<?php
/**
 * Shared helpers: settings, dates, the customer's choice, order values.
 *
 * Most checks take a "context" array so add-ons can vary the rules:
 *   mode          'delivery' | 'pickup'
 *   location      pickup location id
 *   exclude_order order id ignored when counting (rescheduling an existing order)
 *   items         array of WC_Product (cart or order contents) for product rules
 */

defined( 'ABSPATH' ) || exit;

define( 'DAYSLOT_META', '_dayslot_event_date' );
define( 'DAYSLOT_SLOT_META', '_dayslot_time_slot' );
define( 'DAYSLOT_VARIANT_META', '_dayslot_variant' );
define( 'DAYSLOT_MODE_META', '_dayslot_mode' );
define( 'DAYSLOT_LOCATION_META', '_dayslot_location' );
define( 'DAYSLOT_PRICE_META', '_dayslot_price' );

/**
 * Pro features on/off. The Pro add-on switches this on.
 */
function dayslot_is_pro() {
	return (bool) apply_filters( 'dayslot_is_pro', false );
}

/**
 * URL of a plugin asset: the minified copy unless SCRIPT_DEBUG is on.
 */
function dayslot_asset( $file, $base_dir = DAYSLOT_DIR, $base_url = DAYSLOT_URL ) {
	if ( ! ( defined( 'SCRIPT_DEBUG' ) && SCRIPT_DEBUG ) ) {
		$min = preg_replace( '/\.(js|css)$/', '.min.$1', $file );
		if ( file_exists( $base_dir . $min ) ) {
			return $base_url . $min;
		}
	}
	return $base_url . $file;
}

/**
 * Is a feature switched on (Settings → Features)? Everything is on by default.
 */
function dayslot_feature_on( $id ) {
	$settings = get_option( 'dayslot_settings', array() );
	$off      = is_array( $settings ) && isset( $settings['disabled_features'] ) ? (array) $settings['disabled_features'] : array();
	return ! in_array( $id, $off, true );
}

/**
 * Default delivery options ("variants"): what the customer can choose in the time step.
 */
function dayslot_default_variants() {
	return array(
		array(
			'id'            => 'window',
			'type'          => 'interval',
			'label'         => __( '2-hour window', 'dayslot' ),
			'note'          => '',
			'from'          => '08:00',
			'to'            => '20:00',
			'length'        => 120,
			'step'          => 0,
			'limit'         => 2,
			'price_weekday' => 20,
			'price_sunday'  => 50,
			'price_holiday' => '',
			'enabled'       => 'yes',
		),
		array(
			'id'            => 'exact',
			'type'          => 'exact',
			'label'         => __( 'Exact time', 'dayslot' ),
			'note'          => '',
			'from'          => '08:00',
			'to'            => '21:00',
			'length'        => 0,
			'step'          => 15,
			'limit'         => 0,
			'price_weekday' => 50,
			'price_sunday'  => 70,
			'price_holiday' => '',
			'enabled'       => 'yes',
		),
		array(
			'id'            => 'night',
			'type'          => 'night',
			'label'         => __( 'Night', 'dayslot' ),
			'note'          => '',
			'from'          => '21:00',
			'to'            => '08:00',
			'length'        => 0,
			'step'          => 15,
			'limit'         => 1,
			'price_weekday' => 70,
			'price_sunday'  => 100,
			'price_holiday' => '',
			'enabled'       => 'yes',
		),
	);
}

/**
 * Default settings (translated). Add-ons add theirs with the "dayslot_default_settings" filter.
 */
function dayslot_defaults() {
	return apply_filters(
		'dayslot_default_settings',
		array(
			// General.
			'max_per_day'           => 5,
			'min_days'              => 1,
			'max_days'              => 365,
			'closed_weekdays'       => array(),
			'blocked_dates'         => '',
			'holidays'              => '',
			'holiday_country'       => '',
			'required'              => 'yes',
			'auto_select'           => 'no',
			'hide_virtual'          => 'yes',
			'statuses'              => array( 'processing', 'on-hold', 'completed' ),
			'notify_customer'       => 'yes',
			// Delivery options.
			'variants'              => dayslot_default_variants(),
			'slot_prep_minutes'     => 60,
			'blocked_slots'         => '',
			'shipping_title'        => __( 'Delivery', 'dayslot' ),
			'hide_other_shipping'   => 'yes',
			'free_above'            => 0,
			'free_always'           => 'no',
			'small_below'           => 0,
			'small_fee'             => 0,
			// Checkout texts and placement.
			'placement'             => 'after_address',
			'method_label'          => __( 'Delivery method', 'dayslot' ),
			'label'                 => __( 'Delivery date', 'dayslot' ),
			'time_label'            => __( 'Delivery time', 'dayslot' ),
			'delivery_text'         => __( 'Delivery', 'dayslot' ),
			'required_message'      => __( 'Please choose the delivery date.', 'dayslot' ),
			'unavailable_message'   => __( 'Sorry, this date is not available. Please choose another one.', 'dayslot' ),
			'slot_required_message' => __( 'Please choose the delivery time.', 'dayslot' ),
			'slot_full_message'     => __( 'Sorry, this time is no longer available. Please choose another one.', 'dayslot' ),
			'full_times'            => 'contact',
			/* translators: {times}: booked times, e.g. 10:00–12:00 */
			'full_contact'          => __( 'Already booked: {times}. Want delivery at that time? Please contact us.', 'dayslot' ),
			// Appearance.
			'style'                 => array(),
		)
	);
}

/**
 * Plugin settings merged with defaults.
 */
function dayslot_get_settings() {
	static $defaults = array();
	static $cache    = null;
	static $raw      = null;
	static $locale   = null;
	static $busy     = false;

	$saved = get_option( 'dayslot_settings', array() );
	$here  = determine_locale();
	if ( null !== $cache && $saved === $raw && $here === $locale ) {
		return $cache;
	}
	// Defaults per language: multilingual shops switch the language during a page.
	if ( ! isset( $defaults[ $here ] ) ) {
		$defaults[ $here ] = dayslot_defaults();
	}
	$saved = is_array( $saved ) ? $saved : array();
	if ( $busy ) {
		return wp_parse_args( $saved, $defaults[ $here ] );
	}
	$busy   = true;
	$cache  = wp_parse_args( (array) apply_filters( 'dayslot_saved_settings', $saved ), $defaults[ $here ] );
	$busy   = false;
	$raw    = get_option( 'dayslot_settings', array() );
	$locale = $here;
	return $cache;
}

/**
 * Save settings (merging into what is stored).
 */
function dayslot_update_settings( $changes ) {
	$settings = get_option( 'dayslot_settings', array() );
	$settings = is_array( $settings ) ? $settings : array();
	update_option( 'dayslot_settings', array_merge( $settings, $changes ), true );
}

/**
 * Normalise a context array.
 */
function dayslot_ctx( $ctx = array() ) {
	$ctx = wp_parse_args(
		is_array( $ctx ) ? $ctx : array(),
		array(
			'mode'          => 'delivery',
			'location'      => '',
			'exclude_order' => 0,
			'items'         => null,
		)
	);
	if ( 'pickup' !== $ctx['mode'] ) {
		$ctx['mode'] = 'delivery';
		if ( ! dayslot_branches() ) {
			$ctx['location'] = '';
		}
	}
	return $ctx;
}

/**
 * Branches (Pro pickup points chosen first): every point also delivers, with its own hours and places.
 */
function dayslot_branches() {
	return (bool) apply_filters( 'dayslot_branches', false );
}

/**
 * Capacity pool key of a context: "delivery" or "pickup:<location>".
 */
function dayslot_pool_key( $ctx ) {
	if ( 'pickup' === $ctx['mode'] ) {
		return 'pickup:' . $ctx['location'];
	}
	return dayslot_branches() && '' !== (string) $ctx['location'] ? 'delivery:' . $ctx['location'] : 'delivery';
}

/**
 * Parse a Y-m-d string into a DateTimeImmutable in the site time zone, or null.
 */
function dayslot_parse_date( $date ) {
	if ( ! is_string( $date ) || ! preg_match( '/^\d{4}-\d{2}-\d{2}$/', $date ) ) {
		return null;
	}
	$dt = DateTimeImmutable::createFromFormat( '!Y-m-d', $date, wp_timezone() );
	return ( $dt && $dt->format( 'Y-m-d' ) === $date ) ? $dt : null;
}

/**
 * Today at midnight, site time zone.
 */
function dayslot_today() {
	return current_datetime()->setTime( 0, 0 );
}

/**
 * Dates from a textarea (one per line or separated by commas): array of Y-m-d.
 */
function dayslot_parse_date_list( $text ) {
	$dates = array();
	foreach ( preg_split( '/[\s,;]+/', (string) $text ) as $line ) {
		$line = trim( $line );
		if ( dayslot_parse_date( $line ) ) {
			$dates[] = $line;
		}
	}
	return array_values( array_unique( $dates ) );
}

/**
 * Manually blocked dates (array of Y-m-d).
 */
function dayslot_blocked_dates() {
	return dayslot_parse_date_list( dayslot_get_settings()['blocked_dates'] );
}

/**
 * Month and weekday names in the plugin's own translations, so the calendar always speaks the same language as
 * the rest of the plugin (WordPress's own names follow the WordPress language, which may differ).
 * Weekdays are keyed 0 = Sunday … 6 = Saturday; "dateMonths" are for a day inside a date ("%d October" →
 * "22 października" in Polish).
 */
function dayslot_calendar_words() {
	return array(
		'months'     => array( __( 'January', 'dayslot' ), __( 'February', 'dayslot' ), __( 'March', 'dayslot' ), __( 'April', 'dayslot' ), __( 'May', 'dayslot' ), __( 'June', 'dayslot' ), __( 'July', 'dayslot' ), __( 'August', 'dayslot' ), __( 'September', 'dayslot' ), __( 'October', 'dayslot' ), __( 'November', 'dayslot' ), __( 'December', 'dayslot' ) ),
		/* translators: %d: day of the month; the month as used inside a date */
		'dateMonths' => array( __( '%d January', 'dayslot' ), __( '%d February', 'dayslot' ), __( '%d March', 'dayslot' ), __( '%d April', 'dayslot' ), __( '%d May', 'dayslot' ), __( '%d June', 'dayslot' ), __( '%d July', 'dayslot' ), __( '%d August', 'dayslot' ), __( '%d September', 'dayslot' ), __( '%d October', 'dayslot' ), __( '%d November', 'dayslot' ), __( '%d December', 'dayslot' ) ),
		'days'       => array( __( 'Sunday', 'dayslot' ), __( 'Monday', 'dayslot' ), __( 'Tuesday', 'dayslot' ), __( 'Wednesday', 'dayslot' ), __( 'Thursday', 'dayslot' ), __( 'Friday', 'dayslot' ), __( 'Saturday', 'dayslot' ) ),
		'daysShort'  => array( __( 'Sun', 'dayslot' ), __( 'Mon', 'dayslot' ), __( 'Tue', 'dayslot' ), __( 'Wed', 'dayslot' ), __( 'Thu', 'dayslot' ), __( 'Fri', 'dayslot' ), __( 'Sat', 'dayslot' ) ),
	);
}

/**
 * Human-readable date in the site language and date format.
 */
function dayslot_format_date( $date ) {
	$dt = dayslot_parse_date( $date );
	if ( ! $dt ) {
		return '';
	}
	// The site's date format, with month and weekday names from the plugin's translations
	// ("j F" becomes "22 października" in Polish, not "22 październik").
	$words = dayslot_calendar_words();
	$month = (int) $dt->format( 'n' ) - 1;
	$wday  = (int) $dt->format( 'w' );
	$marks = array();
	// Languages where the month changes inside a date ("25 października", "25. Oktober") get that form also
	// with a "month day, year" format: "F j, Y" would give "Październik 25, 2026".
	$in_date = str_replace( '%d', $dt->format( 'j' ), $words['dateMonths'][ $month ] );
	$changes = '%d ' . $words['months'][ $month ] !== $words['dateMonths'][ $month ];
	$fmt     = preg_replace_callback(
		'/\\\\.|F jS?,?|j F|[FMlD]/',
		function ( $m ) use ( &$marks, $dt, $words, $month, $wday, $in_date, $changes ) {
			if ( '\\' === $m[0][0] ) {
				return $m[0];
			}
			$values = array(
				'j F' => $in_date,
				'F'   => $words['months'][ $month ],
				'M'   => mb_substr( $words['months'][ $month ], 0, 3 ),
				'l'   => $words['days'][ $wday ],
				'D'   => $words['daysShort'][ $wday ],
			);
			if ( ! isset( $values[ $m[0] ] ) ) {
				// Formats like F j, F jS and "F j," (with a comma).
				$values[ $m[0] ] = $changes ? $in_date : $words['months'][ $month ] . ' ' . $dt->format( false !== strpos( $m[0], 'S' ) ? 'jS' : 'j' ) . ( ',' === substr( $m[0], -1 ) ? ',' : '' );
			}
			$key           = '{' . count( $marks ) . '}';
			$marks[ $key ] = $values[ $m[0] ];
			return '\\' . implode( '\\', str_split( $key ) );
		},
		(string) get_option( 'date_format', 'j F Y' )
	);
	return strtr( $dt->format( $fmt ), $marks );
}

/**
 * Validate "HH:MM".
 */
function dayslot_valid_time( $time ) {
	return is_string( $time ) && (bool) preg_match( '/^([01]\d|2[0-3]):[0-5]\d$/', $time );
}

/**
 * Valid slot key: "HH:MM-HH:MM" (a window) or "HH:MM" (an exact time).
 */
function dayslot_valid_slot_key( $key ) {
	if ( ! is_string( $key ) ) {
		return false;
	}
	$parts = explode( '-', $key );
	if ( 1 === count( $parts ) ) {
		return dayslot_valid_time( $parts[0] );
	}
	return 2 === count( $parts ) && dayslot_valid_time( $parts[0] ) && dayslot_valid_time( $parts[1] );
}

/**
 * "10:00-12:00" → "10:00 – 12:00", "10:30" → "10:30".
 */
function dayslot_format_slot( $key ) {
	$parts = explode( '-', (string) $key );
	return 2 === count( $parts ) ? $parts[0] . ' – ' . $parts[1] : (string) $key;
}

/**
 * Date plus time, e.g. "24 października 2026, 10:00 – 12:00".
 */
function dayslot_format_date_slot( $date, $slot ) {
	$out = dayslot_format_date( $date );
	if ( $slot ) {
		$out .= ', ' . dayslot_format_slot( $slot );
	}
	return $out;
}

/**
 * Minutes since midnight for "HH:MM".
 */
function dayslot_minutes( $time ) {
	$p = explode( ':', (string) $time );
	return 2 === count( $p ) ? (int) $p[0] * 60 + (int) $p[1] : 0;
}

/**
 * "HH:MM" for minutes since midnight (wraps at 24h).
 */
function dayslot_time_from_minutes( $minutes ) {
	$minutes = ( (int) $minutes % 1440 + 1440 ) % 1440;
	return sprintf( '%02d:%02d', intdiv( $minutes, 60 ), $minutes % 60 );
}

/**
 * Plain-text money, e.g. "20 zł".
 */
function dayslot_money( $amount ) {
	return html_entity_decode( wp_strip_all_tags( wc_price( $amount ) ), ENT_QUOTES, 'UTF-8' );
}

/**
 * Earliest bookable day offset (days from today) for a context.
 */
function dayslot_min_days( $ctx = array() ) {
	return max( 0, (int) apply_filters( 'dayslot_min_days', (int) dayslot_get_settings()['min_days'], dayslot_ctx( $ctx ) ) );
}

/**
 * Daily order limit for a context (0 = unlimited).
 */
function dayslot_daily_limit( $ctx = array() ) {
	return max( 0, (int) apply_filters( 'dayslot_daily_limit', (int) dayslot_get_settings()['max_per_day'], dayslot_ctx( $ctx ) ) );
}

/**
 * Daily limit on one date (Pro special dates can have their own).
 */
function dayslot_day_limit( $date, $ctx = array() ) {
	$ctx = dayslot_ctx( $ctx );
	return max( 0, (int) apply_filters( 'dayslot_day_limit', dayslot_daily_limit( $ctx ), $date, $ctx ) );
}

/**
 * Delivery modes the customer can choose from: array( 'delivery' => label, ... ).
 * The Pro add-on adds pickup.
 */
function dayslot_modes() {
	return apply_filters( 'dayslot_modes', array( 'delivery' => dayslot_get_settings()['delivery_text'] ) );
}

// --------------------------------------------------------------------------
// Cart / order products
// --------------------------------------------------------------------------

/**
 * Products in the current cart.
 *
 * @return WC_Product[]
 */
function dayslot_cart_products() {
	$out = array();
	if ( function_exists( 'WC' ) && WC()->cart ) {
		foreach ( WC()->cart->get_cart() as $item ) {
			if ( ! empty( $item['data'] ) && is_a( $item['data'], 'WC_Product' ) ) {
				$out[] = $item['data'];
			}
		}
	}
	return $out;
}

/**
 * Products in an order.
 *
 * @return WC_Product[]
 */
function dayslot_order_products( $order ) {
	$out = array();
	foreach ( $order->get_items() as $item ) {
		$product = is_callable( array( $item, 'get_product' ) ) ? $item->get_product() : null;
		if ( $product ) {
			$out[] = $product;
		}
	}
	return $out;
}

/**
 * Do these products need a delivery date at all?
 */
function dayslot_products_need_date( $products ) {
	if ( ! $products ) {
		return true;
	}
	$needs = true;
	if ( 'yes' === dayslot_get_settings()['hide_virtual'] ) {
		$needs = false;
		foreach ( $products as $product ) {
			if ( ! $product->is_virtual() ) {
				$needs = true;
				break;
			}
		}
	}
	return (bool) apply_filters( 'dayslot_products_need_date', $needs, $products );
}

function dayslot_cart_needs_date() {
	return dayslot_products_need_date( dayslot_cart_products() );
}

function dayslot_order_needs_date( $order ) {
	return dayslot_products_need_date( dayslot_order_products( $order ) );
}

// --------------------------------------------------------------------------
// The customer's choice (session) — used for the shipping price and live recalculation
// --------------------------------------------------------------------------

/**
 * Clean a choice array (POST, Store API, AJAX, session).
 */
function dayslot_read_choice( $src ) {
	$src    = is_array( $src ) ? $src : array();
	$get    = function ( $key ) use ( $src ) {
		return isset( $src[ $key ] ) && is_scalar( $src[ $key ] ) ? sanitize_text_field( wp_unslash( (string) $src[ $key ] ) ) : '';
	};
	$mode   = 'pickup' === $get( 'mode' ) ? 'pickup' : 'delivery';
	$date   = $get( 'date' );
	$slot   = $get( 'slot' );
	$choice = array(
		'date'     => dayslot_parse_date( $date ) ? $date : '',
		'slot'     => dayslot_valid_slot_key( $slot ) ? $slot : '',
		'variant'  => sanitize_key( $get( 'variant' ) ),
		'mode'     => $mode,
		'location' => 'pickup' === $mode || dayslot_branches() ? sanitize_key( $get( 'location' ) ) : '',
	);
	if ( '' === $choice['date'] && '' !== $date ) {
		$choice['date'] = 'invalid';
	}
	return apply_filters( 'dayslot_read_choice', $choice, $src );
}

function dayslot_empty_choice() {
	return array(
		'date'     => '',
		'slot'     => '',
		'variant'  => '',
		'mode'     => 'delivery',
		'location' => '',
	);
}

function dayslot_session_get() {
	$data = ( function_exists( 'WC' ) && WC()->session ) ? WC()->session->get( 'dayslot_choice' ) : null;
	return wp_parse_args( is_array( $data ) ? $data : array(), dayslot_empty_choice() );
}

function dayslot_session_set( $choice ) {
	if ( ! function_exists( 'WC' ) || ! WC()->session ) {
		return;
	}
	if ( 'invalid' === $choice['date'] ) {
		$choice['date'] = '';
	}
	WC()->session->set( 'dayslot_choice', $choice );
}

/**
 * Context for a customer choice + products.
 */
function dayslot_ctx_for_choice( $choice, $products = null, $exclude_order = 0 ) {
	return dayslot_ctx(
		array(
			'mode'          => $choice['mode'],
			'location'      => $choice['location'],
			'items'         => $products,
			'exclude_order' => $exclude_order,
		)
	);
}

/**
 * Store a choice on an order (does not call save()).
 */
function dayslot_save_order_values( $order, $choice ) {
	$choice = wp_parse_args( $choice, dayslot_empty_choice() );
	if ( ! dayslot_parse_date( $choice['date'] ) ) {
		return;
	}
	$order->update_meta_data( DAYSLOT_META, $choice['date'] );
	if ( dayslot_valid_slot_key( $choice['slot'] ) ) {
		$order->update_meta_data( DAYSLOT_SLOT_META, $choice['slot'] );
	} else {
		$order->delete_meta_data( DAYSLOT_SLOT_META );
	}
	if ( $choice['variant'] ) {
		$order->update_meta_data( DAYSLOT_VARIANT_META, $choice['variant'] );
	} else {
		$order->delete_meta_data( DAYSLOT_VARIANT_META );
	}
	if ( 'pickup' === $choice['mode'] ) {
		$order->update_meta_data( DAYSLOT_MODE_META, 'pickup' );
		$order->update_meta_data( DAYSLOT_LOCATION_META, sanitize_key( $choice['location'] ) );
	} else {
		$order->delete_meta_data( DAYSLOT_MODE_META );
		if ( dayslot_branches() && $choice['location'] ) {
			$order->update_meta_data( DAYSLOT_LOCATION_META, sanitize_key( $choice['location'] ) );
		} else {
			$order->delete_meta_data( DAYSLOT_LOCATION_META );
		}
	}
	do_action( 'dayslot_order_values_saved', $order, $choice );
}

/**
 * The choice stored on an order.
 */
function dayslot_order_choice( $order ) {
	$mode = 'pickup' === $order->get_meta( DAYSLOT_MODE_META ) ? 'pickup' : 'delivery';
	return array(
		'date'     => (string) $order->get_meta( DAYSLOT_META ),
		'slot'     => (string) $order->get_meta( DAYSLOT_SLOT_META ),
		'variant'  => (string) $order->get_meta( DAYSLOT_VARIANT_META ),
		'mode'     => $mode,
		'location' => 'pickup' === $mode || dayslot_branches() ? (string) $order->get_meta( DAYSLOT_LOCATION_META ) : '',
	);
}

/**
 * Simple per-IP rate limit. Returns false when $max hits within $window seconds were exceeded.
 */
function dayslot_rate_limit( $bucket, $max, $window = HOUR_IN_SECONDS ) {
	$ip  = isset( $_SERVER['REMOTE_ADDR'] ) ? sanitize_text_field( wp_unslash( $_SERVER['REMOTE_ADDR'] ) ) : '';
	$key = 'dayslot_rl_' . md5( $bucket . '|' . $ip );
	$hit = (int) get_transient( $key );
	if ( $hit >= $max ) {
		return false;
	}
	set_transient( $key, $hit + 1, $window );
	return true;
}

/**
 * Tags and attributes of form controls built in code (admin), for wp_kses() before they are printed.
 */
function dayslot_form_tags() {
	$common = array(
		'class'      => true,
		'id'         => true,
		'name'       => true,
		'value'      => true,
		'style'      => true,
		'aria-label' => true,
		'data-*'     => true,
	);
	return array(
		'input'    => array_merge(
			$common,
			array(
				'type'        => true,
				'placeholder' => true,
				'required'    => true,
				'min'         => true,
				'max'         => true,
				'step'        => true,
				'inputmode'   => true,
				'checked'     => true,
				'disabled'    => true,
			)
		),
		'select'   => $common,
		'option'   => array(
			'value'    => true,
			'selected' => true,
			'disabled' => true,
		),
		'optgroup' => array( 'label' => true ),
		'textarea' => array_merge( $common, array( 'rows' => true ) ),
		'span'     => $common,
		'small'    => $common,
	);
}