// deno-lint-ignore-file ban-ts-comment
import "jsr:@std/dotenv/load";
import { encodeHex } from "jsr:@std/encoding/hex";
import { getHostUrl } from "../utils.ts";
import { STATUS_CODE } from "$fresh/server.ts";

const config = {
  clientId: Deno.env.get("VIPPS_CLIENT_ID"),
  clientSecret: Deno.env.get("VIPPS_CLIENT_SECRET"),
  ocpApimSubscriptionKeyPrimary: Deno.env.get(
    "VIPPS_OCP_APIM_SUBSCRIPTION_KEY_PRIMARY",
  ),
  ocpApimSubscriptionKeySecondary: Deno.env.get(
    "VIPPS_OCM_APIM_SUBSCRIPTION_KEY_SECONDARY",
  ),
  msn: Deno.env.get("VIPPS_MSN"),
  baseUrl: Deno.env.get("VIPPS_API_BASE_URL"),
};

// ensure all environment variables are set
for (const [key, value] of Object.entries(config)) {
  if (!value) {
    throw new Error(`Missing environment variable: ${key}`);
  }
}

const standardVippsHeaders = {
  "Content-Type": "application/json",
  "Ocp-Apim-Subscription-Key": config.ocpApimSubscriptionKeyPrimary,
  "Merchant-Serial-Number": config.msn,
  "Vipps-System-Name": "Krets AS",
} as const;

const getAccessToken = async function () {
  console.log(`Fetching ${`${config.baseUrl}/accesstoken/get`}`);
  const response = await fetch(`${config.baseUrl}/accesstoken/get`, {
    method: "POST",
    // @ts-ignore
    headers: {
      client_id: config.clientId,
      client_secret: config.clientSecret,
      ...standardVippsHeaders,
    },
  });

  const data = await response.json();
  return data.access_token as string;
};

export const createAgreement = async function (email: string) {
  const token = await getAccessToken();
  const amount = 5000; // 50 NOK
  const response = await fetch(`${config.baseUrl}/recurring/v3/agreements/`, {
    method: "POST",
    // @ts-ignore
    headers: {
      authorization: `Bearer ${token}`,
      // anonymized and trimmed to not be too long (then it fails)
      "Idempotency-Key": `${encodeHex(email).slice(0, 10)}-${Date.now()}`,
      ...standardVippsHeaders,
    },
    body: JSON.stringify({
      interval: {
        unit: "MONTH",
        count: 1,
      },
      initialCharge: {
        amount: amount,
        description: "Initial charge",
        transactionType: "DIRECT_CAPTURE",
      },
      pricing: {
        amount: amount,
        currency: "NOK",
      },
      // email is used to identify the user in the success page
      merchantRedirectUrl: `${getHostUrl()}/donations-success?email=${email}`,
      merchantAgreementUrl: `${getHostUrl()}`,
      productName: "Månedlig støtte til NRSS",
    }),
  });

  if (response.status === STATUS_CODE.Created) {
    const body = response.json();
    return body as unknown as {
      vippsConfirmationUrl: string;
      agreementId: string;
    };
  } else {
    const errorMessage = `Failed to create Vipps agreement ${response.status} ${await response.text()}`;
    console.error(errorMessage);
    return new Error(errorMessage);
  }
};

export const getAgreement = async function (agreementId: string): Promise<
  | {
    status: "PENDING" | "ACTIVE" | "STOPPED" | "EXPIRED";
  }
  | Error
> {
  const token = await getAccessToken();
  const response = await fetch(
    `${config.baseUrl}/recurring/v3/agreements/${agreementId}`,
    {
      // @ts-ignore
      headers: {
        authorization: `Bearer ${token}`,
        ...standardVippsHeaders,
      },
    },
  );

  if (response.status === STATUS_CODE.OK) {
    return response.json();
  } else {
    const errorMessage = `Failed to get Vipps agreement ${response.status} ${await response.text()}`;
    console.error(errorMessage);
    return new Error(errorMessage);
  }
};

export const cancelAgreement = async function (agreementId: string) {
  const token = await getAccessToken();
  const response = await fetch(
    `${config.baseUrl}/recurring/v3/agreements/${agreementId}`,
    {
      method: "PATCH",
      // @ts-ignore
      headers: {
        authorization: `Bearer ${token}`,
        "Idempotency-Key": `${agreementId}-${Date.now()}`,
        ...standardVippsHeaders,
      },
      body: JSON.stringify({
        status: "STOPPED",
      }),
    },
  );

  if (response.status === STATUS_CODE.NoContent) {
    return true;
  } else {
    const errorMessage = `Failed to cancel Vipps agreement ${response.status} ${await response.text()}`;
    console.error(errorMessage);
    return new Error(errorMessage);
  }
};