import { NextRequest, NextResponse } from 'next/server'

/**
 * SDK Flow API
 *
 * GET /api/sdk/v1/flow - Get current flow state and suggestions
 * POST /api/sdk/v1/flow/next - Navigate to next step
 * POST /api/sdk/v1/flow/previous - Navigate to previous step
 */

const SDK_STEPS = [
  // Phase 1
  { id: 'company-profile', phase: 1, order: 1, name: 'Unternehmensprofil', url: '/sdk/company-profile' },
  { id: 'use-case-assessment', phase: 1, order: 2, name: 'Anwendungsfall-Erfassung', url: '/sdk/advisory-board' },
  { id: 'screening', phase: 1, order: 3, name: 'System Screening', url: '/sdk/screening' },
  { id: 'modules', phase: 1, order: 4, name: 'Compliance Modules', url: '/sdk/modules' },
  { id: 'requirements', phase: 1, order: 5, name: 'Requirements', url: '/sdk/requirements' },
  { id: 'controls', phase: 1, order: 6, name: 'Controls', url: '/sdk/controls' },
  { id: 'evidence', phase: 1, order: 7, name: 'Evidence', url: '/sdk/evidence' },
  { id: 'audit-checklist', phase: 1, order: 8, name: 'Audit Checklist', url: '/sdk/audit-checklist' },
  { id: 'risks', phase: 1, order: 9, name: 'Risk Matrix', url: '/sdk/risks' },
  // Phase 2
  { id: 'ai-act', phase: 2, order: 1, name: 'AI Act Klassifizierung', url: '/sdk/ai-act' },
  { id: 'obligations', phase: 2, order: 2, name: 'Pflichtenübersicht', url: '/sdk/obligations' },
  { id: 'dsfa', phase: 2, order: 3, name: 'DSFA', url: '/sdk/dsfa' },
  { id: 'tom', phase: 2, order: 4, name: 'TOMs', url: '/sdk/tom' },
  { id: 'loeschfristen', phase: 2, order: 5, name: 'Löschfristen', url: '/sdk/loeschfristen' },
  { id: 'vvt', phase: 2, order: 6, name: 'Verarbeitungsverzeichnis', url: '/sdk/vvt' },
  { id: 'consent', phase: 2, order: 7, name: 'Rechtliche Vorlagen', url: '/sdk/consent' },
  { id: 'cookie-banner', phase: 2, order: 8, name: 'Cookie Banner', url: '/sdk/cookie-banner' },
  { id: 'einwilligungen', phase: 2, order: 9, name: 'Einwilligungen', url: '/sdk/einwilligungen' },
  { id: 'dsr', phase: 2, order: 10, name: 'DSR Portal', url: '/sdk/dsr' },
  { id: 'escalations', phase: 2, order: 11, name: 'Escalations', url: '/sdk/escalations' },
]

function getStepIndex(stepId: string): number {
  return SDK_STEPS.findIndex(s => s.id === stepId)
}

function getNextStep(currentStepId: string) {
  const currentIndex = getStepIndex(currentStepId)
  if (currentIndex === -1 || currentIndex >= SDK_STEPS.length - 1) {
    return null
  }
  return SDK_STEPS[currentIndex + 1]
}

function getPreviousStep(currentStepId: string) {
  const currentIndex = getStepIndex(currentStepId)
  if (currentIndex <= 0) {
    return null
  }
  return SDK_STEPS[currentIndex - 1]
}

export async function GET(request: NextRequest) {
  try {
    const { searchParams } = new URL(request.url)
    const currentStepId = searchParams.get('currentStep') || 'company-profile'

    const currentStep = SDK_STEPS.find(s => s.id === currentStepId)
    const nextStep = getNextStep(currentStepId)
    const previousStep = getPreviousStep(currentStepId)

    // Generate suggestions based on context
    const suggestions = [
      {
        type: 'NAVIGATION',
        label: nextStep ? `Weiter zu ${nextStep.name}` : 'Flow abgeschlossen',
        action: nextStep ? `navigate:${nextStep.url}` : null,
      },
      {
        type: 'ACTION',
        label: 'Checkpoint validieren',
        action: 'validate:current',
      },
      {
        type: 'HELP',
        label: 'Hilfe anzeigen',
        action: 'help:show',
      },
    ]

    return NextResponse.json({
      success: true,
      currentStep,
      nextStep,
      previousStep,
      totalSteps: SDK_STEPS.length,
      currentIndex: getStepIndex(currentStepId) + 1,
      suggestions,
      steps: SDK_STEPS,
    })
  } catch (error) {
    console.error('Failed to get flow:', error)
    return NextResponse.json(
      { error: 'Failed to get flow' },
      { status: 500 }
    )
  }
}

export async function POST(request: NextRequest) {
  try {
    const body = await request.json()
    const { action, currentStepId } = body

    if (!action || !currentStepId) {
      return NextResponse.json(
        { error: 'action and currentStepId are required' },
        { status: 400 }
      )
    }

    let targetStep = null

    switch (action) {
      case 'next':
        targetStep = getNextStep(currentStepId)
        break
      case 'previous':
        targetStep = getPreviousStep(currentStepId)
        break
      default:
        return NextResponse.json(
          { error: 'Invalid action' },
          { status: 400 }
        )
    }

    if (!targetStep) {
      return NextResponse.json(
        { error: 'No target step available' },
        { status: 400 }
      )
    }

    return NextResponse.json({
      success: true,
      targetStep,
      redirectUrl: targetStep.url,
    })
  } catch (error) {
    console.error('Failed to navigate flow:', error)
    return NextResponse.json(
      { error: 'Failed to navigate flow' },
      { status: 500 }
    )
  }
}