'use client'
import React, { useState, useCallback, useEffect, useMemo } from 'react'
import type { ScopeProfilingAnswer, ScopeProfilingQuestion } from '@/lib/sdk/compliance-scope-types'
import { SCOPE_QUESTION_BLOCKS, getBlockProgress, getTotalProgress, getAnswerValue, prefillFromCompanyProfile, getProfileInfoForBlock, getAutoFilledScoringAnswers, getUnansweredRequiredQuestions } from '@/lib/sdk/compliance-scope-profiling'
import type { ScopeQuestionBlockId } from '@/lib/sdk/compliance-scope-types'
import { useSDK } from '@/lib/sdk'

interface ScopeWizardTabProps {
  answers: ScopeProfilingAnswer[]
  onAnswersChange: (answers: ScopeProfilingAnswer[]) => void
  onEvaluate: () => void
  canEvaluate: boolean
  isEvaluating: boolean
  completionStats: { total: number; answered: number; percentage: number; isComplete: boolean }
}

export function ScopeWizardTab({
  answers,
  onAnswersChange,
  onEvaluate,
  canEvaluate,
  isEvaluating,
  completionStats,
}: ScopeWizardTabProps) {
  const [currentBlockIndex, setCurrentBlockIndex] = useState(0)
  const [expandedHelp, setExpandedHelp] = useState<Set<string>>(new Set())
  const currentBlock = SCOPE_QUESTION_BLOCKS[currentBlockIndex]
  const totalProgress = getTotalProgress(answers)

  // Load companyProfile from SDK context
  const { state: sdkState } = useSDK()
  const companyProfile = sdkState.companyProfile

  // Track which question IDs were prefilled from profile
  const [prefilledIds, setPrefilledIds] = useState<Set<string>>(new Set())

  // Auto-prefill from company profile on mount if answers are empty
  useEffect(() => {
    if (companyProfile && answers.length === 0) {
      const prefilled = prefillFromCompanyProfile(companyProfile)
      // Also inject auto-filled scoring answers for questions removed from UI
      const autoFilled = getAutoFilledScoringAnswers(companyProfile)
      const allPrefilled = [...prefilled, ...autoFilled]
      if (allPrefilled.length > 0) {
        onAnswersChange(allPrefilled)
        setPrefilledIds(new Set(allPrefilled.map(a => a.questionId)))
      }
    }
    // Only run on mount
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [])

  const handleAnswerChange = useCallback(
    (questionId: string, value: string | string[] | boolean | number) => {
      const existingIndex = answers.findIndex((a) => a.questionId === questionId)
      if (existingIndex >= 0) {
        const newAnswers = [...answers]
        newAnswers[existingIndex] = { questionId, value }
        onAnswersChange(newAnswers)
      } else {
        onAnswersChange([...answers, { questionId, value }])
      }
      // Remove from prefilled set when user manually changes
      if (prefilledIds.has(questionId)) {
        setPrefilledIds(prev => {
          const next = new Set(prev)
          next.delete(questionId)
          return next
        })
      }
    },
    [answers, onAnswersChange, prefilledIds]
  )

  const handlePrefillFromProfile = useCallback(() => {
    if (!companyProfile) return
    const prefilled = prefillFromCompanyProfile(companyProfile)
    const autoFilled = getAutoFilledScoringAnswers(companyProfile)
    const allPrefilled = [...prefilled, ...autoFilled]
    // Merge with existing answers: prefilled values for questions not yet answered
    const existingIds = new Set(answers.map(a => a.questionId))
    const newAnswers = [...answers]
    const newPrefilledIds = new Set(prefilledIds)
    for (const pa of allPrefilled) {
      if (!existingIds.has(pa.questionId)) {
        newAnswers.push(pa)
        newPrefilledIds.add(pa.questionId)
      }
    }
    onAnswersChange(newAnswers)
    setPrefilledIds(newPrefilledIds)
  }, [companyProfile, answers, onAnswersChange, prefilledIds])

  const handleNext = useCallback(() => {
    if (currentBlockIndex < SCOPE_QUESTION_BLOCKS.length - 1) {
      setCurrentBlockIndex(currentBlockIndex + 1)
    } else if (canEvaluate) {
      onEvaluate()
    }
  }, [currentBlockIndex, canEvaluate, onEvaluate])

  const handleBack = useCallback(() => {
    if (currentBlockIndex > 0) {
      setCurrentBlockIndex(currentBlockIndex - 1)
    }
  }, [currentBlockIndex])

  const toggleHelp = useCallback((questionId: string) => {
    setExpandedHelp(prev => {
      const next = new Set(prev)
      if (next.has(questionId)) {
        next.delete(questionId)
      } else {
        next.add(questionId)
      }
      return next
    })
  }, [])

  // Check if a question was prefilled from company profile
  const isPrefilledFromProfile = useCallback((questionId: string) => {
    return prefilledIds.has(questionId)
  }, [prefilledIds])

  const renderHelpText = (question: ScopeProfilingQuestion) => {
    if (!question.helpText) return null

    return (
      <>
        <button
          type="button"
          className="ml-2 text-blue-400 hover:text-blue-600 inline-flex items-center"
          onClick={(e) => {
            e.preventDefault()
            toggleHelp(question.id)
          }}
        >
          <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
            <path
              strokeLinecap="round"
              strokeLinejoin="round"
              strokeWidth={2}
              d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z"
            />
          </svg>
        </button>
        {expandedHelp.has(question.id) && (
          <div className="flex items-start gap-2 mt-2 p-2.5 bg-blue-50 rounded-lg text-xs text-blue-700 leading-relaxed">
            <svg className="w-4 h-4 mt-0.5 flex-shrink-0 text-blue-500" fill="none" stroke="currentColor" viewBox="0 0 24 24">
              <path
                strokeLinecap="round"
                strokeLinejoin="round"
                strokeWidth={2}
                d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z"
              />
            </svg>
            <span>{question.helpText}</span>
          </div>
        )}
      </>
    )
  }

  const renderPrefilledBadge = (questionId: string) => {
    if (!isPrefilledFromProfile(questionId)) return null
    return (
      <span className="ml-2 inline-flex items-center px-2 py-0.5 rounded-full text-xs font-medium bg-green-100 text-green-700">
        Aus Profil
      </span>
    )
  }

  const renderQuestion = (question: ScopeProfilingQuestion) => {
    const currentValue = getAnswerValue(answers, question.id)

    switch (question.type) {
      case 'boolean':
        return (
          <div className="space-y-2">
            <div className="flex items-start justify-between">
              <div className="flex items-center flex-wrap gap-1">
                <span className="text-sm font-medium text-gray-900">
                  {question.question}
                </span>
                {question.required && <span className="text-red-500 ml-1">*</span>}
                {renderPrefilledBadge(question.id)}
                {renderHelpText(question)}
              </div>
            </div>
            <div className="flex gap-3">
              <button
                type="button"
                onClick={() => handleAnswerChange(question.id, true)}
                className={`flex-1 py-2 px-4 rounded-lg border-2 transition-all ${
                  currentValue === true
                    ? 'border-purple-500 bg-purple-50 text-purple-700 font-medium'
                    : 'border-gray-300 bg-white text-gray-700 hover:border-gray-400'
                }`}
              >
                Ja
              </button>
              <button
                type="button"
                onClick={() => handleAnswerChange(question.id, false)}
                className={`flex-1 py-2 px-4 rounded-lg border-2 transition-all ${
                  currentValue === false
                    ? 'border-purple-500 bg-purple-50 text-purple-700 font-medium'
                    : 'border-gray-300 bg-white text-gray-700 hover:border-gray-400'
                }`}
              >
                Nein
              </button>
            </div>
          </div>
        )

      case 'single':
        return (
          <div className="space-y-2">
            <div className="flex items-center flex-wrap gap-1">
              <span className="text-sm font-medium text-gray-900">
                {question.question}
              </span>
              {question.required && <span className="text-red-500 ml-1">*</span>}
              {renderPrefilledBadge(question.id)}
              {renderHelpText(question)}
            </div>
            <div className="space-y-2">
              {question.options?.map((option) => (
                <button
                  key={option.value}
                  type="button"
                  onClick={() => handleAnswerChange(question.id, option.value)}
                  className={`w-full text-left py-3 px-4 rounded-lg border-2 transition-all ${
                    currentValue === option.value
                      ? 'border-purple-500 bg-purple-50 text-purple-700 font-medium'
                      : 'border-gray-300 bg-white text-gray-700 hover:border-gray-400'
                  }`}
                >
                  {option.label}
                </button>
              ))}
            </div>
          </div>
        )

      case 'multi':
        return (
          <div className="space-y-2">
            <div className="flex items-center flex-wrap gap-1">
              <span className="text-sm font-medium text-gray-900">
                {question.question}
              </span>
              {question.required && <span className="text-red-500 ml-1">*</span>}
              {renderPrefilledBadge(question.id)}
              {renderHelpText(question)}
            </div>
            <div className="space-y-2">
              {question.options?.map((option) => {
                const selectedValues = Array.isArray(currentValue) ? currentValue as string[] : []
                const isChecked = selectedValues.includes(option.value)
                return (
                  <label
                    key={option.value}
                    className={`flex items-center gap-3 py-3 px-4 rounded-lg border-2 cursor-pointer transition-all ${
                      isChecked
                        ? 'border-purple-500 bg-purple-50'
                        : 'border-gray-300 bg-white hover:border-gray-400'
                    }`}
                  >
                    <input
                      type="checkbox"
                      checked={isChecked}
                      onChange={(e) => {
                        const newValues = e.target.checked
                          ? [...selectedValues, option.value]
                          : selectedValues.filter((v) => v !== option.value)
                        handleAnswerChange(question.id, newValues)
                      }}
                      className="w-5 h-5 text-purple-600 border-gray-300 rounded focus:ring-purple-500"
                    />
                    <span className={isChecked ? 'text-purple-700 font-medium' : 'text-gray-700'}>
                      {option.label}
                    </span>
                  </label>
                )
              })}
            </div>
          </div>
        )

      case 'number':
        return (
          <div className="space-y-2">
            <div className="flex items-center flex-wrap gap-1">
              <span className="text-sm font-medium text-gray-900">
                {question.question}
              </span>
              {question.required && <span className="text-red-500 ml-1">*</span>}
              {renderPrefilledBadge(question.id)}
              {renderHelpText(question)}
            </div>
            <input
              type="number"
              value={currentValue != null ? String(currentValue) : ''}
              onChange={(e) => handleAnswerChange(question.id, parseInt(e.target.value, 10))}
              className="w-full px-4 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-purple-500 focus:border-transparent"
              placeholder="Zahl eingeben"
            />
          </div>
        )

      case 'text':
        return (
          <div className="space-y-2">
            <div className="flex items-center flex-wrap gap-1">
              <span className="text-sm font-medium text-gray-900">
                {question.question}
              </span>
              {question.required && <span className="text-red-500 ml-1">*</span>}
              {renderPrefilledBadge(question.id)}
              {renderHelpText(question)}
            </div>
            <input
              type="text"
              value={currentValue != null ? String(currentValue) : ''}
              onChange={(e) => handleAnswerChange(question.id, e.target.value)}
              className="w-full px-4 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-purple-500 focus:border-transparent"
              placeholder="Text eingeben"
            />
          </div>
        )

      default:
        return null
    }
  }

  return (
    <div className="flex gap-6 h-full">
      {/* Left Sidebar - Block Navigation */}
      <div className="w-64 flex-shrink-0">
        <div className="bg-white rounded-xl border border-gray-200 p-4 sticky top-4">
          <h3 className="text-sm font-semibold text-gray-900 mb-3">Fortschritt</h3>
          <div className="space-y-2">
            {SCOPE_QUESTION_BLOCKS.map((block, idx) => {
              const progress = getBlockProgress(answers, block.id)
              const isActive = idx === currentBlockIndex
              const unanswered = getUnansweredRequiredQuestions(answers, block.id)
              const hasRequired = block.questions.some(q => q.required)
              const allRequiredDone = hasRequired && unanswered.length === 0

              return (
                <button
                  key={block.id}
                  type="button"
                  onClick={() => setCurrentBlockIndex(idx)}
                  className={`w-full text-left px-3 py-2 rounded-lg transition-all ${
                    isActive
                      ? 'bg-purple-50 border-2 border-purple-500'
                      : 'bg-gray-50 border border-gray-200 hover:border-gray-300'
                  }`}
                >
                  <div className="flex items-center justify-between mb-1">
                    <span className={`text-sm font-medium ${isActive ? 'text-purple-700' : 'text-gray-700'}`}>
                      {block.title}
                    </span>
                    {allRequiredDone ? (
                      <span className="flex items-center gap-1 text-xs font-semibold text-green-600">
                        <svg className="w-3.5 h-3.5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                          <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2.5} d="M5 13l4 4L19 7" />
                        </svg>
                      </span>
                    ) : !hasRequired ? (
                      <span className="text-xs text-gray-400">(nur optional)</span>
                    ) : (
                      <span className="text-xs font-semibold text-orange-600">
                        {unanswered.length} offen
                      </span>
                    )}
                  </div>
                  <div className="w-full bg-gray-200 rounded-full h-1.5 overflow-hidden">
                    <div
                      className={`h-full transition-all ${
                        allRequiredDone
                          ? 'bg-green-500'
                          : !hasRequired
                            ? 'bg-gray-300'
                            : 'bg-orange-400'
                      }`}
                      style={{ width: `${progress}%` }}
                    />
                  </div>
                </button>
              )
            })}
          </div>
        </div>
      </div>

      {/* Main Content Area */}
      <div className="flex-1 space-y-6">
        {/* Progress Bar */}
        <div className="bg-white rounded-xl border border-gray-200 p-4">
          <div className="flex items-center justify-between mb-2">
            <span className="text-sm font-medium text-gray-700">Gesamtfortschritt</span>
            <div className="flex items-center gap-3">
              <span className="text-sm text-gray-500">
                {completionStats.answered} / {completionStats.total} Fragen
              </span>
              <span className="text-sm font-bold text-gray-900">{totalProgress}%</span>
            </div>
          </div>
          <div className="w-full bg-gray-200 rounded-full h-3 overflow-hidden">
            <div
              className="h-full bg-gradient-to-r from-purple-500 to-blue-500 transition-all duration-500"
              style={{ width: `${totalProgress}%` }}
            />
          </div>

          {/* Clickable unanswered required questions summary */}
          {(() => {
            const allUnanswered = getUnansweredRequiredQuestions(answers)
            if (allUnanswered.length === 0) return null

            // Group by block
            const byBlock = new Map<string, { blockTitle: string; blockIndex: number; count: number }>()
            for (const item of allUnanswered) {
              if (!byBlock.has(item.blockId)) {
                const blockIndex = SCOPE_QUESTION_BLOCKS.findIndex(b => b.id === item.blockId)
                byBlock.set(item.blockId, { blockTitle: item.blockTitle, blockIndex, count: 0 })
              }
              byBlock.get(item.blockId)!.count++
            }

            return (
              <div className="mt-3 flex flex-wrap items-center gap-1.5 text-xs">
                <span className="text-orange-600 font-medium">⚠ Offene Pflichtfragen:</span>
                {Array.from(byBlock.entries()).map(([blockId, info], i) => (
                  <React.Fragment key={blockId}>
                    {i > 0 && <span className="text-gray-300">·</span>}
                    <button
                      type="button"
                      onClick={() => setCurrentBlockIndex(info.blockIndex)}
                      className="text-orange-700 hover:text-orange-900 hover:underline font-medium"
                    >
                      {info.blockTitle} ({info.count})
                    </button>
                  </React.Fragment>
                ))}
              </div>
            )
          })()}
        </div>

        {/* Current Block */}
        <div className="bg-white rounded-xl border border-gray-200 p-6">
          <div className="flex items-start justify-between mb-6">
            <div>
              <h2 className="text-2xl font-bold text-gray-900 mb-2">{currentBlock.title}</h2>
              <p className="text-gray-600">{currentBlock.description}</p>
            </div>
            {companyProfile && (
              <button
                type="button"
                onClick={handlePrefillFromProfile}
                className="px-4 py-2 text-sm bg-blue-50 text-blue-700 border border-blue-300 rounded-lg hover:bg-blue-100 transition-colors whitespace-nowrap"
              >
                Aus Profil uebernehmen
              </button>
            )}
          </div>

          {/* "Aus Profil" Info Box — shown for blocks that have auto-filled data */}
          {companyProfile && (() => {
            const profileItems = getProfileInfoForBlock(companyProfile, currentBlock.id as ScopeQuestionBlockId)
            if (profileItems.length === 0) return null
            return (
              <div className="mb-6 p-4 bg-blue-50 border border-blue-200 rounded-lg">
                <div className="flex items-start justify-between">
                  <div>
                    <h4 className="text-sm font-medium text-blue-900 mb-2 flex items-center gap-2">
                      <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                        <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 12h6m-6 4h6m2 5H7a2 2 0 01-2-2V5a2 2 0 012-2h5.586a1 1 0 01.707.293l5.414 5.414a1 1 0 01.293.707V19a2 2 0 01-2 2z" />
                      </svg>
                      Aus Unternehmensprofil
                    </h4>
                    <div className="flex flex-wrap gap-x-4 gap-y-1 text-sm text-blue-800">
                      {profileItems.map(item => (
                        <span key={item.label}>
                          <span className="font-medium">{item.label}:</span> {item.value}
                        </span>
                      ))}
                    </div>
                  </div>
                  <a
                    href="/sdk/company-profile"
                    className="text-sm text-blue-600 hover:text-blue-800 font-medium whitespace-nowrap flex items-center gap-1"
                  >
                    Profil bearbeiten
                    <svg className="w-3 h-3" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                      <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 5l7 7-7 7" />
                    </svg>
                  </a>
                </div>
              </div>
            )
          })()}

          {/* Questions */}
          <div className="space-y-6">
            {currentBlock.questions.map((question) => {
              const isAnswered = answers.some(a => a.questionId === question.id)
              const borderClass = question.required
                ? isAnswered
                  ? 'border-l-4 border-l-green-400 pl-4'
                  : 'border-l-4 border-l-orange-400 pl-4'
                : ''
              return (
                <div key={question.id} className={`border-b border-gray-100 pb-6 last:border-b-0 last:pb-0 ${borderClass}`}>
                  {renderQuestion(question)}
                </div>
              )
            })}
          </div>
        </div>

        {/* Navigation Buttons */}
        <div className="flex items-center justify-between bg-white rounded-xl border border-gray-200 p-4">
          <button
            type="button"
            onClick={handleBack}
            disabled={currentBlockIndex === 0}
            className="px-6 py-2 border border-gray-300 text-gray-700 rounded-lg hover:bg-gray-50 transition-colors disabled:opacity-50 disabled:cursor-not-allowed"
          >
            Zurueck
          </button>
          <span className="text-sm text-gray-600">
            Block {currentBlockIndex + 1} von {SCOPE_QUESTION_BLOCKS.length}
          </span>
          {currentBlockIndex === SCOPE_QUESTION_BLOCKS.length - 1 ? (
            <button
              type="button"
              onClick={onEvaluate}
              disabled={!canEvaluate || isEvaluating}
              className="px-6 py-2 bg-purple-600 text-white rounded-lg hover:bg-purple-700 transition-colors font-medium disabled:opacity-50 disabled:cursor-not-allowed"
            >
              {isEvaluating ? 'Evaluiere...' : 'Auswertung starten'}
            </button>
          ) : (
            <button
              type="button"
              onClick={handleNext}
              className="px-6 py-2 bg-purple-600 text-white rounded-lg hover:bg-purple-700 transition-colors font-medium"
            >
              Weiter
            </button>
          )}
        </div>
      </div>
    </div>
  )
}