/**
 * 页面卸载清理注册表（Task 89）。
 *
 * 统一管理页面级需在卸载时释放的资源：
 * - 临时 URL：createObjectURL 产生的 blob URL 通过 revokeUrl 释放；
 * - 请求：AbortController 在卸载时 abort（registerRequestController）；
 * - timer：dispose 时委托 hooks.clearTimers()（配合 categorized-timers
 *   的 clearScope 全量清理）。
 *
 * dispose 幂等：第二次及以后的调用不再重复清理；dispose 后注册被拒绝
 * 并计数。revokeUrl 抛错不中断其余条目的清理；maxTrackedUrls（默认不
 * 限）用于限制同一页面累计注册的 URL 数量，超过时只保留最近注册的。
 */
export interface PageCleanupRegistryHooks {
  /** 卸载时清空全部 timer */
  clearTimers: () => void
  /** 卸载时释放单个 blob URL */
  revokeUrl: (url: string) => void
}

export interface PageCleanupRegistryOptions {
  /** 累计跟踪的 URL 上限（0 表示不限制），超过时只保留最近注册的 */
  maxTrackedUrls?: number
}

export function createPageCleanupRegistry(
  hooks: PageCleanupRegistryHooks,
  options: PageCleanupRegistryOptions = {},
) {
  if (typeof hooks?.clearTimers !== 'function') {
    throw new Error('clearTimers 必须是函数')
  }
  if (typeof hooks?.revokeUrl !== 'function') {
    throw new Error('revokeUrl 必须是函数')
  }
  const maxTrackedUrls = options.maxTrackedUrls ?? 0
  const urls: string[] = []
  const controllers: AbortController[] = []
  let disposed = false
  let disposeCount = 0
  let rejectedCount = 0

  function registerObjectUrl(url: string): string {
    if (disposed) {
      rejectedCount += 1
      return url
    }
    if (!url) return url
    urls.push(url)
    if (maxTrackedUrls > 0 && urls.length > maxTrackedUrls) {
      urls.splice(0, urls.length - maxTrackedUrls)
    }
    return url
  }

  function registerRequestController(controller: AbortController) {
    if (disposed) {
      rejectedCount += 1
      return
    }
    controllers.push(controller)
  }

  function dispose(): number {
    if (disposed) {
      return 0
    }
    disposed = true
    let released = 0
    for (const url of urls) {
      try {
        hooks.revokeUrl(url)
      } catch {
        /* 单个 URL 释放失败不中断其余清理 */
      }
      released += 1
    }
    urls.length = 0
    for (const controller of controllers) {
      try {
        controller.abort()
      } catch {
        /* abort 失败不中断其余清理 */
      }
      released += 1
    }
    controllers.length = 0
    hooks.clearTimers()
    released += 1
    disposeCount += 1
    return released
  }

  return {
    get trackedUrlCount() {
      return urls.length
    },
    get requestCount() {
      return controllers.length
    },
    get disposed() {
      return disposed
    },
    get disposeCount() {
      return disposeCount
    },
    get rejectedCount() {
      return rejectedCount
    },
    registerObjectUrl,
    registerRequestController,
    dispose,
  }
}

export type PageCleanupRegistry = ReturnType<typeof createPageCleanupRegistry>