import pMap from "p-map";
import { Mailer } from "../lib/Mailer";
import { logger } from "../utils/logger";
import { prisma } from "../utils/prisma";

import { cronJob } from "./cron.utils";
import { subSeconds } from "date-fns";

export const sendMessagesCron = cronJob("sendMessages", async () => {
	const organizations = await prisma.organization.findMany();

	for (const organization of organizations) {
		const [smtpSettings, emailSettings, generalSettings] = await Promise.all([
			prisma.smtpSettings.findFirst({
				where: { organizationId: organization.id },
			}),
			prisma.emailDeliverySettings.findFirst({
				where: { organizationId: organization.id },
			}),
			prisma.generalSettings.findFirst({
				where: { organizationId: organization.id },
			}),
		]);

		if (!smtpSettings || !emailSettings) {
			logger.warn(
				`Required settings not found for org ${organization.id}, skipping`,
			);
			continue;
		}

		const windowStart = subSeconds(new Date(), emailSettings.rateWindow);
		const sentInWindow = await prisma.message.count({
			where: {
				status: {
					in: ["PENDING", "SENT", "OPENED", "CLICKED"],
				},
				sentAt: {
					gte: windowStart,
				},
				Campaign: {
					organizationId: organization.id,
				},
			},
		});

		const availableSlots = Math.max(0, emailSettings.rateLimit - sentInWindow);

		if (availableSlots === 0) {
			continue;
		}

		// Message status is now independent of campaign status.
		// This allows retrying individual messages even for completed campaigns.
		// We only filter by QUEUED and RETRYING message statuses.
		const messages = await prisma.message.findMany({
			where: {
				Campaign: {
					organizationId: organization.id,
				},
				OR: [
					{ status: "QUEUED" },
					{
						status: "RETRYING",
						lastTriedAt: {
							lte: subSeconds(new Date(), emailSettings.retryDelay),
						},
					},
				],
			},
			include: {
				Subscriber: {
					select: {
						email: true,
					},
				},
				Campaign: {
					select: {
						subject: true,
					},
				},
			},
			take: availableSlots,
		});

		const noMoreRetryingMessages = await prisma.message.count({
			where: {
				status: "RETRYING",
				Campaign: {
					organizationId: organization.id,
				},
			},
		});

		if (!messages.length && noMoreRetryingMessages === 0) {
			await prisma.campaign.updateMany({
				where: {
					status: "SENDING",
					organizationId: organization.id,
					Messages: {
						every: {
							status: {
								in: ["SENT", "FAILED", "OPENED", "CLICKED", "CANCELLED"],
							},
						},
					},
				},
				data: {
					status: "COMPLETED",
					completedAt: new Date(),
				},
			});
			continue;
		}

		logger.info(`Found ${messages.length} messages to send`);

		const mailer = new Mailer({
			...smtpSettings,
			timeout: emailSettings.connectionTimeout,
		});

		const fromName =
			smtpSettings.fromName ?? generalSettings?.defaultFromName ?? "";
		const fromEmail =
			smtpSettings.fromEmail ?? generalSettings?.defaultFromEmail ?? "";

		if (!fromName || !fromEmail) {
			logger.warn("No from name or email found, message will not be sent");
			continue;
		}

		await pMap(
			messages,
			async (message) => {
				if (!message.Campaign.subject) {
					logger.warn("No subject found for campaign");
					return;
				}

				await prisma.message.update({
					where: { id: message.id },
					data: { status: "PENDING" },
				});

				try {
					const result = await mailer.sendEmail({
						to: message.Subscriber.email,
						subject: message.Campaign.subject,
						html: message.content,
						from: `${fromName} <${fromEmail}>`,
					});

					await prisma.message.update({
						where: { id: message.id },
						data: {
							messageId: result.messageId,
							status: result.success
								? "SENT"
								: message.tries >= emailSettings.maxRetries
									? "FAILED"
									: "RETRYING",
							sentAt: result.success ? new Date() : undefined,
							tries: {
								increment: 1,
							},
							lastTriedAt: new Date(),
						},
					});
				} catch (error) {
					await prisma.message.update({
						where: { id: message.id },
						data: {
							status:
								message.tries >= emailSettings.maxRetries
									? "FAILED"
									: "RETRYING",
							error: String(error),
							tries: {
								increment: 1,
							},
							lastTriedAt: new Date(),
						},
					});
				}
			},
			{ concurrency: emailSettings.concurrency },
		);
	}
});