import { z } from 'zod'
import { TRPCError } from '@trpc/server'
import { Prisma } from '@prisma/client'
import { router, protectedProcedure, adminProcedure } from '../trpc'
import {
  notifyRoundJury,
  NotificationTypes,
} from '../services/in-app-notification'

export const roundRouter = router({
  /**
   * List rounds for a program
   */
  list: protectedProcedure
    .input(z.object({ programId: z.string() }))
    .query(async ({ ctx, input }) => {
      return ctx.prisma.round.findMany({
        where: { programId: input.programId },
        orderBy: { sortOrder: 'asc' },
        include: {
          _count: {
            select: { projects: true, assignments: true },
          },
        },
      })
    }),

  /**
   * Get a single round with stats
   */
  get: protectedProcedure
    .input(z.object({ id: z.string() }))
    .query(async ({ ctx, input }) => {
      const round = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.id },
        include: {
          program: true,
          _count: {
            select: { projects: true, assignments: true },
          },
          evaluationForms: {
            where: { isActive: true },
            take: 1,
          },
        },
      })

      // Get evaluation stats
      const evaluationStats = await ctx.prisma.evaluation.groupBy({
        by: ['status'],
        where: {
          assignment: { roundId: input.id },
        },
        _count: true,
      })

      return {
        ...round,
        evaluationStats,
      }
    }),

  /**
   * Create a new round (admin only)
   */
  create: adminProcedure
    .input(
      z.object({
        programId: z.string(),
        name: z.string().min(1).max(255),
        roundType: z.enum(['FILTERING', 'EVALUATION', 'LIVE_EVENT']).default('EVALUATION'),
        requiredReviews: z.number().int().min(1).max(10).default(3),
        minAssignmentsPerJuror: z.number().int().min(1).max(50).default(5),
        maxAssignmentsPerJuror: z.number().int().min(1).max(100).default(20),
        sortOrder: z.number().int().optional(),
        settingsJson: z.record(z.unknown()).optional(),
        votingStartAt: z.date().optional(),
        votingEndAt: z.date().optional(),
        entryNotificationType: z.string().optional(),
      })
    )
    .mutation(async ({ ctx, input }) => {
      // Validate assignment constraints
      if (input.minAssignmentsPerJuror > input.maxAssignmentsPerJuror) {
        throw new TRPCError({
          code: 'BAD_REQUEST',
          message: 'Min assignments per juror must be less than or equal to max',
        })
      }

      // Validate dates
      if (input.votingStartAt && input.votingEndAt) {
        if (input.votingEndAt <= input.votingStartAt) {
          throw new TRPCError({
            code: 'BAD_REQUEST',
            message: 'End date must be after start date',
          })
        }
      }

      // Auto-set sortOrder if not provided (append to end)
      let sortOrder = input.sortOrder
      if (sortOrder === undefined) {
        const maxOrder = await ctx.prisma.round.aggregate({
          where: { programId: input.programId },
          _max: { sortOrder: true },
        })
        sortOrder = (maxOrder._max.sortOrder ?? -1) + 1
      }

      const { settingsJson, sortOrder: _so, ...rest } = input

      // Auto-activate if voting start date is in the past
      const now = new Date()
      const shouldAutoActivate = input.votingStartAt && input.votingStartAt <= now

      const round = await ctx.prisma.round.create({
        data: {
          ...rest,
          sortOrder,
          status: shouldAutoActivate ? 'ACTIVE' : 'DRAFT',
          settingsJson: settingsJson as Prisma.InputJsonValue ?? undefined,
        },
      })

      // For FILTERING rounds, automatically move all projects from the program to this round
      if (input.roundType === 'FILTERING') {
        await ctx.prisma.project.updateMany({
          where: {
            round: { programId: input.programId },
            roundId: { not: round.id },
          },
          data: {
            roundId: round.id,
            status: 'SUBMITTED',
          },
        })
      }

      // Audit log
      await ctx.prisma.auditLog.create({
        data: {
          userId: ctx.user.id,
          action: 'CREATE',
          entityType: 'Round',
          entityId: round.id,
          detailsJson: { ...rest, settingsJson } as Prisma.InputJsonValue,
          ipAddress: ctx.ip,
          userAgent: ctx.userAgent,
        },
      })

      return round
    }),

  /**
   * Update round details (admin only)
   */
  update: adminProcedure
    .input(
      z.object({
        id: z.string(),
        name: z.string().min(1).max(255).optional(),
        slug: z.string().min(1).max(100).regex(/^[a-z0-9-]+$/).optional().nullable(),
        roundType: z.enum(['FILTERING', 'EVALUATION', 'LIVE_EVENT']).optional(),
        requiredReviews: z.number().int().min(1).max(10).optional(),
        minAssignmentsPerJuror: z.number().int().min(1).max(50).optional(),
        maxAssignmentsPerJuror: z.number().int().min(1).max(100).optional(),
        submissionDeadline: z.date().optional().nullable(),
        votingStartAt: z.date().optional().nullable(),
        votingEndAt: z.date().optional().nullable(),
        settingsJson: z.record(z.unknown()).optional(),
        entryNotificationType: z.string().optional().nullable(),
      })
    )
    .mutation(async ({ ctx, input }) => {
      const { id, settingsJson, ...data } = input

      // Validate dates if both provided
      if (data.votingStartAt && data.votingEndAt) {
        if (data.votingEndAt <= data.votingStartAt) {
          throw new TRPCError({
            code: 'BAD_REQUEST',
            message: 'End date must be after start date',
          })
        }
      }

      // Validate assignment constraints if either is provided
      if (data.minAssignmentsPerJuror !== undefined || data.maxAssignmentsPerJuror !== undefined) {
        const existingRound = await ctx.prisma.round.findUnique({
          where: { id },
          select: { minAssignmentsPerJuror: true, maxAssignmentsPerJuror: true, status: true },
        })
        const newMin = data.minAssignmentsPerJuror ?? existingRound?.minAssignmentsPerJuror ?? 5
        const newMax = data.maxAssignmentsPerJuror ?? existingRound?.maxAssignmentsPerJuror ?? 20
        if (newMin > newMax) {
          throw new TRPCError({
            code: 'BAD_REQUEST',
            message: 'Min assignments per juror must be less than or equal to max',
          })
        }
      }

      // Check if we should auto-activate (if voting start is in the past and round is DRAFT)
      const now = new Date()
      let autoActivate = false
      if (data.votingStartAt && data.votingStartAt <= now) {
        const existingRound = await ctx.prisma.round.findUnique({
          where: { id },
          select: { status: true },
        })
        if (existingRound?.status === 'DRAFT') {
          autoActivate = true
        }
      }

      const round = await ctx.prisma.round.update({
        where: { id },
        data: {
          ...data,
          ...(autoActivate && { status: 'ACTIVE' }),
          settingsJson: settingsJson as Prisma.InputJsonValue ?? undefined,
        },
      })

      // Audit log
      await ctx.prisma.auditLog.create({
        data: {
          userId: ctx.user.id,
          action: 'UPDATE',
          entityType: 'Round',
          entityId: id,
          detailsJson: { ...data, settingsJson } as Prisma.InputJsonValue,
          ipAddress: ctx.ip,
          userAgent: ctx.userAgent,
        },
      })

      return round
    }),

  /**
   * Update round status (admin only)
   */
  updateStatus: adminProcedure
    .input(
      z.object({
        id: z.string(),
        status: z.enum(['DRAFT', 'ACTIVE', 'CLOSED', 'ARCHIVED']),
      })
    )
    .mutation(async ({ ctx, input }) => {
      // Get previous status and voting dates for audit
      const previousRound = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.id },
        select: { status: true, votingStartAt: true, votingEndAt: true },
      })

      const now = new Date()

      // When activating a round, if votingStartAt is in the future, update it to now
      // This ensures voting actually starts when the admin opens the round
      let votingStartAtUpdated = false
      const updateData: Parameters<typeof ctx.prisma.round.update>[0]['data'] = {
        status: input.status,
      }

      if (input.status === 'ACTIVE' && previousRound.status !== 'ACTIVE') {
        if (previousRound.votingStartAt && previousRound.votingStartAt > now) {
          updateData.votingStartAt = now
          votingStartAtUpdated = true
        }
      }

      const round = await ctx.prisma.round.update({
        where: { id: input.id },
        data: updateData,
      })

      // Map status to specific action name
      const statusActionMap: Record<string, string> = {
        ACTIVE: 'ROUND_ACTIVATED',
        CLOSED: 'ROUND_CLOSED',
        ARCHIVED: 'ROUND_ARCHIVED',
      }
      const action = statusActionMap[input.status] || 'UPDATE_STATUS'

      // Audit log
      await ctx.prisma.auditLog.create({
        data: {
          userId: ctx.user.id,
          action,
          entityType: 'Round',
          entityId: input.id,
          detailsJson: {
            status: input.status,
            previousStatus: previousRound.status,
            ...(votingStartAtUpdated && {
              votingStartAtUpdated: true,
              previousVotingStartAt: previousRound.votingStartAt,
              newVotingStartAt: now,
            }),
          },
          ipAddress: ctx.ip,
          userAgent: ctx.userAgent,
        },
      })

      // Notify jury members when round is activated
      if (input.status === 'ACTIVE' && previousRound.status !== 'ACTIVE') {
        // Get round details and assignment counts per user
        const roundDetails = await ctx.prisma.round.findUnique({
          where: { id: input.id },
          include: {
            _count: { select: { assignments: true } },
          },
        })

        // Get count of distinct jury members assigned
        const juryCount = await ctx.prisma.assignment.groupBy({
          by: ['userId'],
          where: { roundId: input.id },
          _count: true,
        })

        if (roundDetails && juryCount.length > 0) {
          const deadline = roundDetails.votingEndAt
            ? new Date(roundDetails.votingEndAt).toLocaleDateString('en-US', {
                weekday: 'long',
                year: 'numeric',
                month: 'long',
                day: 'numeric',
              })
            : undefined

          // Notify all jury members with assignments in this round
          await notifyRoundJury(input.id, {
            type: NotificationTypes.ROUND_NOW_OPEN,
            title: `${roundDetails.name} is Now Open`,
            message: `The evaluation round is now open. Please review your assigned projects and submit your evaluations before the deadline.`,
            linkUrl: `/jury/assignments`,
            linkLabel: 'Start Evaluating',
            priority: 'high',
            metadata: {
              roundName: roundDetails.name,
              projectCount: roundDetails._count.assignments,
              deadline,
            },
          })
        }
      }

      return round
    }),

  /**
   * Check if voting is currently open for a round
   */
  isVotingOpen: protectedProcedure
    .input(z.object({ id: z.string() }))
    .query(async ({ ctx, input }) => {
      const round = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.id },
      })

      const now = new Date()
      const isOpen =
        round.status === 'ACTIVE' &&
        round.votingStartAt !== null &&
        round.votingEndAt !== null &&
        now >= round.votingStartAt &&
        now <= round.votingEndAt

      return {
        isOpen,
        startsAt: round.votingStartAt,
        endsAt: round.votingEndAt,
        status: round.status,
      }
    }),

  /**
   * Get round progress statistics
   */
  getProgress: protectedProcedure
    .input(z.object({ id: z.string() }))
    .query(async ({ ctx, input }) => {
      const [totalProjects, totalAssignments, completedAssignments] =
        await Promise.all([
          ctx.prisma.project.count({ where: { roundId: input.id } }),
          ctx.prisma.assignment.count({ where: { roundId: input.id } }),
          ctx.prisma.assignment.count({
            where: { roundId: input.id, isCompleted: true },
          }),
        ])

      const evaluationsByStatus = await ctx.prisma.evaluation.groupBy({
        by: ['status'],
        where: {
          assignment: { roundId: input.id },
        },
        _count: true,
      })

      return {
        totalProjects,
        totalAssignments,
        completedAssignments,
        completionPercentage:
          totalAssignments > 0
            ? Math.round((completedAssignments / totalAssignments) * 100)
            : 0,
        evaluationsByStatus: evaluationsByStatus.reduce(
          (acc, curr) => {
            acc[curr.status] = curr._count
            return acc
          },
          {} as Record<string, number>
        ),
      }
    }),

  /**
   * Update or create evaluation form for a round (admin only)
   */
  updateEvaluationForm: adminProcedure
    .input(
      z.object({
        roundId: z.string(),
        criteria: z.array(
          z.object({
            id: z.string(),
            label: z.string().min(1),
            description: z.string().optional(),
            scale: z.number().int().min(1).max(10),
            weight: z.number().optional(),
            required: z.boolean(),
          })
        ),
      })
    )
    .mutation(async ({ ctx, input }) => {
      const { roundId, criteria } = input

      // Check if there are existing evaluations
      const existingEvaluations = await ctx.prisma.evaluation.count({
        where: {
          assignment: { roundId },
          status: { in: ['SUBMITTED', 'LOCKED'] },
        },
      })

      if (existingEvaluations > 0) {
        throw new TRPCError({
          code: 'BAD_REQUEST',
          message: 'Cannot modify criteria after evaluations have been submitted',
        })
      }

      // Get or create the active evaluation form
      const existingForm = await ctx.prisma.evaluationForm.findFirst({
        where: { roundId, isActive: true },
      })

      let form

      if (existingForm) {
        // Update existing form
        form = await ctx.prisma.evaluationForm.update({
          where: { id: existingForm.id },
          data: { criteriaJson: criteria },
        })
      } else {
        // Create new form
        form = await ctx.prisma.evaluationForm.create({
          data: {
            roundId,
            criteriaJson: criteria,
            isActive: true,
          },
        })
      }

      // Audit log
      await ctx.prisma.auditLog.create({
        data: {
          userId: ctx.user.id,
          action: 'UPDATE_EVALUATION_FORM',
          entityType: 'EvaluationForm',
          entityId: form.id,
          detailsJson: { roundId, criteriaCount: criteria.length },
          ipAddress: ctx.ip,
          userAgent: ctx.userAgent,
        },
      })

      return form
    }),

  /**
   * Get evaluation form for a round
   */
  getEvaluationForm: protectedProcedure
    .input(z.object({ roundId: z.string() }))
    .query(async ({ ctx, input }) => {
      return ctx.prisma.evaluationForm.findFirst({
        where: { roundId: input.roundId, isActive: true },
      })
    }),

  /**
   * Delete a round (admin only)
   * Cascades to projects, assignments, evaluations, etc.
   */
  delete: adminProcedure
    .input(z.object({ id: z.string() }))
    .mutation(async ({ ctx, input }) => {
      const round = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.id },
        include: {
          _count: { select: { projects: true, assignments: true } },
        },
      })

      await ctx.prisma.round.delete({
        where: { id: input.id },
      })

      // Audit log
      await ctx.prisma.auditLog.create({
        data: {
          userId: ctx.user.id,
          action: 'DELETE',
          entityType: 'Round',
          entityId: input.id,
          detailsJson: {
            name: round.name,
            status: round.status,
            projectsDeleted: round._count.projects,
            assignmentsDeleted: round._count.assignments,
          },
          ipAddress: ctx.ip,
          userAgent: ctx.userAgent,
        },
      })

      return round
    }),

  /**
   * Check if a round has any submitted evaluations
   */
  hasEvaluations: adminProcedure
    .input(z.object({ roundId: z.string() }))
    .query(async ({ ctx, input }) => {
      const count = await ctx.prisma.evaluation.count({
        where: {
          assignment: { roundId: input.roundId },
          status: { in: ['SUBMITTED', 'LOCKED'] },
        },
      })
      return count > 0
    }),

  /**
   * Assign projects from the program pool to a round
   */
  assignProjects: adminProcedure
    .input(
      z.object({
        roundId: z.string(),
        projectIds: z.array(z.string()).min(1),
      })
    )
    .mutation(async ({ ctx, input }) => {
      // Verify round exists and get programId
      const round = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.roundId },
      })

      // Update projects to assign them to this round
      const updated = await ctx.prisma.project.updateMany({
        where: {
          id: { in: input.projectIds },
          round: { programId: round.programId },
        },
        data: {
          roundId: input.roundId,
          status: 'SUBMITTED',
        },
      })

      if (updated.count === 0) {
        throw new TRPCError({
          code: 'BAD_REQUEST',
          message: 'No projects were assigned. Projects may not belong to this program.',
        })
      }

      // Audit log
      await ctx.prisma.auditLog.create({
        data: {
          userId: ctx.user.id,
          action: 'ASSIGN_PROJECTS_TO_ROUND',
          entityType: 'Round',
          entityId: input.roundId,
          detailsJson: { projectCount: updated.count },
          ipAddress: ctx.ip,
          userAgent: ctx.userAgent,
        },
      })

      return { assigned: updated.count }
    }),

  /**
   * Remove projects from a round
   */
  removeProjects: adminProcedure
    .input(
      z.object({
        roundId: z.string(),
        projectIds: z.array(z.string()).min(1),
      })
    )
    .mutation(async ({ ctx, input }) => {
      // Set roundId to null for these projects (remove from round)
      const updated = await ctx.prisma.project.updateMany({
        where: {
          roundId: input.roundId,
          id: { in: input.projectIds },
        },
        data: {
          roundId: null as unknown as string, // Projects need to be orphaned
        },
      })
      const deleted = { count: updated.count }

      // Audit log
      await ctx.prisma.auditLog.create({
        data: {
          userId: ctx.user.id,
          action: 'REMOVE_PROJECTS_FROM_ROUND',
          entityType: 'Round',
          entityId: input.roundId,
          detailsJson: { projectCount: deleted.count },
          ipAddress: ctx.ip,
          userAgent: ctx.userAgent,
        },
      })

      return { removed: deleted.count }
    }),

  /**
   * Advance projects from one round to the next
   * Creates new RoundProject entries in the target round (keeps them in source round too)
   */
  advanceProjects: adminProcedure
    .input(
      z.object({
        fromRoundId: z.string(),
        toRoundId: z.string(),
        projectIds: z.array(z.string()).min(1),
      })
    )
    .mutation(async ({ ctx, input }) => {
      // Verify both rounds exist and belong to the same program
      const [fromRound, toRound] = await Promise.all([
        ctx.prisma.round.findUniqueOrThrow({ where: { id: input.fromRoundId } }),
        ctx.prisma.round.findUniqueOrThrow({ where: { id: input.toRoundId } }),
      ])

      if (fromRound.programId !== toRound.programId) {
        throw new TRPCError({
          code: 'BAD_REQUEST',
          message: 'Rounds must belong to the same program',
        })
      }

      // Verify all projects are in the source round
      const sourceProjects = await ctx.prisma.project.findMany({
        where: {
          roundId: input.fromRoundId,
          id: { in: input.projectIds },
        },
        select: { id: true },
      })

      if (sourceProjects.length !== input.projectIds.length) {
        throw new TRPCError({
          code: 'BAD_REQUEST',
          message: 'Some projects are not in the source round',
        })
      }

      // Move projects to target round
      const updated = await ctx.prisma.project.updateMany({
        where: {
          id: { in: input.projectIds },
          roundId: input.fromRoundId,
        },
        data: {
          roundId: input.toRoundId,
          status: 'SUBMITTED',
        },
      })
      const created = { count: updated.count }

      // Audit log
      await ctx.prisma.auditLog.create({
        data: {
          userId: ctx.user.id,
          action: 'ADVANCE_PROJECTS',
          entityType: 'Round',
          entityId: input.toRoundId,
          detailsJson: {
            fromRoundId: input.fromRoundId,
            toRoundId: input.toRoundId,
            projectCount: created.count,
          },
          ipAddress: ctx.ip,
          userAgent: ctx.userAgent,
        },
      })

      return { advanced: created.count }
    }),

  /**
   * Reorder rounds within a program
   */
  reorder: adminProcedure
    .input(
      z.object({
        programId: z.string(),
        roundIds: z.array(z.string()).min(1),
      })
    )
    .mutation(async ({ ctx, input }) => {
      // Update sortOrder for each round based on array position
      await ctx.prisma.$transaction(
        input.roundIds.map((roundId, index) =>
          ctx.prisma.round.update({
            where: { id: roundId },
            data: { sortOrder: index },
          })
        )
      )

      // Audit log
      await ctx.prisma.auditLog.create({
        data: {
          userId: ctx.user.id,
          action: 'REORDER_ROUNDS',
          entityType: 'Program',
          entityId: input.programId,
          detailsJson: { roundIds: input.roundIds },
          ipAddress: ctx.ip,
          userAgent: ctx.userAgent,
        },
      })

      return { success: true }
    }),
})