import { FastifyInstance } from "fastify"
import axios from "axios"
import dayjs from "dayjs"

import { secrets } from "../utils/secrets"
import { insertHistoryItem } from "../utils/history"

import {
    bankrequisitions,
    statementallocations,
} from "../../db/schema"

import {
    eq,
    and,
} from "drizzle-orm"


export default async function bankingRoutes(server: FastifyInstance) {

    // ------------------------------------------------------------------
    // 🔐 GoCardLess Token Handling
    // ------------------------------------------------------------------

    const goCardLessBaseUrl = secrets.GOCARDLESS_BASE_URL
    const goCardLessSecretId = secrets.GOCARDLESS_SECRET_ID
    const goCardLessSecretKey = secrets.GOCARDLESS_SECRET_KEY

    let tokenData: any = null

    const getToken = async () => {
        const res = await axios.post(`${goCardLessBaseUrl}/token/new/`, {
            secret_id: goCardLessSecretId,
            secret_key: goCardLessSecretKey,
        })

        tokenData = res.data
        tokenData.created_at = new Date().toISOString()

        server.log.info("GoCardless token refreshed.")
    }

    const checkToken = async () => {
        if (!tokenData) return await getToken()

        const expired = dayjs(tokenData.created_at)
            .add(tokenData.access_expires, "seconds")
            .isBefore(dayjs())

        if (expired) {
            server.log.info("Refreshing expired GoCardless token …")
            await getToken()
        }
    }

    // ------------------------------------------------------------------
    // 🔗 Create GoCardless Banking Link
    // ------------------------------------------------------------------
    server.get("/banking/link/:institutionid", async (req, reply) => {
        try {
            await checkToken()

            const { institutionid } = req.params as { institutionid: string }
            const tenantId = req.user?.tenant_id

            if (!tenantId) return reply.code(401).send({ error: "Unauthorized" })

            const { data } = await axios.post(
                `${goCardLessBaseUrl}/requisitions/`,
                {
                    redirect: "https://app.fedeo.de/settings/banking",
                    institution_id: institutionid,
                    user_language: "de",
                },
                {
                    headers: { Authorization: `Bearer ${tokenData.access}` },
                }
            )

            // DB: Requisition speichern
            await server.db.insert(bankrequisitions).values({
                id: data.id,
                tenant: tenantId,
                institutionId: institutionid,
                status: data.status,
            })

            return reply.send({ link: data.link })
        } catch (err: any) {
            server.log.error(err?.response?.data || err)
            return reply.code(500).send({ error: "Failed to generate link" })
        }
    })

    // ------------------------------------------------------------------
    // 🏦 Check Bank Institutions
    // ------------------------------------------------------------------
    server.get("/banking/institutions/:bic", async (req, reply) => {
        try {
            const { bic } = req.params as { bic: string }
            if (!bic) return reply.code(400).send("BIC missing")

            await checkToken()

            const { data } = await axios.get(
                `${goCardLessBaseUrl}/institutions/?country=de`,
                { headers: { Authorization: `Bearer ${tokenData.access}` } }
            )

            const bank = data.find((i: any) => i.bic.toLowerCase() === bic.toLowerCase())

            if (!bank) return reply.code(404).send("Bank not found")

            return reply.send(bank)
        } catch (err: any) {
            server.log.error(err?.response?.data || err)
            return reply.code(500).send("Failed to fetch institutions")
        }
    })


    // ------------------------------------------------------------------
    // 📄 Get Requisition Details
    // ------------------------------------------------------------------
    server.get("/banking/requisitions/:reqId", async (req, reply) => {
        try {
            const { reqId } = req.params as { reqId: string }
            if (!reqId) return reply.code(400).send("Requisition ID missing")

            await checkToken()

            const { data } = await axios.get(
                `${goCardLessBaseUrl}/requisitions/${reqId}`,
                { headers: { Authorization: `Bearer ${tokenData.access}` } }
            )

            // Load account details
            if (data.accounts) {
                data.accounts = await Promise.all(
                    data.accounts.map(async (accId: string) => {
                        const { data: acc } = await axios.get(
                            `${goCardLessBaseUrl}/accounts/${accId}`,
                            { headers: { Authorization: `Bearer ${tokenData.access}` } }
                        )
                        return acc
                    })
                )
            }

            return reply.send(data)
        } catch (err: any) {
            server.log.error(err?.response?.data || err)
            return reply.code(500).send("Failed to fetch requisition details")
        }
    })


    // ------------------------------------------------------------------
    // 💰 Create Statement Allocation
    // ------------------------------------------------------------------
    server.post("/banking/statements", async (req, reply) => {
        try {
            if (!req.user) return reply.code(401).send({ error: "Unauthorized" })

            const { data: payload } = req.body as { data: any }

            const inserted = await server.db.insert(statementallocations).values({
                ...payload,
                tenant: req.user.tenant_id
            }).returning()

            const createdRecord = inserted[0]

            await insertHistoryItem(server, {
                entity: "bankstatements",
                entityId: createdRecord.id,
                action: "created",
                created_by: req.user.user_id,
                tenant_id: req.user.tenant_id,
                oldVal: null,
                newVal: createdRecord,
                text: "Buchung erstellt",
            })

            return reply.send(createdRecord)

        } catch (err) {
            console.error(err)
            return reply.code(500).send({ error: "Failed to create statement" })
        }
    })


    // ------------------------------------------------------------------
    // 🗑 Delete Statement Allocation
    // ------------------------------------------------------------------
    server.delete("/banking/statements/:id", async (req, reply) => {
        try {
            if (!req.user) return reply.code(401).send({ error: "Unauthorized" })

            const { id } = req.params as { id: string }

            const oldRecord = await server.db
                .select()
                .from(statementallocations)
                .where(eq(statementallocations.id, id))
                .limit(1)

            const old = oldRecord[0]

            if (!old) return reply.code(404).send({ error: "Record not found" })

            await server.db
                .delete(statementallocations)
                .where(eq(statementallocations.id, id))

            await insertHistoryItem(server, {
                entity: "bankstatements",
                entityId: id,
                action: "deleted",
                created_by: req.user.user_id,
                tenant_id: req.user.tenant_id,
                oldVal: old,
                newVal: null,
                text: "Buchung gelöscht",
            })

            return reply.send({ success: true })

        } catch (err) {
            console.error(err)
            return reply.code(500).send({ error: "Failed to delete statement" })
        }
    })

}