import { MailService } from "#services/mail-service.js";
import { logger } from "#logger";
import { selPool, updPool } from "#db";
import { sql } from "slonik";

import { DbSchema } from "#db-schema";
import { z } from "zod";

// dayjs
import { dayjs, DayjsUtils } from "#dayjs";
import { config } from "#config";

class confirmPinsService {
  // privalte
  private genRandom4DigitNumber() {
    return Math.floor(1000 + Math.random() * 9000);
  }

  private async deleteConfirmPin(transactionId: string) {
    await updPool.query(
      sql.unsafe`
      delete from 
        usr.confirm_pins 
      where 
        transaction_id = ${transactionId}`,
    );
  }

  private async pinTriesIncrement(transactionId: string) {
    await updPool.query(
      sql.unsafe`
      update 
        usr.confirm_pins 
      set 
        wrong_pin_tries = wrong_pin_tries + 1 
      where 
        transaction_id = ${transactionId}`,
    );
  }
  //
  // public
  //
  async sendConfirmPin(transactionId: string, email: string) {
    const confirmPin = this.genRandom4DigitNumber();
    // удаляем если пин уже есть
    await this.deleteConfirmPin(transactionId);
    // отправка
    const mailBody = `
    <div>
      <h1>Ваш временный код:</h1>
      <h4> <a href="${confirmPin}">${confirmPin}</a> </h4>
    </div>
`;
    await MailService.sendMail(email, "Ваш код для EVENT", mailBody);
    // бд
    await updPool.query(
      sql.unsafe`
      insert into usr.confirm_pins (
        transaction_id,
        email,
        confirm_pin,
        create_time)
      values (
        ${transactionId}, 
        ${email}, 
        ${confirmPin}, 
        ${DayjsUtils.createDayjsUtcWithoutOffset().toISOString()})`,
    );
    logger.info("Отправлен временный код: ", {
      email,
      confirmPin,
    });
  }

  async checkConfirmPin(
    transactionId: string,
    confirmPin: string,
  ): Promise<
    | { status: "correct"; email: string }
    | { status: "rotten" }
    | { status: "tooManyTries" }
    | {
        status: "wrong";
        triesRemained: number;
      }
  > {
    const pinInfo = await selPool.maybeOne(
      sql.type(
        z.object({
          confirmPin: DbSchema.usr.confirmPins.confirmPin,
          email: DbSchema.usr.confirmPins.email,
          createTime: DbSchema.usr.confirmPins.createTime,
          wrongPinTries: DbSchema.usr.confirmPins.wrongPinTries,
        }),
      )`
      select 
        confirm_pin as "confirmPin", 
        email, 
        create_time as "createTime", 
        wrong_pin_tries as "wrongPinTries"
      from 
        usr.confirm_pins 
      where 
        transaction_id = ${transactionId}`,
    );

    // не существует
    if (!pinInfo) {
      return { status: "rotten" };
    }

    // много попыток
    if (pinInfo.wrongPinTries > config.CONFIRM_PIN_MAX_TRIES - 1) {
      return { status: "tooManyTries" };
    }

    // просрочка
    if (
      DayjsUtils.createDayjsUtcWithoutOffset().isAfter(
        dayjs
          .utc(pinInfo.createTime)
          .add(config.CONFIRM_PIN_LIFETIME_MINS, "minutes"),
      )
    ) {
      await this.deleteConfirmPin(transactionId);
      return { status: "rotten" };
    }

    // неправильный
    if (pinInfo.confirmPin !== confirmPin) {
      await this.pinTriesIncrement(transactionId);

      const triesRemained =
        config.CONFIRM_PIN_MAX_TRIES - 1 - pinInfo.wrongPinTries;

      return {
        status: "wrong",
        triesRemained,
      };
    }

    // правильный
    await this.deleteConfirmPin(transactionId);
    return { status: "correct", email: pinInfo.email };
  }
}

export const ConfirmPinsService = new confirmPinsService();