<template>
  <div class="page-container-flex">
    <van-nav-bar 
      :title="navTitle" 
      left-text="返回"
      left-arrow
      placeholder 
      @click-left="handleBack"
    />

    <div class="scroll-content">
    <!-- 第一层：选择交易类型 -->
    <div v-if="currentLevel === 0" class="level-container">
      <van-cell-group inset>
        <van-cell
          v-for="type in typeOptions"
          :key="type.value"
          :title="type.label"
          is-link
          @click="handleSelectType(type.value)"
        />
      </van-cell-group>
    </div>

    <!-- 第二层：分类列表 -->
    <div v-else class="level-container">
      <!-- 面包屑导航 -->
      <div class="breadcrumb">
        <van-tag 
          type="primary" 
          closeable 
          style="margin-left: 16px;"
          @close="handleBackToRoot"
        >
          {{ currentTypeName }}
        </van-tag>
      </div>

      <!-- 分类列表 -->
      <van-empty v-if="categories.length === 0" description="暂无分类" />
      
      <van-cell-group v-else inset>
        <van-swipe-cell v-for="category in categories" :key="category.id">
          <van-cell 
            :title="category.name" 
            is-link 
            @click="handleEdit(category)"
          />
          <template #right>
            <van-button 
              square 
              type="danger" 
              text="删除"
              @click="handleDelete(category)"
            />
          </template>
        </van-swipe-cell>
      </van-cell-group>
    </div>

    <!-- 底部安全距离 -->
    <div style="height: calc(80px + env(safe-area-inset-bottom, 0px))"></div>

    <div class="bottom-button">
      <!-- 新增分类按钮 -->
      <van-button 
        type="primary" 
        size="large" 
        icon="plus"
        @click="handleAddCategory"
      >
        新增分类
      </van-button>
    </div>

    <!-- 新增分类对话框 -->
    <van-dialog
      v-model:show="showAddDialog"
      title="新增分类"
      @confirm="handleConfirmAdd"
      @cancel="resetAddForm"
    >
      <van-form ref="addFormRef">
        <van-field
          v-model="addForm.name"
          name="name"
          label="分类名称"
          placeholder="请输入分类名称"
          :rules="[{ required: true, message: '请输入分类名称' }]"
        />
      </van-form>
    </van-dialog>

    <!-- 编辑分类对话框 -->
    <van-dialog
      v-model:show="showEditDialog"
      title="编辑分类"
      show-cancel-button
      @confirm="handleConfirmEdit"
    >
      <van-form ref="editFormRef">
        <van-field
          v-model="editForm.name"
          name="name"
          label="分类名称"
          placeholder="请输入分类名称"
          :rules="[{ required: true, message: '请输入分类名称' }]"
        />
      </van-form>
    </van-dialog>

    <!-- 删除确认对话框 -->
    <van-dialog
      v-model:show="showDeleteConfirm"
      title="删除分类"
      message="删除后无法恢复，确定要删除吗？"
      @confirm="handleConfirmDelete"
    />
    </div>
  </div>
</template>

<script setup>
import { ref, computed, onMounted } from 'vue'
import { useRouter } from 'vue-router'
import { 
  showSuccessToast, 
  showToast, 
  showLoadingToast, 
  closeToast 
} from 'vant'
import {
  getCategoryList,
  createCategory,
  deleteCategory,
  updateCategory
} from '@/api/transactionCategory'

const router = useRouter()

// 交易类型选项
const typeOptions = [
  { value: 0, label: '支出' },
  { value: 1, label: '收入' },
  { value: 2, label: '不计收支' }
]

// 层级状态
const currentLevel = ref(0) // 0=类型选择, 1=分类管理
const currentType = ref(null) // 当前选中的交易类型
const currentTypeName = computed(() => {
  const type = typeOptions.find(t => t.value === currentType.value)
  return type ? type.label : ''
})

// 分类数据
const categories = ref([])

// 编辑对话框
const showAddDialog = ref(false)
const addFormRef = ref(null)
const addForm = ref({
  name: ''
})

// 删除确认
const showDeleteConfirm = ref(false)
const deleteTarget = ref(null)

// 编辑对话框
const showEditDialog = ref(false)
const editFormRef = ref(null)
const editForm = ref({
  id: 0,
  name: ''
})

// 计算导航栏标题
const navTitle = computed(() => {
  if (currentLevel.value === 0) {
    return '编辑分类'
  }
  return currentTypeName.value
})

/**
 * 选择交易类型，进入分类管理
 */
const handleSelectType = async (type) => {
  currentType.value = type
  currentLevel.value = 1
  await loadCategories()
}

/**
 * 加载分类列表
 */
const loadCategories = async () => {
  try {
    showLoadingToast({
      message: '加载中...',
      forbidClick: true,
      duration: 0
    })

    const { success, data } = await getCategoryList(currentType.value)
    if (success) {
      categories.value = data || []
    } else {
      showToast('加载分类失败')
    }
  } catch (error) {
    console.error('加载分类错误:', error)
    showToast('加载分类失败: ' + (error.message || '未知错误'))
  } finally {
    closeToast()
  }
}

/**
 * 返回上一级
 */
const handleBack = () => {
  if (currentLevel.value === 1) {
    currentLevel.value = 0
    currentType.value = null
    categories.value = []
  } else {
    router.back()
  }
}

/**
 * 返回到根目录（类型选择）
 */
const handleBackToRoot = () => {
  currentLevel.value = 0
  currentType.value = null
  categories.value = []
}

/**
 * 新增分类
 */
const handleAddCategory = () => {
  addForm.value = {
    name: ''
  }
  showAddDialog.value = true
}

/**
 * 确认新增
 */
const handleConfirmAdd = async () => {
  try {
    // 表单验证
    await addFormRef.value?.validate()

    showLoadingToast({
      message: '创建中...',
      forbidClick: true,
      duration: 0
    })

    const { success, message } = await createCategory({
      name: addForm.value.name,
      type: currentType.value
    })

    if (success) {
      showSuccessToast('创建成功')
      showAddDialog.value = false
      resetAddForm()
      await loadCategories()
    } else {
      showToast(message || '创建失败')
    }
  } catch (error) {
    console.error('创建失败:', error)
    showToast('创建失败: ' + (error.message || '未知错误'))
  } finally {
    closeToast()
  }
}

/**
 * 编辑分类
 */
const handleEdit = (category) => {
  editForm.value = {
    id: category.id,
    name: category.name
  }
  showEditDialog.value = true
}

/**
 * 确认编辑
 */
const handleConfirmEdit = async () => {
  try {
    await editFormRef.value?.validate()
    
    showLoadingToast({
      message: '保存中...',
      forbidClick: true,
      duration: 0
    })

    const { success, message } = await updateCategory({
      id: editForm.value.id,
      name: editForm.value.name
    })

    if (success) {
      showSuccessToast('保存成功')
      showEditDialog.value = false
      await loadCategories()
    } else {
      showToast(message || '保存失败')
    }
  } catch (error) {
    console.error('保存失败:', error)
    showToast('保存失败: ' + (error.message || '未知错误'))
  } finally {
    closeToast()
  }
}

/**
 * 删除分类
 */
const handleDelete = async (category) => {
  deleteTarget.value = category
  showDeleteConfirm.value = true
}

/**
 * 确认删除
 */
const handleConfirmDelete = async () => {
  if (!deleteTarget.value) return

  try {
    showLoadingToast({
      message: '删除中...',
      forbidClick: true,
      duration: 0
    })

    const { success, message } = await deleteCategory(deleteTarget.value.id)

    if (success) {
      showSuccessToast('删除成功')
      showDeleteConfirm.value = false
      deleteTarget.value = null
      await loadCategories()
    } else {
      showToast(message || '删除失败')
    }
  } catch (error) {
    console.error('删除失败:', error)
    showToast('删除失败: ' + (error.message || '未知错误'))
  } finally {
    closeToast()
  }
}

/**
 * 重置新增表单
 */
const resetAddForm = () => {
  addForm.value = {
    name: ''
  }
}

onMounted(() => {
  // 初始化时显示类型选择
  currentLevel.value = 0
})
</script>


<style scoped>
.level-container {
  min-height: calc(100vh - 50px);
  margin-top: 16px;
}

.breadcrumb {
  padding: 8px 0;
}

.breadcrumb .van-tag {
  cursor: pointer;
}

/* 深色模式 */
@media (prefers-color-scheme: dark) {
  .level-container {
    background: #1a1a1a;
  }
}

/* 设置页面容器背景色 */
:deep(.van-nav-bar) {
  background: transparent !important;
}
</style>
