import { useEffect, useState } from 'react'
import { useParams, useNavigate } from 'react-router-dom'
import { Copy, Check, Eye, Save } from 'lucide-react'
import { sessionsApi, stepsApi } from '@/api'
import { ExportPreviewModal } from '@/components/session/ExportPreviewModal'
import { SaveSessionAsTreeModal } from '@/components/session/SaveSessionAsTreeModal'
import { StepRatingModal } from '@/components/session/StepRatingModal'
import { useUserPreferencesStore } from '@/store/userPreferencesStore'
import type { Session, SessionExport, SaveAsTreeRequest, Step } from '@/types'
import { hasRatedSession, markSessionRated } from '@/lib/sessionRatings'
import { cn } from '@/lib/utils'
import { toast } from '@/lib/toast'

export function SessionDetailPage() {
  const { id } = useParams<{ id: string }>()
  const navigate = useNavigate()
  const { defaultExportFormat } = useUserPreferencesStore()
  const [session, setSession] = useState<Session | null>(null)
  const [isLoading, setIsLoading] = useState(true)
  const [error, setError] = useState<string | null>(null)
  const [isExporting, setIsExporting] = useState(false)
  const [exportFormat, setExportFormat] = useState<'markdown' | 'text' | 'html' | 'psa'>(defaultExportFormat)
  const [exportContent, setExportContent] = useState<string | null>(null)
  const [showPreview, setShowPreview] = useState(false)
  const [copied, setCopied] = useState(false)
  const [copiedPsa, setCopiedPsa] = useState(false)
  const [showSaveAsTreeModal, setShowSaveAsTreeModal] = useState(false)
  const [isSavingTree, setIsSavingTree] = useState(false)
  const [showRatingModal, setShowRatingModal] = useState(false)
  const [isSavingRatings, setIsSavingRatings] = useState(false)
  const [librarySteps, setLibrarySteps] = useState<Step[]>([])

  useEffect(() => {
    if (id) {
      loadSession()
    }
  }, [id])

  // Auto-show rating modal for completed sessions with library steps
  useEffect(() => {
    if (!session || !session.completed_at) return

    // Check if already rated
    if (hasRatedSession(session.id)) return

    // Extract library steps from custom_steps
    const stepsFromLibrary = session.custom_steps?.filter(
      (customStep) => {
        // Check if step_data is a Step (from library) by checking if it has an id
        const stepData = customStep.step_data
        return 'id' in stepData && stepData.id
      }
    ) || []

    if (stepsFromLibrary.length === 0) return

    // Extract the Step objects
    const steps = stepsFromLibrary.map((cs) => cs.step_data as Step)
    setLibrarySteps(steps)

    // Show modal after 1 second delay
    const timer = setTimeout(() => {
      setShowRatingModal(true)
    }, 1000)

    return () => clearTimeout(timer)
  }, [session])

  const loadSession = async () => {
    setIsLoading(true)
    setError(null)
    try {
      const data = await sessionsApi.get(id!)
      setSession(data)
    } catch (err) {
      setError('Failed to load session')
      console.error(err)
    } finally {
      setIsLoading(false)
    }
  }

  const getFilename = () => {
    if (!session) return 'export.txt'
    const ext = exportFormat === 'markdown' ? 'md' : exportFormat === 'html' ? 'html' : 'txt'  // psa and text both use .txt
    return `session-${session.ticket_number || session.id}.${ext}`
  }

  const fetchExportContent = async () => {
    if (!session) return null
    const options: SessionExport = {
      format: exportFormat,
      include_timestamps: true,
      include_tree_info: true,
    }
    return await sessionsApi.export(session.id, options)
  }

  const handlePreview = async () => {
    setIsExporting(true)
    try {
      const content = await fetchExportContent()
      if (content) {
        setExportContent(content)
        setShowPreview(true)
      }
    } catch (err) {
      console.error('Export failed:', err)
      toast.error('Failed to generate export preview')
    } finally {
      setIsExporting(false)
    }
  }

  const handleCopy = async () => {
    setIsExporting(true)
    try {
      const content = await fetchExportContent()
      if (content) {
        await navigator.clipboard.writeText(content)
        setCopied(true)
        setTimeout(() => setCopied(false), 2000)
        toast.success('Copied to clipboard')
      }
    } catch (err) {
      console.error('Copy failed:', err)
      toast.error('Failed to copy to clipboard')
    } finally {
      setIsExporting(false)
    }
  }

  const handleCopyForTicket = async () => {
    if (!session) return
    try {
      const options: SessionExport = {
        format: 'psa',
        include_timestamps: true,
        include_tree_info: true,
      }
      const content = await sessionsApi.export(session.id, options)
      if (content) {
        await navigator.clipboard.writeText(content)
        setCopiedPsa(true)
        setTimeout(() => setCopiedPsa(false), 2000)
        toast.success('Copied ticket notes to clipboard')
      }
    } catch (err) {
      console.error('Copy for ticket failed:', err)
      toast.error('Failed to copy ticket notes')
    }
  }

  const handleDownload = () => {
    if (!exportContent || !session) return
    const blob = new Blob([exportContent], { type: 'text/plain' })
    const url = URL.createObjectURL(blob)
    const a = document.createElement('a')
    a.href = url
    a.download = getFilename()
    document.body.appendChild(a)
    a.click()
    document.body.removeChild(a)
    URL.revokeObjectURL(url)
  }

  const handleSaveAsTree = async (data: SaveAsTreeRequest) => {
    if (!session) return
    setIsSavingTree(true)
    try {
      const result = await sessionsApi.saveAsTree(session.id, data)
      toast.success(result.message)
      setShowSaveAsTreeModal(false)
      // Navigate to tree editor with the new tree
      navigate(`/trees/${result.tree_id}/edit`)
    } catch (err) {
      console.error('Failed to save session as tree:', err)
      toast.error('Failed to save session as tree')
    } finally {
      setIsSavingTree(false)
    }
  }

  const getDefaultTreeName = () => {
    if (!session) return ''
    const treeName = session.tree_snapshot?.name || 'Tree'
    const ticket = session.ticket_number ? ` - ${session.ticket_number}` : ''
    return `${treeName}${ticket}`
  }

  const handleSubmitRatings = async (ratings: Map<string, { rating: number; helpful: boolean | null; review: string }>) => {
    if (!session) return
    setIsSavingRatings(true)
    try {
      // Submit each rating individually
      const ratingPromises = Array.from(ratings.entries()).map(([stepId, data]) =>
        stepsApi.rate(stepId, {
          rating: data.rating,
          review_text: data.review || undefined,
          was_helpful: data.helpful !== null ? data.helpful : undefined,
          session_id: session.id,
          is_verified_use: true
        })
      )

      await Promise.all(ratingPromises)

      toast.success(`Submitted ${ratings.size} rating${ratings.size > 1 ? 's' : ''}!`)
      markSessionRated(session.id)
      setShowRatingModal(false)
    } catch (err) {
      console.error('Failed to submit ratings:', err)
      toast.error('Failed to submit ratings')
    } finally {
      setIsSavingRatings(false)
    }
  }

  const formatDate = (dateString: string) => {
    return new Date(dateString).toLocaleString()
  }

  if (isLoading) {
    return (
      <div className="flex h-64 items-center justify-center">
        <div className="h-8 w-8 animate-spin rounded-full border-4 border-white/20 border-t-white" />
      </div>
    )
  }

  if (error || !session) {
    return (
      <div className="container mx-auto px-4 py-6 sm:px-6 sm:py-8">
        <div className="rounded-md border border-red-400/20 bg-red-400/10 p-4 text-red-400">
          {error || 'Session not found'}
        </div>
        <button
          onClick={() => navigate('/sessions')}
          className="mt-4 text-white hover:underline"
        >
          Back to sessions
        </button>
      </div>
    )
  }

  return (
    <div className="container mx-auto px-4 py-6 sm:px-6 sm:py-8">
      {/* Header */}
      <div className="mb-8">
        <div className="flex flex-col gap-4 sm:flex-row sm:items-start sm:justify-between">
          <div>
            <button
              onClick={() => navigate('/sessions')}
              className="mb-2 text-sm text-white/40 hover:text-white"
            >
              ← Back to sessions
            </button>
            <h1 className="text-2xl font-bold text-white sm:text-3xl">
              {session.ticket_number || 'Session Details'}
            </h1>
            <div className="mt-2 flex items-center gap-4 text-sm text-white/40">
              <span
                className={cn(
                  'flex items-center gap-1',
                  session.completed_at ? 'text-emerald-400' : 'text-yellow-400'
                )}
              >
                <span
                  className={cn(
                    'h-2.5 w-2.5 rounded-full',
                    session.completed_at ? 'bg-green-500' : 'bg-yellow-500'
                  )}
                />
                {session.completed_at ? 'Completed' : 'In Progress'}
              </span>
              {session.client_name && <span>Client: {session.client_name}</span>}
            </div>
          </div>

          {/* Actions */}
          <div className="flex flex-col gap-2 sm:flex-row sm:items-center">
            {/* Save as Tree - Only for completed sessions */}
            {session.completed_at && (
              <button
                onClick={() => setShowSaveAsTreeModal(true)}
                disabled={isSavingTree}
                className={cn(
                  'flex items-center gap-2 rounded-md border border-white/10 bg-transparent px-4 py-2 text-sm font-medium text-white/60',
                  'hover:bg-white/10 hover:text-white disabled:opacity-50'
                )}
              >
                <Save className="h-4 w-4" />
                Save as Tree
              </button>
            )}

            {/* Copy for Ticket */}
            <button
              onClick={handleCopyForTicket}
              className={cn(
                'flex items-center gap-2 rounded-md bg-white px-4 py-2 text-sm font-medium text-black',
                'hover:bg-white/90'
              )}
            >
              {copiedPsa ? <Check className="h-4 w-4" /> : <Copy className="h-4 w-4" />}
              {copiedPsa ? 'Copied!' : 'Copy for Ticket'}
            </button>

            {/* Export Controls */}
            <div className="flex items-center gap-2">
              <select
                value={exportFormat}
                onChange={(e) => setExportFormat(e.target.value as typeof exportFormat)}
                aria-label="Export format"
                className={cn(
                  'w-full rounded-md border border-white/10 bg-black/50 px-3 py-2 text-sm text-white sm:w-auto',
                  'focus:border-white/30 focus:outline-none focus:ring-1 focus:ring-white/20'
                )}
              >
                <option value="markdown">Markdown</option>
                <option value="text">Plain Text</option>
                <option value="html">HTML</option>
                <option value="psa">PSA / Ticket Note</option>
              </select>
              <button
                onClick={handleCopy}
                disabled={isExporting}
                title="Copy to clipboard"
                className={cn(
                  'rounded-md border border-white/10 bg-transparent p-2 text-white/60',
                  'hover:bg-white/10 hover:text-white disabled:opacity-50'
                )}
              >
                {copied ? <Check className="h-4 w-4 text-emerald-400" /> : <Copy className="h-4 w-4" />}
              </button>
              <button
                onClick={handlePreview}
                disabled={isExporting}
                className={cn(
                  'flex items-center gap-2 rounded-md bg-white px-4 py-2 text-sm font-medium text-black',
                  'hover:bg-white/90 disabled:opacity-50'
                )}
              >
                <Eye className="h-4 w-4" />
                {isExporting ? 'Loading...' : 'Preview'}
              </button>
            </div>
          </div>
        </div>
      </div>

      {/* Timeline */}
      <div className="mb-8">
        <h2 className="mb-4 text-lg font-semibold text-white">Decision Timeline</h2>
        <div className="space-y-4">
          <div className="flex items-center gap-3 text-sm">
            <span className="h-3 w-3 rounded-full bg-white" />
            <span className="text-white/40">
              Session started: {formatDate(session.started_at)}
            </span>
          </div>

          {session.decisions.map((decision, index) => (
            <div key={index} className="ml-1 border-l-2 border-white/[0.06] pl-6">
              <div className="relative">
                <span className="absolute -left-[1.625rem] top-1 h-2 w-2 rounded-full bg-white/20" />
                <div className="glass-card rounded-xl p-4">
                  {decision.question && (
                    <p className="font-medium text-white">{decision.question}</p>
                  )}
                  {decision.answer && (
                    <p className="mt-1 text-sm text-white">Answer: {decision.answer}</p>
                  )}
                  {decision.action_performed && (
                    <p className="mt-1 text-sm text-white/40">
                      Action: {decision.action_performed}
                    </p>
                  )}
                  {decision.notes && (
                    <p className="mt-2 rounded bg-white/5 p-2 text-sm text-white/40">
                      Notes: {decision.notes}
                    </p>
                  )}
                  <p className="mt-2 text-xs text-white/40">
                    {formatDate(decision.timestamp)}
                  </p>
                </div>
              </div>
            </div>
          ))}

          {session.completed_at && (
            <div className="flex items-center gap-3 text-sm">
              <span className="h-3 w-3 rounded-full bg-green-500" />
              <span className="text-emerald-400">
                Session completed: {formatDate(session.completed_at)}
              </span>
            </div>
          )}
        </div>
      </div>

      {/* Export Preview Modal */}
      <ExportPreviewModal
        isOpen={showPreview}
        onClose={() => setShowPreview(false)}
        content={exportContent || ''}
        filename={getFilename()}
        format={exportFormat}
        onDownload={handleDownload}
      />

      {/* Save as Tree Modal */}
      <SaveSessionAsTreeModal
        isOpen={showSaveAsTreeModal}
        onClose={() => setShowSaveAsTreeModal(false)}
        onSave={handleSaveAsTree}
        defaultTreeName={getDefaultTreeName()}
        isSaving={isSavingTree}
      />

      {/* Step Rating Modal */}
      <StepRatingModal
        isOpen={showRatingModal}
        onClose={() => setShowRatingModal(false)}
        onSubmit={handleSubmitRatings}
        librarySteps={librarySteps}
        isSaving={isSavingRatings}
      />
    </div>
  )
}

export default SessionDetailPage