<?php

namespace ABeCe\Booking\Service;

use ABeCe\Booking\Repository\OpeningHoursRepository;
use ABeCe\Booking\Repository\ScheduleExceptionsRepository;
use ABeCe\Booking\Support\Time;

final class OperatingScheduleService {
	public function __construct( private readonly OpeningHoursRepository $hours, private readonly ScheduleExceptionsRepository $exceptions, private readonly SunService $sun ) {}

	/** Returns merged half-open timestamp intervals before booking-grid alignment. */
	public function intervals( int $resource_id, string $date ): array {
		return $this->intervalsFromRows($resource_id, $date, $this->hours->forDay($resource_id, (int) Time::day($date)?->format('N')), $this->exceptions->forDate($resource_id, $date));
	}

	/** The same scheduling rules for batched reports; no per-resource/day SQL. */
	public function intervalsFromRows(int $resource_id, string $date, array $hours, array $exceptions): array {
		$day = Time::day( $date );
		if ( ! $day ) { return []; }
		$next_day = Time::nextDay( $date );
		if ( ! $next_day ) { return []; }
		$rows = $this->scope( $exceptions, $resource_id );
		$is_exception = (bool) $rows;
		if ( ! $rows ) { $rows = $this->scope( $hours, $resource_id ); }
		foreach ( $rows as $row ) { if ( $row['is_closed'] ) { return []; } }
		$intervals = [];
		foreach ( $rows as $row ) {
			if ( ! $is_exception && 'sun' === $row['opening_mode'] ) {
				$events = $this->sun->events( $date );
				if ( ! $events ) { continue; }
				$start = $events['sunrise'] + ( $row['sunrise_offset_minutes'] ?? 0 ) * 60;
				$end = $events['sunset'] + ( $row['sunset_offset_minutes'] ?? 0 ) * 60;
				foreach ( [ 'min_open_time', 'max_close_time' ] as $field ) {
					if ( null === $row[ $field ] ) { continue; }
					$limit = Time::local( $date, $row[ $field ] );
					if ( ! $limit ) { $end = $start; break; }
					if ( 'min_open_time' === $field ) { $start = max( $start, $limit->getTimestamp() ); }
					else { $end = min( $end, $limit->getTimestamp() ); }
				}
			} else {
				$open = '00:00:00' === ( $row['opens_at'] ?? null ) ? $day : Time::local( $date, $row['opens_at'] ?? '' );
				$close = Time::local( $date, $row['closes_at'] ?? '' );
				if ( ! $open || ! $close ) { continue; }
				$start = $open->getTimestamp(); $end = $close->getTimestamp();
			}
			$start = max( $start, $day->getTimestamp() );
			$end = min( $end, $next_day->getTimestamp() );
			if ( $start < $end ) { $intervals[] = [ $start, $end ]; }
		}
		usort( $intervals, static fn( $a, $b ) => $a[0] <=> $b[0] );
		$merged = [];
		foreach ( $intervals as $interval ) {
			$last = count( $merged ) - 1;
			if ( $last >= 0 && $interval[0] <= $merged[ $last ][1] ) { $merged[ $last ][1] = max( $merged[ $last ][1], $interval[1] ); }
			else { $merged[] = $interval; }
		}
		return $merged;
	}

	public function publicTitle(int $resource_id,string $date):?string {
        $rows=$this->scope($this->exceptions->forDate($resource_id,$date),$resource_id);$titles=array_values(array_unique(array_filter(array_column($rows,'public_title'))));return $titles?implode(' · ',$titles):null;
    }

	private function scope( array $rows, int $resource_id ): array {
		$specific = array_values( array_filter( $rows, static fn( $row ) => $row['resource_id'] === $resource_id ) );
		return $specific ?: array_values( array_filter( $rows, static fn( $row ) => null === $row['resource_id'] ) );
	}
}