import { NextResponse } from 'next/server'
import { ZodError, type z } from 'zod'

/** Throwable API error with HTTP status code */
export class ApiError extends Error {
  status: number
  constructor(message: string, status: number = 400) {
    super(message)
    this.name = 'ApiError'
    this.status = status
  }
}

/** Standard success response: { ok: true, ...data } */
export function apiOk(data?: Record<string, unknown>) {
  return NextResponse.json({ ok: true, ...data })
}

/** Standard error response: { error: message } with given status */
export function apiError(message: string, status: number = 400) {
  return NextResponse.json({ error: message }, { status })
}

/** Validation error from Zod: { error: fieldErrors } with 400 */
export function apiValidationError(zodError: z.ZodError) {
  return NextResponse.json({ error: zodError.flatten().fieldErrors }, { status: 400 })
}

/** Centralized error handler for API routes */
export function handleApiError(error: unknown): Response {
  if (error instanceof ApiError) {
    return apiError(error.message, error.status)
  }
  if (error instanceof ZodError) {
    return apiValidationError(error)
  }
  // Prisma P2025 "Record not found"
  if (
    error instanceof Error &&
    (error.constructor.name === 'PrismaClientKnownRequestError' ||
      error.name === 'PrismaClientKnownRequestError') &&
    (error as Error & { code?: string }).code === 'P2025'
  ) {
    return apiError('Not found', 404)
  }
  console.error(
    '[API error]',
    error instanceof Error ? { message: error.message, name: error.name } : error,
  )
  return apiError('Internal server error', 500)
}