<?php
namespace DayTidy\Booking;

use DayTidy\Config as DayTidyConfig;
use DayTidy\DateTime;
use DayTidy\Entities\Offering;
use DayTidy\Input;
use DayTidy\Posts\Offering as OfferingPost;
use DayTidy\SingleOffering\PageResolver;
use DayTidy\Slug;
use DateTimeImmutable;
use DateTimeZone;
use Exception;
use stdClass;
use Webilia\WP\Formats\Date as DateFormat;
use Webilia\WP\Formats\DateTime as DateTimeFormat;
use Webilia\WP\Formats\Time as TimeFormat;
use Webilia\WP\Helpers\Arr;

/**
 * Booking Request
 */
class Request
{
    /**
     * Get Booking Request
     *
     * @return stdClass|null
     */
    public static function get(): ?stdClass
    {
        // Request Object
        $request = new stdClass();
        $prefill = self::prefill();

        $daytidy = isset($_REQUEST['daytidy']) && is_array($_REQUEST['daytidy'])
            ? wp_unslash($_REQUEST['daytidy'])
            : [];
        if (Arr::notset($daytidy, 'json') && !count($prefill)) return null;

        $json = isset($daytidy['json']) && is_string($daytidy['json']) ? $daytidy['json'] : '{}';
        unset($daytidy['json']);

        $data = json_decode($json, true);

        // Not Valid Array
        if (Arr::not($data)) $data = [];

        $data = self::submittedValues($data);
        $daytidy = self::submittedValues($daytidy);

        // New Request
        $all = $daytidy + $data + $prefill + [
            'step' => '',
            'sessions' => [],
            'option_sessions' => [],
        ];

        // Populate Object
        foreach ($all as $key => $value) $request->{$key} = $value;

        // Return Object
        return $request;
    }

    /**
     * @param array<string, mixed> $data
     * @return array<string, mixed>
     */
    private static function submittedValues(array $data): array
    {
        $values = [];
        foreach (['id', 'step', 'offering', 'date', 'time', 'method', 'coupon', 'skippable', 'gateway', 'prev'] as $key)
        {
            if (!isset($data[$key]) || !is_scalar($data[$key])) continue;

            $values[$key] = sanitize_text_field((string) $data[$key]);
        }

        // Clean nested submitted/decoded values before they reach the Draft.
        // The Draft setters and CustomFields then apply field-specific rules.
        foreach (['sessions', 'option_sessions', 'options', 'resources', 'form', 'participants', 'registration'] as $key)
        {
            if (isset($data[$key]) && is_array($data[$key])) $values[$key] = Input::sanitize($data[$key]);
        }

        return $values;
    }

    /**
     * @return mixed[]
     */
    private static function prefill(): array
    {
        $offering_id = self::offeringId();

        if ($offering_id <= 0) return [];

        $prefill = [
            'offering' => $offering_id,
        ];

        $session = self::sessionQueryString();
        if ($session !== '') $prefill['sessions'] = [$session];

        $date = self::queryString(PageResolver::QUERY_DATE);
        if ($date !== '') $prefill['date'] = $date;

        $time = self::queryString(PageResolver::QUERY_TIME);
        if ($time !== '') $prefill['time'] = $time;

        if ($session !== '' && ($date === '' || $time === ''))
        {
            $parts = self::sessionLocalParts($offering_id, $session);

            if ($date === '' && isset($parts['date'])) $prefill['date'] = $parts['date'];
            if ($time === '' && isset($parts['time'])) $prefill['time'] = $parts['time'];
        }

        return $prefill;
    }

    private static function offeringId(): int
    {
        if (isset($_GET[PageResolver::QUERY_OFFERING]) && is_scalar($_GET[PageResolver::QUERY_OFFERING]))
        {
            return absint(wp_unslash((string) $_GET[PageResolver::QUERY_OFFERING]));
        }

        $queried_id = (int) get_queried_object_id();
        if ($queried_id > 0 && get_post_type($queried_id) === OfferingPost::PT) return $queried_id;

        return 0;
    }

    private static function queryString(string $key): string
    {
        if (!isset($_GET[$key]) || !is_scalar($_GET[$key])) return '';

        return sanitize_text_field(wp_unslash((string) $_GET[$key]));
    }

    private static function sessionQueryString(): string
    {
        $session = self::queryString(PageResolver::QUERY_SESSION);
        if ($session === '')
        {
            $requested = get_query_var(Slug::sessions());
            $session = is_scalar($requested) ? sanitize_text_field((string) $requested) : '';
        }

        if ($session === '') return '';

        return self::normalizeSession($session);
    }

    private static function normalizeSession(string $session): string
    {
        if (preg_match('/^\d{14}$/', $session))
        {
            $datetime = DateTimeImmutable::createFromFormat('!YmdHis', $session, new DateTimeZone('UTC'));
            if ($datetime instanceof DateTimeImmutable) return $datetime->format(DateTimeFormat::tech());
        }

        if (preg_match('/^\d{8}T\d{6}$/', $session))
        {
            $datetime = DateTimeImmutable::createFromFormat('!Ymd\THis', $session, new DateTimeZone('UTC'));
            if ($datetime instanceof DateTimeImmutable) return $datetime->format(DateTimeFormat::tech());
        }

        return $session;
    }

    /**
     * @return array{date?: string, time?: string}
     */
    private static function sessionLocalParts(int $offering_id, string $session): array
    {
        try
        {
            $offering = new Offering($offering_id, DayTidyConfig::general());
            $datetime = new DateTime($session, new DateTimeZone('UTC'));

            return [
                'date' => $datetime->toTimezone(DateFormat::tech(), $offering->getTimeZone()),
                'time' => $datetime->toTimezone(TimeFormat::tech(), $offering->getTimeZone()),
            ];
        }
        catch (Exception $e)
        {
            return [];
        }
    }
}