export const dynamic = 'force-dynamic'

import { NextRequest, NextResponse } from 'next/server'
import { createClient } from '@/lib/supabase/server'
import { getSession } from '@/lib/auth/get-session'

export async function POST(
  request: NextRequest,
  { params }: { params: Promise<{ id: string }> }
) {
  const { id } = await params
  const session = await getSession()
  if (!session) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
  if (!['hse', 'admin'].includes(session.role))
    return NextResponse.json({ error: 'Forbidden' }, { status: 403 })

  const supabase = await createClient()

  const { data: incident } = await supabase
    .from('incidents').select('status').eq('id', id).single()
  if (!incident) return NextResponse.json({ error: 'Not found' }, { status: 404 })
  if (incident.status !== 'triaged')
    return NextResponse.json({ error: 'Incident must be triaged first' }, { status: 409 })

  const { count: existingCount } = await supabase
    .from('investigations')
    .select('id', { count: 'exact', head: true })
    .eq('incident_id', id)
  if ((existingCount ?? 0) > 0)
    return NextResponse.json({ error: 'Investigation already exists for this incident' }, { status: 409 })

  const body = await request.json()
  const method: 'five_why' | 'fishbone' | 'other' = body.method ?? 'five_why'

  const { data: inv, error } = await supabase
    .from('investigations')
    .insert({
      incident_id: id,
      investigator_id: session.sub,
      method,
      findings_text: body.findings_text ?? null,
      root_cause_summary: body.root_cause_summary ?? null,
      five_why_steps: method === 'five_why' ? (body.five_why_steps ?? []) : null,
      fishbone_categories: method === 'fishbone' ? (body.fishbone_categories ?? []) : null,
      alcohol_test_result: body.alcohol_test_result ?? null,
      urine_test_result: body.urine_test_result ?? null,
      witness_statement_refs: Array.isArray(body.witness_statement_refs) ? body.witness_statement_refs : [],
    })
    .select('id')
    .single()

  if (error || !inv) return NextResponse.json({ error: 'Insert failed' }, { status: 500 })

  await supabase
    .from('incidents')
    .update({ status: 'investigating' })
    .eq('id', id)

  await supabase.rpc('write_audit_log', {
    p_table_name: 'incidents',
    p_record_id: id,
    p_action: 'investigation_started',
    p_new_value: { status: 'investigating', investigation_id: inv.id },
  })

  return NextResponse.json({ id: inv.id })
}

export async function PATCH(
  request: NextRequest,
  { params }: { params: Promise<{ id: string }> }
) {
  const { id } = await params
  const session = await getSession()
  if (!session) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
  if (!['hse', 'admin'].includes(session.role))
    return NextResponse.json({ error: 'Forbidden' }, { status: 403 })

  const supabase = await createClient()

  const body = await request.json()
  const { investigation_id, complete, ...fields } = body

  if (!investigation_id) return NextResponse.json({ error: 'investigation_id required' }, { status: 422 })

  const updateData: Record<string, unknown> = {
    findings_text: fields.findings_text ?? null,
    root_cause_summary: fields.root_cause_summary ?? null,
    five_why_steps: fields.five_why_steps ?? null,
    fishbone_categories: fields.fishbone_categories ?? null,
    alcohol_test_result: fields.alcohol_test_result ?? null,
    urine_test_result: fields.urine_test_result ?? null,
    witness_statement_refs: Array.isArray(fields.witness_statement_refs) ? fields.witness_statement_refs : [],
  }
  if (complete) updateData.completed_at = new Date().toISOString()

  const { error } = await supabase
    .from('investigations')
    .update(updateData)
    .eq('id', investigation_id)
    .eq('incident_id', id)

  if (error) return NextResponse.json({ error: 'Update failed' }, { status: 500 })

  if (complete) {
    await supabase
      .from('incidents')
      .update({ status: 'capa_pending' })
      .eq('id', id)

    await supabase.rpc('write_audit_log', {
      p_table_name: 'incidents',
      p_record_id: id,
      p_action: 'investigation_completed',
      p_new_value: { status: 'capa_pending' },
    })
  }

  return NextResponse.json({ ok: true })
}