import { PrismaService } from '@/src/core/prisma/prisma.service'
import { RedisService } from '@/src/core/redis/redis.service'
import { LoginInput } from '@/src/module/auth/session/inputs/login.input'
import { VerificationService } from '@/src/module/auth/verification/verification.service'
import { getSessionMetadata } from '@/src/shared/util/session-metadata.util'
import { destroySession, saveSession } from '@/src/shared/util/session.util'
import {
  BadRequestException,
  ConflictException,
  Injectable,
  NotFoundException,
  UnauthorizedException,
} from '@nestjs/common'
import { ConfigService } from '@nestjs/config'
import { verify } from 'argon2'
import { Request } from 'express'
import { SessionData } from 'express-session'
import { TOTP } from 'otpauth'

@Injectable()
export class SessionService {
  constructor(
    private readonly prismaService: PrismaService,
    private readonly redisService: RedisService,
    private readonly configService: ConfigService,
    private readonly verificationService: VerificationService,
  ) {}

  public async findByUser(req: Request) {
    const userId = req.user?.id

    if (!userId) {
      throw new NotFoundException('Пользователь не найден')
    }

    const keys = await this.redisService.keys('*')
    const userSessions: Request['session'][] = []

    for (const key of keys) {
      const sessionData = await this.redisService.get(key)
      if (sessionData) {
        const session = JSON.parse(sessionData) as Request['session']

        if (session.userId === userId) {
          userSessions.push({
            ...session,
            id: key.split(':')[1],
          } as Request['session'])
        }
      }
    }

    // eslint-disable-next-line @typescript-eslint/ban-ts-comment -- todo fixme
    // @ts-expect-error
    userSessions.sort((a, b) => b.createdAt - a.createdAt)

    return userSessions.filter(session => session.id !== req.session.id)
  }

  public async findCurrentSession(req: Request) {
    const sessionId = req.session.id
    const key = `${this.configService.getOrThrow<string>('SESSION_FOLDER')}${sessionId}`
    const sessionData = await this.redisService.get(key)

    if (!sessionData) {
      throw new NotFoundException('Сессия не найдена')
    }

    const session = JSON.parse(sessionData) as SessionData

    return {
      ...session,
      id: sessionId,
    }
  }

  public async login(req: Request, input: LoginInput, userAgent: string) {
    const { login, password, pin } = input

    const user = await this.prismaService.user.findFirst({ where: {
      OR: [
        { name: { equals: login } },
        { email: { equals: login } },
      ],
    } })

    if (!user) {
      throw new NotFoundException(`Пользователь не найден`)
    }

    const isValidPassword = await verify(user.password, password)
    if (!isValidPassword) {
      throw new UnauthorizedException('Логин или пароль неверный')
    }

    if (!user.isEmailVerified) {
      await this.verificationService.sendVerificationToken(user)
      throw new BadRequestException('Аккаунт не верифицирован. Проверьте свою почту для подтверждения')
    }

    if (user.isTotpEnabled) {
      if (!pin) {
        return {
          message: 'Необходимо ввести пин-код для завершения операции',
        }
      }

      const totp = new TOTP({
        issuer: 'TeaStream',
        label: user.email,
        algorithm: 'SHA-1',
        digits: 6,
        secret: user.totpSecret!,
      })

      const delta = totp.validate({ token: pin })

      if (delta === null) {
        throw new BadRequestException('Невереый код')
      }
    }

    return saveSession(req, user, getSessionMetadata(req, userAgent))
  }

  public async logout(req: Request) {
    return destroySession(req, this.configService)
  }

  public clearSession(req: Request) {
    req.res?.clearCookie(this.configService.getOrThrow('SESSION_NAME'))

    return true
  }

  public async remove(req: Request, id: string) {
    if (req.session.id === id) {
      throw new ConflictException('Текущую сессию удалить нельзя')
    }

    const key = `${this.configService.getOrThrow<string>('SESSION_FOLDER')}${id}`
    await this.redisService.del(key)

    return true
  }
}