import { Inject, Injectable, Logger } from '@nestjs/common'
import { Pothos, PothosRef, PothosSchema, SchemaBuilderToken } from '@smatch-corp/nestjs-pothos'
import { DateTimeUtils } from 'src/common/utils/datetime.utils'
import { Builder } from '../Graphql/graphql.builder'
import { PrismaService } from '../Prisma/prisma.service'

@Injectable()
export class WorkshopSubscriptionSchema extends PothosSchema {
  constructor(
    @Inject(SchemaBuilderToken) private readonly builder: Builder,
    private readonly prisma: PrismaService,
  ) {
    super()
  }
  @PothosRef()
  workshopSubscription() {
    return this.builder.prismaObject('WorkshopSubscription', {
      description: 'A workshop subscription in the system.',
      fields: (t) => ({
        userId: t.exposeID('userId', {
          description: 'The ID of the user who subscribed to the workshop.',
        }),
        workshopId: t.exposeID('workshopId', {
          description: 'The ID of the workshop that the user subscribed to.',
        }),
        user: t.relation('user', {
          description: 'The user who subscribed to the workshop.',
        }),
        workshop: t.relation('workshop', {
          description: 'The workshop that the user subscribed to.',
        }),
        createdAt: t.expose('createdAt', {
          type: 'DateTime',
          description: 'The date and time the workshop subscription was created.',
        }),
        notified: t.exposeBoolean('notified', {
          description: 'Whether the user has been notified about the workshop.',
        }),
      }),
    })
  }

  @Pothos()
  init(): void {
    this.builder.queryFields((t) => ({
      workshopSubscription: t.prismaField({
        type: this.workshopSubscription(),
        args: this.builder.generator.findUniqueArgs('WorkshopSubscription'),
        description: 'Retrieve a single workshop subscription by its unique identifier.',
        resolve: async (query, _root, args) => {
          return await this.prisma.workshopSubscription.findUnique({
            ...query,
            where: args.where,
          })
        },
      }),
      workshopSubscriptions: t.prismaField({
        type: [this.workshopSubscription()],
        args: this.builder.generator.findManyArgs('WorkshopSubscription'),
        description: 'Retrieve a list of workshop subscriptions with optional filtering, ordering, and pagination.',
        resolve: async (query, _root, args, _ctx) => {
          return await this.prisma.workshopSubscription.findMany({
            ...query,
            skip: args.skip ?? undefined,
            take: args.take ?? undefined,
            orderBy: args.orderBy ?? undefined,
            where: args.filter ?? undefined,
          })
        },
      }),
      subscribedWorkshops: t.prismaField({
        type: [this.workshopSubscription()],
        description: 'Retrieve a list of workshops that the current user is subscribed to.',
        resolve: async (query, _root, _args, ctx, _info) => {
          if (!ctx.me) {
            throw new Error('User is not authenticated')
          }
          return await this.prisma.workshopSubscription.findMany({
            ...query,
            where: {
              userId: ctx.me.id,
            },
          })
        },
      }),
    }))
    this.builder.mutationFields((t) => ({
      subscribeToWorkshop: t.prismaField({
        type: this.workshopSubscription(),
        args: {
          workshopId: t.arg.string({
            description: 'The ID of the workshop to subscribe to.',
            required: true,
          }),
        },
        resolve: async (_query, _root, args, ctx) => {
          const userId = ctx.me?.id
          // retrieve the workshop
          const workshop = await this.prisma.workshop.findUnique({
            where: { id: args.workshopId },
          })
          if (!workshop) {
            throw new Error('Workshop not found')
          }
          if (!userId) {
            throw new Error('User not authenticated')
          }
          // check if workshop is in the future
          if (workshop.date < DateTimeUtils.now().toJSDate()) {
            throw new Error('Workshop has already started or is over')
          }
          // check if user is already subscribed to the workshop
          const existingSubscription = await this.prisma.workshopSubscription.findFirst({
            where: { userId, workshopId: args.workshopId },
          })
          if (existingSubscription) {
            throw new Error('User already subscribed to workshop')
          }
          // create the workshop subscription
          const result = await this.prisma.workshopSubscription.create({
            data: {
              userId,
              workshopId: args.workshopId,
            },
          })
          // update participant count by querying the workshop subscription
          const participantCount = await this.prisma.workshopSubscription.count({
            where: { workshopId: args.workshopId },
          })
          await this.prisma.workshop.update({
            where: { id: args.workshopId },
            data: {
              registeredParticipants: participantCount,
            },
          })
          return result
        },
      }),
    }))
  }
}