<?php
namespace PostFee;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

// phpcs:disable WordPress.DB.DirectDatabaseQuery -- The plugin's own table. Credits are never read from a cache.

/**
 * Posting credits a user holds from a paid plan.
 *
 * credits_total NULL means unlimited. Statuses: active, cancelling (a
 * subscription set to end at the period end), cancelled, expired, revoked.
 */
class Entitlements {

	public static function table() {
		global $wpdb;
		return $wpdb->prefix . 'postfee_entitlements';
	}

	public static function grant( $data ) {
		global $wpdb;
		$data = wp_parse_args(
			$data,
			array(
				'status'     => 'active',
				'created_at' => postfee_now(),
			)
		);
		$wpdb->insert( self::table(), $data );
		return (int) $wpdb->insert_id;
	}

	public static function get( $id ) {
		global $wpdb;
		return $wpdb->get_row( $wpdb->prepare( 'SELECT * FROM %i WHERE id = %d', self::table(), $id ) );
	}

	public static function update( $id, $data ) {
		global $wpdb;
		return $wpdb->update( self::table(), $data, array( 'id' => $id ) );
	}

	/**
	 * Entitlements a user can still post with, soonest to expire first.
	 */
	public static function usable_for_user( $user_id ) {
		global $wpdb;
		return $wpdb->get_results( $wpdb->prepare( "SELECT * FROM %i WHERE user_id = %d AND status IN ('active','cancelling') AND (expires_at IS NULL OR expires_at > %s) AND (credits_total IS NULL OR credits_used < credits_total) ORDER BY expires_at IS NULL, expires_at ASC, id ASC", self::table(), $user_id, postfee_now() ) );
	}

	/**
	 * Running subscriptions and unexpired packages, including used-up ones.
	 */
	public static function current_for_user( $user_id ) {
		global $wpdb;
		return $wpdb->get_results( $wpdb->prepare( "SELECT * FROM %i WHERE user_id = %d AND status IN ('active','cancelling') AND (expires_at IS NULL OR expires_at > %s) ORDER BY id DESC", self::table(), $user_id, postfee_now() ) );
	}

	public static function find_usable( $user_id, $post_type ) {
		foreach ( self::usable_for_user( $user_id ) as $entitlement ) {
			if ( Plans::allows_post_type( $entitlement->plan_id, $post_type ) ) {
				return $entitlement;
			}
		}
		return null;
	}

	public static function find_by_sub( $gateway, $sub_id ) {
		global $wpdb;
		return $wpdb->get_row( $wpdb->prepare( 'SELECT * FROM %i WHERE gateway = %s AND gateway_sub_id = %s ORDER BY id DESC LIMIT 1', self::table(), $gateway, $sub_id ) );
	}

	public static function find_by_order( $order_id ) {
		global $wpdb;
		return $wpdb->get_results( $wpdb->prepare( 'SELECT * FROM %i WHERE order_id = %d', self::table(), $order_id ) );
	}

	/**
	 * Credits left, or null when unlimited.
	 */
	public static function remaining( $entitlement ) {
		return null === $entitlement->credits_total ? null : max( 0, (int) $entitlement->credits_total - (int) $entitlement->credits_used );
	}

	/**
	 * Spends one credit. The WHERE clause re-checks availability so two
	 * simultaneous submissions cannot both spend the last credit.
	 */
	public static function consume( $id ) {
		global $wpdb;
		return 1 === $wpdb->query( $wpdb->prepare( "UPDATE %i SET credits_used = credits_used + 1 WHERE id = %d AND status IN ('active','cancelling') AND (expires_at IS NULL OR expires_at > %s) AND (credits_total IS NULL OR credits_used < credits_total)", self::table(), $id, postfee_now() ) );
	}

	/**
	 * Gives one spent credit back.
	 */
	public static function release( $id ) {
		global $wpdb;
		return 1 === $wpdb->query( $wpdb->prepare( 'UPDATE %i SET credits_used = credits_used - 1 WHERE id = %d AND credits_used > 0', self::table(), $id ) );
	}

	/**
	 * Starts a new subscription period: credits reset and access extended.
	 */
	public static function renew( $id, $period_end ) {
		return self::update(
			$id,
			array(
				'credits_used' => 0,
				'expires_at'   => gmdate( 'Y-m-d H:i:s', $period_end + DAY_IN_SECONDS ),
			)
		);
	}

	/**
	 * @return object[] The entitlements that just expired.
	 */
	public static function expire_due() {
		global $wpdb;
		$due = $wpdb->get_results( $wpdb->prepare( "SELECT * FROM %i WHERE status IN ('active','cancelling') AND expires_at IS NOT NULL AND expires_at <= %s", self::table(), postfee_now() ) );
		foreach ( $due as $entitlement ) {
			self::update( $entitlement->id, array( 'status' => 'expired' ) );
		}
		return $due;
	}
}