import * as GQL from '../types';
import { BaseService } from './base';
import { OrdersService } from './orders';
import { type VariablesOf } from '@graphql-typed-document-node/core';
import dayjs from 'dayjs';
import minMax from 'dayjs/plugin/minMax';

if (!dayjs.prototype.minMax) {
  dayjs.extend(minMax);
}

export const ERRORS = {
  FAILED_TO_CREATE_TRIAL_SUBSCRIPTION: 'Не удалось оформить доступ к пробному периоду',
  SUBSCRIPTION_PRICES_NOT_FOUND: 'Цены Pro доступа не найдены',
  SUBSCRIPTION_SETTING_NOT_FOUND: 'Настройки Pro доступа не найдены',
  TRIAL_PERIOD_ALREADY_USED: 'Пробный период уже был использован',
  TRIAL_PERIOD_NOT_ACTIVE: 'Пробный период неактивен',
  TRIAL_PERIOD_NOT_FOUND: 'Пробный период не найден',
};

export class SubscriptionsService extends BaseService {
  async createOrUpdateSubscription(
    payload: { period: GQL.Enum_Subscriptionprice_Period },
    paymentId?: string,
  ) {
    const { subscriptionPrices } = await this.getSubscriptionPrices({
      filters: { period: { eq: payload.period } },
    });

    const subscriptionPrice = subscriptionPrices[0];
    if (!subscriptionPrice) throw new Error('Subscription price not found');

    const { subscription: existingSubscription } = await this.getSubscription({
      telegramId: this._user.telegramId,
    });

    const newExpiresAt = dayjs
      .max(dayjs(existingSubscription?.expiresAt), dayjs())
      .add(subscriptionPrice.days, 'day');

    const { customer } = await this.checkIsBanned();

    const result = await this.createSubscription({
      data: {
        active: true,
        customer: customer.documentId,
        expiresAt: newExpiresAt.toISOString(),
      },
    });

    // Добавляем в последнюю подписку ссылку на новую только что созданную
    if (result?.createSubscription && existingSubscription)
      await this.updateSubscription({
        data: {
          active: true,
          nextSubscription: result.createSubscription.documentId,
        },
        documentId: existingSubscription?.documentId,
      });

    await this.createSubscriptionHistory({
      data: {
        amount: subscriptionPrice.amount,
        currency: 'RUB',
        description: existingSubscription ? 'Продление Pro доступа' : 'Новая подписка',
        paymentId,
        period: subscriptionPrice.period,
        source: GQL.Enum_Subscriptionhistory_Source.Payment,
        state: GQL.Enum_Subscriptionhistory_State.Success,
        subscription: result?.createSubscription?.documentId,
        subscription_price: subscriptionPrice.documentId,
      },
    });

    return {
      expiresAt: newExpiresAt.toDate(),
      formattedDate: newExpiresAt.toDate().toLocaleDateString('ru-RU', {
        day: '2-digit',
        month: '2-digit',
        year: 'numeric',
      }),
    };
  }

  async createSubscription(variables: VariablesOf<typeof GQL.CreateSubscriptionDocument>) {
    await this.checkIsBanned();

    const { mutate } = await this.getGraphQLClient();

    const mutationResult = await mutate({
      mutation: GQL.CreateSubscriptionDocument,
      variables,
    });

    const error = mutationResult.errors?.at(0);
    if (error) throw new Error(error.message);

    return mutationResult.data;
  }

  async createSubscriptionHistory(
    variables: VariablesOf<typeof GQL.CreateSubscriptionHistoryDocument>,
  ) {
    await this.checkIsBanned();

    const { mutate } = await this.getGraphQLClient();

    const mutationResult = await mutate({
      mutation: GQL.CreateSubscriptionHistoryDocument,
      variables,
    });

    const error = mutationResult.errors?.at(0);
    if (error) throw new Error(error.message);

    return mutationResult.data;
  }

  async createTrialSubscription() {
    // Получаем пользователя и проверяем бан
    const { customer } = await this.checkIsBanned();

    // Проверяем, не использовал ли пользователь уже пробный период
    const hasTrial = await this.hasTrialSubscription();
    if (hasTrial) throw new Error(ERRORS.TRIAL_PERIOD_ALREADY_USED);

    // Получаем цены подписки для определения длительности пробного периода
    const { subscriptionPrices } = await this.getSubscriptionPrices({
      filters: {
        active: {
          eq: true,
        },
      },
    });
    if (!subscriptionPrices) throw new Error(ERRORS.SUBSCRIPTION_PRICES_NOT_FOUND);

    // Ищем пробный период
    const trialPrice = subscriptionPrices.find(
      (price) => price?.period === GQL.Enum_Subscriptionprice_Period.Trial,
    );
    if (!trialPrice) throw new Error(ERRORS.TRIAL_PERIOD_NOT_FOUND);
    if (!trialPrice.active) throw new Error(ERRORS.TRIAL_PERIOD_NOT_ACTIVE);

    const trialPeriodDays = trialPrice?.days;
    const now = dayjs();
    const expiresAt = now.add(trialPeriodDays, 'day');

    // Создаем пробную подписку
    const subscriptionData = await this.createSubscription({
      data: {
        active: true,
        customer: customer?.documentId,
        expiresAt: expiresAt.toISOString(),
      },
    });

    if (!subscriptionData?.createSubscription) {
      throw new Error(ERRORS.FAILED_TO_CREATE_TRIAL_SUBSCRIPTION);
    }

    const subscription = subscriptionData.createSubscription;

    // Создаем запись в истории подписки
    await this.createSubscriptionHistory({
      data: {
        amount: 0,
        currency: 'RUB',
        description: `Пробный период на ${trialPeriodDays} дней`,
        period: trialPrice.period,
        source: GQL.Enum_Subscriptionhistory_Source.Trial,
        state: GQL.Enum_Subscriptionhistory_State.Success,
        subscription: subscription.documentId,
      },
    });

    return subscriptionData;
  }

  async getSubscription({
    telegramId,
  }: Pick<VariablesOf<typeof GQL.GetCustomerDocument>, 'telegramId'>) {
    await this.checkIsBanned();

    const data = await this.getSubscriptions({
      filters: {
        active: {
          eq: true,
        },
        customer: {
          telegramId: { eq: telegramId },
        },
      },
    });

    const subscription = data.subscriptions.find((x) => !x?.nextSubscription?.documentId);
    const remainingDays = subscription ? this.getRemainingDays(subscription) : 0;
    const hasActiveSubscription = subscription?.active && remainingDays > 0;

    const { maxOrdersPerMonth, remainingOrdersCount } = await this.getRemainingOrdersCount();

    return {
      hasActiveSubscription,
      maxOrdersPerMonth,
      remainingDays,
      remainingOrdersCount,
      subscription,
    };
  }

  async getSubscriptionHistory(variables: VariablesOf<typeof GQL.GetSubscriptionHistoryDocument>) {
    const { query } = await this.getGraphQLClient();

    const result = await query({
      query: GQL.GetSubscriptionHistoryDocument,
      variables,
    });

    const subscriptionHistories = result.data.subscriptionHistories;

    return { subscriptionHistories };
  }

  async getSubscriptionPrices(variables?: VariablesOf<typeof GQL.GetSubscriptionPricesDocument>) {
    await this.checkIsBanned();

    const { query } = await this.getGraphQLClient();

    const result = await query({
      query: GQL.GetSubscriptionPricesDocument,
      variables,
    });

    return result.data;
  }

  async getSubscriptions(variables?: VariablesOf<typeof GQL.GetSubscriptionsDocument>) {
    await this.checkIsBanned();

    const { query } = await this.getGraphQLClient();

    const result = await query({
      query: GQL.GetSubscriptionsDocument,
      variables,
    });

    return result.data;
  }

  async getSubscriptionSettings() {
    await this.checkIsBanned();

    const { query } = await this.getGraphQLClient();

    const result = await query({
      query: GQL.GetSubscriptionSettingsDocument,
    });

    return result.data;
  }

  async hasTrialSubscription() {
    const { customer } = await this._getUser();

    const { subscriptionHistories } = await this.getSubscriptionHistory({
      filters: {
        or: [
          {
            source: {
              eq: GQL.Enum_Subscriptionhistory_Source.Trial,
            },
          },
          {
            period: {
              eq: GQL.Enum_Subscriptionprice_Period.Trial,
            },
          },
        ],

        subscription: {
          customer: {
            documentId: {
              eq: customer?.documentId,
            },
          },
        },
      },
    });

    return subscriptionHistories?.some(
      (history) => history?.state === GQL.Enum_Subscriptionhistory_State.Success,
    );
  }

  async updateSubscription(variables: VariablesOf<typeof GQL.UpdateSubscriptionDocument>) {
    await this.checkIsBanned();

    const { mutate } = await this.getGraphQLClient();

    const mutationResult = await mutate({
      mutation: GQL.UpdateSubscriptionDocument,
      variables,
    });

    const error = mutationResult.errors?.at(0);
    if (error) throw new Error(error.message);

    return mutationResult.data;
  }

  async updateSubscriptionHistory(
    variables: VariablesOf<typeof GQL.UpdateSubscriptionHistoryDocument>,
  ) {
    await this.checkIsBanned();

    const { mutate } = await this.getGraphQLClient();

    const mutationResult = await mutate({
      mutation: GQL.UpdateSubscriptionHistoryDocument,
      variables,
    });

    const error = mutationResult.errors?.at(0);
    if (error) throw new Error(error.message);

    return mutationResult.data;
  }

  private getRemainingDays(subscription: GQL.SubscriptionFieldsFragment) {
    if (!subscription) return 0;

    const remainingDays = dayjs(subscription?.expiresAt).diff(dayjs(), 'day', true);

    if (remainingDays <= 0) return 0;

    return Math.ceil(remainingDays);
  }

  private async getRemainingOrdersCount() {
    const ordersService = new OrdersService(this._user);

    const now = dayjs();

    const { orders } = await ordersService.getOrders({
      filters: {
        datetime_end: {
          lte: now.endOf('month').toISOString(),
        },
        datetime_start: {
          gte: now.startOf('month').toISOString(),
        },

        state: {
          eq: GQL.Enum_Order_State.Completed,
        },
      },
    });

    const { subscriptionSetting } = await this.getSubscriptionSettings();

    if (!subscriptionSetting) throw new Error(ERRORS.SUBSCRIPTION_SETTING_NOT_FOUND);

    const { maxOrdersPerMonth } = subscriptionSetting;

    let remainingOrdersCount = maxOrdersPerMonth - (orders?.length ?? 0);

    if (remainingOrdersCount < 0) remainingOrdersCount = 0;

    return { maxOrdersPerMonth, remainingOrdersCount };
  }
}