const { NotFoundError, DatabaseError } = require('../../shared/errors');
const { Op } = require('sequelize');

class FriendRequestsRepository {
  constructor({ sequelize }) {
    this.sequelize = sequelize;
    this.FriendRequest = sequelize.models.FriendRequest;
    this.User = sequelize.models.User;
  }

  async findById(id) {
    try {
      const request = await this.FriendRequest.findByPk(id, {
        include: [
          { model: this.User, as: 'fromUser' },
          { model: this.User, as: 'toUser' },
        ],
      });
      if (!request) {
        throw new NotFoundError('Friend request not found');
      }
      return request;
    } catch (error) {
      if (error instanceof NotFoundError) throw error;
      throw new DatabaseError(`Failed to fetch friend request with id ${id}`, error);
    }
  }

  async findPendingByUserId(userId) {
    try {
      return await this.FriendRequest.findAll({
        where: {
          toUserId: userId,
          status: 'PENDING',
        },
        include: [
          { model: this.User, as: 'fromUser' },
          { model: this.User, as: 'toUser' },
        ],
      });
    } catch (error) {
      throw new DatabaseError(
        `Failed to fetch pending requests for user ${userId}`,
        error
      );
    }
  }

  async findExisting(fromUserId, toUserId) {
    try {
      return await this.FriendRequest.findOne({
        where: {
          [Op.or]: [
            { fromUserId, toUserId },
            { fromUserId: toUserId, toUserId: fromUserId },
          ],
          status: 'PENDING',
        },
      });
    } catch (error) {
      throw new DatabaseError('Failed to check existing friend request', error);
    }
  }

  async create(fromUserId, toUserId) {
    try {
      return await this.FriendRequest.create({
        fromUserId,
        toUserId,
        status: 'PENDING',
      });
    } catch (error) {
      throw new DatabaseError('Failed to create friend request', error);
    }
  }

  async updateStatus(id, status) {
    try {
      const request = await this.findById(id);
      return await request.update({ status });
    } catch (error) {
      if (error instanceof NotFoundError) throw error;
      throw new DatabaseError('Failed to update friend request status', error);
    }
  }

  async delete(id) {
    try {
      const request = await this.findById(id);
      await request.destroy();
      return true;
    } catch (error) {
      if (error instanceof NotFoundError) throw error;
      throw new DatabaseError('Failed to delete friend request', error);
    }
  }
}

module.exports = FriendRequestsRepository;