return 'Condition failed — continue on “no” branch';
		}
		return 'Check condition';
	}

	/**
	 * Webhook step summary.
	 *
	 * @param string|null $rendered Raw result text.
	 * @return string
	 */
	private static function http_summary( ?string $rendered ): string {
		if ( ! is_string( $rendered ) || '' === $rendered ) {
			return 'Call webhook';
		}
		$line = strtok( $rendered, "\n" );
		return is_string( $line ) && '' !== $line ? 'Call webhook: ' . $line : 'Call webhook';
	}

	/**
	 * Fallback when no specialised formatter applies.
	 *
	 * @param ActionStep  $step     Step.
	 * @param string|null $rendered Raw result text.
	 * @return string
	 */
	private static function fallback_summary( ActionStep $step, ?string $rendered ): string {
		if ( is_string( $rendered ) && '' !== $rendered && ! str_contains( $rendered, '{' ) ) {
			return $rendered;
		}
		return self::type_label( $step->type() );
	}

	/**
	 * Resolve a template key to a label.
	 *
	 * @param string $key Template key.
	 * @return string
	 */
	private static function template_label( string $key ): string {
		if ( isset( self::TEMPLATE_LABELS[ $key ] ) ) {
			return self::TEMPLATE_LABELS[ $key ];
		}
		if ( '' === $key ) {
			return 'Notification';
		}
		$trimmed = preg_replace( '/^(booking|customer|payment|intent)\./', '', $key );
		$trimmed = is_string( $trimmed ) ? preg_replace( '/\.(customer|agent)$/', '', $trimmed ) : $key;
		$trimmed = is_string( $trimmed ) ? $trimmed : $key;
		return self::humanise_token( $trimmed );
	}

	/**
	 * Recipient label for summaries.
	 *
	 * @param AutomationRecipient $recipient Recipient.
	 * @return string
	 */
	private static function recipient_label( AutomationRecipient $recipient ): string {
		return match ( $recipient ) {
			AutomationRecipient::Customer => 'customer',
			AutomationRecipient::Agent    => 'staff member',
			AutomationRecipient::Admin    => 'administrator',
		};
	}

	/**
	 * Action type label.
	 *
	 * @param string $type Action type.
	 * @return string
	 */
	private static function type_label( string $type ): string {
		return match ( $type ) {
			'send_notification_template' => 'Send notification',
			'send_email'                 => 'Send email',
			'add_customer_tag'           => 'Add customer tag',
			'add_internal_note'          => 'Add internal note',
			'change_booking_status'      => 'Change booking status',
			'wait'                       => 'Wait',
			'log_activity'               => 'Log activity',
			'http_integration'           => 'Webhook',
			'if'                         => 'Condition',
			'goto'                       => 'Go to step',
			default                      => self::humanise_token( $type ),
		};
	}

	/**
	 * Turn a machine token into title case words.
	 *
	 * @param string $token Token.
	 * @return string
	 */
	private static function humanise_token( string $token ): string {
		$token = str_replace( [ '_', '.', '-' ], ' ', $token );
		$token = preg_replace( '/\s+/', ' ', $token );
		$token = is_string( $token ) ? trim( $token ) : '';
		if ( '' === $token ) {
			return '';
		}
		return ucfirst( $token );
	}
}