MOPC-Portal/src/server/routers/assignment.ts

import { z } from 'zod'
import { TRPCError } from '@trpc/server'
import { router, protectedProcedure, adminProcedure } from '../trpc'
import { getUserAvatarUrl } from '../utils/avatar-url'
import {
  generateAIAssignments,
  generateFallbackAssignments,
  type AssignmentProgressCallback,
} from '../services/ai-assignment'
import { isOpenAIConfigured } from '@/lib/openai'
import { prisma } from '@/lib/prisma'
import {
  createNotification,
  createBulkNotifications,
  notifyAdmins,
  NotificationTypes,
} from '../services/in-app-notification'
import { logAudit } from '@/server/utils/audit'

/**
 * Reassign a project after a juror declares COI.
 * Deletes the old assignment, finds an eligible replacement juror, and creates a new assignment.
 * Returns the new juror info or null if no eligible juror found.
 */
export async function reassignAfterCOI(params: {
  assignmentId: string
  auditUserId?: string
  auditIp?: string
  auditUserAgent?: string
}): Promise<{ newJurorId: string; newJurorName: string; newAssignmentId: string } | null> {
  const assignment = await prisma.assignment.findUnique({
    where: { id: params.assignmentId },
    include: {
      round: { select: { id: true, name: true, configJson: true, juryGroupId: true } },
      project: { select: { id: true, title: true } },
      user: { select: { id: true, name: true, email: true } },
    },
  })

  if (!assignment) return null

  const { roundId, projectId } = assignment
  const config = (assignment.round.configJson ?? {}) as Record<string, unknown>
  const maxAssignmentsPerJuror =
    (config.maxLoadPerJuror as number) ??
    (config.maxAssignmentsPerJuror as number) ??
    20

  // Get all jurors already assigned to this project in this round
  const existingAssignments = await prisma.assignment.findMany({
    where: { roundId, projectId },
    select: { userId: true },
  })
  const alreadyAssignedIds = new Set(existingAssignments.map((a) => a.userId))

  // Get all COI records for this project (any juror who declared conflict)
  const coiRecords = await prisma.conflictOfInterest.findMany({
    where: { projectId, hasConflict: true },
    select: { userId: true },
  })
  const coiUserIds = new Set(coiRecords.map((c) => c.userId))

  // Find eligible jurors: in the jury group (or all JURY_MEMBERs), not already assigned, no COI
  let candidateJurors: { id: string; name: string | null; email: string; maxAssignments: number | null }[]

  if (assignment.round.juryGroupId) {
    const members = await prisma.juryGroupMember.findMany({
      where: { juryGroupId: assignment.round.juryGroupId },
      include: { user: { select: { id: true, name: true, email: true, maxAssignments: true, status: true } } },
    })
    candidateJurors = members
      .filter((m) => m.user.status === 'ACTIVE')
      .map((m) => m.user)
  } else {
    // No jury group — scope to jurors already assigned to this round
    const roundJurorIds = await prisma.assignment.findMany({
      where: { roundId },
      select: { userId: true },
      distinct: ['userId'],
    })
    const activeRoundJurorIds = roundJurorIds.map((a) => a.userId)

    candidateJurors = activeRoundJurorIds.length > 0
      ? await prisma.user.findMany({
          where: {
            id: { in: activeRoundJurorIds },
            role: 'JURY_MEMBER',
            status: 'ACTIVE',
          },
          select: { id: true, name: true, email: true, maxAssignments: true },
        })
      : []
  }

  // Filter out already assigned and COI jurors
  const eligible = candidateJurors.filter(
    (j) => !alreadyAssignedIds.has(j.id) && !coiUserIds.has(j.id)
  )

  if (eligible.length === 0) return null

  // Get current assignment counts for eligible jurors in this round
  const counts = await prisma.assignment.groupBy({
    by: ['userId'],
    where: { roundId, userId: { in: eligible.map((j) => j.id) } },
    _count: true,
  })
  const countMap = new Map(counts.map((c) => [c.userId, c._count]))

  // Find jurors under their limit, sorted by fewest assignments (load balancing)
  const underLimit = eligible
    .map((j) => ({
      ...j,
      currentCount: countMap.get(j.id) || 0,
      effectiveMax: j.maxAssignments ?? maxAssignmentsPerJuror,
    }))
    .filter((j) => j.currentCount < j.effectiveMax)
    .sort((a, b) => a.currentCount - b.currentCount)

  if (underLimit.length === 0) return null

  const replacement = underLimit[0]

  // Delete old assignment and create replacement atomically.
  // Cascade deletes COI record and any draft evaluation.
  const newAssignment = await prisma.$transaction(async (tx) => {
    await tx.assignment.delete({ where: { id: params.assignmentId } })
    return tx.assignment.create({
      data: {
        userId: replacement.id,
        projectId,
        roundId,
        juryGroupId: assignment.juryGroupId ?? assignment.round.juryGroupId ?? undefined,
        isRequired: assignment.isRequired,
        method: 'MANUAL',
      },
    })
  })

  // Notify the replacement juror
  await createNotification({
    userId: replacement.id,
    type: NotificationTypes.ASSIGNED_TO_PROJECT,
    title: 'New Project Assigned',
    message: `You have been assigned to evaluate "${assignment.project.title}" for ${assignment.round.name}.`,
    linkUrl: `/jury/competitions`,
    linkLabel: 'View Assignment',
    metadata: { projectId, roundName: assignment.round.name },
  })

  // Notify admins of the reassignment
  await notifyAdmins({
    type: NotificationTypes.EVALUATION_MILESTONE,
    title: 'COI Auto-Reassignment',
    message: `Project "${assignment.project.title}" was reassigned from ${assignment.user.name || assignment.user.email} to ${replacement.name || replacement.email} due to conflict of interest.`,
    linkUrl: `/admin/rounds/${roundId}`,
    linkLabel: 'View Round',
    metadata: {
      projectId,
      oldJurorId: assignment.userId,
      newJurorId: replacement.id,
      reason: 'COI',
    },
  })

  // Audit
  if (params.auditUserId) {
    await logAudit({
      prisma,
      userId: params.auditUserId,
      action: 'COI_REASSIGNMENT',
      entityType: 'Assignment',
      entityId: newAssignment.id,
      detailsJson: {
        oldAssignmentId: params.assignmentId,
        oldJurorId: assignment.userId,
        newJurorId: replacement.id,
        projectId,
        roundId,
      },
      ipAddress: params.auditIp,
      userAgent: params.auditUserAgent,
    })
  }

  return {
    newJurorId: replacement.id,
    newJurorName: replacement.name || replacement.email,
    newAssignmentId: newAssignment.id,
  }
}

/** Evaluation statuses that are safe to move (not yet finalized). */
const MOVABLE_EVAL_STATUSES = ['NOT_STARTED', 'DRAFT'] as const

async function reassignDroppedJurorAssignments(params: {
  roundId: string
  droppedJurorId: string
  auditUserId?: string
  auditIp?: string
  auditUserAgent?: string
}) {
  const round = await prisma.round.findUnique({
    where: { id: params.roundId },
    select: { id: true, name: true, configJson: true, juryGroupId: true },
  })

  if (!round) {
    throw new TRPCError({ code: 'NOT_FOUND', message: 'Round not found' })
  }

  const droppedJuror = await prisma.user.findUnique({
    where: { id: params.droppedJurorId },
    select: { id: true, name: true, email: true },
  })

  if (!droppedJuror) {
    throw new TRPCError({ code: 'NOT_FOUND', message: 'Juror not found' })
  }

  const config = (round.configJson ?? {}) as Record<string, unknown>
  const fallbackCap =
    (config.maxLoadPerJuror as number) ??
    (config.maxAssignmentsPerJuror as number) ??
    20

  // Only pick assignments with no evaluation or evaluation still in draft/not-started.
  // Explicitly enumerate movable statuses so SUBMITTED and LOCKED are never touched.
  const assignmentsToMove = await prisma.assignment.findMany({
    where: {
      roundId: params.roundId,
      userId: params.droppedJurorId,
      OR: [
        { evaluation: null },
        { evaluation: { status: { in: [...MOVABLE_EVAL_STATUSES] } } },
      ],
    },
    select: {
      id: true,
      projectId: true,
      juryGroupId: true,
      isRequired: true,
      createdAt: true,
      project: { select: { title: true } },
    },
    orderBy: { createdAt: 'asc' },
  })

  if (assignmentsToMove.length === 0) {
    return {
      movedCount: 0,
      failedCount: 0,
      failedProjects: [] as string[],
      reassignedTo: {} as Record<string, number>,
    }
  }

  let candidateJurors: { id: string; name: string | null; email: string; maxAssignments: number | null }[]

  if (round.juryGroupId) {
    const members = await prisma.juryGroupMember.findMany({
      where: { juryGroupId: round.juryGroupId },
      include: {
        user: {
          select: {
            id: true,
            name: true,
            email: true,
            maxAssignments: true,
            status: true,
          },
        },
      },
    })

    candidateJurors = members
      .filter((m) => m.user.status === 'ACTIVE' && m.user.id !== params.droppedJurorId)
      .map((m) => m.user)
  } else {
    // No jury group configured — scope to jurors already assigned to this round
    // (the de facto jury pool). This prevents assigning to random JURY_MEMBER
    // accounts that aren't part of this round's jury.
    const roundJurorIds = await prisma.assignment.findMany({
      where: { roundId: params.roundId },
      select: { userId: true },
      distinct: ['userId'],
    })
    const activeRoundJurorIds = roundJurorIds
      .map((a) => a.userId)
      .filter((id) => id !== params.droppedJurorId)

    candidateJurors = activeRoundJurorIds.length > 0
      ? await prisma.user.findMany({
          where: {
            id: { in: activeRoundJurorIds },
            role: 'JURY_MEMBER',
            status: 'ACTIVE',
          },
          select: { id: true, name: true, email: true, maxAssignments: true },
        })
      : []
  }

  if (candidateJurors.length === 0) {
    throw new TRPCError({ code: 'BAD_REQUEST', message: 'No active replacement jurors available' })
  }

  const candidateIds = candidateJurors.map((j) => j.id)

  const existingAssignments = await prisma.assignment.findMany({
    where: { roundId: params.roundId },
    select: { userId: true, projectId: true },
  })

  const alreadyAssigned = new Set(existingAssignments.map((a) => `${a.userId}:${a.projectId}`))
  const currentLoads = new Map<string, number>()
  for (const a of existingAssignments) {
    currentLoads.set(a.userId, (currentLoads.get(a.userId) ?? 0) + 1)
  }

  const coiRecords = await prisma.conflictOfInterest.findMany({
    where: {
      roundId: params.roundId,
      hasConflict: true,
      userId: { in: candidateIds },
    },
    select: { userId: true, projectId: true },
  })
  const coiPairs = new Set(coiRecords.map((c) => `${c.userId}:${c.projectId}`))

  const caps = new Map<string, number>()
  for (const juror of candidateJurors) {
    caps.set(juror.id, juror.maxAssignments ?? fallbackCap)
  }

  const candidateMeta = new Map(candidateJurors.map((j) => [j.id, j]))
  const plannedMoves: {
    assignmentId: string
    projectId: string
    projectTitle: string
    newJurorId: string
    juryGroupId: string | null
    isRequired: boolean
  }[] = []
  const failedProjects: string[] = []

  for (const assignment of assignmentsToMove) {
    const eligible = candidateIds
      .filter((jurorId) => !alreadyAssigned.has(`${jurorId}:${assignment.projectId}`))
      .filter((jurorId) => !coiPairs.has(`${jurorId}:${assignment.projectId}`))
      .filter((jurorId) => (currentLoads.get(jurorId) ?? 0) < (caps.get(jurorId) ?? fallbackCap))
      .sort((a, b) => {
        const loadDiff = (currentLoads.get(a) ?? 0) - (currentLoads.get(b) ?? 0)
        if (loadDiff !== 0) return loadDiff
        return a.localeCompare(b)
      })

    if (eligible.length === 0) {
      failedProjects.push(assignment.project.title)
      continue
    }

    const selectedJurorId = eligible[0]
    plannedMoves.push({
      assignmentId: assignment.id,
      projectId: assignment.projectId,
      projectTitle: assignment.project.title,
      newJurorId: selectedJurorId,
      juryGroupId: assignment.juryGroupId ?? round.juryGroupId,
      isRequired: assignment.isRequired,
    })

    alreadyAssigned.add(`${selectedJurorId}:${assignment.projectId}`)
    currentLoads.set(selectedJurorId, (currentLoads.get(selectedJurorId) ?? 0) + 1)
  }

  // Execute moves inside a transaction with per-move TOCTOU guard.
  // Uses conditional deleteMany so a concurrent evaluation submission
  // (which sets status to SUBMITTED) causes the delete to return count=0
  // instead of cascade-destroying the submitted evaluation.
  const actualMoves: typeof plannedMoves = []
  const skippedProjects: string[] = []

  if (plannedMoves.length > 0) {
    await prisma.$transaction(async (tx) => {
      for (const move of plannedMoves) {
        // Guard: only delete if the assignment still belongs to the dropped juror
        // AND its evaluation (if any) is still in a movable state.
        // If a juror submitted between our read and now, count will be 0.
        const deleted = await tx.assignment.deleteMany({
          where: {
            id: move.assignmentId,
            userId: params.droppedJurorId,
            OR: [
              { evaluation: null },
              { evaluation: { status: { in: [...MOVABLE_EVAL_STATUSES] } } },
            ],
          },
        })

        if (deleted.count === 0) {
          // Assignment was already moved, deleted, or its evaluation was submitted
          skippedProjects.push(move.projectTitle)
          continue
        }

        await tx.assignment.create({
          data: {
            roundId: params.roundId,
            projectId: move.projectId,
            userId: move.newJurorId,
            juryGroupId: move.juryGroupId ?? undefined,
            isRequired: move.isRequired,
            method: 'MANUAL',
            createdBy: params.auditUserId ?? undefined,
          },
        })
        actualMoves.push(move)
      }
    })
  }

  // Add skipped projects to the failed list
  failedProjects.push(...skippedProjects)

  const reassignedTo: Record<string, number> = {}
  for (const move of actualMoves) {
    reassignedTo[move.newJurorId] = (reassignedTo[move.newJurorId] ?? 0) + 1
  }

  if (actualMoves.length > 0) {
    await createBulkNotifications({
      userIds: Object.keys(reassignedTo),
      type: NotificationTypes.BATCH_ASSIGNED,
      title: 'Additional Projects Assigned',
      message: `You have received additional project assignments due to a jury reassignment in ${round.name}.`,
      linkUrl: `/jury/competitions`,
      linkLabel: 'View Assignments',
      metadata: { roundId: round.id, reason: 'juror_drop_reshuffle' },
    })

    const droppedName = droppedJuror.name || droppedJuror.email
    const topReceivers = Object.entries(reassignedTo)
      .map(([jurorId, count]) => {
        const juror = candidateMeta.get(jurorId)
        return `${juror?.name || juror?.email || jurorId} (${count})`
      })
      .join(', ')

    await notifyAdmins({
      type: NotificationTypes.EVALUATION_MILESTONE,
      title: 'Juror Dropout Reshuffle',
      message: `Reassigned ${actualMoves.length} project(s) from ${droppedName} to: ${topReceivers}. ${failedProjects.length > 0 ? `${failedProjects.length} project(s) could not be reassigned.` : 'All projects were reassigned successfully.'}`,
      linkUrl: `/admin/rounds/${round.id}`,
      linkLabel: 'View Round',
      metadata: {
        roundId: round.id,
        droppedJurorId: droppedJuror.id,
        movedCount: actualMoves.length,
        failedCount: failedProjects.length,
        topReceivers,
      },
    })
  }

  // Remove the dropped juror from the jury group so they can't be re-assigned
  // in future assignment runs for this round's competition.
  let removedFromGroup = false
  if (round.juryGroupId) {
    const deleted = await prisma.juryGroupMember.deleteMany({
      where: {
        juryGroupId: round.juryGroupId,
        userId: params.droppedJurorId,
      },
    })
    removedFromGroup = deleted.count > 0
  }

  if (params.auditUserId) {
    // Build per-project move detail for audit trail
    const moveDetails = actualMoves.map((move) => {
      const juror = candidateMeta.get(move.newJurorId)
      return {
        projectId: move.projectId,
        projectTitle: move.projectTitle,
        newJurorId: move.newJurorId,
        newJurorName: juror?.name || juror?.email || move.newJurorId,
      }
    })

    await logAudit({
      prisma,
      userId: params.auditUserId,
      action: 'JUROR_DROPOUT_RESHUFFLE',
      entityType: 'Round',
      entityId: round.id,
      detailsJson: {
        droppedJurorId: droppedJuror.id,
        droppedJurorName: droppedJuror.name || droppedJuror.email,
        movedCount: actualMoves.length,
        failedCount: failedProjects.length,
        failedProjects,
        skippedProjects,
        reassignedTo,
        removedFromGroup,
        moves: moveDetails,
      },
      ipAddress: params.auditIp,
      userAgent: params.auditUserAgent,
    })
  }

  return {
    movedCount: actualMoves.length,
    failedCount: failedProjects.length,
    failedProjects,
    reassignedTo,
  }
}

async function runAIAssignmentJob(jobId: string, roundId: string, userId: string) {
  try {
    await prisma.assignmentJob.update({
      where: { id: jobId },
      data: { status: 'RUNNING', startedAt: new Date() },
    })

    const round = await prisma.round.findUniqueOrThrow({
      where: { id: roundId },
      select: {
        name: true,
        configJson: true,
        competitionId: true,
        juryGroupId: true,
      },
    })

    const config = (round.configJson ?? {}) as Record<string, unknown>
    const requiredReviews = (config.requiredReviewsPerProject as number) ?? 3
    const minAssignmentsPerJuror =
      (config.minLoadPerJuror as number) ??
      (config.minAssignmentsPerJuror as number) ??
      1
    const maxAssignmentsPerJuror =
      (config.maxLoadPerJuror as number) ??
      (config.maxAssignmentsPerJuror as number) ??
      20

    // Scope jurors to jury group if the round has one assigned
    let scopedJurorIds: string[] | undefined
    if (round.juryGroupId) {
      const groupMembers = await prisma.juryGroupMember.findMany({
        where: { juryGroupId: round.juryGroupId },
        select: { userId: true },
      })
      scopedJurorIds = groupMembers.map((m) => m.userId)
    }

    const jurors = await prisma.user.findMany({
      where: {
        role: 'JURY_MEMBER',
        status: 'ACTIVE',
        ...(scopedJurorIds ? { id: { in: scopedJurorIds } } : {}),
      },
      select: {
        id: true,
        name: true,
        email: true,
        expertiseTags: true,
        maxAssignments: true,
        _count: {
          select: {
            assignments: { where: { roundId } },
          },
        },
      },
    })

    const projectRoundStates = await prisma.projectRoundState.findMany({
      where: { roundId },
      select: { projectId: true },
    })
    const projectIds = projectRoundStates.map((prs) => prs.projectId)

    const projects = await prisma.project.findMany({
      where: { id: { in: projectIds } },
      select: {
        id: true,
        title: true,
        description: true,
        tags: true,
        teamName: true,
        projectTags: {
          select: { tag: { select: { name: true } }, confidence: true },
        },
        _count: { select: { assignments: { where: { roundId } } } },
      },
    })

    // Enrich projects with tag confidence data for AI matching
    const projectsWithConfidence = projects.map((p) => ({
      ...p,
      tagConfidences: p.projectTags.map((pt) => ({
        name: pt.tag.name,
        confidence: pt.confidence,
      })),
    }))

    const existingAssignments = await prisma.assignment.findMany({
      where: { roundId },
      select: { userId: true, projectId: true },
    })

    // Query COI records for this round to exclude conflicted juror-project pairs
    const coiRecords = await prisma.conflictOfInterest.findMany({
      where: {
        roundId,
        hasConflict: true,
      },
      select: { userId: true, projectId: true },
    })
    const coiExclusions = new Set(
      coiRecords.map((c) => `${c.userId}:${c.projectId}`)
    )

    // Calculate batch info
    const BATCH_SIZE = 15
    const totalBatches = Math.ceil(projects.length / BATCH_SIZE)

    await prisma.assignmentJob.update({
      where: { id: jobId },
      data: { totalProjects: projects.length, totalBatches },
    })

    // Progress callback
    const onProgress: AssignmentProgressCallback = async (progress) => {
      await prisma.assignmentJob.update({
        where: { id: jobId },
        data: {
          currentBatch: progress.currentBatch,
          processedCount: progress.processedCount,
        },
      })
    }

    // Build per-juror limits map for jurors with personal maxAssignments
    const jurorLimits: Record<string, number> = {}
    for (const juror of jurors) {
      if (juror.maxAssignments !== null && juror.maxAssignments !== undefined) {
        jurorLimits[juror.id] = juror.maxAssignments
      }
    }

    const constraints = {
      requiredReviewsPerProject: requiredReviews,
      minAssignmentsPerJuror,
      maxAssignmentsPerJuror,
      jurorLimits: Object.keys(jurorLimits).length > 0 ? jurorLimits : undefined,
      existingAssignments: existingAssignments.map((a) => ({
        jurorId: a.userId,
        projectId: a.projectId,
      })),
    }

    const result = await generateAIAssignments(
      jurors,
      projectsWithConfidence,
      constraints,
      userId,
      roundId,
      onProgress
    )

    // Filter out suggestions that conflict with COI declarations
    const filteredSuggestions = coiExclusions.size > 0
      ? result.suggestions.filter((s) => !coiExclusions.has(`${s.jurorId}:${s.projectId}`))
      : result.suggestions

    // Enrich suggestions with names for storage
    const enrichedSuggestions = filteredSuggestions.map((s) => {
      const juror = jurors.find((j) => j.id === s.jurorId)
      const project = projects.find((p) => p.id === s.projectId)
      return {
        ...s,
        jurorName: juror?.name || juror?.email || 'Unknown',
        projectTitle: project?.title || 'Unknown',
      }
    })

    // Mark job as completed and store suggestions
    await prisma.assignmentJob.update({
      where: { id: jobId },
      data: {
        status: 'COMPLETED',
        completedAt: new Date(),
        processedCount: projects.length,
        suggestionsCount: filteredSuggestions.length,
        suggestionsJson: enrichedSuggestions,
        fallbackUsed: result.fallbackUsed ?? false,
      },
    })

    await notifyAdmins({
      type: NotificationTypes.AI_SUGGESTIONS_READY,
      title: 'AI Assignment Suggestions Ready',
      message: `AI generated ${filteredSuggestions.length} assignment suggestions for ${round.name || 'round'}${result.fallbackUsed ? ' (using fallback algorithm)' : ''}.`,
      linkUrl: `/admin/rounds/${roundId}`,
      linkLabel: 'View Suggestions',
      priority: 'high',
      metadata: {
        roundId,
        jobId,
        projectCount: projects.length,
        suggestionsCount: filteredSuggestions.length,
        fallbackUsed: result.fallbackUsed,
      },
    })

  } catch (error) {
    console.error('[AI Assignment Job] Error:', error)

    // Mark job as failed
    await prisma.assignmentJob.update({
      where: { id: jobId },
      data: {
        status: 'FAILED',
        errorMessage: error instanceof Error ? error.message : 'Unknown error',
        completedAt: new Date(),
      },
    })
  }
}

export const assignmentRouter = router({
  listByStage: adminProcedure
    .input(z.object({ roundId: z.string() }))
    .query(async ({ ctx, input }) => {
      return ctx.prisma.assignment.findMany({
        where: { roundId: input.roundId },
        include: {
          user: { select: { id: true, name: true, email: true, expertiseTags: true } },
          project: { select: { id: true, title: true, tags: true } },
          evaluation: { select: { status: true, submittedAt: true } },
          conflictOfInterest: { select: { hasConflict: true, conflictType: true, reviewAction: true } },
        },
        orderBy: { createdAt: 'desc' },
      })
    }),

  /**
   * List assignments for a project (admin only)
   */
  listByProject: adminProcedure
    .input(z.object({ projectId: z.string() }))
    .query(async ({ ctx, input }) => {
      const assignments = await ctx.prisma.assignment.findMany({
        where: { projectId: input.projectId },
        include: {
          user: { select: { id: true, name: true, email: true, expertiseTags: true, profileImageKey: true, profileImageProvider: true } },
          evaluation: { select: { status: true, submittedAt: true, globalScore: true, binaryDecision: true } },
        },
        orderBy: { createdAt: 'desc' },
      })

      // Attach avatar URLs
      return Promise.all(
        assignments.map(async (a) => ({
          ...a,
          user: {
            ...a.user,
            avatarUrl: await getUserAvatarUrl(a.user.profileImageKey, a.user.profileImageProvider),
          },
        }))
      )
    }),

  /**
   * Get my assignments (for jury members)
   */
  myAssignments: protectedProcedure
    .input(
      z.object({
        roundId: z.string().optional(),
        status: z.enum(['all', 'pending', 'completed']).default('all'),
      })
    )
    .query(async ({ ctx, input }) => {
      const where: Record<string, unknown> = {
        userId: ctx.user.id,
      }

      if (input.roundId) {
        where.roundId = input.roundId
      }

      if (input.status === 'pending') {
        where.isCompleted = false
      } else if (input.status === 'completed') {
        where.isCompleted = true
      }

      return ctx.prisma.assignment.findMany({
        where,
        include: {
          project: {
            include: { files: true },
          },
          round: true,
          evaluation: true,
        },
        orderBy: [{ isCompleted: 'asc' }, { createdAt: 'asc' }],
      })
    }),

  /**
   * Get assignment by ID
   */
  get: protectedProcedure
    .input(z.object({ id: z.string() }))
    .query(async ({ ctx, input }) => {
      const assignment = await ctx.prisma.assignment.findUniqueOrThrow({
        where: { id: input.id },
        include: {
          user: { select: { id: true, name: true, email: true } },
          project: { include: { files: true } },
          round: { include: { evaluationForms: { where: { isActive: true } } } },
          evaluation: true,
        },
      })

      // Verify access
      if (
        ctx.user.role === 'JURY_MEMBER' &&
        assignment.userId !== ctx.user.id
      ) {
        throw new TRPCError({
          code: 'FORBIDDEN',
          message: 'You do not have access to this assignment',
        })
      }

      return assignment
    }),

  /**
   * Create a single assignment (admin only)
   */
  create: adminProcedure
    .input(
      z.object({
        userId: z.string(),
        projectId: z.string(),
        roundId: z.string(),
        isRequired: z.boolean().default(true),
        forceOverride: z.boolean().default(false),
      })
    )
    .mutation(async ({ ctx, input }) => {
      const existing = await ctx.prisma.assignment.findUnique({
        where: {
          userId_projectId_roundId: {
            userId: input.userId,
            projectId: input.projectId,
            roundId: input.roundId,
          },
        },
      })

      if (existing) {
        throw new TRPCError({
          code: 'CONFLICT',
          message: 'This assignment already exists',
        })
      }

      const [stage, user] = await Promise.all([
        ctx.prisma.round.findUniqueOrThrow({
          where: { id: input.roundId },
          select: { configJson: true },
        }),
        ctx.prisma.user.findUniqueOrThrow({
          where: { id: input.userId },
          select: { maxAssignments: true, name: true },
        }),
      ])

      const config = (stage.configJson ?? {}) as Record<string, unknown>
      const maxAssignmentsPerJuror =
        (config.maxLoadPerJuror as number) ??
        (config.maxAssignmentsPerJuror as number) ??
        20
      const effectiveMax = user.maxAssignments ?? maxAssignmentsPerJuror

      const currentCount = await ctx.prisma.assignment.count({
        where: { userId: input.userId, roundId: input.roundId },
      })

      // Check if at or over limit
      if (currentCount >= effectiveMax) {
        if (!input.forceOverride) {
          throw new TRPCError({
            code: 'BAD_REQUEST',
            message: `${user.name || 'Judge'} has reached their maximum limit of ${effectiveMax} projects. Use manual override to proceed.`,
          })
        }
        // Log the override in audit
        console.log(`[Assignment] Manual override: Assigning ${user.name} beyond limit (${currentCount}/${effectiveMax})`)
      }

      const { forceOverride: _override, ...assignmentData } = input
      const assignment = await ctx.prisma.assignment.create({
        data: {
          ...assignmentData,
          method: 'MANUAL',
          createdBy: ctx.user.id,
        },
      })

      // Audit log
      await logAudit({
        prisma: ctx.prisma,
        userId: ctx.user.id,
        action: 'CREATE',
        entityType: 'Assignment',
        entityId: assignment.id,
        detailsJson: input,
        ipAddress: ctx.ip,
        userAgent: ctx.userAgent,
      })

      const [project, stageInfo] = await Promise.all([
        ctx.prisma.project.findUnique({
          where: { id: input.projectId },
          select: { title: true },
        }),
        ctx.prisma.round.findUnique({
          where: { id: input.roundId },
          select: { name: true, windowCloseAt: true },
        }),
      ])

      if (project && stageInfo) {
        const deadline = stageInfo.windowCloseAt
          ? new Date(stageInfo.windowCloseAt).toLocaleDateString('en-US', {
              weekday: 'long',
              year: 'numeric',
              month: 'long',
              day: 'numeric',
            })
          : undefined

        await createNotification({
          userId: input.userId,
          type: NotificationTypes.ASSIGNED_TO_PROJECT,
          title: 'New Project Assignment',
          message: `You have been assigned to evaluate "${project.title}" for ${stageInfo.name}.`,
          linkUrl: `/jury/competitions`,
          linkLabel: 'View Assignment',
          metadata: {
            projectName: project.title,
            roundName: stageInfo.name,
            deadline,
            assignmentId: assignment.id,
          },
        })
      }

      return assignment
    }),

  /**
   * Bulk create assignments (admin only)
   */
  bulkCreate: adminProcedure
    .input(
      z.object({
        roundId: z.string(),
        assignments: z.array(
          z.object({
            userId: z.string(),
            projectId: z.string(),
          })
        ),
      })
    )
    .mutation(async ({ ctx, input }) => {
      // Fetch per-juror maxAssignments and current counts for capacity checking
      const uniqueUserIds = [...new Set(input.assignments.map((a) => a.userId))]
      const users = await ctx.prisma.user.findMany({
        where: { id: { in: uniqueUserIds } },
        select: {
          id: true,
          name: true,
          maxAssignments: true,
          _count: {
            select: {
              assignments: { where: { roundId: input.roundId } },
            },
          },
        },
      })
      const userMap = new Map(users.map((u) => [u.id, u]))

      // Get stage default max
      const stage = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.roundId },
        select: { configJson: true, name: true, windowCloseAt: true },
      })
      const config = (stage.configJson ?? {}) as Record<string, unknown>
      const stageMaxPerJuror =
        (config.maxLoadPerJuror as number) ??
        (config.maxAssignmentsPerJuror as number) ??
        20

      // Track running counts to handle multiple assignments to the same juror in one batch
      const runningCounts = new Map<string, number>()
      for (const u of users) {
        runningCounts.set(u.id, u._count.assignments)
      }

      // Filter out assignments that would exceed a juror's limit
      let skippedDueToCapacity = 0
      const allowedAssignments = input.assignments.filter((a) => {
        const user = userMap.get(a.userId)
        if (!user) return true // unknown user, let createMany handle it

        const effectiveMax = user.maxAssignments ?? stageMaxPerJuror
        const currentCount = runningCounts.get(a.userId) ?? 0

        if (currentCount >= effectiveMax) {
          skippedDueToCapacity++
          return false
        }

        // Increment running count for subsequent assignments to same user
        runningCounts.set(a.userId, currentCount + 1)
        return true
      })

      const result = await ctx.prisma.assignment.createMany({
        data: allowedAssignments.map((a) => ({
          ...a,
          roundId: input.roundId,
          method: 'BULK',
          createdBy: ctx.user.id,
        })),
        skipDuplicates: true,
      })

      // Audit log
      await logAudit({
        prisma: ctx.prisma,
        userId: ctx.user.id,
        action: 'BULK_CREATE',
        entityType: 'Assignment',
        detailsJson: {
          count: result.count,
          requested: input.assignments.length,
          skippedDueToCapacity,
        },
        ipAddress: ctx.ip,
        userAgent: ctx.userAgent,
      })

      // Send notifications to assigned jury members (grouped by user)
      if (result.count > 0 && allowedAssignments.length > 0) {
        // Group assignments by user to get counts
        const userAssignmentCounts = allowedAssignments.reduce(
          (acc, a) => {
            acc[a.userId] = (acc[a.userId] || 0) + 1
            return acc
          },
          {} as Record<string, number>
        )

        const deadline = stage?.windowCloseAt
          ? new Date(stage.windowCloseAt).toLocaleDateString('en-US', {
              weekday: 'long',
              year: 'numeric',
              month: 'long',
              day: 'numeric',
            })
          : undefined

        const usersByProjectCount = new Map<number, string[]>()
        for (const [userId, projectCount] of Object.entries(userAssignmentCounts)) {
          const existing = usersByProjectCount.get(projectCount) || []
          existing.push(userId)
          usersByProjectCount.set(projectCount, existing)
        }

        for (const [projectCount, userIds] of usersByProjectCount) {
          if (userIds.length === 0) continue
          await createBulkNotifications({
            userIds,
            type: NotificationTypes.BATCH_ASSIGNED,
            title: `${projectCount} Projects Assigned`,
            message: `You have been assigned ${projectCount} project${projectCount > 1 ? 's' : ''} to evaluate for ${stage?.name || 'this stage'}.`,
            linkUrl: `/jury/competitions`,
            linkLabel: 'View Assignments',
            metadata: {
              projectCount,
              roundName: stage?.name,
              deadline,
            },
          })
        }
      }

      return {
        created: result.count,
        requested: input.assignments.length,
        skipped: input.assignments.length - result.count,
        skippedDueToCapacity,
      }
    }),

  /**
   * Delete an assignment (admin only)
   */
  delete: adminProcedure
    .input(z.object({ id: z.string() }))
    .mutation(async ({ ctx, input }) => {
      const assignment = await ctx.prisma.assignment.delete({
        where: { id: input.id },
      })

      // Audit log
      await logAudit({
        prisma: ctx.prisma,
        userId: ctx.user.id,
        action: 'DELETE',
        entityType: 'Assignment',
        entityId: input.id,
        detailsJson: {
          userId: assignment.userId,
          projectId: assignment.projectId,
        },
        ipAddress: ctx.ip,
        userAgent: ctx.userAgent,
      })

      return assignment
    }),

  /**
   * Get assignment statistics for a round
   */
  getStats: adminProcedure
    .input(z.object({ roundId: z.string() }))
    .query(async ({ ctx, input }) => {
      const stage = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.roundId },
        select: { configJson: true },
      })
      const config = (stage.configJson ?? {}) as Record<string, unknown>
      const requiredReviews = (config.requiredReviewsPerProject as number) ?? 3

      const projectRoundStates = await ctx.prisma.projectRoundState.findMany({
        where: { roundId: input.roundId },
        select: { projectId: true },
      })
      const projectIds = projectRoundStates.map((pss) => pss.projectId)

      const [
        totalAssignments,
        completedAssignments,
        assignmentsByUser,
        projectCoverage,
      ] = await Promise.all([
        ctx.prisma.assignment.count({ where: { roundId: input.roundId } }),
        ctx.prisma.assignment.count({
          where: { roundId: input.roundId, isCompleted: true },
        }),
        ctx.prisma.assignment.groupBy({
          by: ['userId'],
          where: { roundId: input.roundId },
          _count: true,
        }),
        ctx.prisma.project.findMany({
          where: { id: { in: projectIds } },
          select: {
            id: true,
            title: true,
            _count: { select: { assignments: { where: { roundId: input.roundId } } } },
          },
        }),
      ])

      const projectsWithFullCoverage = projectCoverage.filter(
        (p) => p._count.assignments >= requiredReviews
      ).length

      return {
        totalAssignments,
        completedAssignments,
        completionPercentage:
          totalAssignments > 0
            ? Math.round((completedAssignments / totalAssignments) * 100)
            : 0,
        juryMembersAssigned: assignmentsByUser.length,
        projectsWithFullCoverage,
        totalProjects: projectCoverage.length,
        coveragePercentage:
          projectCoverage.length > 0
            ? Math.round(
                (projectsWithFullCoverage / projectCoverage.length) * 100
              )
            : 0,
      }
    }),

  /**
   * Get smart assignment suggestions using algorithm
   */
  getSuggestions: adminProcedure
    .input(
      z.object({
        roundId: z.string(),
      })
    )
    .query(async ({ ctx, input }) => {
      const stage = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.roundId },
        select: { configJson: true, juryGroupId: true },
      })
      const config = (stage.configJson ?? {}) as Record<string, unknown>
      const requiredReviews = (config.requiredReviewsPerProject as number) ?? 3
      const minAssignmentsPerJuror =
        (config.minLoadPerJuror as number) ??
        (config.minAssignmentsPerJuror as number) ??
        1
      const maxAssignmentsPerJuror =
        (config.maxLoadPerJuror as number) ??
        (config.maxAssignmentsPerJuror as number) ??
        20

      // Extract category quotas if enabled
      const categoryQuotasEnabled = config.categoryQuotasEnabled === true
      const categoryQuotas = categoryQuotasEnabled
        ? (config.categoryQuotas as Record<string, { min: number; max: number }> | undefined)
        : undefined

      // Scope jurors to jury group if the round has one assigned
      let scopedJurorIds: string[] | undefined
      if (stage.juryGroupId) {
        const groupMembers = await ctx.prisma.juryGroupMember.findMany({
          where: { juryGroupId: stage.juryGroupId },
          select: { userId: true },
        })
        scopedJurorIds = groupMembers.map((m) => m.userId)
      }

      const jurors = await ctx.prisma.user.findMany({
        where: {
          role: 'JURY_MEMBER',
          status: 'ACTIVE',
          ...(scopedJurorIds ? { id: { in: scopedJurorIds } } : {}),
        },
        select: {
          id: true,
          name: true,
          email: true,
          expertiseTags: true,
          maxAssignments: true,
          _count: {
            select: {
              assignments: { where: { roundId: input.roundId } },
            },
          },
        },
      })

      const projectRoundStates = await ctx.prisma.projectRoundState.findMany({
        where: { roundId: input.roundId },
        select: { projectId: true },
      })
      const projectIds = projectRoundStates.map((pss) => pss.projectId)

      const projects = await ctx.prisma.project.findMany({
        where: { id: { in: projectIds } },
        select: {
          id: true,
          title: true,
          tags: true,
          competitionCategory: true,
          projectTags: {
            include: { tag: { select: { name: true } } },
          },
          _count: { select: { assignments: { where: { roundId: input.roundId } } } },
        },
      })

      const existingAssignments = await ctx.prisma.assignment.findMany({
        where: { roundId: input.roundId },
        select: { userId: true, projectId: true },
      })
      const assignmentSet = new Set(
        existingAssignments.map((a) => `${a.userId}-${a.projectId}`)
      )

      // Build per-juror category distribution for quota scoring
      const jurorCategoryDistribution = new Map<string, Record<string, number>>()
      if (categoryQuotas) {
        const assignmentsWithCategory = await ctx.prisma.assignment.findMany({
          where: { roundId: input.roundId },
          select: {
            userId: true,
            project: { select: { competitionCategory: true } },
          },
        })
        for (const a of assignmentsWithCategory) {
          const cat = a.project.competitionCategory?.toLowerCase().trim()
          if (!cat) continue
          let catMap = jurorCategoryDistribution.get(a.userId)
          if (!catMap) {
            catMap = {}
            jurorCategoryDistribution.set(a.userId, catMap)
          }
          catMap[cat] = (catMap[cat] || 0) + 1
        }
      }

      const suggestions: Array<{
        userId: string
        jurorName: string
        projectId: string
        projectTitle: string
        score: number
        reasoning: string[]
      }> = []

      for (const project of projects) {
        if (project._count.assignments >= requiredReviews) continue

        const neededAssignments = requiredReviews - project._count.assignments

        const jurorScores = jurors
          .filter((j) => {
            if (assignmentSet.has(`${j.id}-${project.id}`)) return false
            const effectiveMax = j.maxAssignments ?? maxAssignmentsPerJuror
            if (j._count.assignments >= effectiveMax) return false
            return true
          })
          .map((juror) => {
            const reasoning: string[] = []
            let score = 0

            const projectTagNames = project.projectTags.map((pt) => pt.tag.name.toLowerCase())

            const matchingTags = projectTagNames.length > 0
              ? juror.expertiseTags.filter((tag) =>
                  projectTagNames.includes(tag.toLowerCase())
                )
              : juror.expertiseTags.filter((tag) =>
                  project.tags.map((t) => t.toLowerCase()).includes(tag.toLowerCase())
                )

            const totalTags = projectTagNames.length > 0 ? projectTagNames.length : project.tags.length
            const expertiseScore =
              matchingTags.length > 0
                ? matchingTags.length / Math.max(totalTags, 1)
                : 0
            score += expertiseScore * 35
            if (matchingTags.length > 0) {
              reasoning.push(`Expertise match: ${matchingTags.join(', ')}`)
            }

            const effectiveMax = juror.maxAssignments ?? maxAssignmentsPerJuror
            const loadScore = 1 - juror._count.assignments / effectiveMax
            score += loadScore * 20

            const underMinBonus =
              juror._count.assignments < minAssignmentsPerJuror
                ? (minAssignmentsPerJuror - juror._count.assignments) * 3
                : 0
            score += Math.min(15, underMinBonus)

            if (juror._count.assignments < minAssignmentsPerJuror) {
              reasoning.push(
                `Under target: ${juror._count.assignments}/${minAssignmentsPerJuror} min`
              )
            }
            reasoning.push(
              `Capacity: ${juror._count.assignments}/${effectiveMax} max`
            )

            // Category quota scoring
            if (categoryQuotas) {
              const jurorCategoryCounts = jurorCategoryDistribution.get(juror.id) || {}
              const normalizedCat = project.competitionCategory?.toLowerCase().trim()
              if (normalizedCat) {
                const quota = Object.entries(categoryQuotas).find(
                  ([key]) => key.toLowerCase().trim() === normalizedCat
                )
                if (quota) {
                  const [, { min, max }] = quota
                  const currentCount = jurorCategoryCounts[normalizedCat] || 0
                  if (currentCount >= max) {
                    score -= 25
                    reasoning.push(`Category quota exceeded (-25)`)
                  } else if (currentCount < min) {
                    const otherAboveMin = Object.entries(categoryQuotas).some(([key, q]) => {
                      if (key.toLowerCase().trim() === normalizedCat) return false
                      return (jurorCategoryCounts[key.toLowerCase().trim()] || 0) >= q.min
                    })
                    if (otherAboveMin) {
                      score += 10
                      reasoning.push(`Category quota bonus (+10)`)
                    }
                  }
                }
              }
            }

            return {
              userId: juror.id,
              jurorName: juror.name || juror.email || 'Unknown',
              projectId: project.id,
              projectTitle: project.title || 'Unknown',
              score,
              reasoning,
            }
          })
          .sort((a, b) => b.score - a.score)
          .slice(0, neededAssignments)

        suggestions.push(...jurorScores)
      }

      return suggestions.sort((a, b) => b.score - a.score)
    }),

  /**
   * Check if AI assignment is available
   */
  isAIAvailable: adminProcedure.query(async () => {
    return isOpenAIConfigured()
  }),

  /**
   * Get AI-powered assignment suggestions (retrieves from completed job)
   */
  getAISuggestions: adminProcedure
    .input(
      z.object({
        roundId: z.string(),
        useAI: z.boolean().default(true),
      })
    )
    .query(async ({ ctx, input }) => {
      const completedJob = await ctx.prisma.assignmentJob.findFirst({
        where: {
          roundId: input.roundId,
          status: 'COMPLETED',
        },
        orderBy: { completedAt: 'desc' },
        select: {
          suggestionsJson: true,
          fallbackUsed: true,
          completedAt: true,
        },
      })

      if (completedJob?.suggestionsJson) {
        const suggestions = completedJob.suggestionsJson as Array<{
          jurorId: string
          jurorName: string
          projectId: string
          projectTitle: string
          confidenceScore: number
          expertiseMatchScore: number
          reasoning: string
        }>

        const existingAssignments = await ctx.prisma.assignment.findMany({
          where: { roundId: input.roundId },
          select: { userId: true, projectId: true },
        })
        const assignmentSet = new Set(
          existingAssignments.map((a) => `${a.userId}-${a.projectId}`)
        )

        const filteredSuggestions = suggestions.filter(
          (s) => !assignmentSet.has(`${s.jurorId}-${s.projectId}`)
        )

        return {
          success: true,
          suggestions: filteredSuggestions,
          fallbackUsed: completedJob.fallbackUsed,
          error: null,
          generatedAt: completedJob.completedAt,
        }
      }

      return {
        success: true,
        suggestions: [],
        fallbackUsed: false,
        error: null,
        generatedAt: null,
      }
    }),

  /**
   * Apply AI-suggested assignments
   */
  applyAISuggestions: adminProcedure
    .input(
      z.object({
        roundId: z.string(),
        assignments: z.array(
          z.object({
            userId: z.string(),
            projectId: z.string(),
            confidenceScore: z.number().optional(),
            expertiseMatchScore: z.number().optional(),
            reasoning: z.string().optional(),
          })
        ),
        usedAI: z.boolean().default(false),
        forceOverride: z.boolean().default(false),
      })
    )
    .mutation(async ({ ctx, input }) => {
      let assignmentsToCreate = input.assignments
      let skippedDueToCapacity = 0

      // Capacity check (unless forceOverride)
      if (!input.forceOverride) {
        const uniqueUserIds = [...new Set(input.assignments.map((a) => a.userId))]
        const users = await ctx.prisma.user.findMany({
          where: { id: { in: uniqueUserIds } },
          select: {
            id: true,
            maxAssignments: true,
            _count: {
              select: {
                assignments: { where: { roundId: input.roundId } },
              },
            },
          },
        })
        const userMap = new Map(users.map((u) => [u.id, u]))

        const stageData = await ctx.prisma.round.findUniqueOrThrow({
          where: { id: input.roundId },
          select: { configJson: true },
        })
        const config = (stageData.configJson ?? {}) as Record<string, unknown>
        const stageMaxPerJuror =
          (config.maxLoadPerJuror as number) ??
          (config.maxAssignmentsPerJuror as number) ??
          20

        const runningCounts = new Map<string, number>()
        for (const u of users) {
          runningCounts.set(u.id, u._count.assignments)
        }

        assignmentsToCreate = input.assignments.filter((a) => {
          const user = userMap.get(a.userId)
          if (!user) return true

          const effectiveMax = user.maxAssignments ?? stageMaxPerJuror
          const currentCount = runningCounts.get(a.userId) ?? 0

          if (currentCount >= effectiveMax) {
            skippedDueToCapacity++
            return false
          }

          runningCounts.set(a.userId, currentCount + 1)
          return true
        })
      }

      const created = await ctx.prisma.assignment.createMany({
        data: assignmentsToCreate.map((a) => ({
          userId: a.userId,
          projectId: a.projectId,
          roundId: input.roundId,
          method: input.usedAI ? 'AI_SUGGESTED' : 'ALGORITHM',
          aiConfidenceScore: a.confidenceScore,
          expertiseMatchScore: a.expertiseMatchScore,
          aiReasoning: a.reasoning,
          createdBy: ctx.user.id,
        })),
        skipDuplicates: true,
      })

      await logAudit({
        prisma: ctx.prisma,
        userId: ctx.user.id,
        action: input.usedAI ? 'APPLY_AI_SUGGESTIONS' : 'APPLY_SUGGESTIONS',
        entityType: 'Assignment',
        detailsJson: {
          roundId: input.roundId,
          count: created.count,
          usedAI: input.usedAI,
          forceOverride: input.forceOverride,
          skippedDueToCapacity,
        },
        ipAddress: ctx.ip,
        userAgent: ctx.userAgent,
      })

      if (created.count > 0) {
        const userAssignmentCounts = assignmentsToCreate.reduce(
          (acc, a) => {
            acc[a.userId] = (acc[a.userId] || 0) + 1
            return acc
          },
          {} as Record<string, number>
        )

        const stage = await ctx.prisma.round.findUnique({
          where: { id: input.roundId },
          select: { name: true, windowCloseAt: true },
        })

        const deadline = stage?.windowCloseAt
          ? new Date(stage.windowCloseAt).toLocaleDateString('en-US', {
              weekday: 'long',
              year: 'numeric',
              month: 'long',
              day: 'numeric',
            })
          : undefined

        const usersByProjectCount = new Map<number, string[]>()
        for (const [userId, projectCount] of Object.entries(userAssignmentCounts)) {
          const existing = usersByProjectCount.get(projectCount) || []
          existing.push(userId)
          usersByProjectCount.set(projectCount, existing)
        }

        for (const [projectCount, userIds] of usersByProjectCount) {
          if (userIds.length === 0) continue
          await createBulkNotifications({
            userIds,
            type: NotificationTypes.BATCH_ASSIGNED,
            title: `${projectCount} Projects Assigned`,
            message: `You have been assigned ${projectCount} project${projectCount > 1 ? 's' : ''} to evaluate for ${stage?.name || 'this stage'}.`,
            linkUrl: `/jury/competitions`,
            linkLabel: 'View Assignments',
            metadata: {
              projectCount,
              roundName: stage?.name,
              deadline,
            },
          })
        }
      }

      return {
        created: created.count,
        requested: input.assignments.length,
        skippedDueToCapacity,
      }
    }),

  /**
   * Apply suggested assignments
   */
  applySuggestions: adminProcedure
    .input(
      z.object({
        roundId: z.string(),
        assignments: z.array(
          z.object({
            userId: z.string(),
            projectId: z.string(),
            reasoning: z.string().optional(),
          })
        ),
        forceOverride: z.boolean().default(false),
      })
    )
    .mutation(async ({ ctx, input }) => {
      let assignmentsToCreate = input.assignments
      let skippedDueToCapacity = 0

      // Capacity check (unless forceOverride)
      if (!input.forceOverride) {
        const uniqueUserIds = [...new Set(input.assignments.map((a) => a.userId))]
        const users = await ctx.prisma.user.findMany({
          where: { id: { in: uniqueUserIds } },
          select: {
            id: true,
            maxAssignments: true,
            _count: {
              select: {
                assignments: { where: { roundId: input.roundId } },
              },
            },
          },
        })
        const userMap = new Map(users.map((u) => [u.id, u]))

        const stageData = await ctx.prisma.round.findUniqueOrThrow({
          where: { id: input.roundId },
          select: { configJson: true },
        })
        const config = (stageData.configJson ?? {}) as Record<string, unknown>
        const stageMaxPerJuror =
          (config.maxLoadPerJuror as number) ??
          (config.maxAssignmentsPerJuror as number) ??
          20

        const runningCounts = new Map<string, number>()
        for (const u of users) {
          runningCounts.set(u.id, u._count.assignments)
        }

        assignmentsToCreate = input.assignments.filter((a) => {
          const user = userMap.get(a.userId)
          if (!user) return true

          const effectiveMax = user.maxAssignments ?? stageMaxPerJuror
          const currentCount = runningCounts.get(a.userId) ?? 0

          if (currentCount >= effectiveMax) {
            skippedDueToCapacity++
            return false
          }

          runningCounts.set(a.userId, currentCount + 1)
          return true
        })
      }

      const created = await ctx.prisma.assignment.createMany({
        data: assignmentsToCreate.map((a) => ({
          userId: a.userId,
          projectId: a.projectId,
          roundId: input.roundId,
          method: 'ALGORITHM',
          aiReasoning: a.reasoning,
          createdBy: ctx.user.id,
        })),
        skipDuplicates: true,
      })

      await logAudit({
        prisma: ctx.prisma,
        userId: ctx.user.id,
        action: 'APPLY_SUGGESTIONS',
        entityType: 'Assignment',
        detailsJson: {
          roundId: input.roundId,
          count: created.count,
          forceOverride: input.forceOverride,
          skippedDueToCapacity,
        },
        ipAddress: ctx.ip,
        userAgent: ctx.userAgent,
      })

      if (created.count > 0) {
        const userAssignmentCounts = assignmentsToCreate.reduce(
          (acc, a) => {
            acc[a.userId] = (acc[a.userId] || 0) + 1
            return acc
          },
          {} as Record<string, number>
        )

        const stage = await ctx.prisma.round.findUnique({
          where: { id: input.roundId },
          select: { name: true, windowCloseAt: true },
        })

        const deadline = stage?.windowCloseAt
          ? new Date(stage.windowCloseAt).toLocaleDateString('en-US', {
              weekday: 'long',
              year: 'numeric',
              month: 'long',
              day: 'numeric',
            })
          : undefined

        const usersByProjectCount = new Map<number, string[]>()
        for (const [userId, projectCount] of Object.entries(userAssignmentCounts)) {
          const existing = usersByProjectCount.get(projectCount) || []
          existing.push(userId)
          usersByProjectCount.set(projectCount, existing)
        }

        for (const [projectCount, userIds] of usersByProjectCount) {
          if (userIds.length === 0) continue
          await createBulkNotifications({
            userIds,
            type: NotificationTypes.BATCH_ASSIGNED,
            title: `${projectCount} Projects Assigned`,
            message: `You have been assigned ${projectCount} project${projectCount > 1 ? 's' : ''} to evaluate for ${stage?.name || 'this stage'}.`,
            linkUrl: `/jury/competitions`,
            linkLabel: 'View Assignments',
            metadata: {
              projectCount,
              roundName: stage?.name,
              deadline,
            },
          })
        }
      }

      return {
        created: created.count,
        requested: input.assignments.length,
        skippedDueToCapacity,
      }
    }),

  /**
   * Start an AI assignment job (background processing)
   */
  startAIAssignmentJob: adminProcedure
    .input(z.object({ roundId: z.string() }))
    .mutation(async ({ ctx, input }) => {
      const existingJob = await ctx.prisma.assignmentJob.findFirst({
        where: {
          roundId: input.roundId,
          status: { in: ['PENDING', 'RUNNING'] },
        },
      })

      if (existingJob) {
        throw new TRPCError({
          code: 'BAD_REQUEST',
          message: 'An AI assignment job is already running for this stage',
        })
      }

      if (!isOpenAIConfigured()) {
        throw new TRPCError({
          code: 'BAD_REQUEST',
          message: 'OpenAI API is not configured',
        })
      }

      const job = await ctx.prisma.assignmentJob.create({
        data: {
          roundId: input.roundId,
          status: 'PENDING',
        },
      })

      runAIAssignmentJob(job.id, input.roundId, ctx.user.id).catch(console.error)

      return { jobId: job.id }
    }),

  /**
   * Get AI assignment job status (for polling)
   */
  getAIAssignmentJobStatus: adminProcedure
    .input(z.object({ jobId: z.string() }))
    .query(async ({ ctx, input }) => {
      const job = await ctx.prisma.assignmentJob.findUniqueOrThrow({
        where: { id: input.jobId },
      })

      return {
        id: job.id,
        status: job.status,
        totalProjects: job.totalProjects,
        totalBatches: job.totalBatches,
        currentBatch: job.currentBatch,
        processedCount: job.processedCount,
        suggestionsCount: job.suggestionsCount,
        fallbackUsed: job.fallbackUsed,
        errorMessage: job.errorMessage,
        startedAt: job.startedAt,
        completedAt: job.completedAt,
      }
    }),

  /**
   * Get the latest AI assignment job for a round
   */
  getLatestAIAssignmentJob: adminProcedure
    .input(z.object({ roundId: z.string() }))
    .query(async ({ ctx, input }) => {
      const job = await ctx.prisma.assignmentJob.findFirst({
        where: { roundId: input.roundId },
        orderBy: { createdAt: 'desc' },
      })

      if (!job) return null

      return {
        id: job.id,
        status: job.status,
        totalProjects: job.totalProjects,
        totalBatches: job.totalBatches,
        currentBatch: job.currentBatch,
        processedCount: job.processedCount,
        suggestionsCount: job.suggestionsCount,
        fallbackUsed: job.fallbackUsed,
        errorMessage: job.errorMessage,
        startedAt: job.startedAt,
        completedAt: job.completedAt,
        createdAt: job.createdAt,
      }
    }),

  /**
   * Notify all jurors of their current assignments for a round (admin only).
   * Sends in-app notifications (emails are handled by maybeSendEmail via createBulkNotifications).
   */
  notifyJurorsOfAssignments: adminProcedure
    .input(z.object({ roundId: z.string() }))
    .mutation(async ({ ctx, input }) => {
      const round = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.roundId },
        select: { name: true, windowCloseAt: true },
      })

      // Get all assignments grouped by user
      const assignments = await ctx.prisma.assignment.findMany({
        where: { roundId: input.roundId },
        select: { userId: true },
      })

      if (assignments.length === 0) {
        return { sent: 0, jurorCount: 0 }
      }

      // Count assignments per user
      const userCounts: Record<string, number> = {}
      for (const a of assignments) {
        userCounts[a.userId] = (userCounts[a.userId] || 0) + 1
      }

      const deadline = round.windowCloseAt
        ? new Date(round.windowCloseAt).toLocaleDateString('en-US', {
            weekday: 'long',
            year: 'numeric',
            month: 'long',
            day: 'numeric',
          })
        : undefined

      // Create in-app notifications grouped by project count
      const usersByProjectCount = new Map<number, string[]>()
      for (const [userId, projectCount] of Object.entries(userCounts)) {
        const existing = usersByProjectCount.get(projectCount) || []
        existing.push(userId)
        usersByProjectCount.set(projectCount, existing)
      }

      let totalSent = 0
      for (const [projectCount, userIds] of usersByProjectCount) {
        if (userIds.length === 0) continue
        await createBulkNotifications({
          userIds,
          type: NotificationTypes.BATCH_ASSIGNED,
          title: `${projectCount} Projects Assigned`,
          message: `You have been assigned ${projectCount} project${projectCount > 1 ? 's' : ''} to evaluate for ${round.name || 'this round'}.`,
          linkUrl: `/jury/competitions`,
          linkLabel: 'View Assignments',
          metadata: { projectCount, roundName: round.name, deadline },
        })
        totalSent += userIds.length
      }

      await logAudit({
        prisma: ctx.prisma,
        userId: ctx.user.id,
        action: 'NOTIFY_JURORS_OF_ASSIGNMENTS',
        entityType: 'Round',
        entityId: input.roundId,
        detailsJson: {
          jurorCount: Object.keys(userCounts).length,
          totalAssignments: assignments.length,
        },
        ipAddress: ctx.ip,
        userAgent: ctx.userAgent,
      })

      return { sent: totalSent, jurorCount: Object.keys(userCounts).length }
    }),

  notifySingleJurorOfAssignments: adminProcedure
    .input(z.object({ roundId: z.string(), userId: z.string() }))
    .mutation(async ({ ctx, input }) => {
      const round = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.roundId },
        select: { name: true, windowCloseAt: true },
      })

      const assignments = await ctx.prisma.assignment.findMany({
        where: { roundId: input.roundId, userId: input.userId },
        select: { id: true },
      })

      if (assignments.length === 0) {
        throw new TRPCError({ code: 'NOT_FOUND', message: 'No assignments found for this juror in this round' })
      }

      const projectCount = assignments.length
      const deadline = round.windowCloseAt
        ? new Date(round.windowCloseAt).toLocaleDateString('en-US', {
            weekday: 'long',
            year: 'numeric',
            month: 'long',
            day: 'numeric',
          })
        : undefined

      await createBulkNotifications({
        userIds: [input.userId],
        type: NotificationTypes.BATCH_ASSIGNED,
        title: `${projectCount} Projects Assigned`,
        message: `You have been assigned ${projectCount} project${projectCount > 1 ? 's' : ''} to evaluate for ${round.name || 'this round'}.`,
        linkUrl: `/jury/competitions`,
        linkLabel: 'View Assignments',
        metadata: { projectCount, roundName: round.name, deadline },
      })

      await logAudit({
        prisma: ctx.prisma,
        userId: ctx.user.id,
        action: 'NOTIFY_SINGLE_JUROR_OF_ASSIGNMENTS',
        entityType: 'Round',
        entityId: input.roundId,
        detailsJson: {
          targetUserId: input.userId,
          assignmentCount: projectCount,
        },
        ipAddress: ctx.ip,
        userAgent: ctx.userAgent,
      })

      return { sent: 1, projectCount }
    }),

  reassignCOI: adminProcedure
    .input(z.object({ assignmentId: z.string() }))
    .mutation(async ({ ctx, input }) => {
      const result = await reassignAfterCOI({
        assignmentId: input.assignmentId,
        auditUserId: ctx.user.id,
        auditIp: ctx.ip,
        auditUserAgent: ctx.userAgent,
      })

      if (!result) {
        throw new TRPCError({
          code: 'BAD_REQUEST',
          message: 'No eligible juror found for reassignment. All jurors are either already assigned to this project, have a COI, or are at their assignment limit.',
        })
      }

      return result
    }),

  reassignDroppedJuror: adminProcedure
    .input(z.object({ roundId: z.string(), jurorId: z.string() }))
    .mutation(async ({ ctx, input }) => {
      return reassignDroppedJurorAssignments({
        roundId: input.roundId,
        droppedJurorId: input.jurorId,
        auditUserId: ctx.user.id,
        auditIp: ctx.ip,
        auditUserAgent: ctx.userAgent,
      })
    }),

  /**
   * Get transfer candidates: which of the source juror's assignments can be moved,
   * and which other jurors are eligible to receive them.
   */
  getTransferCandidates: adminProcedure
    .input(z.object({
      roundId: z.string(),
      sourceJurorId: z.string(),
      assignmentIds: z.array(z.string()),
    }))
    .query(async ({ ctx, input }) => {
      const round = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.roundId },
        select: { id: true, name: true, configJson: true, juryGroupId: true },
      })

      const config = (round.configJson ?? {}) as Record<string, unknown>
      const fallbackCap =
        (config.maxLoadPerJuror as number) ??
        (config.maxAssignmentsPerJuror as number) ??
        20

      // Fetch requested assignments — must belong to source juror
      const requestedAssignments = await ctx.prisma.assignment.findMany({
        where: {
          id: { in: input.assignmentIds },
          roundId: input.roundId,
          userId: input.sourceJurorId,
        },
        select: {
          id: true,
          projectId: true,
          project: { select: { title: true } },
          evaluation: { select: { status: true } },
        },
      })

      // Filter to movable only
      const assignments = requestedAssignments.map((a) => ({
        id: a.id,
        projectId: a.projectId,
        projectTitle: a.project.title,
        evalStatus: a.evaluation?.status ?? null,
        movable: !a.evaluation || MOVABLE_EVAL_STATUSES.includes(a.evaluation.status as typeof MOVABLE_EVAL_STATUSES[number]),
      }))

      const movableProjectIds = assignments
        .filter((a) => a.movable)
        .map((a) => a.projectId)

      // Build candidate juror pool — same pattern as reassignDroppedJurorAssignments
      let candidateJurors: { id: string; name: string | null; email: string; maxAssignments: number | null }[]

      if (round.juryGroupId) {
        const members = await ctx.prisma.juryGroupMember.findMany({
          where: { juryGroupId: round.juryGroupId },
          include: {
            user: { select: { id: true, name: true, email: true, maxAssignments: true, status: true } },
          },
        })
        candidateJurors = members
          .filter((m) => m.user.status === 'ACTIVE' && m.user.id !== input.sourceJurorId)
          .map((m) => m.user)
      } else {
        const roundJurorIds = await ctx.prisma.assignment.findMany({
          where: { roundId: input.roundId },
          select: { userId: true },
          distinct: ['userId'],
        })
        const activeRoundJurorIds = roundJurorIds
          .map((a) => a.userId)
          .filter((id) => id !== input.sourceJurorId)

        candidateJurors = activeRoundJurorIds.length > 0
          ? await ctx.prisma.user.findMany({
              where: {
                id: { in: activeRoundJurorIds },
                role: 'JURY_MEMBER',
                status: 'ACTIVE',
              },
              select: { id: true, name: true, email: true, maxAssignments: true },
            })
          : []
      }

      const candidateIds = candidateJurors.map((j) => j.id)

      // Existing assignments, loads, COI pairs
      const existingAssignments = await ctx.prisma.assignment.findMany({
        where: { roundId: input.roundId },
        select: { userId: true, projectId: true },
      })

      const currentLoads = new Map<string, number>()
      for (const a of existingAssignments) {
        currentLoads.set(a.userId, (currentLoads.get(a.userId) ?? 0) + 1)
      }

      const alreadyAssigned = new Set(existingAssignments.map((a) => `${a.userId}:${a.projectId}`))

      // Completed evaluations count per candidate
      const completedEvals = await ctx.prisma.evaluation.findMany({
        where: {
          assignment: { roundId: input.roundId, userId: { in: candidateIds } },
          status: 'SUBMITTED',
        },
        select: { assignment: { select: { userId: true } } },
      })
      const completedCounts = new Map<string, number>()
      for (const e of completedEvals) {
        const uid = e.assignment.userId
        completedCounts.set(uid, (completedCounts.get(uid) ?? 0) + 1)
      }

      const coiRecords = await ctx.prisma.conflictOfInterest.findMany({
        where: {
          roundId: input.roundId,
          hasConflict: true,
          userId: { in: candidateIds },
        },
        select: { userId: true, projectId: true },
      })
      const coiPairs = new Set(coiRecords.map((c) => `${c.userId}:${c.projectId}`))

      // Build candidate list with eligibility per project
      const candidates = candidateJurors.map((j) => {
        const load = currentLoads.get(j.id) ?? 0
        const cap = j.maxAssignments ?? fallbackCap
        const completed = completedCounts.get(j.id) ?? 0
        const allCompleted = load > 0 && completed === load

        const eligibleProjectIds = movableProjectIds.filter((pid) =>
          !alreadyAssigned.has(`${j.id}:${pid}`) &&
          !coiPairs.has(`${j.id}:${pid}`) &&
          load < cap
        )

        return {
          userId: j.id,
          name: j.name || j.email,
          email: j.email,
          currentLoad: load,
          cap,
          allCompleted,
          eligibleProjectIds,
        }
      })

      // Sort: not-all-done first, then by lowest load
      candidates.sort((a, b) => {
        if (a.allCompleted !== b.allCompleted) return a.allCompleted ? 1 : -1
        return a.currentLoad - b.currentLoad
      })

      return { assignments, candidates }
    }),

  /**
   * Transfer specific assignments from one juror to destination jurors.
   */
  transferAssignments: adminProcedure
    .input(z.object({
      roundId: z.string(),
      sourceJurorId: z.string(),
      transfers: z.array(z.object({
        assignmentId: z.string(),
        destinationJurorId: z.string(),
      })),
      forceOverCap: z.boolean().default(false),
    }))
    .mutation(async ({ ctx, input }) => {
      const round = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.roundId },
        select: { id: true, name: true, configJson: true, juryGroupId: true },
      })

      const config = (round.configJson ?? {}) as Record<string, unknown>
      const fallbackCap =
        (config.maxLoadPerJuror as number) ??
        (config.maxAssignmentsPerJuror as number) ??
        20

      // Verify all assignments belong to source juror and are movable
      const assignmentIds = input.transfers.map((t) => t.assignmentId)
      const sourceAssignments = await ctx.prisma.assignment.findMany({
        where: {
          id: { in: assignmentIds },
          roundId: input.roundId,
          userId: input.sourceJurorId,
          OR: [
            { evaluation: null },
            { evaluation: { status: { in: [...MOVABLE_EVAL_STATUSES] } } },
          ],
        },
        select: {
          id: true,
          projectId: true,
          juryGroupId: true,
          isRequired: true,
          project: { select: { title: true } },
        },
      })

      const sourceMap = new Map(sourceAssignments.map((a) => [a.id, a]))

      // Build candidate pool data
      const destinationIds = [...new Set(input.transfers.map((t) => t.destinationJurorId))]
      const destinationUsers = await ctx.prisma.user.findMany({
        where: { id: { in: destinationIds } },
        select: { id: true, name: true, email: true, maxAssignments: true },
      })
      const destUserMap = new Map(destinationUsers.map((u) => [u.id, u]))

      const existingAssignments = await ctx.prisma.assignment.findMany({
        where: { roundId: input.roundId },
        select: { userId: true, projectId: true },
      })
      const alreadyAssigned = new Set(existingAssignments.map((a) => `${a.userId}:${a.projectId}`))
      const currentLoads = new Map<string, number>()
      for (const a of existingAssignments) {
        currentLoads.set(a.userId, (currentLoads.get(a.userId) ?? 0) + 1)
      }

      const coiRecords = await ctx.prisma.conflictOfInterest.findMany({
        where: {
          roundId: input.roundId,
          hasConflict: true,
          userId: { in: destinationIds },
        },
        select: { userId: true, projectId: true },
      })
      const coiPairs = new Set(coiRecords.map((c) => `${c.userId}:${c.projectId}`))

      // Validate each transfer
      type PlannedMove = {
        assignmentId: string
        projectId: string
        projectTitle: string
        destinationJurorId: string
        juryGroupId: string | null
        isRequired: boolean
      }
      const plannedMoves: PlannedMove[] = []
      const failed: { assignmentId: string; reason: string }[] = []

      for (const transfer of input.transfers) {
        const assignment = sourceMap.get(transfer.assignmentId)
        if (!assignment) {
          failed.push({ assignmentId: transfer.assignmentId, reason: 'Assignment not found or not movable' })
          continue
        }

        const destUser = destUserMap.get(transfer.destinationJurorId)
        if (!destUser) {
          failed.push({ assignmentId: transfer.assignmentId, reason: 'Destination juror not found' })
          continue
        }

        if (alreadyAssigned.has(`${transfer.destinationJurorId}:${assignment.projectId}`)) {
          failed.push({ assignmentId: transfer.assignmentId, reason: `${destUser.name || destUser.email} is already assigned to this project` })
          continue
        }

        if (coiPairs.has(`${transfer.destinationJurorId}:${assignment.projectId}`)) {
          failed.push({ assignmentId: transfer.assignmentId, reason: `${destUser.name || destUser.email} has a COI with this project` })
          continue
        }

        const destCap = destUser.maxAssignments ?? fallbackCap
        const destLoad = currentLoads.get(transfer.destinationJurorId) ?? 0
        if (destLoad >= destCap && !input.forceOverCap) {
          failed.push({ assignmentId: transfer.assignmentId, reason: `${destUser.name || destUser.email} is at cap (${destLoad}/${destCap})` })
          continue
        }

        plannedMoves.push({
          assignmentId: assignment.id,
          projectId: assignment.projectId,
          projectTitle: assignment.project.title,
          destinationJurorId: transfer.destinationJurorId,
          juryGroupId: assignment.juryGroupId ?? round.juryGroupId,
          isRequired: assignment.isRequired,
        })

        // Track updated load for subsequent transfers to same destination
        alreadyAssigned.add(`${transfer.destinationJurorId}:${assignment.projectId}`)
        currentLoads.set(transfer.destinationJurorId, destLoad + 1)
      }

      // Execute in transaction with TOCTOU guard
      const actualMoves: (PlannedMove & { newAssignmentId: string })[] = []

      if (plannedMoves.length > 0) {
        await ctx.prisma.$transaction(async (tx) => {
          for (const move of plannedMoves) {
            const deleted = await tx.assignment.deleteMany({
              where: {
                id: move.assignmentId,
                userId: input.sourceJurorId,
                OR: [
                  { evaluation: null },
                  { evaluation: { status: { in: [...MOVABLE_EVAL_STATUSES] } } },
                ],
              },
            })

            if (deleted.count === 0) {
              failed.push({ assignmentId: move.assignmentId, reason: 'Assignment was modified concurrently' })
              continue
            }

            const created = await tx.assignment.create({
              data: {
                roundId: input.roundId,
                projectId: move.projectId,
                userId: move.destinationJurorId,
                juryGroupId: move.juryGroupId ?? undefined,
                isRequired: move.isRequired,
                method: 'MANUAL',
                createdBy: ctx.user.id,
              },
            })

            actualMoves.push({ ...move, newAssignmentId: created.id })
          }
        })
      }

      // Notify destination jurors
      if (actualMoves.length > 0) {
        const destCounts: Record<string, number> = {}
        for (const move of actualMoves) {
          destCounts[move.destinationJurorId] = (destCounts[move.destinationJurorId] ?? 0) + 1
        }

        await createBulkNotifications({
          userIds: Object.keys(destCounts),
          type: NotificationTypes.BATCH_ASSIGNED,
          title: 'Additional Projects Assigned',
          message: `You have received additional project assignments via transfer in ${round.name}.`,
          linkUrl: `/jury/competitions`,
          linkLabel: 'View Assignments',
          metadata: { roundId: round.id, reason: 'assignment_transfer' },
        })

        // Notify admins
        const sourceJuror = await ctx.prisma.user.findUnique({
          where: { id: input.sourceJurorId },
          select: { name: true, email: true },
        })
        const sourceName = sourceJuror?.name || sourceJuror?.email || 'Unknown'

        const topReceivers = Object.entries(destCounts)
          .map(([jurorId, count]) => {
            const u = destUserMap.get(jurorId)
            return `${u?.name || u?.email || jurorId} (${count})`
          })
          .join(', ')

        await notifyAdmins({
          type: NotificationTypes.EVALUATION_MILESTONE,
          title: 'Assignment Transfer',
          message: `Transferred ${actualMoves.length} project(s) from ${sourceName} to: ${topReceivers}.${failed.length > 0 ? ` ${failed.length} transfer(s) failed.` : ''}`,
          linkUrl: `/admin/rounds/${round.id}`,
          linkLabel: 'View Round',
          metadata: {
            roundId: round.id,
            sourceJurorId: input.sourceJurorId,
            movedCount: actualMoves.length,
            failedCount: failed.length,
          },
        })

        // Audit
        await logAudit({
          prisma: ctx.prisma,
          userId: ctx.user.id,
          action: 'ASSIGNMENT_TRANSFER',
          entityType: 'Round',
          entityId: round.id,
          detailsJson: {
            sourceJurorId: input.sourceJurorId,
            sourceJurorName: sourceName,
            movedCount: actualMoves.length,
            failedCount: failed.length,
            moves: actualMoves.map((m) => ({
              projectId: m.projectId,
              projectTitle: m.projectTitle,
              newJurorId: m.destinationJurorId,
              newJurorName: destUserMap.get(m.destinationJurorId)?.name || destUserMap.get(m.destinationJurorId)?.email || m.destinationJurorId,
            })),
          },
          ipAddress: ctx.ip,
          userAgent: ctx.userAgent,
        })
      }

      return {
        succeeded: actualMoves.map((m) => ({
          assignmentId: m.assignmentId,
          projectId: m.projectId,
          destinationJurorId: m.destinationJurorId,
        })),
        failed,
      }
    }),

  /**
   * Preview the impact of lowering a juror's cap below their current load.
   */
  getOverCapPreview: adminProcedure
    .input(z.object({
      roundId: z.string(),
      jurorId: z.string(),
      newCap: z.number().int().min(1),
    }))
    .query(async ({ ctx, input }) => {
      const total = await ctx.prisma.assignment.count({
        where: { roundId: input.roundId, userId: input.jurorId },
      })

      const immovableCount = await ctx.prisma.assignment.count({
        where: {
          roundId: input.roundId,
          userId: input.jurorId,
          evaluation: { status: { notIn: [...MOVABLE_EVAL_STATUSES] } },
        },
      })

      const movableCount = total - immovableCount
      const overCapCount = Math.max(0, total - input.newCap)

      return {
        total,
        overCapCount,
        movableOverCap: Math.min(overCapCount, movableCount),
        immovableOverCap: Math.max(0, overCapCount - movableCount),
      }
    }),

  /**
   * Redistribute over-cap assignments after lowering a juror's cap.
   * Moves the newest/least-progressed movable assignments to other eligible jurors.
   */
  redistributeOverCap: adminProcedure
    .input(z.object({
      roundId: z.string(),
      jurorId: z.string(),
      newCap: z.number().int().min(1),
    }))
    .mutation(async ({ ctx, input }) => {
      const round = await ctx.prisma.round.findUniqueOrThrow({
        where: { id: input.roundId },
        select: { id: true, name: true, configJson: true, juryGroupId: true },
      })

      const config = (round.configJson ?? {}) as Record<string, unknown>
      const fallbackCap =
        (config.maxLoadPerJuror as number) ??
        (config.maxAssignmentsPerJuror as number) ??
        20

      // Get juror's assignments sorted: null eval first, then DRAFT, newest first
      const jurorAssignments = await ctx.prisma.assignment.findMany({
        where: { roundId: input.roundId, userId: input.jurorId },
        select: {
          id: true,
          projectId: true,
          juryGroupId: true,
          isRequired: true,
          createdAt: true,
          project: { select: { title: true } },
          evaluation: { select: { status: true } },
        },
        orderBy: { createdAt: 'desc' },
      })

      const overCapCount = Math.max(0, jurorAssignments.length - input.newCap)
      if (overCapCount === 0) {
        return { redistributed: 0, failed: 0, failedProjects: [] as string[], moves: [] as { projectId: string; projectTitle: string; newJurorId: string; newJurorName: string }[] }
      }

      // Separate movable and immovable, pick the newest movable ones for redistribution
      const movable = jurorAssignments.filter(
        (a) => !a.evaluation || MOVABLE_EVAL_STATUSES.includes(a.evaluation.status as typeof MOVABLE_EVAL_STATUSES[number])
      )

      // Sort movable: null eval first, then DRAFT, then by createdAt descending (newest first to remove)
      movable.sort((a, b) => {
        const statusOrder = (s: string | null) => s === null ? 0 : s === 'NOT_STARTED' ? 1 : s === 'DRAFT' ? 2 : 3
        const diff = statusOrder(a.evaluation?.status ?? null) - statusOrder(b.evaluation?.status ?? null)
        if (diff !== 0) return diff
        return b.createdAt.getTime() - a.createdAt.getTime()
      })

      const assignmentsToMove = movable.slice(0, overCapCount)

      if (assignmentsToMove.length === 0) {
        return { redistributed: 0, failed: 0, failedProjects: [] as string[], moves: [] as { projectId: string; projectTitle: string; newJurorId: string; newJurorName: string }[] }
      }

      // Build candidate pool — same pattern as reassignDroppedJurorAssignments
      let candidateJurors: { id: string; name: string | null; email: string; maxAssignments: number | null }[]

      if (round.juryGroupId) {
        const members = await ctx.prisma.juryGroupMember.findMany({
          where: { juryGroupId: round.juryGroupId },
          include: {
            user: { select: { id: true, name: true, email: true, maxAssignments: true, status: true } },
          },
        })
        candidateJurors = members
          .filter((m) => m.user.status === 'ACTIVE' && m.user.id !== input.jurorId)
          .map((m) => m.user)
      } else {
        const roundJurorIds = await ctx.prisma.assignment.findMany({
          where: { roundId: input.roundId },
          select: { userId: true },
          distinct: ['userId'],
        })
        const activeRoundJurorIds = roundJurorIds
          .map((a) => a.userId)
          .filter((id) => id !== input.jurorId)

        candidateJurors = activeRoundJurorIds.length > 0
          ? await ctx.prisma.user.findMany({
              where: {
                id: { in: activeRoundJurorIds },
                role: 'JURY_MEMBER',
                status: 'ACTIVE',
              },
              select: { id: true, name: true, email: true, maxAssignments: true },
            })
          : []
      }

      if (candidateJurors.length === 0) {
        return {
          redistributed: 0,
          failed: assignmentsToMove.length,
          failedProjects: assignmentsToMove.map((a) => a.project.title),
          moves: [] as { projectId: string; projectTitle: string; newJurorId: string; newJurorName: string }[],
        }
      }

      const candidateIds = candidateJurors.map((j) => j.id)

      const existingAssignments = await ctx.prisma.assignment.findMany({
        where: { roundId: input.roundId },
        select: { userId: true, projectId: true },
      })

      const alreadyAssigned = new Set(existingAssignments.map((a) => `${a.userId}:${a.projectId}`))
      const currentLoads = new Map<string, number>()
      for (const a of existingAssignments) {
        currentLoads.set(a.userId, (currentLoads.get(a.userId) ?? 0) + 1)
      }

      const coiRecords = await ctx.prisma.conflictOfInterest.findMany({
        where: {
          roundId: input.roundId,
          hasConflict: true,
          userId: { in: candidateIds },
        },
        select: { userId: true, projectId: true },
      })
      const coiPairs = new Set(coiRecords.map((c) => `${c.userId}:${c.projectId}`))

      const caps = new Map<string, number>()
      for (const juror of candidateJurors) {
        caps.set(juror.id, juror.maxAssignments ?? fallbackCap)
      }

      // Check which candidates have completed all their evaluations
      const completedEvals = await ctx.prisma.evaluation.findMany({
        where: {
          assignment: { roundId: input.roundId, userId: { in: candidateIds } },
          status: 'SUBMITTED',
        },
        select: { assignment: { select: { userId: true } } },
      })
      const completedCounts = new Map<string, number>()
      for (const e of completedEvals) {
        completedCounts.set(e.assignment.userId, (completedCounts.get(e.assignment.userId) ?? 0) + 1)
      }

      const candidateMeta = new Map(candidateJurors.map((j) => [j.id, j]))

      type PlannedMove = {
        assignmentId: string
        projectId: string
        projectTitle: string
        newJurorId: string
        juryGroupId: string | null
        isRequired: boolean
      }
      const plannedMoves: PlannedMove[] = []
      const failedProjects: string[] = []

      for (const assignment of assignmentsToMove) {
        const eligible = candidateIds
          .filter((jurorId) => !alreadyAssigned.has(`${jurorId}:${assignment.projectId}`))
          .filter((jurorId) => !coiPairs.has(`${jurorId}:${assignment.projectId}`))
          .filter((jurorId) => (currentLoads.get(jurorId) ?? 0) < (caps.get(jurorId) ?? fallbackCap))
          .sort((a, b) => {
            // Prefer jurors who haven't completed all their work
            const aLoad = currentLoads.get(a) ?? 0
            const bLoad = currentLoads.get(b) ?? 0
            const aComplete = aLoad > 0 && (completedCounts.get(a) ?? 0) === aLoad
            const bComplete = bLoad > 0 && (completedCounts.get(b) ?? 0) === bLoad
            if (aComplete !== bComplete) return aComplete ? 1 : -1
            const loadDiff = aLoad - bLoad
            if (loadDiff !== 0) return loadDiff
            return a.localeCompare(b)
          })

        if (eligible.length === 0) {
          failedProjects.push(assignment.project.title)
          continue
        }

        const selectedJurorId = eligible[0]
        plannedMoves.push({
          assignmentId: assignment.id,
          projectId: assignment.projectId,
          projectTitle: assignment.project.title,
          newJurorId: selectedJurorId,
          juryGroupId: assignment.juryGroupId ?? round.juryGroupId,
          isRequired: assignment.isRequired,
        })

        alreadyAssigned.add(`${selectedJurorId}:${assignment.projectId}`)
        currentLoads.set(selectedJurorId, (currentLoads.get(selectedJurorId) ?? 0) + 1)
      }

      // Execute in transaction with TOCTOU guard
      const actualMoves: PlannedMove[] = []

      if (plannedMoves.length > 0) {
        await ctx.prisma.$transaction(async (tx) => {
          for (const move of plannedMoves) {
            const deleted = await tx.assignment.deleteMany({
              where: {
                id: move.assignmentId,
                userId: input.jurorId,
                OR: [
                  { evaluation: null },
                  { evaluation: { status: { in: [...MOVABLE_EVAL_STATUSES] } } },
                ],
              },
            })

            if (deleted.count === 0) {
              failedProjects.push(move.projectTitle)
              continue
            }

            await tx.assignment.create({
              data: {
                roundId: input.roundId,
                projectId: move.projectId,
                userId: move.newJurorId,
                juryGroupId: move.juryGroupId ?? undefined,
                isRequired: move.isRequired,
                method: 'MANUAL',
                createdBy: ctx.user.id,
              },
            })
            actualMoves.push(move)
          }
        })
      }

      // Notify destination jurors
      if (actualMoves.length > 0) {
        const destCounts: Record<string, number> = {}
        for (const move of actualMoves) {
          destCounts[move.newJurorId] = (destCounts[move.newJurorId] ?? 0) + 1
        }

        await createBulkNotifications({
          userIds: Object.keys(destCounts),
          type: NotificationTypes.BATCH_ASSIGNED,
          title: 'Additional Projects Assigned',
          message: `You have received additional project assignments due to a cap adjustment in ${round.name}.`,
          linkUrl: `/jury/competitions`,
          linkLabel: 'View Assignments',
          metadata: { roundId: round.id, reason: 'cap_redistribute' },
        })

        const juror = await ctx.prisma.user.findUnique({
          where: { id: input.jurorId },
          select: { name: true, email: true },
        })
        const jurorName = juror?.name || juror?.email || 'Unknown'

        const topReceivers = Object.entries(destCounts)
          .map(([jurorId, count]) => {
            const u = candidateMeta.get(jurorId)
            return `${u?.name || u?.email || jurorId} (${count})`
          })
          .join(', ')

        await notifyAdmins({
          type: NotificationTypes.EVALUATION_MILESTONE,
          title: 'Cap Redistribution',
          message: `Redistributed ${actualMoves.length} project(s) from ${jurorName} (cap lowered to ${input.newCap}) to: ${topReceivers}.${failedProjects.length > 0 ? ` ${failedProjects.length} project(s) could not be reassigned.` : ''}`,
          linkUrl: `/admin/rounds/${round.id}`,
          linkLabel: 'View Round',
          metadata: {
            roundId: round.id,
            jurorId: input.jurorId,
            newCap: input.newCap,
            movedCount: actualMoves.length,
            failedCount: failedProjects.length,
          },
        })

        await logAudit({
          prisma: ctx.prisma,
          userId: ctx.user.id,
          action: 'CAP_REDISTRIBUTE',
          entityType: 'Round',
          entityId: round.id,
          detailsJson: {
            jurorId: input.jurorId,
            jurorName,
            newCap: input.newCap,
            movedCount: actualMoves.length,
            failedCount: failedProjects.length,
            failedProjects,
            moves: actualMoves.map((m) => ({
              projectId: m.projectId,
              projectTitle: m.projectTitle,
              newJurorId: m.newJurorId,
              newJurorName: candidateMeta.get(m.newJurorId)?.name || candidateMeta.get(m.newJurorId)?.email || m.newJurorId,
            })),
          },
          ipAddress: ctx.ip,
          userAgent: ctx.userAgent,
        })
      }

      return {
        redistributed: actualMoves.length,
        failed: failedProjects.length,
        failedProjects,
        moves: actualMoves.map((m) => ({
          projectId: m.projectId,
          projectTitle: m.projectTitle,
          newJurorId: m.newJurorId,
          newJurorName: candidateMeta.get(m.newJurorId)?.name || candidateMeta.get(m.newJurorId)?.email || m.newJurorId,
        })),
      }
    }),

  /**
   * Get reshuffle history for a round — shows all dropout/COI reassignment events
   * with per-project detail of where each project was moved to.
   */
  getReassignmentHistory: adminProcedure
    .input(z.object({ roundId: z.string() }))
    .query(async ({ ctx, input }) => {
      // Get all reshuffle + COI audit entries for this round
      const auditEntries = await ctx.prisma.auditLog.findMany({
        where: {
          entityType: { in: ['Round', 'Assignment'] },
          action: { in: ['JUROR_DROPOUT_RESHUFFLE', 'COI_REASSIGNMENT', 'ASSIGNMENT_TRANSFER', 'CAP_REDISTRIBUTE'] },
          entityId: input.roundId,
        },
        orderBy: { timestamp: 'desc' },
        include: {
          user: { select: { id: true, name: true, email: true } },
        },
      })

      // Also get COI reassignment entries that reference this round in detailsJson
      const coiEntries = await ctx.prisma.auditLog.findMany({
        where: {
          action: 'COI_REASSIGNMENT',
          entityType: 'Assignment',
        },
        orderBy: { timestamp: 'desc' },
        include: {
          user: { select: { id: true, name: true, email: true } },
        },
      })

      // Filter COI entries to this round
      const coiForRound = coiEntries.filter((e) => {
        const details = e.detailsJson as Record<string, unknown> | null
        return details?.roundId === input.roundId
      })

      // For retroactive data: find all MANUAL assignments created in this round
      // that were created by an admin (not the juror themselves)
      const manualAssignments = await ctx.prisma.assignment.findMany({
        where: {
          roundId: input.roundId,
          method: 'MANUAL',
          createdBy: { not: null },
        },
        include: {
          user: { select: { id: true, name: true, email: true } },
          project: { select: { id: true, title: true } },
        },
        orderBy: { createdAt: 'desc' },
      })

      type ReshuffleEvent = {
        id: string
        type: 'DROPOUT' | 'COI' | 'TRANSFER' | 'CAP_REDISTRIBUTE'
        timestamp: Date
        performedBy: { name: string | null; email: string }
        droppedJuror: { id: string; name: string }
        movedCount: number
        failedCount: number
        failedProjects: string[]
        moves: { projectId: string; projectTitle: string; newJurorId: string; newJurorName: string }[]
      }

      const events: ReshuffleEvent[] = []

      for (const entry of auditEntries) {
        const details = entry.detailsJson as Record<string, unknown> | null
        if (!details) continue

        if (entry.action === 'JUROR_DROPOUT_RESHUFFLE') {
          // Check if this entry already has per-move detail (new format)
          const moves = (details.moves as { projectId: string; projectTitle: string; newJurorId: string; newJurorName: string }[]) || []

          // If no moves in audit (old format), reconstruct from assignments
          let reconstructedMoves = moves
          if (moves.length === 0 && (details.movedCount as number) > 0) {
            // Find MANUAL assignments created around the same time (within 5 seconds)
            const eventTime = entry.timestamp.getTime()
            reconstructedMoves = manualAssignments
              .filter((a) => {
                const diff = Math.abs(a.createdAt.getTime() - eventTime)
                return diff < 5000 && a.createdBy === entry.userId
              })
              .map((a) => ({
                projectId: a.project.id,
                projectTitle: a.project.title,
                newJurorId: a.user.id,
                newJurorName: a.user.name || a.user.email,
              }))
          }

          events.push({
            id: entry.id,
            type: 'DROPOUT',
            timestamp: entry.timestamp,
            performedBy: {
              name: entry.user?.name ?? null,
              email: entry.user?.email ?? '',
            },
            droppedJuror: {
              id: details.droppedJurorId as string,
              name: (details.droppedJurorName as string) || 'Unknown',
            },
            movedCount: (details.movedCount as number) || 0,
            failedCount: (details.failedCount as number) || 0,
            failedProjects: (details.failedProjects as string[]) || [],
            moves: reconstructedMoves,
          })
        } else if (entry.action === 'ASSIGNMENT_TRANSFER') {
          const moves = (details.moves as { projectId: string; projectTitle: string; newJurorId: string; newJurorName: string }[]) || []
          events.push({
            id: entry.id,
            type: 'TRANSFER',
            timestamp: entry.timestamp,
            performedBy: {
              name: entry.user?.name ?? null,
              email: entry.user?.email ?? '',
            },
            droppedJuror: {
              id: (details.sourceJurorId as string) || '',
              name: (details.sourceJurorName as string) || 'Unknown',
            },
            movedCount: (details.movedCount as number) || 0,
            failedCount: (details.failedCount as number) || 0,
            failedProjects: (details.failedProjects as string[]) || [],
            moves,
          })
        } else if (entry.action === 'CAP_REDISTRIBUTE') {
          const moves = (details.moves as { projectId: string; projectTitle: string; newJurorId: string; newJurorName: string }[]) || []
          events.push({
            id: entry.id,
            type: 'CAP_REDISTRIBUTE',
            timestamp: entry.timestamp,
            performedBy: {
              name: entry.user?.name ?? null,
              email: entry.user?.email ?? '',
            },
            droppedJuror: {
              id: (details.jurorId as string) || '',
              name: (details.jurorName as string) || 'Unknown',
            },
            movedCount: (details.movedCount as number) || 0,
            failedCount: (details.failedCount as number) || 0,
            failedProjects: (details.failedProjects as string[]) || [],
            moves,
          })
        }
      }

      // Process COI entries
      for (const entry of coiForRound) {
        const details = entry.detailsJson as Record<string, unknown> | null
        if (!details) continue

        // Look up project title
        const project = details.projectId
          ? await ctx.prisma.project.findUnique({
              where: { id: details.projectId as string },
              select: { title: true },
            })
          : null

        // Look up new juror name
        const newJuror = details.newJurorId
          ? await ctx.prisma.user.findUnique({
              where: { id: details.newJurorId as string },
              select: { name: true, email: true },
            })
          : null

        // Look up old juror name
        const oldJuror = details.oldJurorId
          ? await ctx.prisma.user.findUnique({
              where: { id: details.oldJurorId as string },
              select: { name: true, email: true },
            })
          : null

        events.push({
          id: entry.id,
          type: 'COI',
          timestamp: entry.timestamp,
          performedBy: {
            name: entry.user?.name ?? null,
            email: entry.user?.email ?? '',
          },
          droppedJuror: {
            id: (details.oldJurorId as string) || '',
            name: oldJuror?.name || oldJuror?.email || 'Unknown',
          },
          movedCount: 1,
          failedCount: 0,
          failedProjects: [],
          moves: [{
            projectId: (details.projectId as string) || '',
            projectTitle: project?.title || 'Unknown',
            newJurorId: (details.newJurorId as string) || '',
            newJurorName: newJuror?.name || newJuror?.email || 'Unknown',
          }],
        })
      }

      // Sort all events by timestamp descending
      events.sort((a, b) => b.timestamp.getTime() - a.timestamp.getTime())

      return events
    }),
})