const GRAPHQL_ENDPOINT = '/api/graphql'

// GraphQL请求函数
async function graphqlRequest(query, variables = {}) {
  const response = await fetch(GRAPHQL_ENDPOINT, {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
    },
    body: JSON.stringify({
      query,
      variables,
    }),
  })

  if (!response.ok) {
    const errorText = await response.text();
    throw new Error(`HTTP error! status: ${response.status}, body: ${errorText}`)
  }

  const result = await response.json()
  
  if (result.errors) {
    throw new Error(result.errors.map(e => e.message).join('\n'))
  }

  return result.data
}

// --- GraphQL Query Strings ---

const GET_REGIONS = `
  query GetRegions($name: String, $state: Int, $page: Int!, $size: Int!) {
    regions(name: $name, state: $state, page: $page, size: $size) {
      content { id name pid code level leafFlag fullPath state createTime createUserId updateTime updateUserId version }
      totalElements totalPages currentPage pageSize
    }
  }
`

const GET_ALL_REGIONS = `
  query GetAllRegions {
    allRegions { id name pid code level leafFlag fullPath state createTime }
  }
`

const GET_REGION = `
  query GetRegion($id: ID!) {
    region(id: $id) { id name pid code level leafFlag fullPath state createTime createUserId updateTime updateUserId version }
  }
`

const GET_PROVINCES = `
  query GetProvinces {
    provinces { id name pid code level state }
  }
`

const GET_CITIES = `
  query GetCities($provinceId: ID!) {
    cities(provinceId: $provinceId) { id name pid code level state }
  }
`

const GET_DISTRICTS = `
  query GetDistricts($cityId: ID!) {
    districts(cityId: $cityId) { id name pid code level state }
  }
`

const GET_REGION_CHILDREN = `
  query GetRegionChildren($parentId: ID!) {
    regionChildren(parentId: $parentId) { id name pid code level leafFlag state }
  }
`

const SAVE_REGION = `
  mutation SaveRegion($input: RegionInput!) {
    saveRegion(input: $input) { id name pid code level leafFlag fullPath state createTime updateTime version }
  }
`

const DELETE_REGION = `
  mutation DeleteRegion($id: ID!) {
    deleteRegion(id: $id)
  }
`

const TOGGLE_REGION_STATE = `
  mutation ToggleRegionState($id: ID!) {
    toggleRegionState(id: $id) { id name state updateTime }
  }
`

// --- API Functions ---

export const RegionApi = {
  getRegions: async (name, state, page, size) => {
    const data = await graphqlRequest(GET_REGIONS, { name, state, page, size });
    return data.regions;
  },
  getAllRegions: async () => {
    const data = await graphqlRequest(GET_ALL_REGIONS);
    return data.allRegions;
  },
  getRegion: async (id) => {
    const data = await graphqlRequest(GET_REGION, { id });
    return data.region;
  },
  getProvinces: async () => {
    const data = await graphqlRequest(GET_PROVINCES);
    return data.provinces || [];
  },
  getCities: async (provinceId) => {
    const data = await graphqlRequest(GET_CITIES, { provinceId });
    return data.cities || [];
  },
  getDistricts: async (cityId) => {
    const data = await graphqlRequest(GET_DISTRICTS, { cityId });
    return data.districts || [];
  },
  getChildren: async (parentId) => {
    const data = await graphqlRequest(GET_REGION_CHILDREN, { parentId });
    return data.regionChildren;
  },
  saveRegion: async (input) => {
    const data = await graphqlRequest(SAVE_REGION, { input });
    return data.saveRegion;
  },
  deleteRegion: async (id) => {
    const data = await graphqlRequest(DELETE_REGION, { id });
    return data.deleteRegion;
  },
  toggleRegionState: async (id) => {
    const data = await graphqlRequest(TOGGLE_REGION_STATE, { id });
    return data.toggleRegionState;
  }
}