import type {
	BillingBehavior,
	CancelAction,
	CheckoutMode,
	Entitlement,
	FeatureOptions,
	FreeTrial,
	Price,
	TrialOnEnd,
} from "@autumn/shared";
import type { PaymentBehaviorIntent } from "@models/billingModels/context/paymentBehaviorIntent";
import type { TransitionConfig } from "@models/billingModels/context/transitionConfig";
import type { DbInvoiceLineItem } from "@models/cusModels/invoiceModels/invoiceLineItemTable";
import type { EntInterval } from "@models/productModels/intervals/entitlementInterval";
import type Stripe from "stripe";
import { z } from "zod/v4";
import type { FullCustomer } from "../../cusModels/fullCusModel";
import type { FullProduct } from "../../productModels/productModels";
import type { StripeDiscountWithCoupon } from "../stripe/stripeDiscountWithCoupon";

const InvoiceModeSchema = z.object({
	finalizeInvoice: z.boolean().default(false),
	enableProductImmediately: z.boolean().default(true),
	footer: z.string().optional(),
	memo: z.string().optional(),
	daysUntilDue: z.number().optional(),
});

export type InvoiceMode = z.infer<typeof InvoiceModeSchema>;

export enum BillingVersion {
	V1 = "v1",
	V2 = "v2",
}

export const LATEST_BILLING_VERSION = BillingVersion.V2;
export interface TrialContext {
	freeTrial?: FreeTrial | null;
	trialEndsAt: number | null;
	customFreeTrial?: FreeTrial;
	appliesToBilling: boolean;
	cardRequired: boolean;
	onEnd?: TrialOnEnd;
}

export interface AnchorResetRefund {
	noPartialRefund: boolean;
	refundCycle?: {
		interval: EntInterval;
		intervalCount: number;
	};
}

export interface BillingContext {
	fullCustomer: FullCustomer;
	fullProducts: FullProduct[];

	featureQuantities: FeatureOptions[];
	adjustableFeatureQuantities?: string[];
	transitionConfig?: TransitionConfig;
	invoiceMode?: InvoiceMode;

	// Timestamps...
	currentEpochMs: number;
	billingCycleAnchorMs: number | "now";
	resetCycleAnchorMs: number | "now";
	billingStartsAt?: number;
	subscriptionBackdateStartMs?: number;
	requestedBillingCycleAnchor?: number | "now";
	requestedProrationBehavior?: BillingBehavior;

	// Stripe context
	stripeCustomer?: Stripe.Customer;
	stripeSubscription?: Stripe.Subscription;
	stripeSubscriptionSchedule?: Stripe.SubscriptionSchedule;
	stripeDiscounts?: StripeDiscountWithCoupon[];
	stripeTaxRate?: Stripe.TaxRate;
	paymentMethod?: Stripe.PaymentMethod;

	// Unforunately, need to add custom prices, custom entitlements and free trial here, because it's determined in the setup step.
	// Optional - only needed for custom plan flows
	customPrices?: Price[];
	customEnts?: Entitlement[];

	// Trial context
	trialContext?: TrialContext;
	isCustom?: boolean;

	// Cancel action (used by update subscription for uncancel)
	cancelAction?: CancelAction;

	billingVersion: BillingVersion;
	successUrl?: string;
	checkoutSessionParams?: Record<string, unknown>;
	userMetadata?: Record<string, string>;
	taxRateId?: string;

	skipBillingChanges?: boolean;
	dryRunStripe?: boolean;

	checkoutMode?: CheckoutMode;

	// When true, the cusProduct is activated immediately even if a Stripe checkout
	// session is required. Mirrors invoice-mode enable_plan_immediately for the
	// stripe_checkout flow.
	enablePlanImmediately?: boolean;
	// When set, Autumn access starts at this time while billing may start later.
	accessStartsAt?: number;
	/** Identifies the Autumn action driving this billing context. Stamped onto Stripe
	 * subscription metadata so downstream webhook handlers can recognise Autumn-driven
	 * subscription mutations and skip auto-sync. */
	actionSource?: string;

	anchorResetRefund?: AnchorResetRefund;

	storedChargeLineItems?: DbInvoiceLineItem[];
	storedRefundLineItems?: DbInvoiceLineItem[];

	refundLastPayment?: "prorated" | "full";

	paymentBehaviorIntent?: PaymentBehaviorIntent;
	shouldFinalizeFirstInvoice?: boolean;
	skipCustomPaymentMethodGuard?: boolean;
}