/**
 * API Proxy for edu-search-service Admin Operations
 *
 * Provides secure server-side access to edu-search-service API
 * with API key authentication handled server-side
 *
 * Seeds are fetched from Python Backend (port 8000)
 * Other operations (stats, crawl) go to Go edu-search-service (port 8084)
 */

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

const EDU_SEARCH_URL = process.env.EDU_SEARCH_URL || 'http://localhost:8084'
const BACKEND_URL = process.env.BACKEND_URL || 'http://localhost:8000'
const EDU_SEARCH_API_KEY = process.env.EDU_SEARCH_API_KEY || ''

// GET: Fetch seeds, stats, or health
export async function GET(request: NextRequest) {
  const searchParams = request.nextUrl.searchParams
  const action = searchParams.get('action')

  try {
    // Seeds come from Python Backend - fetch all pages for admin view
    if (action === 'seeds') {
      const category = searchParams.get('category')
      const pageSize = 200  // Max allowed by backend

      // Fetch first page to get total count
      let seedsUrl = `${BACKEND_URL}/v1/edu-search/seeds?page=1&page_size=${pageSize}`
      if (category) {
        seedsUrl += `&category=${category}`
      }

      const firstResponse = await fetch(seedsUrl, {
        headers: { 'Content-Type': 'application/json' },
      })

      if (!firstResponse.ok) {
        throw new Error(`Backend responded with ${firstResponse.status}`)
      }

      const firstData = await firstResponse.json()
      let allSeeds = firstData.seeds || []
      const total = firstData.total || allSeeds.length

      // Fetch additional pages if needed
      const totalPages = Math.ceil(total / pageSize)
      for (let page = 2; page <= totalPages; page++) {
        let nextUrl = `${BACKEND_URL}/v1/edu-search/seeds?page=${page}&page_size=${pageSize}`
        if (category) {
          nextUrl += `&category=${category}`
        }

        const nextResponse = await fetch(nextUrl, {
          headers: { 'Content-Type': 'application/json' },
        })

        if (nextResponse.ok) {
          const nextData = await nextResponse.json()
          allSeeds = allSeeds.concat(nextData.seeds || [])
        }
      }

      return NextResponse.json({
        seeds: allSeeds,
        total: total,
        page: 1,
        page_size: total,
      })
    }

    // Categories come from Python Backend
    if (action === 'categories') {
      const categoriesResponse = await fetch(`${BACKEND_URL}/v1/edu-search/categories`, {
        headers: { 'Content-Type': 'application/json' },
      })

      if (!categoriesResponse.ok) {
        throw new Error(`Backend responded with ${categoriesResponse.status}`)
      }

      const data = await categoriesResponse.json()
      // Backend returns array directly, wrap it for frontend compatibility
      const categories = Array.isArray(data) ? data : data.categories || []
      return NextResponse.json({ categories })
    }

    // Stats come from Python Backend
    if (action === 'stats') {
      const statsResponse = await fetch(`${BACKEND_URL}/v1/edu-search/stats`, {
        headers: { 'Content-Type': 'application/json' },
      })

      if (!statsResponse.ok) {
        throw new Error(`Backend responded with ${statsResponse.status}`)
      }

      const data = await statsResponse.json()
      return NextResponse.json(data)
    }

    // Other actions go to Go edu-search-service
    let endpoint = '/v1/health'

    switch (action) {
      case 'stats':
        endpoint = '/v1/admin/stats'
        break
      case 'health':
        endpoint = '/v1/health'
        break
      default:
        endpoint = '/v1/health'
    }

    const response = await fetch(`${EDU_SEARCH_URL}${endpoint}`, {
      headers: {
        'Authorization': `Bearer ${EDU_SEARCH_API_KEY}`,
        'Content-Type': 'application/json',
      },
    })

    if (!response.ok) {
      // Return mock data for development when service is not running
      if (action === 'stats') {
        return NextResponse.json({
          totalDocuments: 15234,
          totalSeeds: 127,
          lastCrawlTime: new Date().toISOString(),
          crawlStatus: 'idle',
          documentsPerCategory: {
            federal: 4521,
            states: 5234,
            science: 1234,
            universities: 2345,
            portals: 1900,
          },
          documentsPerDocType: {
            Lehrplan: 2345,
            Arbeitsblatt: 4567,
            Unterrichtsentwurf: 1234,
            Erlass_Verordnung: 890,
            Pruefung_Abitur: 567,
            Studie_Bericht: 345,
            Sonstiges: 5286,
          },
          avgTrustScore: 0.72,
        })
      }

      // Seeds are now handled by Python Backend above, this case shouldn't be reached

      return NextResponse.json({
        status: 'mock',
        message: 'edu-search-service not available, using mock data',
      })
    }

    const data = await response.json()
    return NextResponse.json(data)
  } catch (error) {
    console.error('edu-search API error:', error)

    // Return mock data on error
    if (action === 'health') {
      return NextResponse.json({
        status: 'mock',
        opensearch: 'unavailable',
        service: 'edu-search-service',
        version: '0.1.0',
      })
    }

    return NextResponse.json(
      { error: 'Failed to connect to edu-search-service' },
      { status: 503 }
    )
  }
}

// POST: Create seed (via Python Backend), or start crawl (via Go service)
export async function POST(request: NextRequest) {
  const searchParams = request.nextUrl.searchParams
  const action = searchParams.get('action')

  try {
    const body = await request.json()

    // Seed creation goes to Python Backend
    if (action === 'seed') {
      const response = await fetch(`${BACKEND_URL}/v1/edu-search/seeds`, {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
        },
        body: JSON.stringify(body),
      })

      if (!response.ok) {
        const errData = await response.json().catch(() => ({}))
        return NextResponse.json(
          { error: errData.detail || `Backend responded with ${response.status}` },
          { status: response.status }
        )
      }

      const data = await response.json()
      return NextResponse.json(data)
    }

    // Crawl start - calls both Legal Crawler (Python) and Go edu-search-service
    if (action === 'crawl') {
      const results: { legal?: unknown; eduSearch?: unknown } = {}

      // 1. Start Legal Crawler (Python Backend) - crawls Schulgesetze
      try {
        const legalResponse = await fetch(`${BACKEND_URL}/v1/legal-crawler/start`, {
          method: 'POST',
          headers: { 'Content-Type': 'application/json' },
        })
        if (legalResponse.ok) {
          results.legal = await legalResponse.json()
        } else {
          results.legal = { status: 'error', message: `Legal crawler returned ${legalResponse.status}` }
        }
      } catch (err) {
        results.legal = { status: 'error', message: 'Legal crawler not available' }
      }

      // 2. Start Go edu-search-service crawler (if available)
      try {
        const eduResponse = await fetch(`${EDU_SEARCH_URL}/v1/admin/crawl/start`, {
          method: 'POST',
          headers: {
            'Authorization': `Bearer ${EDU_SEARCH_API_KEY}`,
            'Content-Type': 'application/json',
          },
          body: JSON.stringify(body),
        })
        if (eduResponse.ok) {
          results.eduSearch = await eduResponse.json()
        } else {
          results.eduSearch = { status: 'skipped', message: 'Go edu-search-service not available' }
        }
      } catch (err) {
        results.eduSearch = { status: 'skipped', message: 'Go edu-search-service not running' }
      }

      return NextResponse.json({
        status: 'started',
        message: 'Crawl gestartet',
        results,
      })
    }

    // Legal Crawler Status
    if (action === 'legal-crawler-status') {
      try {
        const response = await fetch(`${BACKEND_URL}/v1/legal-crawler/status`, {
          headers: { 'Content-Type': 'application/json' },
        })
        if (response.ok) {
          const data = await response.json()
          return NextResponse.json(data)
        }
      } catch (err) {
        // Fall through to error response
      }
      return NextResponse.json({ status: 'error', message: 'Legal crawler not available' })
    }

    return NextResponse.json({ error: 'Invalid action' }, { status: 400 })
  } catch (error) {
    console.error('edu-search API POST error:', error)
    return NextResponse.json(
      { error: 'Failed to process request' },
      { status: 500 }
    )
  }
}

// PUT: Update seed (via Python Backend)
export async function PUT(request: NextRequest) {
  const searchParams = request.nextUrl.searchParams
  const seedId = searchParams.get('id')

  if (!seedId) {
    return NextResponse.json({ error: 'Seed ID required' }, { status: 400 })
  }

  try {
    const body = await request.json()

    const response = await fetch(`${BACKEND_URL}/v1/edu-search/seeds/${seedId}`, {
      method: 'PUT',
      headers: {
        'Content-Type': 'application/json',
      },
      body: JSON.stringify(body),
    })

    if (!response.ok) {
      const errData = await response.json().catch(() => ({}))
      return NextResponse.json(
        { error: errData.detail || `Backend responded with ${response.status}` },
        { status: response.status }
      )
    }

    const data = await response.json()
    return NextResponse.json(data)
  } catch (error) {
    console.error('edu-search API PUT error:', error)
    return NextResponse.json(
      { error: 'Failed to update seed' },
      { status: 500 }
    )
  }
}

// DELETE: Remove seed (via Python Backend)
export async function DELETE(request: NextRequest) {
  const searchParams = request.nextUrl.searchParams
  const seedId = searchParams.get('id')

  if (!seedId) {
    return NextResponse.json({ error: 'Seed ID required' }, { status: 400 })
  }

  try {
    const response = await fetch(`${BACKEND_URL}/v1/edu-search/seeds/${seedId}`, {
      method: 'DELETE',
      headers: {
        'Content-Type': 'application/json',
      },
    })

    if (!response.ok) {
      const errData = await response.json().catch(() => ({}))
      return NextResponse.json(
        { error: errData.detail || `Backend responded with ${response.status}` },
        { status: response.status }
      )
    }

    return NextResponse.json({ deleted: true, id: seedId })
  } catch (error) {
    console.error('edu-search API DELETE error:', error)
    return NextResponse.json(
      { error: 'Failed to delete seed' },
      { status: 500 }
    )
  }
}