import { randomUUID } from "node:crypto";
import { db } from "@kk/db";
import { adminRequest, registration, reminder } from "@kk/db/schema";
import { user } from "@kk/db/schema/auth";
import { drinkkaart, drinkkaartTopup } from "@kk/db/schema/drinkkaart";
import { env } from "@kk/env/server";
import type { RouterClient } from "@orpc/server";
import {
	and,
	count,
	desc,
	eq,
	gte,
	isNull,
	like,
	lte,
	or,
	sum,
} from "drizzle-orm";
import { z } from "zod";
import {
	sendCancellationEmail,
	sendConfirmationEmail,
	sendPaymentReminderEmail,
	sendReminderEmail,
	sendUpdateEmail,
} from "../email";
import { adminProcedure, protectedProcedure, publicProcedure } from "../index";
import { generateQrSecret } from "../lib/drinkkaart-utils";
import { drinkkaartRouter } from "./drinkkaart";

// Registration opens at this date — reminders fire 1 hour before
const REGISTRATION_OPENS_AT = new Date("2026-03-11T10:30:00+01:00");
const REMINDER_WINDOW_START = new Date(
	REGISTRATION_OPENS_AT.getTime() - 60 * 60 * 1000,
);

// ---------------------------------------------------------------------------
// Shared helpers
// ---------------------------------------------------------------------------

/** Drink card price in euros: €5 base + €2 per extra guest. */
function drinkCardEuros(guestCount: number): number {
	return 5 + guestCount * 2;
}

/** Drink card price in cents for payment processing. */
function drinkCardCents(guestCount: number): number {
	return drinkCardEuros(guestCount) * 100;
}

/** Parses the stored guest JSON blob, returning an empty array on failure. */
function parseGuestsJson(raw: string | null): Array<{
	firstName: string;
	lastName: string;
	email?: string;
	phone?: string;
}> {
	if (!raw) return [];
	try {
		const parsed = JSON.parse(raw);
		return Array.isArray(parsed) ? parsed : [];
	} catch {
		return [];
	}
}

/**
 * Credits a watcher's drinkCardValue to their drinkkaart account.
 *
 * Safe to call multiple times — the `drinkkaartCreditedAt IS NULL` guard and the
 * `mollie_payment_id` UNIQUE constraint together prevent double-crediting even
 * if called concurrently (webhook + signup racing each other).
 *
 * Returns a status string describing the outcome.
 */
export async function creditRegistrationToAccount(
	email: string,
	userId: string,
): Promise<{
	credited: boolean;
	amountCents: number;
	status:
		| "credited"
		| "already_credited"
		| "no_paid_registration"
		| "zero_value";
}> {
	// Find the most recent paid watcher registration for this email that hasn't
	// been credited yet and has a non-zero drink card value.
	const rows = await db
		.select()
		.from(registration)
		.where(
			and(
				eq(registration.email, email),
				eq(registration.registrationType, "watcher"),
				eq(registration.paymentStatus, "paid"),
				isNull(registration.cancelledAt),
				isNull(registration.drinkkaartCreditedAt),
			),
		)
		.orderBy(desc(registration.createdAt))
		.limit(1);

	const reg = rows[0];

	if (!reg) {
		// Either no paid registration exists, or it was already credited.
		// Distinguish between the two for better logging.
		const credited = await db
			.select({ id: registration.id })
			.from(registration)
			.where(
				and(
					eq(registration.email, email),
					eq(registration.registrationType, "watcher"),
					eq(registration.paymentStatus, "paid"),
					isNull(registration.cancelledAt),
				),
			)
			.limit(1)
			.then((r) => r[0]);

		return {
			credited: false,
			amountCents: 0,
			status: credited ? "already_credited" : "no_paid_registration",
		};
	}

	const drinkCardValueEuros = reg.drinkCardValue ?? 0;
	if (drinkCardValueEuros === 0) {
		return { credited: false, amountCents: 0, status: "zero_value" };
	}

	const amountCents = drinkCardValueEuros * 100;

	// Get or create the drinkkaart for this user.
	let card = await db
		.select()
		.from(drinkkaart)
		.where(eq(drinkkaart.userId, userId))
		.limit(1)
		.then((r) => r[0]);

	if (!card) {
		const now = new Date();
		card = {
			id: randomUUID(),
			userId,
			balance: 0,
			version: 0,
			qrSecret: generateQrSecret(),
			createdAt: now,
			updatedAt: now,
		};
		await db.insert(drinkkaart).values(card);
	}

	const balanceBefore = card.balance;
	const balanceAfter = balanceBefore + amountCents;

	// Optimistic-lock update — if concurrent, the second caller will see
	// drinkkaartCreditedAt IS NOT NULL and return "already_credited" above.
	const updateResult = await db
		.update(drinkkaart)
		.set({
			balance: balanceAfter,
			version: card.version + 1,
			updatedAt: new Date(),
		})
		.where(
			and(eq(drinkkaart.id, card.id), eq(drinkkaart.version, card.version)),
		);

	if (updateResult.rowsAffected === 0) {
		// Lost the optimistic lock race — the other caller will handle it.
		return { credited: false, amountCents: 0, status: "already_credited" };
	}

	// Record the topup. Re-use the registration's molliePaymentId so the
	// topup row is clearly linked to the original payment. We prefix with
	// "reg_" to distinguish from direct drinkkaart top-up orders if needed.
	const topupPaymentId = reg.molliePaymentId
		? `reg_${reg.molliePaymentId}`
		: null;

	await db.insert(drinkkaartTopup).values({
		id: randomUUID(),
		drinkkaartId: card.id,
		userId,
		amountCents,
		balanceBefore,
		balanceAfter,
		type: "payment",
		molliePaymentId: topupPaymentId,
		adminId: null,
		reason: "Drinkkaart bij registratie",
		paidAt: reg.paidAt ?? new Date(),
	});

	// Mark the registration as credited — prevents any future double-credit.
	await db
		.update(registration)
		.set({ drinkkaartCreditedAt: new Date() })
		.where(eq(registration.id, reg.id));

	return { credited: true, amountCents, status: "credited" };
}

/** Fetches a single registration by management token, throws if not found or cancelled. */
async function getActiveRegistration(token: string) {
	const rows = await db
		.select()
		.from(registration)
		.where(
			and(
				eq(registration.managementToken, token),
				isNull(registration.cancelledAt),
			),
		)
		.limit(1);
	const row = rows[0];
	if (!row) throw new Error("Inschrijving niet gevonden of al geannuleerd");
	return row;
}

// ---------------------------------------------------------------------------
// Schemas
// ---------------------------------------------------------------------------

const registrationTypeSchema = z.enum(["performer", "watcher"]);

const guestSchema = z.object({
	firstName: z.string().min(1),
	lastName: z.string().min(1),
	email: z.string().email().optional().or(z.literal("")),
	phone: z.string().optional(),
});

const coreRegistrationFields = {
	firstName: z.string().min(1),
	lastName: z.string().min(1),
	email: z.string().email(),
	phone: z.string().optional(),
	registrationType: registrationTypeSchema.default("watcher"),
	artForm: z.string().optional(),
	experience: z.string().optional(),
	isOver16: z.boolean().optional(),
	guests: z.array(guestSchema).max(9).optional(),
	extraQuestions: z.string().optional(),
	giftAmount: z.number().int().min(0).default(0),
};

const submitRegistrationSchema = z.object(coreRegistrationFields);

const updateRegistrationSchema = z.object({
	token: z.string().uuid(),
	...coreRegistrationFields,
});

const getRegistrationsSchema = z.object({
	search: z.string().optional(),
	registrationType: registrationTypeSchema.optional(),
	artForm: z.string().optional(),
	fromDate: z.string().datetime().optional(),
	toDate: z.string().datetime().optional(),
	page: z.number().int().min(1).default(1),
	pageSize: z.number().int().min(1).max(100).default(50),
});

// ---------------------------------------------------------------------------
// Router
// ---------------------------------------------------------------------------

export const appRouter = {
	healthCheck: publicProcedure.handler(() => "OK"),
	drinkkaart: drinkkaartRouter,

	privateData: protectedProcedure.handler(({ context }) => ({
		message: "This is private",
		user: context.session?.user,
	})),

	submitRegistration: publicProcedure
		.input(submitRegistrationSchema)
		.handler(async ({ input }) => {
			const managementToken = randomUUID();
			const isPerformer = input.registrationType === "performer";
			const guests = isPerformer ? [] : (input.guests ?? []);

			await db.insert(registration).values({
				id: randomUUID(),
				firstName: input.firstName,
				lastName: input.lastName,
				email: input.email,
				phone: input.phone || null,
				registrationType: input.registrationType,
				artForm: isPerformer ? input.artForm || null : null,
				experience: isPerformer ? input.experience || null : null,
				isOver16: isPerformer ? (input.isOver16 ?? false) : false,
				drinkCardValue: isPerformer ? 0 : drinkCardEuros(guests.length),
				guests: guests.length > 0 ? JSON.stringify(guests) : null,
				extraQuestions: input.extraQuestions || null,
				giftAmount: input.giftAmount,
				managementToken,
			});

			await sendConfirmationEmail({
				to: input.email,
				firstName: input.firstName,
				managementToken,
				wantsToPerform: isPerformer,
				artForm: input.artForm,
				giftAmount: input.giftAmount,
				drinkCardValue: isPerformer ? 0 : drinkCardEuros(guests.length),
			}).catch((err) =>
				console.error("Failed to send confirmation email:", err),
			);

			return { success: true, managementToken };
		}),

	getRegistrationByToken: publicProcedure
		.input(z.object({ token: z.string().uuid() }))
		.handler(async ({ input }) => {
			const rows = await db
				.select()
				.from(registration)
				.where(eq(registration.managementToken, input.token))
				.limit(1);

			const row = rows[0];
			if (!row) throw new Error("Inschrijving niet gevonden");
			if (row.cancelledAt) throw new Error("Deze inschrijving is geannuleerd");

			return row;
		}),

	updateRegistration: publicProcedure
		.input(updateRegistrationSchema)
		.handler(async ({ input }) => {
			const row = await getActiveRegistration(input.token);

			const isPerformer = input.registrationType === "performer";
			const guests = isPerformer ? [] : (input.guests ?? []);

			// Validate gift amount cannot be changed after payment
			const hasPaidGift =
				(row.paymentStatus === "paid" ||
					row.paymentStatus === "extra_payment_pending") &&
				(row.giftAmount ?? 0) > 0;
			if (hasPaidGift && input.giftAmount !== row.giftAmount) {
				throw new Error(
					"Gift kan niet worden aangepast na betaling. Neem contact op met de organisatie.",
				);
			}

			// Detect whether an already-paid watcher is adding extra guests so we
			// can charge them the delta instead of the full amount.
			const isPaid = row.paymentStatus === "paid";
			const oldGuestCount = isPerformer
				? 0
				: parseGuestsJson(row.guests).length;
			const newGuestCount = guests.length;
			const extraGuests =
				!isPerformer && isPaid ? newGuestCount - oldGuestCount : 0;

			// Determine the new paymentStatus and paymentAmount (delta in cents).
			// Only flag extra_payment_pending when the watcher genuinely owes more.
			const newPaymentStatus =
				isPaid && extraGuests > 0 ? "extra_payment_pending" : row.paymentStatus;
			const newPaymentAmount =
				newPaymentStatus === "extra_payment_pending"
					? extraGuests * 2 * 100 // €2 per extra guest, in cents
					: row.paymentAmount;

			await db
				.update(registration)
				.set({
					firstName: input.firstName,
					lastName: input.lastName,
					email: input.email,
					phone: input.phone || null,
					registrationType: input.registrationType,
					artForm: isPerformer ? input.artForm || null : null,
					experience: isPerformer ? input.experience || null : null,
					isOver16: isPerformer ? (input.isOver16 ?? false) : false,
					drinkCardValue: isPerformer ? 0 : drinkCardEuros(guests.length),
					guests: guests.length > 0 ? JSON.stringify(guests) : null,
					extraQuestions: input.extraQuestions || null,
					giftAmount: input.giftAmount,
					paymentStatus: newPaymentStatus,
					paymentAmount: newPaymentAmount,
				})
				.where(eq(registration.managementToken, input.token));

			await sendUpdateEmail({
				to: input.email,
				firstName: input.firstName,
				managementToken: input.token,
				wantsToPerform: isPerformer,
				artForm: input.artForm,
				giftAmount: input.giftAmount,
				drinkCardValue: isPerformer ? 0 : drinkCardEuros(guests.length),
			}).catch((err) => console.error("Failed to send update email:", err));

			return { success: true };
		}),

	cancelRegistration: publicProcedure
		.input(z.object({ token: z.string().uuid() }))
		.handler(async ({ input }) => {
			const row = await getActiveRegistration(input.token);

			await db
				.update(registration)
				.set({ cancelledAt: new Date() })
				.where(eq(registration.managementToken, input.token));

			await sendCancellationEmail({
				to: row.email,
				firstName: row.firstName,
			}).catch((err) =>
				console.error("Failed to send cancellation email:", err),
			);

			return { success: true };
		}),

	getRegistrations: adminProcedure
		.input(getRegistrationsSchema)
		.handler(async ({ input }) => {
			const conditions = [];

			if (input.search) {
				const term = `%${input.search}%`;
				conditions.push(
					or(
						like(registration.firstName, term),
						like(registration.lastName, term),
						like(registration.email, term),
					),
				);
			}
			if (input.registrationType)
				conditions.push(
					eq(registration.registrationType, input.registrationType),
				);
			if (input.artForm)
				conditions.push(eq(registration.artForm, input.artForm));
			if (input.fromDate)
				conditions.push(gte(registration.createdAt, new Date(input.fromDate)));
			if (input.toDate)
				conditions.push(lte(registration.createdAt, new Date(input.toDate)));

			const where = conditions.length > 0 ? and(...conditions) : undefined;

			const [data, countResult] = await Promise.all([
				db
					.select()
					.from(registration)
					.where(where)
					.orderBy(desc(registration.createdAt))
					.limit(input.pageSize)
					.offset((input.page - 1) * input.pageSize),
				db.select({ count: count() }).from(registration).where(where),
			]);

			const total = countResult[0]?.count ?? 0;

			return {
				data,
				pagination: {
					page: input.page,
					pageSize: input.pageSize,
					total,
					totalPages: Math.ceil(total / input.pageSize),
				},
			};
		}),

	getRegistrationStats: adminProcedure.handler(async () => {
		const today = new Date();
		today.setHours(0, 0, 0, 0);

		const [
			totalResult,
			todayResult,
			artFormResult,
			typeResult,
			giftResult,
			watcherGuestRows,
		] = await Promise.all([
			db.select({ count: count() }).from(registration),
			db
				.select({ count: count() })
				.from(registration)
				.where(gte(registration.createdAt, today)),
			db
				.select({ artForm: registration.artForm, count: count() })
				.from(registration)
				.where(eq(registration.registrationType, "performer"))
				.groupBy(registration.artForm),
			db
				.select({
					registrationType: registration.registrationType,
					count: count(),
				})
				.from(registration)
				.groupBy(registration.registrationType),
			db.select({ total: sum(registration.giftAmount) }).from(registration),
			// Fetch guests column for all watcher registrations to count total guests
			db
				.select({ guests: registration.guests })
				.from(registration)
				.where(
					and(
						eq(registration.registrationType, "watcher"),
						isNull(registration.cancelledAt),
					),
				),
		]);

		// Sum up all guest counts across all watcher registrations
		const totalGuestCount = watcherGuestRows.reduce((sum, r) => {
			const guests = parseGuestsJson(r.guests);
			return sum + guests.length;
		}, 0);

		return {
			total: totalResult[0]?.count ?? 0,
			today: todayResult[0]?.count ?? 0,
			byArtForm: artFormResult.map((r) => ({
				artForm: r.artForm,
				count: r.count,
			})),
			byType: typeResult.map((r) => ({
				registrationType: r.registrationType,
				count: r.count,
			})),
			totalGiftRevenue: giftResult[0]?.total ?? 0,
			totalGuestCount,
		};
	}),

	exportRegistrations: adminProcedure.handler(async () => {
		const data = await db
			.select()
			.from(registration)
			.orderBy(desc(registration.createdAt));

		const escapeCell = (val: string) => `"${val.replace(/"/g, '""')}"`;

		// Main registration headers
		const headers = [
			"ID",
			"First Name",
			"Last Name",
			"Email",
			"Phone",
			"Type",
			"Art Form",
			"Experience",
			"Is Over 16",
			"Drink Card Value (EUR)",
			"Gift Amount (cents)",
			"Guest Count",
			"Guest 1 First Name",
			"Guest 1 Last Name",
			"Guest 1 Email",
			"Guest 1 Phone",
			"Guest 2 First Name",
			"Guest 2 Last Name",
			"Guest 2 Email",
			"Guest 2 Phone",
			"Guest 3 First Name",
			"Guest 3 Last Name",
			"Guest 3 Email",
			"Guest 3 Phone",
			"Guest 4 First Name",
			"Guest 4 Last Name",
			"Guest 4 Email",
			"Guest 4 Phone",
			"Guest 5 First Name",
			"Guest 5 Last Name",
			"Guest 5 Email",
			"Guest 5 Phone",
			"Guest 6 First Name",
			"Guest 6 Last Name",
			"Guest 6 Email",
			"Guest 6 Phone",
			"Guest 7 First Name",
			"Guest 7 Last Name",
			"Guest 7 Email",
			"Guest 7 Phone",
			"Guest 8 First Name",
			"Guest 8 Last Name",
			"Guest 8 Email",
			"Guest 8 Phone",
			"Guest 9 First Name",
			"Guest 9 Last Name",
			"Guest 9 Email",
			"Guest 9 Phone",
			"Payment Status",
			"Paid At",
			"Extra Questions",
			"Cancelled At",
			"Created At",
		];

		const MAX_GUESTS = 9;

		const rows = data.map((r) => {
			const guests = parseGuestsJson(r.guests);

			// Build guest columns (up to 9 guests, 4 fields each)
			const guestCols: string[] = [];
			for (let i = 0; i < MAX_GUESTS; i++) {
				const g = guests[i];
				guestCols.push(g?.firstName ?? "");
				guestCols.push(g?.lastName ?? "");
				guestCols.push(g?.email ?? "");
				guestCols.push(g?.phone ?? "");
			}

			return [
				r.id,
				r.firstName,
				r.lastName,
				r.email,
				r.phone || "",
				r.registrationType ?? "",
				r.artForm || "",
				r.experience || "",
				r.isOver16 ? "Yes" : "No",
				String(r.drinkCardValue ?? 0),
				String(r.giftAmount ?? 0),
				String(guests.length),
				...guestCols,
				r.paymentStatus === "paid"
					? "Paid"
					: r.paymentStatus === "extra_payment_pending"
						? "Extra Payment Pending"
						: "Pending",
				r.paidAt ? r.paidAt.toISOString() : "",
				r.extraQuestions || "",
				r.cancelledAt ? r.cancelledAt.toISOString() : "",
				r.createdAt.toISOString(),
			];
		});

		const csvContent = [
			headers.map(escapeCell).join(","),
			...rows.map((row) =>
				row.map((cell) => escapeCell(String(cell))).join(","),
			),
		].join("\n");

		return {
			csv: csvContent,
			filename: `registrations-${new Date().toISOString().split("T")[0]}.csv`,
		};
	}),

	// ---------------------------------------------------------------------------
	// User account
	// ---------------------------------------------------------------------------

	claimRegistrationCredit: protectedProcedure.handler(async ({ context }) => {
		const result = await creditRegistrationToAccount(
			context.session.user.email,
			context.session.user.id,
		);
		return result;
	}),

	getMyRegistration: protectedProcedure.handler(async ({ context }) => {
		const email = context.session.user.email;

		const rows = await db
			.select()
			.from(registration)
			.where(
				and(eq(registration.email, email), isNull(registration.cancelledAt)),
			)
			.orderBy(desc(registration.createdAt))
			.limit(1);

		const row = rows[0];
		if (!row) return null;

		return {
			...row,
			guests: parseGuestsJson(row.guests),
		};
	}),

	// ---------------------------------------------------------------------------
	// Admin access requests
	// ---------------------------------------------------------------------------

	requestAdminAccess: protectedProcedure.handler(async ({ context }) => {
		const userId = context.session.user.id;

		if (context.session.user.role === "admin") {
			return { success: false, message: "Je bent al een admin" };
		}

		const existing = await db
			.select()
			.from(adminRequest)
			.where(eq(adminRequest.userId, userId))
			.limit(1)
			.then((rows) => rows[0]);

		if (existing) {
			if (existing.status === "pending")
				return {
					success: false,
					message: "Je hebt al een aanvraag openstaan",
				};
			if (existing.status === "approved")
				return {
					success: false,
					message: "Je aanvraag is al goedgekeurd, log opnieuw in",
				};
			// Rejected — allow re-request
			await db
				.update(adminRequest)
				.set({
					status: "pending",
					requestedAt: new Date(),
					reviewedAt: null,
					reviewedBy: null,
				})
				.where(eq(adminRequest.userId, userId));
			return { success: true, message: "Nieuwe aanvraag ingediend" };
		}

		await db.insert(adminRequest).values({
			id: randomUUID(),
			userId,
			status: "pending",
		});

		return { success: true, message: "Admin toegang aangevraagd" };
	}),

	getAdminRequests: adminProcedure.handler(async () => {
		return db
			.select({
				id: adminRequest.id,
				userId: adminRequest.userId,
				status: adminRequest.status,
				requestedAt: adminRequest.requestedAt,
				reviewedAt: adminRequest.reviewedAt,
				reviewedBy: adminRequest.reviewedBy,
				userName: user.name,
				userEmail: user.email,
			})
			.from(adminRequest)
			.leftJoin(user, eq(adminRequest.userId, user.id))
			.orderBy(desc(adminRequest.requestedAt));
	}),

	approveAdminRequest: adminProcedure
		.input(z.object({ requestId: z.string() }))
		.handler(async ({ input, context }) => {
			const req = await db
				.select()
				.from(adminRequest)
				.where(eq(adminRequest.id, input.requestId))
				.limit(1)
				.then((rows) => rows[0]);

			if (!req) throw new Error("Aanvraag niet gevonden");
			if (req.status !== "pending")
				throw new Error("Deze aanvraag is al behandeld");

			await db
				.update(adminRequest)
				.set({
					status: "approved",
					reviewedAt: new Date(),
					reviewedBy: context.session.user.id,
				})
				.where(eq(adminRequest.id, input.requestId));

			await db
				.update(user)
				.set({ role: "admin" })
				.where(eq(user.id, req.userId));

			return { success: true, message: "Admin toegang goedgekeurd" };
		}),

	rejectAdminRequest: adminProcedure
		.input(z.object({ requestId: z.string() }))
		.handler(async ({ input, context }) => {
			const req = await db
				.select()
				.from(adminRequest)
				.where(eq(adminRequest.id, input.requestId))
				.limit(1)
				.then((rows) => rows[0]);

			if (!req) throw new Error("Aanvraag niet gevonden");
			if (req.status !== "pending")
				throw new Error("Deze aanvraag is al behandeld");

			await db
				.update(adminRequest)
				.set({
					status: "rejected",
					reviewedAt: new Date(),
					reviewedBy: context.session.user.id,
				})
				.where(eq(adminRequest.id, input.requestId));

			return { success: true, message: "Admin toegang geweigerd" };
		}),

	// ---------------------------------------------------------------------------
	// Reminder opt-in
	// ---------------------------------------------------------------------------

	/**
	 * Subscribe an email address to receive a reminder 1 hour before registration
	 * opens. Silently deduplicates — if the email is already subscribed, returns
	 * ok:true without error. Returns ok:false if registration is already open.
	 */
	subscribeReminder: publicProcedure
		.input(z.object({ email: z.string().email() }))
		.handler(async ({ input }) => {
			const now = Date.now();

			// Registration is already open — no point subscribing
			if (now >= REGISTRATION_OPENS_AT.getTime()) {
				return { ok: false, reason: "already_open" as const };
			}

			// Check for an existing subscription (silent dedup)
			const existing = await db
				.select({ id: reminder.id })
				.from(reminder)
				.where(eq(reminder.email, input.email))
				.limit(1)
				.then((rows) => rows[0]);

			if (existing) {
				return { ok: true };
			}

			await db.insert(reminder).values({
				id: randomUUID(),
				email: input.email,
			});

			return { ok: true };
		}),

	/**
	 * Send pending reminder emails to all opted-in addresses.
	 * Protected by a shared secret (`CRON_SECRET`) passed as an Authorization
	 * header. Should be called by a Cloudflare Cron Trigger at the top of
	 * every hour, or directly via `POST /api/cron/reminders`.
	 *
	 * Only sends when the current time is within the 1-hour reminder window
	 * (between REGISTRATION_OPENS_AT - 1h and REGISTRATION_OPENS_AT).
	 */
	sendReminders: publicProcedure
		.input(z.object({ secret: z.string() }))
		.handler(async ({ input }) => {
			// Validate the shared secret
			if (!env.CRON_SECRET || input.secret !== env.CRON_SECRET) {
				throw new Error("Unauthorized");
			}

			const now = Date.now();
			const windowStart = REMINDER_WINDOW_START.getTime();
			const windowEnd = REGISTRATION_OPENS_AT.getTime();

			// Only send during the reminder window
			if (now < windowStart || now >= windowEnd) {
				return { sent: 0, skipped: true, reason: "outside_window" as const };
			}

			// Fetch all unsent reminders
			const pending = await db
				.select()
				.from(reminder)
				.where(isNull(reminder.sentAt));

			let sent = 0;
			const errors: string[] = [];

			for (const row of pending) {
				try {
					await sendReminderEmail({ to: row.email });
					await db
						.update(reminder)
						.set({ sentAt: new Date() })
						.where(eq(reminder.id, row.id));
					sent++;
				} catch (err) {
					errors.push(`${row.email}: ${String(err)}`);
					console.error(`Failed to send reminder to ${row.email}:`, err);
				}
			}

			return { sent, skipped: false, errors };
		}),

	// ---------------------------------------------------------------------------
	// Checkout
	// ---------------------------------------------------------------------------

	getCheckoutUrl: publicProcedure
		.input(
			z.object({
				token: z.string().uuid(),
				redirectUrl: z.string().optional(),
			}),
		)
		.handler(async ({ input }) => {
			if (!env.MOLLIE_API_KEY) {
				throw new Error("Mollie is niet geconfigureerd");
			}

			const rows = await db
				.select()
				.from(registration)
				.where(
					and(
						eq(registration.managementToken, input.token),
						isNull(registration.cancelledAt),
					),
				)
				.limit(1);

			const row = rows[0];
			if (!row) throw new Error("Inschrijving niet gevonden");
			if (row.paymentStatus === "paid")
				throw new Error("Betaling is al voltooid");
			if (
				row.paymentStatus !== "pending" &&
				row.paymentStatus !== "extra_payment_pending"
			)
				throw new Error("Onverwachte betalingsstatus");

			const isPerformer = row.registrationType === "performer";
			const guests = parseGuestsJson(row.guests);
			const giftTotal = row.giftAmount ?? 0;

			// Performers only pay if they have a gift; watchers pay drink card + gift
			if (isPerformer && giftTotal === 0) {
				throw new Error("Artiesten hoeven niet te betalen");
			}

			// For an extra_payment_pending registration, charge only the delta
			// (stored in paymentAmount in cents). For a fresh pending registration
			// charge the full drink card price. Always add any gift amount.
			const isExtraPayment = row.paymentStatus === "extra_payment_pending";
			const drinkCardTotal = isExtraPayment
				? (row.paymentAmount ?? 0)
				: isPerformer
					? 0
					: drinkCardCents(guests.length);
			const amountInCents = drinkCardTotal + giftTotal;

			const productDescription = isExtraPayment
				? `Extra bijdrage${giftTotal > 0 ? " + gift" : ""}`
				: isPerformer
					? `Vrijwillige gift${drinkCardTotal > 0 ? " + drinkkaart" : ""}`
					: `Toegangskaart${giftTotal > 0 ? " + gift" : ""}`;

			const redirectUrl =
				input.redirectUrl ?? `${env.CORS_ORIGIN}/manage/${input.token}`;

			// Mollie amounts must be formatted as "10.00" (string, 2 decimal places)
			const amountValue = (amountInCents / 100).toFixed(2);

			const webhookUrl = `${env.CORS_ORIGIN}/api/webhook/mollie`;

			const response = await fetch("https://api.mollie.com/v2/payments", {
				method: "POST",
				headers: {
					"Content-Type": "application/json",
					Authorization: `Bearer ${env.MOLLIE_API_KEY}`,
				},
				body: JSON.stringify({
					amount: { value: amountValue, currency: "EUR" },
					description: `Kunstenkamp Evenement — ${productDescription}`,
					redirectUrl,
					webhookUrl,
					locale: "nl_NL",
					metadata: { registration_token: input.token },
				}),
			});

			if (!response.ok) {
				const errorData = await response.json();
				console.error("Mollie checkout error:", errorData);
				throw new Error("Kon checkout niet aanmaken");
			}

			const checkoutData = (await response.json()) as {
				_links?: { checkout?: { href?: string } };
			};
			const checkoutUrl = checkoutData._links?.checkout?.href;

			if (!checkoutUrl) throw new Error("Geen checkout URL ontvangen");

			return { checkoutUrl };
		}),
};

export type AppRouter = typeof appRouter;
export type AppRouterClient = RouterClient<typeof appRouter>;

/**
 * Standalone function that sends pending reminder emails.
 * Exported so that the Cloudflare Cron HTTP handler can call it directly
 * without needing drizzle-orm as a direct dependency of apps/web.
 */
export async function runSendReminders(): Promise<{
	sent: number;
	skipped: boolean;
	reason?: string;
	errors: string[];
}> {
	const now = Date.now();
	const windowStart = REMINDER_WINDOW_START.getTime();
	const windowEnd = REGISTRATION_OPENS_AT.getTime();

	if (now < windowStart || now >= windowEnd) {
		return { sent: 0, skipped: true, reason: "outside_window", errors: [] };
	}

	const pending = await db
		.select()
		.from(reminder)
		.where(isNull(reminder.sentAt));

	let sent = 0;
	const errors: string[] = [];

	for (const row of pending) {
		try {
			await sendReminderEmail({ to: row.email });
			await db
				.update(reminder)
				.set({ sentAt: new Date() })
				.where(eq(reminder.id, row.id));
			sent++;
		} catch (err) {
			errors.push(`${row.email}: ${String(err)}`);
			console.error(`Failed to send reminder to ${row.email}:`, err);
		}
	}

	// Payment reminders: watchers with pending payment older than 3 days
	const threeDaysAgo = now - 3 * 24 * 60 * 60 * 1000;
	const unpaidWatchers = await db
		.select()
		.from(registration)
		.where(
			and(
				eq(registration.registrationType, "watcher"),
				eq(registration.paymentStatus, "pending"),
				isNull(registration.paymentReminderSentAt),
				lte(registration.createdAt, new Date(threeDaysAgo)),
			),
		);

	for (const reg of unpaidWatchers) {
		if (!reg.managementToken) continue;
		try {
			await sendPaymentReminderEmail({
				to: reg.email,
				firstName: reg.firstName,
				managementToken: reg.managementToken,
				drinkCardValue: reg.drinkCardValue ?? undefined,
				giftAmount: reg.giftAmount ?? undefined,
			});
			await db
				.update(registration)
				.set({ paymentReminderSentAt: new Date() })
				.where(eq(registration.id, reg.id));
			sent++;
		} catch (err) {
			errors.push(`payment-reminder ${reg.email}: ${String(err)}`);
			console.error(`Failed to send payment reminder to ${reg.email}:`, err);
		}
	}

	return { sent, skipped: false, errors };
}