import { ref, computed, onMounted, nextTick, type Ref } from 'vue'
import { useRoute } from 'vue-router'
import type { TableInstance } from 'element-plus'

export interface ColumnConfig {
  prop?: string
  label: string
  fixed?: boolean | 'left' | 'right'
  alwaysShow?: boolean
  [key: string]: any
}

/**
 * 表格列控制通用 Composable
 * 简化 TableColumnControl 组件的使用
 * 
 * @param options 配置选项
 * @returns 返回列控制相关的响应式数据和方法
 */
export function useTableColumnControl(options?: {
  /** 表格 ref（用于自动提取列配置） */
  tableRef?: Ref<TableInstance | undefined>
  /** 手动配置的列（如果提供了 tableRef 则忽略） */
  columns?: ColumnConfig[]
  /** localStorage 存储的 key（可选，默认根据路由自动生成） */
  storageKey?: string
  /** 默认显示的列（prop 或 label 数组） */
  defaultVisible?: string[]
  /** 始终显示的列（prop 或 label 数组） */
  alwaysShow?: string[]
}) {
  const route = useRoute()
  
  // 根据路由自动生成 storageKey
  const getStorageKey = (suffix: string = ''): string => {
    if (options?.storageKey) {
      return options.storageKey + (suffix ? `-${suffix}` : '')
    }
    const routePath = route.path.replace(/^\//, '').replace(/\//g, '-')
    return `table-columns-${routePath}${suffix ? `-${suffix}` : ''}`
  }
  
  // 可见列
  const visibleColumns = ref<string[]>([])
  
  // 列排序
  const columnOrder = ref<string[]>([])
  
  // 列配置（手动配置或从表格提取）
  const tableColumns = computed(() => {
    return options?.columns || []
  })
  
  // 加载保存的配置
  const loadSavedConfig = () => {
    const storageKey = getStorageKey()
    const saved = localStorage.getItem(storageKey)
    
    if (saved) {
      try {
        const savedColumns = JSON.parse(saved)
        const validColumns = tableColumns.value
          .filter(col => !col.alwaysShow && !col.fixed)
          .map(col => col.prop || col.label)
        const filteredSaved = savedColumns.filter((col: string) => validColumns.includes(col))
        
        if (filteredSaved.length > 0) {
          visibleColumns.value = filteredSaved
        } else if (options?.defaultVisible && options.defaultVisible.length > 0) {
          visibleColumns.value = options.defaultVisible
        } else {
          visibleColumns.value = validColumns
        }
      } catch (e) {
        console.error('解析列配置失败:', e)
        visibleColumns.value = options?.defaultVisible || tableColumns.value
          .filter(col => !col.alwaysShow && !col.fixed)
          .map(col => col.prop || col.label)
      }
    } else {
      visibleColumns.value = options?.defaultVisible || tableColumns.value
        .filter(col => !col.alwaysShow && !col.fixed)
        .map(col => col.prop || col.label)
    }
    
    // 加载列排序配置
    const orderKey = getStorageKey('order')
    const savedOrder = localStorage.getItem(orderKey)
    if (savedOrder) {
      try {
        const parsedOrder = JSON.parse(savedOrder)
        const validColumns = tableColumns.value
          .filter(col => !col.alwaysShow && !col.fixed)
          .map(col => col.prop || col.label)
        columnOrder.value = parsedOrder.filter((key: string) => validColumns.includes(key))
        
        // 添加新列到排序列表末尾
        validColumns.forEach(key => {
          if (!columnOrder.value.includes(key)) {
            columnOrder.value.push(key)
          }
        })
      } catch (e) {
        console.error('解析列排序失败:', e)
        columnOrder.value = tableColumns.value
          .filter(col => !col.alwaysShow && !col.fixed)
          .map(col => col.prop || col.label)
      }
    } else {
      columnOrder.value = tableColumns.value
        .filter(col => !col.alwaysShow && !col.fixed)
        .map(col => col.prop || col.label)
    }
  }
  
  // 保存列配置
  const saveColumnConfig = (columns: string[]) => {
    visibleColumns.value = columns
    const storageKey = getStorageKey()
    const selectableColumns = columns.filter(col => {
      const column = tableColumns.value.find(c => (c.prop || c.label) === col)
      return column && !column.alwaysShow && !column.fixed
    })
    localStorage.setItem(storageKey, JSON.stringify(selectableColumns))
  }
  
  // 保存列排序
  const saveColumnOrder = (order: string[]) => {
    columnOrder.value = order
    const orderKey = getStorageKey('order')
    localStorage.setItem(orderKey, JSON.stringify(order))
  }
  
  // 检查列是否可见
  const checkColumnVisible = (prop: string): boolean => {
    if (visibleColumns.value.length === 0) {
      return true
    }
    return visibleColumns.value.includes(prop)
  }
  
  // 初始化
  onMounted(() => {
    nextTick(() => {
      loadSavedConfig()
    })
  })
  
  return {
    visibleColumns,
    columnOrder,
    tableColumns,
    checkColumnVisible,
    saveColumnConfig,
    saveColumnOrder,
    loadSavedConfig,
    getStorageKey
  }
}