class OrderMeta
{

    const CHARGE_PERMISSION_ID = 'amazonChargePermissionId';
    const CHARGE_ID = 'amazonChargeId';
    const REFUND_ID = 'amazonRefundId';
    const CHARGE_STATE = 'amazonChargeState';
    const REFUND_STATE = 'amazonRefundState';
    const LINK_KEY = 'amazonLinkKey';
    const PAYMENT_CURRENCY = 'amazonPaymentCurrency';
    const MOST_RECENT_TRANS_AMOUNT = 'amazonMostRecentTransAmount';
    const IPN_NOTIFICATION_IDS = 'amazonIpnNotificationIds';

    /**
     * Welcart order ID
     *
     * @var int
     */
    private $orderid;

    /**
     * Payment currency
     *
     * @var string
     */
    private $paymentCurrency;

    /**
     * Amount of the most recent transaction that involved a payment of some kind
     *
     * @var int|string
     */
    private $mostRecentTransactionAmount;

    /**
     * `chargePermissionId` returned by `Get Checkout Session` API
     *
     * @var string
     */
    private $chargePermissionId;

    /**
     * `chargeId` returned by `Get Checkout Session` API
     *
     * @var string|null
     */
    private $chargeId;

    /**
     * `refundId` returned by `Create Refund` API
     *
     * @var string|null
     */
    private $refundId = null;

    /**
     * Link key for the 直前決済ログ entry
     *
     * @var string|null
     */
    private $linkKey = null;

    /**
     * Charge state object for state tracking
     *
     * @var Charge\State|null
     */
    private $chargeState;

    /**
     * Refund state object for state tracking
     *
     * @var Refund\State|null
     */
    private $refundState = null;

    /**
     * List of processed IPN ids
     *
     * @var string[]
     */
    private $ipnNotificationIds = [];

    /**
     * Constructs an AmazonPay order object from an existing transaction
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @global \usc_e_shop $usces
     * @param int $orderid
     * @return void
     * @throws InvalidArgumentException Thrown if no such Amazon Pay order exists for the given order ID.
     */
    public function __construct($orderid) {
        global $usces;

        $this->orderid = (int)$orderid;
        $this->chargeId = $usces->get_order_meta_value(self::CHARGE_ID, $this->orderid);
        $this->chargePermissionId = $usces->get_order_meta_value(self::CHARGE_PERMISSION_ID, $this->orderid);
        $this->refundId = $usces->get_order_meta_value(self::REFUND_ID, $this->orderid);
        $this->linkKey = $usces->get_order_meta_value(self::LINK_KEY, $this->orderid);
        $this->paymentCurrency = $usces->get_order_meta_value(self::PAYMENT_CURRENCY, $this->orderid);
        $ipnNotificationIds = $usces->get_order_meta_value(self::IPN_NOTIFICATION_IDS, $this->orderid);
        $this->mostRecentTransactionAmount = $usces->get_order_meta_value(
            self::MOST_RECENT_TRANS_AMOUNT,
            $this->orderid
        );
        if (empty($this->chargePermissionId)) {
            throw new InvalidArgumentException('No such Amazon Pay order exists for the given order ID');
        }
        if (empty($ipnNotificationIds)) {
            $this->ipnNotificationIds = [];
        } else {
            $this->ipnNotificationIds = json_decode($ipnNotificationIds);
        }

        if (!empty($this->chargeId)) {
            $chargeState = json_decode($usces->get_order_meta_value(self::CHARGE_STATE, $this->orderid), true);
            $this->chargeState = new Charge\State(
                $chargeState['state'],
                $chargeState['reasonCode'],
                $chargeState['reasonDescription']
            );
        }

        if (!empty($this->refundId)) {
            $refundState = json_decode($usces->get_order_meta_value(self::REFUND_STATE, $this->orderid), true);
            $this->refundState = new Refund\State(
                $refundState['state'],
                $refundState['reasonCode'],
                $refundState['reasonDescription']
            );
        }
    }

    /**
     * Saves Amazon Pay order meta data with `Get Checkout Session` response and charge
     * state after a successful purchase
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @global \usc_e_shop $usces
     * @param array             $response
     * @param int               $orderid
     * @param int|string        $amount authorize or capture amount
     * @param string            $currencyCode
     * @param Charge\State|null $chargeState
     * @return void
     */
    public static function saveOrderMetaDataFromCheckoutSession(
        array $response,
        $orderid,
        $amount,
        $currencyCode,
        Charge\State $chargeState = null
    ) {
        global $usces;

        $chargePermissionId = $response['chargePermissionId'];
        $chargeId = isset($response['chargeId']) ? $response['chargeId'] : null;
        $serializedChargeState = $chargeState !== null ? json_encode($chargeState) : null;

        $usces->set_order_meta_value(self::CHARGE_ID, $chargeId, $orderid);
        $usces->set_order_meta_value(self::CHARGE_PERMISSION_ID, $chargePermissionId, $orderid);
        $usces->set_order_meta_value(self::LINK_KEY, $response['checkoutSessionId'], $orderid);
        $usces->set_order_meta_value(self::CHARGE_STATE, $serializedChargeState, $orderid);
        $usces->set_order_meta_value(self::MOST_RECENT_TRANS_AMOUNT, $amount, $orderid);
        $usces->set_order_meta_value(self::PAYMENT_CURRENCY, $currencyCode, $orderid);
        $usces->set_order_meta_value('wc_trans_id', $chargePermissionId, $orderid);

        if ($chargeState !== null) {
            $state = $chargeState->getState();
            if (!empty(Charge\State::STATE_TO_LOG_ACTION[$state])) {
                (new Logger())->logApiResponse(new Log(
                    $chargePermissionId,
                    Charge\State::STATE_TO_LOG_ACTION[$state],
                    Log::RESPONSE_OK,
                    $amount
                ));
            }
        } else {
            (new Logger())->logApiResponse(new Log(
                $chargePermissionId,
                Log::ACTION_DEFERRED_AUTHORIZE,
                Log::RESPONSE_OK,
                $amount
            ));
        }
    }

    /**
     * Updates charge state
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @global \usc_e_shop $usces
     * @param Charge\State $chargeState
     * @return void
     */
    public function updateChargeState(Charge\State $chargeState) {
        global $usces;

        $this->chargeState = $chargeState;
        $usces->set_order_meta_value(self::CHARGE_STATE, json_encode($this->chargeState), $this->orderid);
    }

    /**
     * Updates refund state
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @global \usc_e_shop $usces
     * @param Refund\State    $refundState
     * @param int|string|null $refundAmount
     * @return void
     */
    public function updateRefundState(Refund\State $refundState, $refundAmount = null) {
        global $usces;

        $this->refundState = $refundState;
        $usces->set_order_meta_value(self::REFUND_STATE, json_encode($this->refundState), $this->orderid);
        if ($refundAmount) {
            $this->mostRecentTransactionAmount = $refundAmount;
            $usces->set_order_meta_value(self::MOST_RECENT_TRANS_AMOUNT, $refundAmount, $this->orderid);
        }
    }

    /**
     * Adds IPN notification ID to list if it doesn't already exist
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @global \usc_e_shop $usces
     * @param string $id
     * @return void
     */
    public function updateNotificationIds($id) {
        global $usces;

        if (!in_array($id, $this->ipnNotificationIds, true)) {
            $this->ipnNotificationIds[] = $id;
            $usces->set_order_meta_value(
                self::IPN_NOTIFICATION_IDS,
                json_encode($this->ipnNotificationIds),
                $this->orderid
            );
        }
    }

    /**
     * Returns the current transaction state
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @return TransactionState
     */
    public function getTransactionState() {
        if (!empty($this->refundId)) {
            $this->refundState->setChargePermissionId($this->getChargePermissionId());
            return $this->refundState;
        } elseif (!empty($this->chargeId)) {
            $this->chargeState->setChargePermissionId($this->getChargePermissionId());
            return $this->chargeState;
        } else {
            $deferred = new DeferredAuthorize\State(DeferredAuthorize\State::DEFERRED_AUTHORIZE);
            $deferred->setChargePermissionId($this->getChargePermissionId());
            return $deferred;
        }
    }

    /**
     * Sets Refund state object for the order
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @global \usc_e_shop $usces
     * @param Refund\State $refundState
     * @param string       $refundId
     * @param int|string   $refundAmount
     * @return void
     */
    public function setRefundState(Refund\State $refundState, $refundId, $refundAmount) {
        global $usces;

        $this->refundState = $refundState;
        $this->refundId = $refundId;
        $this->mostRecentTransactionAmount = $refundAmount;

        $usces->set_order_meta_value(self::REFUND_STATE, json_encode($this->refundState), $this->orderid);
        $usces->set_order_meta_value(self::REFUND_ID, $this->refundId, $this->orderid);
        $usces->set_order_meta_value(self::MOST_RECENT_TRANS_AMOUNT, $refundAmount, $this->orderid);
    }

    /**
     * Sets Charge state object for the order
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @global \usc_e_shop $usces
     * @param Charge\State $chargeState
     * @param string       $chargeId
     * @param int|string   $chargeAmount
     * @return void
     */
    public function setChargeState(Charge\State $chargeState, $chargeId, $chargeAmount) {
        global $usces;

        $this->chargeState = $chargeState;
        $this->chargeId = $chargeId;
        $this->mostRecentTransactionAmount = $chargeAmount;

        $usces->set_order_meta_value(self::CHARGE_STATE, json_encode($this->chargeState), $this->orderid);
        $usces->set_order_meta_value(self::CHARGE_ID, $this->chargeId, $this->orderid);
        $usces->set_order_meta_value(self::MOST_RECENT_TRANS_AMOUNT, $chargeAmount, $this->orderid);
    }

    /**
     * Getter for `orderid`
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @return int
     */
    public function getOrderId() {
        return $this->orderid;
    }

    /**
     * Getter for `chargePermissionId`
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @return string
     */
    public function getChargePermissionId() {
        return $this->chargePermissionId;
    }

    /**
     * Getter for `chargeId`
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @return string|null
     */
    public function getChargeId() {
        return $this->chargeId;
    }

    /**
     * Getter for `refundId`
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @return string|null
     */
    public function getRefundId() {
        return $this->refundId;
    }

    /**
     * Getter for `linkKey`
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @return string|null
     */
    public function getLinkKey() {
        return $this->linkKey;
    }

    /**
     * Getter for `chargeState`
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @return Charge\State|null
     */
    public function getChargeState() {
        return $this->chargeState;
    }

    /**
     * Getter for `refundState`
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @return Refund\State|null
     */
    public function getRefundState() {
        return $this->refundState;
    }

    /**
     * Getter for `paymentCurrency`
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @return string
     */
    public function getPaymentCurrency() {
        return $this->paymentCurrency;
    }

    /**
     * Getter for `mostRecentTransactionAmount`
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @return int|string
     */
    public function getMostRecentTransactionAmount() {
        return $this->mostRecentTransactionAmount;
    }

    /**
     * Getter for `ipnNotificationIds`
     *
     * @author Evan D Shaw <evandanielshaw@gmail.com>
     * @return string[]
     */
    public function getIpnNotificationIds() {
        return $this->ipnNotificationIds;
    }
}