feat(pdf): 添加PDF文件列表功能并优化报告页面

- 新增PDF文件列表页面，显示服务器上所有历史PDF报告
- 在报告页面添加"更早的"按钮链接到PDF列表
- 将历史PDF链接显示从30天改为7天
- 优化PDF生成错误处理和日志记录
- 更新按钮文字描述为"预览PDF模板"

core/views.py

@@ -435,12 +435,27 @@ def generate_report(request):
     # 获取家庭事项统计
     family_task_stats = FamilyTask.objects.values('type').annotate(count=Count('id'))
     
-    # 获取过去30天的日期列表，用于生成历史PDF链接
+    # 获取最近7天的日期列表，用于生成历史PDF链接
     historical_dates = []
-    for i in range(1, 31):
+    for i in range(1, 8):
         historical_date = today - timedelta(days=i)
         historical_dates.append(historical_date)
     
+    # 检查是否有更早的PDF文件
+    has_earlier_pdfs = False
+    seven_days_ago = today - timedelta(days=7)
+    pdf_files = [f for f in os.listdir(settings.REPORTS_ROOT) if f.endswith('.pdf')]
+    for pdf_file in pdf_files:
+        try:
+            # 从文件名中提取日期
+            date_str = pdf_file.replace('report_', '').replace('.pdf', '')
+            file_date = datetime.strptime(date_str, '%Y-%m-%d').date()
+            if file_date < seven_days_ago:
+                has_earlier_pdfs = True
+                break
+        except Exception:
+            continue
+    
     context = {
         'today': today,
         'yesterday': yesterday,
@@ -449,6 +464,7 @@ def generate_report(request):
         'today_plan': today_plan,
         'family_task_stats': family_task_stats,
         'historical_dates': historical_dates,
+        'has_earlier_pdfs': has_earlier_pdfs,
     }
     
     return render(request, 'core/report.html', context)
@@ -487,47 +503,52 @@ def generate_pdf_report(request, date):
         return HttpResponse("PDF功能不可用，请检查WeasyPrint库是否正确安装", status=500)
     
     logger.info(f"用户生成PDF报告: {date}")
-    report_date = datetime.strptime(date, '%Y-%m-%d').date()
-    yesterday = report_date - timedelta(days=1)
     
-    # 获取指定日期的记录
-    yesterday_reading = ReadingRecord.objects.filter(date=yesterday)
-    yesterday_insight = InsightRecord.objects.filter(date=yesterday)
-    today_plan = TodayPlan.objects.filter(date=report_date)
-    
-    # 获取家庭事项统计
-    family_task_stats = FamilyTask.objects.values('type').annotate(count=Count('id'))
-    
-    context = {
-        'today': report_date,
-        'yesterday': yesterday,
-        'yesterday_reading': yesterday_reading,
-        'yesterday_insight': yesterday_insight,
-        'today_plan': today_plan,
-        'family_task_stats': family_task_stats,
-    }
-    
-    # 渲染HTML模板
-    html_string = render(request, 'core/report_pdf.html', context).content.decode('utf-8')
-    
-    # 生成PDF
-    pdf_file = f"report_{date}.pdf"
-    pdf_path = os.path.join(settings.REPORTS_ROOT, pdf_file)
-    
-    # 确保报告目录存在
-    os.makedirs(settings.REPORTS_ROOT, exist_ok=True)
-    
-    # 动态导入WeasyPrint
-    from weasyprint import HTML
-    HTML(string=html_string).write_pdf(pdf_path)
-    
-    logger.info(f"PDF报告生成成功: {pdf_path}")
-    
-    # 返回PDF文件
-    with open(pdf_path, 'rb') as f:
-        response = HttpResponse(f.read(), content_type='application/pdf')
-        response['Content-Disposition'] = f'attachment; filename="{pdf_file}"'
-        return response
+    try:
+        report_date = datetime.strptime(date, '%Y-%m-%d').date()
+        yesterday = report_date - timedelta(days=1)
+        
+        # 获取指定日期的记录
+        yesterday_reading = ReadingRecord.objects.filter(date=yesterday)
+        yesterday_insight = InsightRecord.objects.filter(date=yesterday)
+        today_plan = TodayPlan.objects.filter(date=report_date)
+        
+        # 获取家庭事项统计
+        family_task_stats = FamilyTask.objects.values('type').annotate(count=Count('id'))
+        
+        context = {
+            'today': report_date,
+            'yesterday': yesterday,
+            'yesterday_reading': yesterday_reading,
+            'yesterday_insight': yesterday_insight,
+            'today_plan': today_plan,
+            'family_task_stats': family_task_stats,
+        }
+        
+        # 渲染HTML模板
+        html_string = render(request, 'core/report_pdf.html', context).content.decode('utf-8')
+        
+        # 生成PDF
+        pdf_file = f"report_{date}.pdf"
+        pdf_path = os.path.join(settings.REPORTS_ROOT, pdf_file)
+        
+        # 确保报告目录存在
+        os.makedirs(settings.REPORTS_ROOT, exist_ok=True)
+        
+        # 动态导入WeasyPrint
+        from weasyprint import HTML
+        HTML(string=html_string).write_pdf(pdf_path)
+        
+        logger.info(f"PDF报告生成成功: {pdf_path}")
+        
+        # 返回PDF文件
+        with open(pdf_path, 'rb') as f:
+            response = HttpResponse(f.read(), content_type='application/pdf')
+            response['Content-Disposition'] = f'attachment; filename="{pdf_file}"'
+            return response
+    except Exception as e:
+        logger.error(f"生成PDF报告失败: {str(e)}")
+        return HttpResponse(f"生成PDF报告失败: {str(e)}", status=500)
 
 # 系统配置
 def system_settings(request):
@@ -625,3 +646,36 @@ def send_email_view(request):
 def send_email(request):
     """发送邮件别名"""
     return send_email_view(request)
+
+# PDF文件列表
+def pdf_list(request):
+    """显示服务器上已有的PDF文件列表"""
+    logger.info("用户访问PDF文件列表页面")
+    
+    # 获取所有PDF文件
+    pdf_files = [f for f in os.listdir(settings.REPORTS_ROOT) if f.endswith('.pdf')]
+    
+    # 解析文件名，提取日期，并按日期降序排序
+    pdf_info = []
+    for pdf_file in pdf_files:
+        try:
+            # 从文件名中提取日期
+            date_str = pdf_file.replace('report_', '').replace('.pdf', '')
+            file_date = datetime.strptime(date_str, '%Y-%m-%d').date()
+            pdf_info.append({
+                'filename': pdf_file,
+                'date': file_date,
+                'date_str': date_str
+            })
+        except Exception as e:
+            logger.error(f"解析PDF文件名失败: {pdf_file}, 错误: {str(e)}")
+            continue
+    
+    # 按日期降序排序
+    pdf_info.sort(key=lambda x: x['date'], reverse=True)
+    
+    context = {
+        'pdf_files': pdf_info
+    }
+    
+    return render(request, 'core/pdf_list.html', context)