<?php
declare(strict_types=1);

namespace Unsupervised\Schedular\Payment;

use Unsupervised\Schedular\Val;

class Payment {

	public const METHOD_CARD      = 'card';
	public const METHOD_ETRANSFER = 'etransfer';
	public const METHOD_COMP      = 'comp';

	/**
	 * All valid payment methods.
	 *
	 * @var list<string>
	 */
	public const VALID_METHODS = [ self::METHOD_CARD, self::METHOD_ETRANSFER, self::METHOD_COMP ];

	public const STATUS_PENDING  = 'pending';
	public const STATUS_PAID     = 'paid';
	public const STATUS_FAILED   = 'failed';
	public const STATUS_REFUNDED = 'refunded';

	/**
	 * All valid payment statuses.
	 *
	 * @var list<string>
	 */
	public const VALID_STATUSES = [ self::STATUS_PENDING, self::STATUS_PAID, self::STATUS_FAILED, self::STATUS_REFUNDED ];

	public const REG_LESSON     = 'lesson';
	public const REG_ENROLLMENT = 'enrollment';

	public function __construct(
		public readonly int $studentId,
		public readonly int $instructorId,
		public readonly string $registrationType,
		public readonly int $registrationId,
		public readonly float $amount,
		public readonly string $currency = 'CAD',
		public readonly string $method = self::METHOD_ETRANSFER,
		public readonly string $status = self::STATUS_PENDING,
		public readonly float $taxRate = 0.0,
		public readonly float $taxAmount = 0.0,
		public readonly float $creditApplied = 0.0,
		public readonly ?string $dueDate = null,
		public readonly ?string $periodKey = null,
		public readonly ?string $noticeBatch = null,
		public readonly ?string $etransferEmail = null,
		public readonly ?string $stripePaymentIntentId = null,
		public readonly ?string $receiptNumber = null,
		public readonly ?string $receiptSentAt = null,
		public readonly ?string $paidAt = null,
		public readonly ?string $createdAt = null,
		public readonly ?int $id = null,
	) {}

	public static function fromRow( \stdClass $row ): self {
		return new self(
			studentId:             Val::int( $row->student_id ),
			instructorId:          Val::int( $row->instructor_id ),
			registrationType:      Val::string( $row->registration_type ),
			registrationId:        Val::int( $row->registration_id ),
			amount:                Val::float( $row->amount ),
			currency:              Val::string( $row->currency ),
			method:                Val::string( $row->method ),
			status:                Val::string( $row->status ),
			taxRate:               Val::float( $row->tax_rate ),
			taxAmount:             Val::float( $row->tax_amount ),
			creditApplied:         Val::float( $row->credit_applied ?? 0 ),
			dueDate:               Val::stringOrNull( $row->due_date ?? null ),
			periodKey:             Val::stringOrNull( $row->period_key ?? null ),
			noticeBatch:           Val::stringOrNull( $row->notice_batch ?? null ),
			etransferEmail:        Val::stringOrNull( $row->etransfer_email ),
			stripePaymentIntentId: Val::stringOrNull( $row->stripe_payment_intent_id ),
			receiptNumber:         Val::stringOrNull( $row->receipt_number ),
			receiptSentAt:         Val::stringOrNull( $row->receipt_sent_at ),
			paidAt:                Val::stringOrNull( $row->paid_at ),
			createdAt:             Val::stringOrNull( $row->created_at ),
			id:                    Val::int( $row->id ),
		);
	}

	public function isPaid(): bool {
		return self::STATUS_PAID === $this->status;
	}

	/**
	 * Whether this payment was generated by the daily billing scan (weekly /
	 * monthly) rather than taken at registration. Scheduled payments carry a due
	 * date, can cover several lessons, and are never auto-voided on cancellation.
	 */
	public function isScheduled(): bool {
		return null !== $this->dueDate;
	}

	/**
	 * Amount billed including tax.
	 */
	public function total(): float {
		return round( $this->amount + $this->taxAmount, 2 );
	}

	/**
	 * What the student still owes after any account credit applied to this payment.
	 * The full `total()` less `creditApplied`, floored at zero.
	 */
	public function netDue(): float {
		return round( max( 0.0, $this->total() - $this->creditApplied ), 2 );
	}

	/**
	 * Minimal payment info embedded in registration-creation responses: enough
	 * for the front end to decide whether (and how) to run the payment step.
	 *
	 * @return array<string, mixed>
	 */
	public function toSummaryArray(): array {
		return [
			'id'     => $this->id,
			'method' => $this->method,
			'status' => $this->status,
		];
	}

	/**
	 * Returns a plain array representation of the payment.
	 *
	 * @return array<string, mixed>
	 */
	public function toArray(): array {
		return [
			'id'                => $this->id,
			'student_id'        => $this->studentId,
			'instructor_id'     => $this->instructorId,
			'registration_type' => $this->registrationType,
			'etransfer_email'   => $this->etransferEmail,
			'registration_id'   => $this->registrationId,
			'amount'            => $this->amount,
			'tax_rate'          => $this->taxRate,
			'tax_amount'        => $this->taxAmount,
			'total'             => $this->total(),
			'credit_applied'    => $this->creditApplied,
			'net_due'           => $this->netDue(),
			'currency'          => $this->currency,
			'method'            => $this->method,
			'status'            => $this->status,
			'due_date'          => $this->dueDate,
			'period_key'        => $this->periodKey,
			'notice_batch'      => $this->noticeBatch,
			'receipt_number'    => $this->receiptNumber,
			'paid_at'           => $this->paidAt,
			'created_at'        => $this->createdAt,
		];
	}
}