// utils/flowLoading.ts
/**
 * @author easycreatecode.com
 * @created 2025-03-05
 * @updated 2025-03-08
 * @version 1.2.0
 * @description 基于Element Plus的流程加载控制器，支持链式操作和动态文本更新，如果使用请保留作者信息
 */
import { ElLoading } from "element-plus"
import type { Component, Ref } from "vue"
import { isRef, unref } from "vue"
import type { LoadingOptions } from 'element-plus/es/components/loading/src/types'

// 1. 明确控制器类型接口
interface LoadingController {
  step: (text: string | Ref<string>) => LoadingController
  end: () => void
}

type CustomLoadingOptions = Omit<LoadingOptions, 'text'> & {
  text?: string | Ref<string>
  spinner?: string | Component
}

const DEFAULT_CONFIG: CustomLoadingOptions = {
  lock: true,
  text: '',
  //background: 'rgba(0, 199, 255, 0.3)',
  background: 'rgba(94, 158, 214, 0.12)', // 景德镇青花色
  //spinner: 'circle-check'
  //spinner: 'el-icon-potato',
  spinner: 'el-icon-loading',
}

class FlowLoadingManager {
  private instance: ReturnType<typeof ElLoading.service> | null = null

  // 2. 统一返回类型
  start(options?: string | Ref<string> | CustomLoadingOptions): LoadingController {
    try {
      if (this.instance) {
        console.warn('Existing loading instance detected')
        return this.createController()
      }

      const resolved = this.normalizeOptions(options)
      this.validateConfig(resolved)
      
      this.instance = ElLoading.service(resolved as LoadingOptions)
      return this.createController()
    } catch (e) {
      console.error('Loading initialization failed:', e)
      return this.createController(true) // 传入错误标记
    }
  }

  private normalizeOptions(options?: string | Ref<string> | CustomLoadingOptions): CustomLoadingOptions {
    const baseConfig = { ...DEFAULT_CONFIG }
    
    if (!options) return baseConfig
    
    if (typeof options === 'string' || isRef(options)) {
      return { 
        ...baseConfig,
        text: unref(options)
      }
    }
    
    return {
      ...baseConfig,
      ...options,
      text: options.text ? unref(options.text) : baseConfig.text
    }
  }

  private validateConfig(config: CustomLoadingOptions) {
    if (config.spinner && typeof config.spinner !== 'string') {
      console.warn('Custom spinner components require proper registration')
    }
    
    if (typeof config.text !== 'string') {
      throw new Error('Loading text must be a string')
    }
  }

  // 3. 增强控制器创建方法
  private createController(isError = false): LoadingController {
    return {
      step: (text: string | Ref<string>) => {
        if (!isError && this.instance) {
          this.instance.setText(unref(text))
        }
        return this.createController(isError) // 保持链式调用
      },
      end: () => {
        if (!isError) {
          this.instance?.close()
        }
        this.instance = null
      }
    }
  }
}

export const flowLoading = new FlowLoadingManager()