import sqlite3 from 'sqlite3'
import path from 'path'
import crypto from 'crypto'

export interface ApiKey {
  id: number
  key_hash: string
  name: string
  permissions: string[]
  rate_limit: number
  is_active: boolean
  last_used?: string
  created_at: string
}

export function generateApiKey(): string {
  return 'ak_' + crypto.randomBytes(32).toString('hex')
}

export function hashApiKey(key: string): string {
  return crypto.createHash('sha256').update(key).digest('hex')
}

export async function validateApiKey(key: string): Promise<ApiKey | null> {
  if (!key || !key.startsWith('ak_')) return null
  
  const keyHash = hashApiKey(key)
  const dbPath = path.join(process.cwd(), 'database', 'antihoax.db')
  const db = new sqlite3.Database(dbPath)
  
  try {
    const apiKey = await new Promise<ApiKey | null>((resolve, reject) => {
      db.get(
        'SELECT * FROM api_keys WHERE key_hash = ? AND is_active = 1',
        [keyHash],
        (err, row: any) => {
          if (err) reject(err)
          else if (row) {
            resolve({
              ...row,
              permissions: row.permissions ? JSON.parse(row.permissions) : []
            })
          } else {
            resolve(null)
          }
        }
      )
    })
    
    if (apiKey) {
      // Update last_used timestamp
      await new Promise<void>((resolve, reject) => {
        db.run(
          'UPDATE api_keys SET last_used = datetime("now") WHERE id = ?',
          [apiKey.id],
          (err) => {
            if (err) reject(err)
            else resolve()
          }
        )
      })
    }
    
    return apiKey
  } catch (error) {
    console.error('API key validation error:', error)
    return null
  } finally {
    db.close()
  }
}

export function hasPermission(apiKey: ApiKey, permission: string): boolean {
  return apiKey.permissions.includes('*') || apiKey.permissions.includes(permission)
}

export const ApiPermissions = {
  READ_SOURCES: 'sources:read',
  WRITE_SOURCES: 'sources:write', 
  READ_REPORTS: 'reports:read',
  WRITE_REPORTS: 'reports:write',
  ADMIN: '*'
} as const