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

const BACKEND_URL = process.env.BACKEND_URL || 'http://backend-compliance:8002'

/**
 * Proxy: GET /api/sdk/v1/canonical?endpoint=...
 *
 * Routes to backend canonical control endpoints:
 *   endpoint=frameworks   → GET /api/compliance/v1/canonical/frameworks
 *   endpoint=controls     → GET /api/compliance/v1/canonical/controls(?severity=...&domain=...)
 *   endpoint=control&id=  → GET /api/compliance/v1/canonical/controls/{id}
 *   endpoint=sources      → GET /api/compliance/v1/canonical/sources
 *   endpoint=licenses     → GET /api/compliance/v1/canonical/licenses
 */
export async function GET(request: NextRequest) {
  try {
    const { searchParams } = new URL(request.url)
    const endpoint = searchParams.get('endpoint') || 'frameworks'

    let backendPath: string

    switch (endpoint) {
      case 'frameworks':
        backendPath = '/api/compliance/v1/canonical/frameworks'
        break

      case 'controls': {
        const controlParams = new URLSearchParams()
        const passthrough = ['severity', 'domain', 'release_state', 'verification_method', 'category',
          'target_audience', 'source', 'search', 'control_type', 'exclude_duplicates', 'sort', 'order', 'limit', 'offset']
        for (const key of passthrough) {
          const val = searchParams.get(key)
          if (val) controlParams.set(key, val)
        }
        const qs = controlParams.toString()
        backendPath = `/api/compliance/v1/canonical/controls${qs ? `?${qs}` : ''}`
        break
      }

      case 'controls-count': {
        const countParams = new URLSearchParams()
        const countPassthrough = ['severity', 'domain', 'release_state', 'verification_method', 'category',
          'target_audience', 'source', 'search', 'control_type', 'exclude_duplicates']
        for (const key of countPassthrough) {
          const val = searchParams.get(key)
          if (val) countParams.set(key, val)
        }
        const countQs = countParams.toString()
        backendPath = `/api/compliance/v1/canonical/controls-count${countQs ? `?${countQs}` : ''}`
        break
      }

      case 'controls-meta':
        backendPath = '/api/compliance/v1/canonical/controls-meta'
        break

      case 'control': {
        const controlId = searchParams.get('id')
        if (!controlId) {
          return NextResponse.json({ error: 'Missing control id' }, { status: 400 })
        }
        backendPath = `/api/compliance/v1/canonical/controls/${encodeURIComponent(controlId)}`
        break
      }

      case 'sources':
        backendPath = '/api/compliance/v1/canonical/sources'
        break

      case 'licenses':
        backendPath = '/api/compliance/v1/canonical/licenses'
        break

      // Generator endpoints
      case 'generate-jobs':
        backendPath = '/api/compliance/v1/canonical/generate/jobs'
        break

      case 'generate-status': {
        const jobId = searchParams.get('jobId')
        if (!jobId) {
          return NextResponse.json({ error: 'Missing jobId' }, { status: 400 })
        }
        backendPath = `/api/compliance/v1/canonical/generate/status/${encodeURIComponent(jobId)}`
        break
      }

      case 'review-queue': {
        const state = searchParams.get('release_state') || 'needs_review'
        backendPath = `/api/compliance/v1/canonical/generate/review-queue?release_state=${encodeURIComponent(state)}`
        break
      }

      case 'processed-stats':
        backendPath = '/api/compliance/v1/canonical/generate/processed-stats'
        break

      case 'categories':
        backendPath = '/api/compliance/v1/canonical/categories'
        break

      case 'traceability': {
        const traceId = searchParams.get('id')
        if (!traceId) {
          return NextResponse.json({ error: 'Missing control id' }, { status: 400 })
        }
        backendPath = `/api/compliance/v1/canonical/controls/${encodeURIComponent(traceId)}/traceability`
        break
      }

      case 'provenance': {
        const provId = searchParams.get('id')
        if (!provId) {
          return NextResponse.json({ error: 'Missing control id' }, { status: 400 })
        }
        backendPath = `/api/compliance/v1/canonical/controls/${encodeURIComponent(provId)}/provenance`
        break
      }

      case 'atomic-stats':
        backendPath = '/api/compliance/v1/canonical/controls/atomic-stats'
        break

      case 'similar': {
        const simControlId = searchParams.get('id')
        if (!simControlId) {
          return NextResponse.json({ error: 'Missing control id' }, { status: 400 })
        }
        const simThreshold = searchParams.get('threshold') || '0.85'
        backendPath = `/api/compliance/v1/canonical/controls/${encodeURIComponent(simControlId)}/similar?threshold=${simThreshold}`
        break
      }

      case 'blocked-sources':
        backendPath = '/api/compliance/v1/canonical/blocked-sources'
        break

      case 'controls-customer': {
        const custSeverity = searchParams.get('severity')
        const custDomain = searchParams.get('domain')
        const custParams = new URLSearchParams()
        if (custSeverity) custParams.set('severity', custSeverity)
        if (custDomain) custParams.set('domain', custDomain)
        const custQs = custParams.toString()
        backendPath = `/api/compliance/v1/canonical/controls-customer${custQs ? `?${custQs}` : ''}`
        break
      }

      default:
        return NextResponse.json({ error: `Unknown endpoint: ${endpoint}` }, { status: 400 })
    }

    const response = await fetch(`${BACKEND_URL}${backendPath}`)

    if (!response.ok) {
      if (response.status === 404) {
        return NextResponse.json(null, { status: 404 })
      }
      const errorText = await response.text()
      return NextResponse.json(
        { error: 'Backend error', details: errorText },
        { status: response.status }
      )
    }

    return NextResponse.json(await response.json())
  } catch (error) {
    console.error('Canonical control proxy error:', error)
    return NextResponse.json(
      { error: 'Failed to connect to backend' },
      { status: 503 }
    )
  }
}

/**
 * Proxy: POST /api/sdk/v1/canonical?endpoint=...
 *
 *   endpoint=create-control         → POST /api/compliance/v1/canonical/controls
 *   endpoint=similarity-check&id=   → POST /api/compliance/v1/canonical/controls/{id}/similarity-check
 */
export async function POST(request: NextRequest) {
  try {
    const { searchParams } = new URL(request.url)
    const endpoint = searchParams.get('endpoint')
    const body = await request.json()

    let backendPath: string

    if (endpoint === 'create-control') {
      backendPath = '/api/compliance/v1/canonical/controls'
    } else if (endpoint === 'generate') {
      backendPath = '/api/compliance/v1/canonical/generate'
    } else if (endpoint === 'review') {
      const controlId = searchParams.get('id')
      if (!controlId) {
        return NextResponse.json({ error: 'Missing control id' }, { status: 400 })
      }
      backendPath = `/api/compliance/v1/canonical/generate/review/${encodeURIComponent(controlId)}`
    } else if (endpoint === 'bulk-review') {
      backendPath = '/api/compliance/v1/canonical/generate/bulk-review'
    } else if (endpoint === 'blocked-sources-cleanup') {
      backendPath = '/api/compliance/v1/canonical/blocked-sources/cleanup'
    } else if (endpoint === 'similarity-check') {
      const controlId = searchParams.get('id')
      if (!controlId) {
        return NextResponse.json({ error: 'Missing control id' }, { status: 400 })
      }
      backendPath = `/api/compliance/v1/canonical/controls/${encodeURIComponent(controlId)}/similarity-check`
    } else {
      return NextResponse.json({ error: `Unknown POST endpoint: ${endpoint}` }, { status: 400 })
    }

    const response = await fetch(`${BACKEND_URL}${backendPath}`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify(body),
    })

    if (!response.ok) {
      const errorText = await response.text()
      return NextResponse.json(
        { error: 'Backend error', details: errorText },
        { status: response.status }
      )
    }

    return NextResponse.json(await response.json(), { status: response.status })
  } catch (error) {
    console.error('Canonical control POST proxy error:', error)
    return NextResponse.json(
      { error: 'Failed to connect to backend' },
      { status: 503 }
    )
  }
}

/**
 * Proxy: PUT /api/sdk/v1/canonical?endpoint=update-control&id=AUTH-001
 *
 * Routes to: PUT /api/compliance/v1/canonical/controls/{id}
 */
export async function PUT(request: NextRequest) {
  try {
    const { searchParams } = new URL(request.url)
    const controlId = searchParams.get('id')
    if (!controlId) {
      return NextResponse.json({ error: 'Missing control id' }, { status: 400 })
    }

    const body = await request.json()
    const response = await fetch(
      `${BACKEND_URL}/api/compliance/v1/canonical/controls/${encodeURIComponent(controlId)}`,
      {
        method: 'PUT',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(body),
      }
    )

    if (!response.ok) {
      const errorText = await response.text()
      return NextResponse.json(
        { error: 'Backend error', details: errorText },
        { status: response.status }
      )
    }

    return NextResponse.json(await response.json())
  } catch (error) {
    console.error('Canonical control PUT proxy error:', error)
    return NextResponse.json(
      { error: 'Failed to connect to backend' },
      { status: 503 }
    )
  }
}

/**
 * Proxy: DELETE /api/sdk/v1/canonical?id=AUTH-001
 *
 * Routes to: DELETE /api/compliance/v1/canonical/controls/{id}
 */
export async function DELETE(request: NextRequest) {
  try {
    const { searchParams } = new URL(request.url)
    const controlId = searchParams.get('id')
    if (!controlId) {
      return NextResponse.json({ error: 'Missing control id' }, { status: 400 })
    }

    const response = await fetch(
      `${BACKEND_URL}/api/compliance/v1/canonical/controls/${encodeURIComponent(controlId)}`,
      { method: 'DELETE' }
    )

    if (!response.ok && response.status !== 204) {
      const errorText = await response.text()
      return NextResponse.json(
        { error: 'Backend error', details: errorText },
        { status: response.status }
      )
    }

    return new NextResponse(null, { status: 204 })
  } catch (error) {
    console.error('Canonical control DELETE proxy error:', error)
    return NextResponse.json(
      { error: 'Failed to connect to backend' },
      { status: 503 }
    )
  }
}