import { NextResponse } from 'next/server'
import { createClient } from '@/lib/supabase/server'
import { getSession } from '@/lib/auth/get-session'
import { validateIncidentInput, validateTypeDetails, type IncidentType, type MedicalStatus } from '@/lib/incidents/validate'
import { uploadEvidenceFile, type EvidenceStage } from '@/lib/supabase/storage'
import { sendNewIncidentEmail } from '@/lib/notifications/email'
import { sendWhatsAppMessage } from '@/lib/notifications/whatsapp'
import { createInAppNotifications } from '@/lib/notifications/in-app'
import { getApiKey } from '@/lib/settings'

export const dynamic = 'force-dynamic'

export async function POST(request: Request) {
  try {
    return await handlePost(request)
  } catch (err) {
    console.error('Unhandled error in POST /api/incidents:', err)
    return NextResponse.json({ error: 'Internal server error', details: [String(err)] }, { status: 500 })
  }
}

async function handlePost(request: Request) {
  const session = await getSession()
  if (!session) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })

  const supabase = await createClient()

  const since = new Date(Date.now() - 60_000).toISOString()
  const { count: recentIncidents } = await supabase
    .from('audit_log')
    .select('id', { count: 'exact', head: true })
    .eq('changed_by', session.sub)
    .eq('table_name', 'incidents')
    .eq('action', 'INSERT')
    .gte('changed_at', since)
  if ((recentIncidents ?? 0) > 0)
    return NextResponse.json({ error: 'Rate limited — please wait 60 seconds before submitting another incident' }, { status: 429 })

  let body: Record<string, unknown>
  let files: File[] = []

  const contentType = request.headers.get('content-type') ?? ''
  if (contentType.includes('multipart/form-data')) {
    const form = await request.formData()
    body = Object.fromEntries(
      [...form.entries()].filter(([, v]) => typeof v === 'string')
    ) as Record<string, unknown>
    files = form.getAll('files').filter((v): v is File => v instanceof File)
  } else {
    body = await request.json()
  }

  const input = {
    zone_token: body.zone_token as string,
    incident_type: body.incident_type as IncidentType,
    description: body.description as string,
    injury_involved: body.injury_involved === 'true' || body.injury_involved === true,
    asset_involved: body.asset_involved === 'true' || body.asset_involved === true,
    medical_status: body.medical_status as MedicalStatus | undefined || undefined,
    truck_id: (body.truck_id as string) || null,
  }

  const validation = validateIncidentInput(input)
  if (!validation.ok) {
    return NextResponse.json({ error: 'Validation failed', details: validation.errors }, { status: 422 })
  }

  let truckId: string | null = null
  if (input.incident_type === 'transport') {
    const { data: truck } = await supabase
      .from('trucks').select('id').eq('id', input.truck_id).eq('active', true).single()
    if (!truck) return NextResponse.json({ error: 'Validation failed', details: ['truck not found or inactive'] }, { status: 422 })
    truckId = truck.id
  }

  let rawDetails: Record<string, unknown> | undefined
  if (typeof body.type_details === 'string' && body.type_details) {
    try {
      rawDetails = JSON.parse(body.type_details)
    } catch {
      return NextResponse.json({ error: 'Validation failed', details: ['type_details must be valid JSON'] }, { status: 422 })
    }
  } else if (body.type_details && typeof body.type_details === 'object') {
    rawDetails = body.type_details as Record<string, unknown>
  }
  const detailsCheck = validateTypeDetails(input.incident_type, rawDetails)
  if (!detailsCheck.ok) {
    return NextResponse.json({ error: 'Validation failed', details: detailsCheck.errors }, { status: 422 })
  }

  const { data: zone, error: zoneError } = await supabase
    .from('zones')
    .select('id, site_id, active, sites(active)')
    .eq('qr_code_token', input.zone_token)
    .single()

  if (zoneError || !zone) {
    return NextResponse.json({ error: 'Zone not found' }, { status: 404 })
  }
  if (zone.active === false || (zone.sites as { active?: boolean } | null)?.active === false) {
    return NextResponse.json({ error: 'This location is no longer active for reporting.' }, { status: 409 })
  }

  const { data: incident, error: incidentError } = await supabase
    .from('incidents')
    .insert({
      incident_type: input.incident_type,
      site_id: zone.site_id,
      zone_id: zone.id,
      reported_by: session.sub,
      description: input.description.trim(),
      injury_involved: input.injury_involved,
      asset_involved: input.asset_involved,
      medical_status: input.injury_involved ? (input.medical_status ?? 'none') : null,
      type_details: detailsCheck.sanitized,
      truck_id: truckId,
    })
    .select('id, reference_no')
    .single()

  if (incidentError || !incident) {
    console.error('incident insert error:', incidentError)
    return NextResponse.json({ error: 'Failed to create incident' }, { status: 500 })
  }

  const evidenceRows: Array<{
    incident_id: string
    stage: EvidenceStage
    file_url: string
    file_type: string
    file_hash: string
    uploaded_by: string
  }> = []

  for (const file of files) {
    try {
      const { publicUrl, hash } = await uploadEvidenceFile(supabase, file, incident.id, 'report', session.sub)
      evidenceRows.push({
        incident_id: incident.id,
        stage: 'report',
        file_url: publicUrl,
        file_type: file.type,
        file_hash: hash,
        uploaded_by: session.sub,
      })
    } catch (err) {
      console.error('file upload error:', err)
    }
  }

  if (evidenceRows.length > 0) {
    await supabase.from('evidence_files').insert(evidenceRows)
  }

  await supabase.rpc('write_audit_log', {
    p_table_name: 'incidents',
    p_record_id: incident.id,
    p_action: 'INSERT',
    p_new_value: { incident_type: input.incident_type, reported_by: session.sub },
  })

  sendNewIncidentEmail(incident.id, zone.site_id, incident.reference_no ?? '', input.incident_type)
    .catch(err => console.error('email notification failed:', err))

  // WhatsApp alert — fire-and-forget alongside email
  ;(async () => {
    try {
      const phoneNumberId = await getApiKey('META_WHATSAPP_PHONE_NUMBER_ID')
      const accessToken = await getApiKey('META_WHATSAPP_ACCESS_TOKEN')
      const { data: siteData } = await supabase
        .from('sites').select('name').eq('id', zone.site_id).single()
      const siteName = (siteData as { name: string } | null)?.name ?? 'Unknown'
      const { data: recipients } = await supabase
        .from('users')
        .select('id, phone')
        .in('role', ['supervisor', 'hse'])
        .eq('site_id', zone.site_id)

      await createInAppNotifications(
        (recipients ?? []).map((r: { id: string }) => ({
          userId: r.id,
          title: `New ${input.incident_type.replace(/_/g, ' ')} incident ${incident.reference_no ?? ''} at ${siteName}`,
          link: `/hse/incidents/${incident.id}`,
          incidentId: incident.id,
        })),
      )

      for (const r of recipients ?? []) {
        const phone = (r as { phone: string | null }).phone ?? ''
        if (!phone) continue
        await sendWhatsAppMessage(
          phone,
          'ims_incident_alert',
          [incident.reference_no ?? '', input.incident_type, siteName],
          phoneNumberId,
          accessToken,
        )
      }
    } catch (err) {
      console.error('WhatsApp incident alert error:', err)
    }
  })()

  // Embed description asynchronously for future similarity search
  const supabaseForEmbed = supabase
  import('@/lib/settings').then(({ getApiKey }) =>
    getApiKey('GOOGLE_AI_API_KEY').then(googleAiKey =>
      import('@/lib/claude/embed').then(({ embedText }) =>
        embedText(input.description.trim(), googleAiKey).then(embedding =>
          supabase.from('incidents').update({
            embedding: `[${embedding.join(',')}]` as unknown as string,
          }).eq('id', incident.id)
        )
      )
    )
  ).catch(err => console.error('embed error:', err))

  return NextResponse.json({ id: incident.id, reference_no: incident.reference_no }, { status: 201 })
}