import {
  getApprovalTemplateDetail,
  listApprovalTemplate,
  TEMPLATE_TYPE_CUSTOM,
} from "@/api/officeProcessAutomation/approvalTemplate.js";
import {
  approveApprovalInstance,
  deleteApprovalInstance,
  listApprovalInstancePage,
  saveApprovalInstance,
  updateApprovalInstance,
} from "@/api/officeProcessAutomation/approvalInstance.js";
import useUserStore from "@/store/modules/user";
import { Search } from "@element-plus/icons-vue";
import { ElMessage, ElMessageBox } from "element-plus";
import { computed, reactive, ref } from "vue";
import {
  fetchBusinessTypeOptions,
  formatDisplayTime,
  mapEnabledFromApi,
  mapTemplateFromApi,
  unwrapTemplateDetail,
  unwrapTemplateList,
} from "../approve-template/approveTemplateConstants.js";
import { buildSubmitTemplateFromRow } from "../approve-template/formConfigUtils.js";
import {
  APPROVAL_TYPE_OPTIONS,
  approvalStatusLabel,
  approvalStatusTagType,
  approvalTypeLabel,
  buildApprovalInstanceListParams,
  buildApproveInstanceDto,
  buildEditFormFromInstanceRow,
  buildInstanceDto,
  clearLegacyApproveListStorage,
  createEmptySubmitForm,
  mapInstanceFromApi,
  mapSubmitTemplateCard,
  matchBusinessTypeValue,
  validateSubmitFlowNodes,
  unwrapInstancePage,
} from "./approveListConstants.js";

export function useApproveList() {
  clearLegacyApproveListStorage();
  const userStore = useUserStore();

  const tableData = ref([]);
  const submitBusinessTypeOptions = ref([]);
  const allSubmitTemplates = ref([]);
  const selectedBusinessType = ref("");
  const submitTemplatesLoading = ref(false);

  const submitTemplateCards = computed(() => {
    if (selectedBusinessType.value == null || selectedBusinessType.value === "") return [];
    return allSubmitTemplates.value.filter((card) =>
      matchBusinessTypeValue(card.businessType, selectedBusinessType.value)
    );
  });

  const searchForm = reactive({
    approvalType: "",
    applicantKeyword: "",
    createTimeRange: [],
  });

  const tableLoading = ref(false);
  const page = reactive({ current: 1, size: 10, total: 0 });

  const detailDialog = reactive({ visible: false });
  const detailRow = ref({});

  const approveDialog = reactive({ visible: false, row: null });
  const approveOpinion = ref("");
  const approveSubmitting = ref(false);

  const submitDialog = reactive({ visible: false, step: 1, mode: "add" });
  const submitEditRow = ref(null);
  const submitForm = reactive(createEmptySubmitForm(""));
  const submitFormRef = ref();
  const submitSaving = ref(false);

  const isSubmitEdit = computed(() => submitDialog.mode === "edit");
  const submitDialogTitle = computed(() => {
    if (submitDialog.mode === "edit") {
      return `修改${activeTemplate.value?.label || submitForm.templateName || "审批"}`;
    }
    if (submitDialog.step === 1) return "选择模板类型";
    if (submitDialog.step === 2) return `选择审批模板${businessTypeLabel(selectedBusinessType.value) ? `（${businessTypeLabel(selectedBusinessType.value)}）` : ""}`;
    return `提交${activeTemplate.value?.label || "审批"}`;
  });

  const selectedBusinessTypeLabel = computed(() => businessTypeLabel(selectedBusinessType.value));

  function businessTypeLabel(type) {
    if (type == null || type === "") return "";
    const hit = submitBusinessTypeOptions.value.find((x) => matchBusinessTypeValue(x.value, type));
    return hit?.label || "";
  }

  function countTemplatesByBusinessType(type) {
    return allSubmitTemplates.value.filter((card) => matchBusinessTypeValue(card.businessType, type)).length;
  }

  const activeTemplate = computed(() => submitForm.templateSnapshot || null);

  /** 填报项定义（新增/修改与 formConfig 一致） */
  const submitFormFields = computed(() => {
    const tplFields = activeTemplate.value?.fields;
    if (tplFields?.length) return tplFields;
    return submitForm.formFieldDefs || [];
  });

  const submitFormRules = computed(() => {
    const rules = {
      templateKey: [{ required: true, message: "请选择审批类型", trigger: "change" }],
    };
    submitFormFields.value.forEach((f) => {
      if (!f.required) return;
      if (f.type === "number") {
        rules[`formPayload.${f.key}`] = [{ required: true, message: `请填写${f.label}`, trigger: "blur" }];
      } else if (f.type === "datetimerange") {
        rules[`formPayload.${f.key}`] = [{ required: true, message: `请选择${f.label}`, trigger: "change" }];
      } else {
        rules[`formPayload.${f.key}`] = [{ required: true, message: `请填写${f.label}`, trigger: "blur" }];
      }
    });
    return rules;
  });

  const tableColumn = ref([
    { label: "申请人编号", prop: "applicantNo", width: 110 },
    { label: "申请人名称", prop: "applicantName", minWidth: 100 },
    { label: "业务类型", prop: "businessName", minWidth: 120 },
    {
      label: "审批类型",
      prop: "approvalType",
      minWidth: 140,
      dataType: "slot",
      slot: "approveType",
    },
    {
      label: "待我审批",
      prop: "unread",
      width: 90,
      align: "center",
      formatData: (v) => (v ? "是" : "否"),
    },
    {
      label: "审批状态",
      prop: "approvalStatus",
      width: 100,
      dataType: "tag",
      formatData: (v) => approvalStatusLabel(v),
      formatType: (v) => approvalStatusTagType(v),
    },
    {
      label: "创建时间",
      prop: "createTime",
      width: 170,
      formatData: (v) => formatDisplayTime(v),
    },
    {
      dataType: "action",
      label: "操作",
      align: "center",
      fixed: "right",
      width: 240,
      operation: [
        { name: "详情", type: "text", clickFun: (row) => openDetail(row) },
        {
          name: "修改",
          type: "text",
          disabled: (row) => row.approvalStatus !== "pending",
          clickFun: (row) => openEditDialog(row),
        },
        {
          name: "审批",
          type: "text",
          disabled: (row) => row.approvalStatus !== "pending" || !row.isApprove,
          clickFun: (row) => openApprove(row),
        },
        {
          name: "删除",
          type: "danger",
          clickFun: (row) => removeInstance(row),
        },
      ],
    },
  ]);

  async function fetchApprovalList() {
    tableLoading.value = true;
    try {
      const res = await listApprovalInstancePage(
        buildApprovalInstanceListParams({ page, searchForm })
      );
      const { records, total } = unwrapInstancePage(res);
      tableData.value = records.map(mapInstanceFromApi);
      page.total = total;
    } catch {
      tableData.value = [];
      page.total = 0;
      ElMessage.error("审批列表加载失败");
    } finally {
      tableLoading.value = false;
    }
  }

  async function loadSubmitTemplates() {
    submitTemplatesLoading.value = true;
    try {
      const [typeOptions, customRes] = await Promise.all([
        fetchBusinessTypeOptions(),
        listApprovalTemplate(TEMPLATE_TYPE_CUSTOM),
      ]);
      submitBusinessTypeOptions.value = typeOptions;
      allSubmitTemplates.value = unwrapTemplateList(customRes)
        .filter((row) => mapEnabledFromApi(row.enabled))
        .map(mapSubmitTemplateCard);
    } catch {
      submitBusinessTypeOptions.value = [];
      allSubmitTemplates.value = [];
      ElMessage.error("加载审批模板失败");
    } finally {
      submitTemplatesLoading.value = false;
    }
  }

  function handleQuery() {
    page.current = 1;
    fetchApprovalList();
  }

  function resetSearch() {
    searchForm.approvalType = "";
    searchForm.applicantKeyword = "";
    searchForm.createTimeRange = [];
    handleQuery();
  }

  function pagination({ page: p, limit }) {
    page.current = p;
    page.size = limit;
    fetchApprovalList();
  }

  function openDetail(row) {
    detailRow.value = { ...row };
    detailDialog.visible = true;
  }

  function openApprove(row) {
    approveDialog.row = { ...row };
    approveOpinion.value = "";
    approveDialog.visible = true;
  }

  function resetSubmitDialogState() {
    submitDialog.mode = "add";
    submitDialog.step = 1;
    selectedBusinessType.value = "";
    submitEditRow.value = null;
    Object.assign(submitForm, createEmptySubmitForm(""));
  }

  function openSubmitDialog() {
    resetSubmitDialogState();
    submitDialog.visible = true;
    loadSubmitTemplates();
  }

  function openEditDialog(row) {
    if (row?.approvalStatus !== "pending") {
      ElMessage.warning("仅审核中的审批可修改");
      return;
    }
    if (!row?.id) {
      ElMessage.warning("无法修改：缺少审批实例 ID");
      return;
    }
    submitDialog.mode = "edit";
    submitDialog.step = 3;
    submitEditRow.value = { ...row };
    Object.assign(submitForm, buildEditFormFromInstanceRow(row));
    submitDialog.visible = true;
  }

  async function onTemplatePick(card) {
    if (!card?.id) return;
    submitTemplatesLoading.value = true;
    try {
      const res = await getApprovalTemplateDetail(card.id);
      const mapped = mapTemplateFromApi(unwrapTemplateDetail(res));
      const tpl = {
        ...buildSubmitTemplateFromRow(mapped),
        templateId: mapped.id,
      };
      const base = createEmptySubmitForm(String(card.id), tpl, mapped.flowNodes);
      Object.assign(submitForm, {
        ...base,
        templateName: mapped.templateName || tpl.label || "",
        businessType: mapped.businessType ?? card.businessType ?? selectedBusinessType.value,
        templateSnapshot: tpl,
        formFieldDefs: tpl.fields || [],
      });
      submitDialog.step = 3;
    } catch {
      ElMessage.error("加载模板详情失败");
    } finally {
      submitTemplatesLoading.value = false;
    }
  }

  function onBusinessTypePick(type) {
    if (!countTemplatesByBusinessType(type)) {
      ElMessage.warning("该类型下暂无可用审批模板");
      return;
    }
    selectedBusinessType.value = type;
    submitDialog.step = 2;
  }

  function backToBusinessTypePick() {
    selectedBusinessType.value = "";
    submitDialog.step = 1;
  }

  function backToTemplatePick() {
    submitDialog.step = 2;
  }

  async function submitInstanceForm() {
    if (submitDialog.mode === "edit") return submitEditApproval();
    return submitNewApproval();
  }

  async function submitNewApproval() {
    if (!submitFormRef.value) return false;
    try {
      await submitFormRef.value.validate();
    } catch {
      return false;
    }
    if (!activeTemplate.value) return false;
    const flowCheck = validateSubmitFlowNodes(submitForm.flowNodes);
    if (!flowCheck.ok) {
      ElMessage.warning(flowCheck.message);
      return false;
    }
    if (!submitForm.templateId) {
      ElMessage.warning("缺少模板 ID，无法提交");
      return false;
    }
    if (submitSaving.value) return false;
    submitSaving.value = true;
    try {
      await saveApprovalInstance(
        buildInstanceDto({
          submitForm,
          activeTemplate: activeTemplate.value,
          userStore,
          flowNodes: flowCheck.nodes,
        })
      );
      submitDialog.visible = false;
      page.current = 1;
      await fetchApprovalList();
      return true;
    } catch {
      return false;
    } finally {
      submitSaving.value = false;
    }
  }

  async function submitEditApproval() {
    if (!submitFormRef.value) return false;
    try {
      await submitFormRef.value.validate();
    } catch {
      return false;
    }
    if (!activeTemplate.value) return false;
    const flowCheck = validateSubmitFlowNodes(submitForm.flowNodes);
    if (!flowCheck.ok) {
      ElMessage.warning(flowCheck.message);
      return false;
    }
    if (!submitForm.instanceId) {
      ElMessage.warning("缺少审批实例 ID，无法保存");
      return false;
    }
    if (submitSaving.value) return false;
    submitSaving.value = true;
    try {
      await updateApprovalInstance(
        buildInstanceDto({
          submitForm,
          activeTemplate: activeTemplate.value,
          flowNodes: flowCheck.nodes,
          existingRow: submitEditRow.value,
        })
      );
      submitDialog.visible = false;
      await fetchApprovalList();
      if (detailDialog.visible && detailRow.value?.id === submitForm.instanceId) {
        const hit = tableData.value.find((r) => r.id === submitForm.instanceId);
        if (hit) detailRow.value = { ...hit };
        else detailDialog.visible = false;
      }
      return true;
    } catch {
      return false;
    } finally {
      submitSaving.value = false;
    }
  }

  async function removeInstance(row) {
    if (row?.id == null || row.id === "") {
      ElMessage.warning("无法删除：缺少审批实例 ID");
      return;
    }
    const title = row.title || row.templateName || row.instanceNo || "该审批";
    try {
      await ElMessageBox.confirm(
        `确定要删除审批「${title}」吗？删除后不可恢复。`,
        "删除确认",
        {
          type: "warning",
          confirmButtonText: "确定删除",
          cancelButtonText: "取消",
          distinguishCancelAndClose: true,
          autofocus: false,
        }
      );
    } catch {
      return;
    }
    try {
      await deleteApprovalInstance([row.id]);
      ElMessage.success("删除成功");
      if (detailDialog.visible && detailRow.value?.id === row.id) {
        detailDialog.visible = false;
      }
      if (approveDialog.visible && approveDialog.row?.id === row.id) {
        approveDialog.visible = false;
      }
      await fetchApprovalList();
    } catch {
      /* 错误由拦截器提示 */
    }
  }

  async function submitApprove(result) {
    const row = approveDialog.row;
    if (!row?.id) return { ok: false };
    if (result === "rejected" && !(approveOpinion.value || "").trim()) {
      return { needOpinion: true };
    }
    if (approveSubmitting.value) return { ok: false };
    approveSubmitting.value = true;
    try {
      await approveApprovalInstance(
        buildApproveInstanceDto(row, result, approveOpinion.value)
      );
      approveDialog.visible = false;
      await fetchApprovalList();
      if (detailDialog.visible && detailRow.value?.id === row.id) {
        const hit = tableData.value.find((r) => r.id === row.id);
        if (hit) detailRow.value = { ...hit };
        else detailDialog.visible = false;
      }
      return { ok: true, result };
    } catch {
      ElMessage.error("审批操作失败");
      return { ok: false };
    } finally {
      approveSubmitting.value = false;
    }
  }

  function approvalActionLabel(result) {
    if (result === "approved") return "通过";
    if (result === "rejected") return "驳回";
    return "待处理";
  }

  return {
    Search,
    APPROVAL_TYPE_OPTIONS,
    approvalTypeLabel,
    approvalStatusLabel,
    approvalStatusTagType,
    approvalActionLabel,
    searchForm,
    tableLoading,
    page,
    tableData,
    tableColumn,
    detailDialog,
    detailRow,
    approveDialog,
    approveOpinion,
    approveSubmitting,
    submitDialog,
    isSubmitEdit,
    submitDialogTitle,
    submitForm,
    submitFormRef,
    submitSaving,
    activeTemplate,
    submitFormFields,
    submitFormRules,
    submitBusinessTypeOptions,
    submitTemplateCards,
    selectedBusinessType,
    selectedBusinessTypeLabel,
    businessTypeLabel,
    countTemplatesByBusinessType,
    submitTemplatesLoading,
    handleQuery,
    resetSearch,
    pagination,
    resetSubmitDialogState,
    openSubmitDialog,
    openEditDialog,
    onBusinessTypePick,
    onTemplatePick,
    backToBusinessTypePick,
    backToTemplatePick,
    submitInstanceForm,
    submitNewApproval,
    submitApprove,
    openDetail,
    openApprove,
    fetchApprovalList,
  };
}