diff --git a/src/utils/api.js b/src/utils/api.js
index 70e3df3..a160eae 100644
--- a/src/utils/api.js
+++ b/src/utils/api.js
@@ -773,6 +773,11 @@ export const contractAPI = {
       flow_instance_id: flowInstanceId,
       ...data
     }),
+  simulateFromFlow: (flowInstanceId, settings) =>
+    request.post('/budget/contracts/simulate-from-oa', {
+      flow_instance_id: flowInstanceId,
+      settings
+    }),
   getPendingConversions: (params) => request.get('/budget/contracts/pending-conversions', params),
   batchImport: (data) => request.post('/budget/contracts/batch-import', data),
   previewAttachmentMatch: (data) => request.post('/budget/contracts/preview-attachment-match', data),
@@ -835,6 +840,7 @@ export const contractSettingsAPI = {
   getOaModels: () => request.get('/budget/contract-settings/oa-models'),
   getOaSubModels: () => request.get('/budget/contract-settings/oa-sub-models'),
   getOaFields: (params) => request.get('/budget/contract-settings/oa-fields', params),
+  getOaFlows: (params) => request.get('/budget/contract-settings/oa-flows', params),
   getBudgetFields: () => request.get('/budget/contract-settings/budget-fields')
 }
 
diff --git a/src/views/payment/ContractManagement.vue b/src/views/payment/ContractManagement.vue
index 287a265..f51ce80 100644
--- a/src/views/payment/ContractManagement.vue
+++ b/src/views/payment/ContractManagement.vue
@@ -182,14 +182,14 @@
         <el-table-column prop="remark" label="备注" min-width="150" show-overflow-tooltip />
         <el-table-column prop="attachment" label="附件" width="120">
           <template #default="{ row }">
-            <template v-if="row.attachment_id">
+            <template v-if="getEffectiveAttachment(row)">
               <el-link 
                 v-if="getAttachmentUrl(row)" 
                 :href="getAttachmentUrl(row)" 
                 target="_blank" 
                 type="primary"
               >
-                {{ row.attachment?.original_name || row.attachment?.name || '查看' }}
+                {{ getAttachmentName(row) }}
               </el-link>
               <span v-else style="color: #909399;">附件加载中...</span>
             </template>
@@ -449,6 +449,21 @@
               <div class="el-upload__tip">只能上传 JPG/PNG/PDF/DOC/DOCX/XLS/XLSX 格式的文件，且不超过 10MB</div>
             </template>
           </el-upload>
+          <div v-if="inferredAttachmentInfo" class="oa-inferred-attachment">
+            <div class="oa-inferred-attachment__title">当前附件由 OA 合同流程映射推导，合同本身尚未保存附件。</div>
+            <el-link
+              v-if="getAttachmentUrl({ effective_attachment: inferredAttachmentInfo.attachment })"
+              :href="getAttachmentUrl({ effective_attachment: inferredAttachmentInfo.attachment })"
+              target="_blank"
+              type="primary"
+            >
+              {{ getAttachmentName({ effective_attachment: inferredAttachmentInfo.attachment }) }}
+            </el-link>
+            <span v-else>{{ getAttachmentName({ effective_attachment: inferredAttachmentInfo.attachment }) }}</span>
+            <span v-if="inferredAttachmentInfo.meta?.flow_no || inferredAttachmentInfo.meta?.flow_title" class="oa-inferred-attachment__meta">
+              来源：{{ [inferredAttachmentInfo.meta?.flow_no, inferredAttachmentInfo.meta?.flow_title].filter(Boolean).join(' / ') }}
+            </span>
+          </div>
         </el-form-item>
 
         <el-divider content-position="left">付款计划</el-divider>
@@ -578,14 +593,14 @@
           </el-descriptions-item>
           <el-descriptions-item label="备注" :span="2">{{ viewData.remark || '-' }}</el-descriptions-item>
           <el-descriptions-item label="附件" :span="2">
-            <template v-if="viewData.attachment_id">
+            <template v-if="getEffectiveAttachment(viewData)">
               <el-link 
                 v-if="getViewAttachmentUrl(viewData)" 
                 :href="getViewAttachmentUrl(viewData)" 
                 target="_blank" 
                 type="primary"
               >
-                {{ viewData.attachment?.original_name || viewData.attachment?.name || '查看' }}
+                {{ getAttachmentName(viewData) }}
               </el-link>
               <span v-else style="color: #909399;">附件加载中...</span>
             </template>
@@ -1497,6 +1512,7 @@ const rules = {
 const userList = ref([])
 const departmentList = ref([])
 const attachmentFileList = ref([])
+const inferredAttachmentInfo = ref(null)
 
 // 导入相关状态
 const importDialogVisible = ref(false)
@@ -1570,6 +1586,7 @@ function handleUploadSuccess(response) {
       uid: fileData.id,
       id: fileData.id
     }]
+    inferredAttachmentInfo.value = null
     ElMessage.success('上传成功')
   } else {
     ElMessage.error('上传失败：' + (response.msg || '未知错误'))
@@ -2195,18 +2212,7 @@ async function loadViewDetail(id) {
 }
 
 function getViewAttachmentUrl(row) {
-  if (!row || !row.attachment_id) return null
-  
-  if (row.attachment && row.attachment.url) {
-    return row.attachment.url
-  }
-  
-  if (row.attachment && row.attachment.folder && row.attachment.name) {
-    const baseUrl = config.baseURL || ''
-    return `${baseUrl}/${row.attachment.folder}/${row.attachment.name}`
-  }
-  
-  return null
+  return getAttachmentUrl(row)
 }
 
 function openForm(row) {
@@ -2217,6 +2223,7 @@ function openForm(row) {
   Object.assign(form, getEmptyForm())
   payPlanDeleteIds.value = []
   attachmentFileList.value = []
+  inferredAttachmentInfo.value = null
   loadDetail(row.id)
 }
 
@@ -2304,8 +2311,15 @@ async function loadDetail(id) {
           uid: data.attachment.id,
           id: data.attachment.id
         }]
+        inferredAttachmentInfo.value = null
       } else {
         attachmentFileList.value = []
+        inferredAttachmentInfo.value = data.oa_inferred_attachment
+          ? {
+              attachment: data.oa_inferred_attachment,
+              meta: data.oa_inferred_attachment_meta || {}
+            }
+          : null
       }
       
       Object.assign(form, data, { pay_plans: data.pay_plans || [] })
@@ -2541,23 +2555,31 @@ function getDepartmentName(departmentId) {
 }
 
 // 获取附件URL
-function getAttachmentUrl(row) {
-  if (!row.attachment_id) return null
-  
-  // 如果有attachment对象且有url属性，直接使用
-  if (row.attachment && row.attachment.url) {
-    return row.attachment.url
-  }
-  
-  // 如果有attachment对象但没有url，尝试构建URL
-  if (row.attachment && row.attachment.folder && row.attachment.name) {
-    const baseUrl = import.meta.env.VITE_APP_BASE_API?.replace('/api', '') || window.location.origin
-    return `${baseUrl}/${row.attachment.folder}/${row.attachment.name}`
+function getEffectiveAttachment(row) {
+  if (!row) return null
+  return row.effective_attachment || row.attachment || null
+}
+
+function getAttachmentName(row) {
+  const attachment = getEffectiveAttachment(row)
+  return attachment?.original_name || attachment?.name || '查看'
+}
+
+function buildAttachmentUrl(attachment) {
+  if (!attachment) return null
+  if (attachment.url) return attachment.url
+  if (attachment.folder && attachment.name) {
+    const apiBase = config.api?.baseURL || import.meta.env.VITE_APP_BASE_API || ''
+    const baseUrl = apiBase ? apiBase.replace(/\/api\/?$/, '') : window.location.origin
+    return `${baseUrl}/${attachment.folder}/${attachment.name}`
   }
-  
   return null
 }
 
+function getAttachmentUrl(row) {
+  return buildAttachmentUrl(getEffectiveAttachment(row))
+}
+
 async function loadUserList() {
   try {
     const response = await request.get('/backend/simple-user', { rows: 1000 })
@@ -3988,6 +4010,26 @@ onMounted(() => {
   font-size: 12px;
 }
 
+.oa-inferred-attachment {
+  margin-top: 8px;
+  padding: 8px 10px;
+  border: 1px solid #dcdfe6;
+  border-radius: 4px;
+  background: #fafafa;
+  color: #606266;
+  font-size: 12px;
+  line-height: 1.6;
+}
+
+.oa-inferred-attachment__title {
+  color: #909399;
+}
+
+.oa-inferred-attachment__meta {
+  margin-left: 12px;
+  color: #909399;
+}
+
 :deep(.error-row) {
   background-color: #fef0f0;
 }
diff --git a/src/views/payment/ContractSettings.vue b/src/views/payment/ContractSettings.vue
index 74fb1f5..cca2b17 100644
--- a/src/views/payment/ContractSettings.vue
+++ b/src/views/payment/ContractSettings.vue
@@ -49,6 +49,19 @@
                   :value="f.name"
                 />
               </el-select>
+              <el-checkbox
+                :model-value="item.value_transform === 'json_field'"
+                @change="(checked) => toggleJsonFieldTransform(item, checked)"
+              >
+                JSON取字段
+              </el-checkbox>
+              <el-input
+                v-if="item.value_transform === 'json_field'"
+                v-model="item.json_field"
+                placeholder="id"
+                class="w-120"
+              />
+              <el-tag v-if="isJsonCandidate(item, oaFieldsMain)" size="small" type="warning" effect="plain">疑似JSON</el-tag>
               <el-button type="danger" link @click="removeContractField(idx)">移除</el-button>
             </div>
             <el-button type="primary" link @click="addContractField">新增映射</el-button>
@@ -80,6 +93,19 @@
                   :value="f.name"
                 />
               </el-select>
+              <el-checkbox
+                :model-value="item.value_transform === 'json_field'"
+                @change="(checked) => toggleJsonFieldTransform(item, checked)"
+              >
+                JSON取字段
+              </el-checkbox>
+              <el-input
+                v-if="item.value_transform === 'json_field'"
+                v-model="item.json_field"
+                placeholder="id"
+                class="w-120"
+              />
+              <el-tag v-if="isJsonCandidate(item, oaFieldsSub)" size="small" type="warning" effect="plain">疑似JSON</el-tag>
               <el-button type="danger" link @click="removePayplanField(idx)">移除</el-button>
             </div>
             <el-button type="primary" link @click="addPayplanField">新增映射</el-button>
@@ -89,16 +115,175 @@
         <el-form-item>
           <el-button type="primary" :loading="saving" @click="handleSave">保存</el-button>
           <el-button @click="loadData">重置</el-button>
+          <el-button type="warning" @click="openSimulationDialog">模拟</el-button>
         </el-form-item>
       </el-form>
     </el-card>
+
+    <el-dialog
+      v-model="simulationDialogVisible"
+      title="合同映射模拟"
+      width="82%"
+      :close-on-click-modal="false"
+    >
+      <el-alert
+        title="模拟只读取当前页面设置和所选OA流程生成合同草稿，不会创建合同，不会写入付款计划。"
+        type="info"
+        show-icon
+        :closable="false"
+        class="mb-16"
+      />
+
+      <el-form label-width="160px">
+        <el-form-item label="合同流程">
+          <div class="simulation-flow-picker">
+            <el-select
+              v-model="simulationFlowId"
+              placeholder="选择一个合同流程"
+              filterable
+              remote
+              clearable
+              reserve-keyword
+              :remote-method="searchSimulationFlows"
+              :loading="simulationFlowsLoading"
+              class="simulation-flow-select"
+              @focus="loadSimulationFlows()"
+            >
+              <el-option
+                v-for="flow in simulationFlows"
+                :key="flow.id"
+                :label="flow.label"
+                :value="flow.id"
+              >
+                <div class="flow-option">
+                  <span>{{ flow.label }}</span>
+                  <small>{{ flow.created_at || '' }}</small>
+                </div>
+              </el-option>
+            </el-select>
+            <el-button type="primary" :loading="simulationLoading" :disabled="!simulationFlowId" @click="runSimulation">
+              生成模拟
+            </el-button>
+          </div>
+        </el-form-item>
+      </el-form>
+
+      <template v-if="simulationResult">
+        <el-divider content-position="left">合同签订表单预览</el-divider>
+        <el-form :model="simulationContract" label-width="150px" disabled class="simulation-contract-form">
+          <el-row :gutter="20">
+            <el-col :span="12">
+              <el-form-item label="合同编号">
+                <el-input :model-value="simulationContract.contract_no || ''" />
+              </el-form-item>
+            </el-col>
+            <el-col :span="12">
+              <el-form-item label="合同名称">
+                <el-input :model-value="simulationContract.title || ''" />
+              </el-form-item>
+            </el-col>
+          </el-row>
+          <el-form-item label="合同主要内容">
+            <el-input :model-value="simulationContract.main_content || ''" type="textarea" :rows="3" />
+          </el-form-item>
+          <el-row :gutter="20">
+            <el-col :span="12">
+              <el-form-item label="甲方">
+                <el-input :model-value="simulationContract.party_a || ''" />
+              </el-form-item>
+            </el-col>
+            <el-col :span="12">
+              <el-form-item label="乙方">
+                <el-input :model-value="simulationContract.party_b || ''" />
+              </el-form-item>
+            </el-col>
+          </el-row>
+          <el-row :gutter="20">
+            <el-col :span="12">
+              <el-form-item label="合同金额（元）">
+                <el-input :model-value="formatAmount(simulationContract.amount_total)" />
+              </el-form-item>
+            </el-col>
+            <el-col :span="12">
+              <el-form-item label="项目预算金额（元）">
+                <el-input :model-value="formatAmount(simulationContract.budget_amount)" />
+              </el-form-item>
+            </el-col>
+          </el-row>
+          <el-row :gutter="20">
+            <el-col :span="12">
+              <el-form-item label="金额类型">
+                <el-input :model-value="getAmountTypeLabel(simulationContract.amount_type)" />
+              </el-form-item>
+            </el-col>
+            <el-col :span="12">
+              <el-form-item label="合同类型">
+                <el-input :model-value="simulationContract.contract_type || simulationContract.contract_type_id || ''" />
+              </el-form-item>
+            </el-col>
+          </el-row>
+          <el-row :gutter="20">
+            <el-col :span="12">
+              <el-form-item label="签订日期">
+                <el-input :model-value="simulationContract.sign_date || ''" />
+              </el-form-item>
+            </el-col>
+            <el-col :span="12">
+              <el-form-item label="申请日期">
+                <el-input :model-value="simulationContract.apply_date || ''" />
+              </el-form-item>
+            </el-col>
+          </el-row>
+          <el-row :gutter="20">
+            <el-col :span="12">
+              <el-form-item label="合同履行期">
+                <el-input :model-value="simulationContract.perform_period || ''" />
+              </el-form-item>
+            </el-col>
+            <el-col :span="12">
+              <el-form-item label="付款方式">
+                <el-input :model-value="simulationContract.pay_method || ''" />
+              </el-form-item>
+            </el-col>
+          </el-row>
+          <el-form-item label="合同盖章版本附件">
+            <el-input :model-value="formatAttachmentValue(simulationContract.attachment_id)" />
+          </el-form-item>
+          <el-form-item label="备注">
+            <el-input :model-value="simulationContract.remark || ''" type="textarea" :rows="2" />
+          </el-form-item>
+        </el-form>
+
+        <el-divider content-position="left">付款计划预览</el-divider>
+        <el-table :data="simulationPayPlans" border size="small" class="mb-16">
+          <el-table-column prop="phase_no" label="期次" width="100" />
+          <el-table-column prop="due_date" label="计划付款日" width="150" />
+          <el-table-column prop="amount_plan" label="计划金额" width="160">
+            <template #default="{ row }">
+              {{ formatAmount(row.amount_plan) }}
+            </template>
+          </el-table-column>
+        </el-table>
+
+        <el-divider content-position="left">映射结果明细</el-divider>
+        <el-table :data="simulationMappingRows" border size="small">
+          <el-table-column prop="targetLabel" label="合同字段" width="180" />
+          <el-table-column prop="sourceLabel" label="OA字段" width="180" />
+          <el-table-column prop="value" label="模拟值" show-overflow-tooltip />
+        </el-table>
+      </template>
+
+      <template #footer>
+        <el-button @click="simulationDialogVisible = false">关闭</el-button>
+      </template>
+    </el-dialog>
   </div>
 </template>
 
 <script setup>
 import { ref, watch } from 'vue'
 import { ElMessage } from 'element-plus'
-import { contractSettingsAPI } from '@/utils/api'
+import { contractAPI, contractSettingsAPI } from '@/utils/api'
 import { Setting } from '@element-plus/icons-vue'
 
 const form = ref(getEmptyForm())
@@ -110,6 +295,30 @@ const oaFieldsSub = ref([])
 const oaFieldsLoading = ref(false)
 const contractFields = ref([])
 const payplanFields = ref([])
+const simulationDialogVisible = ref(false)
+const simulationFlows = ref([])
+const simulationFlowsLoading = ref(false)
+const simulationFlowId = ref('')
+const simulationLoading = ref(false)
+const simulationResult = ref(null)
+const simulationContract = ref({})
+const simulationPayPlans = ref([])
+const simulationMappingRows = ref([])
+
+function normalizeNullableId(value) {
+  if (value === null || value === undefined || value === '') {
+    return ''
+  }
+  const id = Number(value)
+  return Number.isNaN(id) ? value : id
+}
+
+function normalizeModelOptions(list) {
+  return (Array.isArray(list) ? list : []).map((item) => ({
+    ...item,
+    id: normalizeNullableId(item.id)
+  }))
+}
 
 function getEmptyForm() {
   return {
@@ -154,14 +363,142 @@ function removePayplanField(idx) {
   form.value.payplan_field_mapping.splice(idx, 1)
 }
 
+function toggleJsonFieldTransform(item, checked) {
+  if (checked) {
+    item.value_transform = 'json_field'
+    if (!item.json_field) {
+      item.json_field = 'id'
+    }
+    return
+  }
+  item.value_transform = ''
+  item.json_field = ''
+}
+
+function getSelectedOaField(item, fields) {
+  return fields.find((field) => field.name === item.oa_field)
+}
+
+function isJsonCandidate(item, fields) {
+  const field = getSelectedOaField(item, fields)
+  return ['file', 'image', 'upload', 'relation'].includes(field?.type)
+}
+
+function formatAmount(amount) {
+  if (amount === null || amount === undefined || amount === '') {
+    return ''
+  }
+  const num = Number(amount)
+  if (Number.isNaN(num)) {
+    return String(amount)
+  }
+  return num.toLocaleString('zh-CN', {
+    minimumFractionDigits: 2,
+    maximumFractionDigits: 2
+  })
+}
+
+function getAmountTypeLabel(value) {
+  if (value === 'fixed') return '闭口合同（金额确定）'
+  if (value === 'open') return '框架协议/开口合同（金额不确定）'
+  return value || ''
+}
+
+function formatAttachmentValue(value) {
+  if (value === null || value === undefined || value === '') {
+    return ''
+  }
+  if (Array.isArray(value)) {
+    return value.join(', ')
+  }
+  if (typeof value === 'object') {
+    return value.name || value.original_name || value.id || JSON.stringify(value)
+  }
+  return `附件ID：${value}`
+}
+
+function getFieldLabel(fields, fieldName) {
+  const field = fields.find((item) => item.field === fieldName || item.name === fieldName)
+  return field?.label || fieldName || ''
+}
+
+function buildSimulationMappingRows(contract) {
+  return (Array.isArray(form.value.contract_field_mapping) ? form.value.contract_field_mapping : [])
+    .filter((item) => item.budget_field || item.oa_field)
+    .map((item) => ({
+      targetLabel: getFieldLabel(contractFields.value, item.budget_field),
+      sourceLabel: getFieldLabel(oaFieldsMain.value, item.oa_field),
+      value: contract?.[item.budget_field] ?? ''
+    }))
+}
+
+async function loadSimulationFlows(keyword = '') {
+  if (!form.value.oa_custom_model_id) {
+    simulationFlows.value = []
+    return
+  }
+  simulationFlowsLoading.value = true
+  try {
+    const res = await contractSettingsAPI.getOaFlows({
+      custom_model_id: form.value.oa_custom_model_id,
+      keyword,
+      limit: 30
+    })
+    simulationFlows.value = res?.data || res || []
+  } catch (e) {
+    simulationFlows.value = []
+  } finally {
+    simulationFlowsLoading.value = false
+  }
+}
+
+function searchSimulationFlows(keyword) {
+  loadSimulationFlows(keyword)
+}
+
+async function openSimulationDialog() {
+  if (!form.value.oa_custom_model_id) {
+    ElMessage.warning('请先选择主表对应OA模型')
+    return
+  }
+  simulationDialogVisible.value = true
+  simulationResult.value = null
+  simulationContract.value = {}
+  simulationPayPlans.value = []
+  simulationMappingRows.value = []
+  await loadSimulationFlows()
+}
+
+async function runSimulation() {
+  if (!simulationFlowId.value) {
+    ElMessage.warning('请选择合同流程')
+    return
+  }
+  simulationLoading.value = true
+  try {
+    const res = await contractAPI.simulateFromFlow(simulationFlowId.value, form.value)
+    const data = res?.data || res || {}
+    const prepared = data.prepared_contract || {}
+    simulationResult.value = prepared
+    simulationContract.value = prepared.contract || {}
+    simulationPayPlans.value = Array.isArray(prepared.pay_plans) ? prepared.pay_plans : []
+    simulationMappingRows.value = buildSimulationMappingRows(simulationContract.value)
+    ElMessage.success('模拟生成完成，未写入任何合同数据')
+  } catch (e) {
+    ElMessage.error(e?.message || '模拟失败')
+  } finally {
+    simulationLoading.value = false
+  }
+}
+
 async function loadData() {
   try {
     const res = await contractSettingsAPI.get()
     const data = res?.data || res
     if (data) {
       form.value = {
-        oa_custom_model_id: data.oa_custom_model_id || '',
-        oa_custom_model_id_for_payplan: data.oa_custom_model_id_for_payplan || '',
+        oa_custom_model_id: normalizeNullableId(data.oa_custom_model_id),
+        oa_custom_model_id_for_payplan: normalizeNullableId(data.oa_custom_model_id_for_payplan),
         contract_field_mapping: data.contract_field_mapping?.length ? data.contract_field_mapping : getEmptyForm().contract_field_mapping,
         payplan_field_mapping: data.payplan_field_mapping?.length ? data.payplan_field_mapping : getEmptyForm().payplan_field_mapping
       }
@@ -176,13 +513,13 @@ async function loadData() {
 async function loadOptions() {
   try {
     const modelsRes = await contractSettingsAPI.getOaModels()
-    oaModels.value = modelsRes?.data || modelsRes || []
+    oaModels.value = normalizeModelOptions(modelsRes?.data || modelsRes || [])
   } catch (e) {
     oaModels.value = []
   }
   try {
     const subRes = await contractSettingsAPI.getOaSubModels()
-    oaSubModels.value = subRes?.data || subRes || []
+    oaSubModels.value = normalizeModelOptions(subRes?.data || subRes || [])
   } catch (e) {
     oaSubModels.value = []
   }
@@ -285,5 +622,29 @@ watch(() => [form.value.oa_custom_model_id, form.value.oa_custom_model_id_for_pa
 .w-200 {
   width: 200px;
 }
+.w-120 {
+  width: 120px;
+}
+.mb-16 {
+  margin-bottom: 16px;
+}
+.simulation-flow-picker {
+  display: flex;
+  align-items: center;
+  gap: 12px;
+}
+.simulation-flow-select {
+  width: 520px;
+}
+.flow-option {
+  display: flex;
+  justify-content: space-between;
+  gap: 16px;
+}
+.flow-option small {
+  color: #909399;
+}
+.simulation-contract-form {
+  max-width: 1000px;
+}
 </style>
-
diff --git a/src/views/payment/IndirectPayment.vue b/src/views/payment/IndirectPayment.vue
index b43b3ea..c544f38 100644
--- a/src/views/payment/IndirectPayment.vue
+++ b/src/views/payment/IndirectPayment.vue
@@ -2413,6 +2413,10 @@ const handleRelationCheckboxChange = (flowId, fieldName, rowId, checked) => {
     relationCheckboxStates.value[key] = {}
   }
   relationCheckboxStates.value[key][rowId] = checked
+
+  if (!checked && relationSelectedRows.value[key]?.[rowId]) {
+    relationSelectedRows.value[key][rowId].quantity = 0
+  }
 }
 
 // 检查relation行的checkbox是否被选中（独立状态）