import type { SupabaseClient } from '@supabase/supabase-js'

export type EvidenceStage = 'report' | 'response' | 'investigation' | 'capa' | 'verification'

export async function uploadEvidenceFile(
  supabase: SupabaseClient,
  file: File,
  incidentId: string,
  stage: EvidenceStage,
): Promise<{ path: string; publicUrl: string; hash: string }> {
  // Fix 3: Safe auth.getUser() destructuring
  const { data, error: authError } = await supabase.auth.getUser()
  if (authError || !data?.user) throw new Error('Not authenticated')
  const user = data.user

  // Fix 2: Server-side size limit before processing
  const isVideo = file.type.startsWith('video/')
  const maxBytes = isVideo ? 200 * 1024 * 1024 : 10 * 1024 * 1024
  if (file.size > maxBytes) {
    throw new Error(`File too large: max ${isVideo ? '200MB' : '10MB'} for this file type`)
  }

  const ext = file.name.split('.').pop() ?? 'bin'
  const filename = `${Date.now()}-${Math.random().toString(36).slice(2)}.${ext}`
  const path = `${user.id}/${incidentId}/${stage}/${filename}`

  const hash = await computeHash(file)

  const { data: uploadData, error } = await supabase.storage
    .from('evidence')
    .upload(path, file, { contentType: file.type, upsert: false })

  if (error) throw new Error(error.message)

  // Fix 1: Use createSignedUrl (private bucket) — 10-year URL for DB storage
  const { data: signedData, error: signedError } = await supabase.storage
    .from('evidence')
    .createSignedUrl(uploadData.path, 315360000) // ~10 years
  if (signedError || !signedData) throw new Error(signedError?.message ?? 'Failed to sign URL')

  return { path: uploadData.path, publicUrl: signedData.signedUrl, hash }
}

// Fix 1: getEvidenceUrl is now async, uses 1-hour signed URL
export async function getEvidenceUrl(supabase: SupabaseClient, path: string): Promise<string> {
  const { data, error } = await supabase.storage.from('evidence').createSignedUrl(path, 3600)
  if (error || !data) throw new Error(error?.message ?? 'Failed to sign URL')
  return data.signedUrl
}

async function computeHash(file: File): Promise<string> {
  const buffer = await file.arrayBuffer()
  const hashBuffer = await crypto.subtle.digest('SHA-256', buffer)
  return Array.from(new Uint8Array(hashBuffer))
    .map(b => b.toString(16).padStart(2, '0'))
    .join('')
}