'use client'

import { useState } from 'react'
import { trpc } from '@/lib/trpc/client'
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card'
import { Button } from '@/components/ui/button'
import { Badge } from '@/components/ui/badge'
import { Skeleton } from '@/components/ui/skeleton'
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from '@/components/ui/select'
import { FileText, Upload, CheckCircle2, ArrowUp } from 'lucide-react'
import { toast } from 'sonner'

interface FilePromotionPanelProps {
  mentorAssignmentId: string
}

function formatFileSize(bytes: number): string {
  if (bytes === 0) return '0 B'
  const k = 1024
  const sizes = ['B', 'KB', 'MB', 'GB']
  const i = Math.floor(Math.log(bytes) / Math.log(k))
  return parseFloat((bytes / Math.pow(k, i)).toFixed(2)) + ' ' + sizes[i]
}

export function FilePromotionPanel({ mentorAssignmentId }: FilePromotionPanelProps) {
  const [selectedSlot, setSelectedSlot] = useState<string>('')
  const utils = trpc.useUtils()

  const { data: workspaceFiles = [], isLoading: filesLoading } =
    trpc.mentor.workspaceGetFiles.useQuery(
      { mentorAssignmentId },
      { enabled: !!mentorAssignmentId },
    )

  const promoteMutation = trpc.mentor.workspacePromoteFile.useMutation({
    onSuccess: () => {
      toast.success('File promoted successfully')
      setSelectedSlot('')
    },
    onError: (err) => toast.error(err.message),
  })

  const handlePromote = (mentorFileId: string) => {
    if (!selectedSlot) {
      toast.error('Please select a file requirement slot')
      return
    }

    promoteMutation.mutate({
      roundId: '', // Would need to get this from context
      mentorFileId,
      slotKey: selectedSlot,
    })
  }

  const isLoading = filesLoading

  if (isLoading) {
    return (
      <Card>
        <CardHeader>
          <Skeleton className="h-6 w-48" />
        </CardHeader>
        <CardContent>
          <div className="space-y-4">
            {[1, 2, 3].map((i) => (
              <Skeleton key={i} className="h-20" />
            ))}
          </div>
        </CardContent>
      </Card>
    )
  }

  return (
    <Card>
      <CardHeader>
        <CardTitle className="flex items-center gap-2">
          <Upload className="h-5 w-5" />
          File Promotion
        </CardTitle>
        <CardDescription>
          Promote workspace files to official submission windows
        </CardDescription>
      </CardHeader>
      <CardContent>
        {/* Slot selector */}
        <div className="mb-6">
          <label className="text-sm font-medium mb-2 block">
            Target File Requirement
          </label>
          <Select value={selectedSlot} onValueChange={setSelectedSlot}>
            <SelectTrigger>
              <SelectValue placeholder="Select a file requirement..." />
            </SelectTrigger>
            <SelectContent>
              {/* Mock slots - in real implementation, would fetch available requirements */}
              <SelectItem value="pitch_deck">Pitch Deck</SelectItem>
              <SelectItem value="business_plan">Business Plan</SelectItem>
              <SelectItem value="presentation">Presentation</SelectItem>
            </SelectContent>
          </Select>
          <p className="text-xs text-muted-foreground mt-1">
            Select which file requirement to promote files to
          </p>
        </div>

        {/* Workspace files list */}
        <div className="space-y-3">
          {workspaceFiles.length === 0 ? (
            <div className="text-center py-12 border border-dashed rounded-lg">
              <FileText className="h-12 w-12 text-muted-foreground/50 mx-auto mb-3" />
              <p className="text-sm text-muted-foreground">No workspace files available</p>
              <p className="text-xs text-muted-foreground mt-1">
                Files shared in the workspace will appear here
              </p>
            </div>
          ) : (
            workspaceFiles.map((file: any) => {
              const isPromoted = file.promotedToWindow

              return (
                <Card key={file.id}>
                  <CardContent className="p-4">
                    <div className="flex items-start gap-4">
                      <div className="rounded-lg bg-brand-blue/10 p-3 shrink-0">
                        <FileText className="h-5 w-5 text-brand-blue" />
                      </div>
                      <div className="flex-1 min-w-0">
                        <div className="flex items-start justify-between gap-2 mb-2">
                          <div className="flex-1 min-w-0">
                            <p className="font-medium text-sm truncate" title={file.filename}>
                              {file.filename}
                            </p>
                            <div className="flex items-center gap-2 mt-1">
                              <Badge variant="outline" className="text-xs">
                                {file.mimeType?.split('/')[1]?.toUpperCase() || 'FILE'}
                              </Badge>
                              {file.size && (
                                <span className="text-xs text-muted-foreground">
                                  {formatFileSize(file.size)}
                                </span>
                              )}
                            </div>
                          </div>
                          {isPromoted ? (
                            <Badge variant="default" className="shrink-0 bg-emerald-50 text-emerald-700 border-emerald-200">
                              <CheckCircle2 className="mr-1 h-3 w-3" />
                              Promoted
                            </Badge>
                          ) : (
                            <Button
                              size="sm"
                              onClick={() => handlePromote(file.id)}
                              disabled={!selectedSlot || promoteMutation.isPending}
                              className="shrink-0"
                            >
                              <ArrowUp className="mr-1 h-3 w-3" />
                              Promote
                            </Button>
                          )}
                        </div>
                        {isPromoted && file.promotedToWindow && (
                          <p className="text-xs text-muted-foreground">
                            Promoted to: {file.promotedToWindow.name}
                          </p>
                        )}
                      </div>
                    </div>
                  </CardContent>
                </Card>
              )
            })
          )}
        </div>

        {workspaceFiles.length > 0 && (
          <div className="mt-4 p-3 bg-muted/50 rounded-lg">
            <p className="text-sm text-muted-foreground">
              <strong>Note:</strong> Promoting a file will make it visible to jurors in the selected
              submission window. This action can help teams submit refined versions of their work.
            </p>
          </div>
        )}
      </CardContent>
    </Card>
  )
}