import { z } from "zod";
import { MessageHandler } from "../ws";
import logger from "@server/logger";
import { fromError } from "zod-validation-error";
import {
    db,
    ExitNode,
    exitNodes,
    resources,
    Target,
    targets
} from "@server/db";
import { clients, clientSites, Newt, sites } from "@server/db";
import { eq, and, inArray } from "drizzle-orm";
import { updatePeer } from "../olm/peers";
import axios from "axios";

const inputSchema = z.object({
    publicKey: z.string(),
    port: z.number().int().positive()
});

type Input = z.infer<typeof inputSchema>;

export const handleGetConfigMessage: MessageHandler = async (context) => {
    const { message, client, sendToClient } = context;
    const newt = client as Newt;

    const now = new Date().getTime() / 1000;

    logger.debug("Handling Newt get config message!");

    if (!newt) {
        logger.warn("Newt not found");
        return;
    }

    if (!newt.siteId) {
        logger.warn("Newt has no site!"); // TODO: Maybe we create the site here?
        return;
    }

    const parsed = inputSchema.safeParse(message.data);
    if (!parsed.success) {
        logger.error(
            "handleGetConfigMessage: Invalid input: " +
                fromError(parsed.error).toString()
        );
        return;
    }

    const { publicKey, port } = message.data as Input;
    const siteId = newt.siteId;

    // Get the current site data
    const [existingSite] = await db
        .select()
        .from(sites)
        .where(eq(sites.siteId, siteId));

    if (!existingSite) {
        logger.warn("handleGetConfigMessage: Site not found");
        return;
    }

    // we need to wait for hole punch success
    if (!existingSite.endpoint) {
        logger.warn(`Site ${existingSite.siteId} has no endpoint, skipping`);
        return;
    }

    if (existingSite.publicKey !== publicKey) {
        // TODO: somehow we should make sure a recent hole punch has happened if this occurs (hole punch could be from the last restart if done quickly)
    }

    if (existingSite.lastHolePunch && now - existingSite.lastHolePunch > 6) {
        logger.warn(
            `Site ${existingSite.siteId} last hole punch is too old, skipping`
        );
        return;
    }

    // update the endpoint and the public key
    const [site] = await db
        .update(sites)
        .set({
            publicKey,
            listenPort: port
        })
        .where(eq(sites.siteId, siteId))
        .returning();

    if (!site) {
        logger.error("handleGetConfigMessage: Failed to update site");
        return;
    }

    let exitNode: ExitNode | undefined;
    if (site.exitNodeId) {
        [exitNode] = await db
            .select()
            .from(exitNodes)
            .where(eq(exitNodes.exitNodeId, site.exitNodeId))
            .limit(1);
        if (exitNode.reachableAt) {
            try {
                const response = await axios.post(
                    `${exitNode.reachableAt}/update-proxy-mapping`,
                    {
                        oldDestination: {
                            destinationIP: existingSite.subnet?.split("/")[0],
                            destinationPort: existingSite.listenPort
                        },
                        newDestination: {
                            destinationIP: site.subnet?.split("/")[0],
                            destinationPort: site.listenPort
                        }
                    },
                    {
                        headers: {
                            "Content-Type": "application/json"
                        }
                    }
                );

                logger.info("Destinations updated:", {
                    peer: response.data.status
                });
            } catch (error) {
                if (axios.isAxiosError(error)) {
                    throw new Error(
                        `Error communicating with Gerbil. Make sure Pangolin can reach the Gerbil HTTP API: ${error.response?.status}`
                    );
                }
                throw error;
            }
        }
    }

    // Get all clients connected to this site
    const clientsRes = await db
        .select()
        .from(clients)
        .innerJoin(clientSites, eq(clients.clientId, clientSites.clientId))
        .where(eq(clientSites.siteId, siteId));

    // Prepare peers data for the response
    const peers = await Promise.all(
        clientsRes
            .filter((client) => {
                if (!client.clients.pubKey) {
                    return false;
                }
                if (!client.clients.subnet) {
                    return false;
                }
                if (!client.clients.endpoint) {
                    return false;
                }
                return true;
            })
            .map(async (client) => {
                // Add or update this peer on the olm if it is connected
                try {
                    if (!site.publicKey) {
                        logger.warn(
                            `Site ${site.siteId} has no public key, skipping`
                        );
                        return null;
                    }
                    let endpoint = site.endpoint;
                    if (client.clientSites.isRelayed) {
                        if (!site.exitNodeId) {
                            logger.warn(
                                `Site ${site.siteId} has no exit node, skipping`
                            );
                            return null;
                        }

                        if (!exitNode) {
                            logger.warn(
                                `Exit node not found for site ${site.siteId}`
                            );
                            return null;
                        }
                        endpoint = `${exitNode.endpoint}:21820`;
                    }

                    if (!endpoint) {
                        logger.warn(
                            `Site ${site.siteId} has no endpoint, skipping`
                        );
                        return null;
                    }

                    await updatePeer(client.clients.clientId, {
                        siteId: site.siteId,
                        endpoint: endpoint,
                        publicKey: site.publicKey,
                        serverIP: site.address,
                        serverPort: site.listenPort,
                        remoteSubnets: site.remoteSubnets
                    });
                } catch (error) {
                    logger.error(
                        `Failed to add/update peer ${client.clients.pubKey} to olm ${newt.newtId}: ${error}`
                    );
                }

                return {
                    publicKey: client.clients.pubKey!,
                    allowedIps: [`${client.clients.subnet.split("/")[0]}/32`], // we want to only allow from that client
                    endpoint: client.clientSites.isRelayed
                        ? ""
                        : client.clients.endpoint! // if its relayed it should be localhost
                };
            })
    );

    // Filter out any null values from peers that didn't have an olm
    const validPeers = peers.filter((peer) => peer !== null);

    // Improved version
    const allResources = await db.transaction(async (tx) => {
        // First get all resources for the site
        const resourcesList = await tx
            .select({
                resourceId: resources.resourceId,
                subdomain: resources.subdomain,
                fullDomain: resources.fullDomain,
                ssl: resources.ssl,
                blockAccess: resources.blockAccess,
                sso: resources.sso,
                emailWhitelistEnabled: resources.emailWhitelistEnabled,
                http: resources.http,
                proxyPort: resources.proxyPort,
                protocol: resources.protocol
            })
            .from(resources)
            .where(and(eq(resources.siteId, siteId), eq(resources.http, false)));

        // Get all enabled targets for these resources in a single query
        const resourceIds = resourcesList.map((r) => r.resourceId);
        const allTargets =
            resourceIds.length > 0
                ? await tx
                      .select({
                          resourceId: targets.resourceId,
                          targetId: targets.targetId,
                          ip: targets.ip,
                          method: targets.method,
                          port: targets.port,
                          internalPort: targets.internalPort,
                          enabled: targets.enabled,
                      })
                      .from(targets)
                      .where(
                          and(
                              inArray(targets.resourceId, resourceIds),
                              eq(targets.enabled, true)
                          )
                      )
                : [];

        // Combine the data in JS instead of using SQL for the JSON
        return resourcesList.map((resource) => ({
            ...resource,
            targets: allTargets.filter(
                (target) => target.resourceId === resource.resourceId
            )
        }));
    });

    const { tcpTargets, udpTargets } = allResources.reduce(
        (acc, resource) => {
            // Skip resources with no targets
            if (!resource.targets?.length) return acc;

            // Format valid targets into strings
            const formattedTargets = resource.targets
                .filter(
                    (target: Target) =>
                        resource.proxyPort && target?.ip && target?.port
                )
                .map(
                    (target: Target) =>
                        `${resource.proxyPort}:${target.ip}:${target.port}`
                );

            // Add to the appropriate protocol array
            if (resource.protocol === "tcp") {
                acc.tcpTargets.push(...formattedTargets);
            } else {
                acc.udpTargets.push(...formattedTargets);
            }

            return acc;
        },
        { tcpTargets: [] as string[], udpTargets: [] as string[] }
    );

    // Build the configuration response
    const configResponse = {
        ipAddress: site.address,
        peers: validPeers,
        targets: {
            udp: udpTargets,
            tcp: tcpTargets
        }
    };

    logger.debug("Sending config: ", configResponse);
    return {
        message: {
            type: "newt/wg/receive-config",
            data: {
                ...configResponse
            }
        },
        broadcast: false,
        excludeSender: false
    };
};