fix: correct targeted search logic for material/stock list to prevent unrelated results

inventory-backend/test_barcode_limit.py

@@ -0,0 +1,139 @@
+import socket
+import os
+from io import BytesIO
+from PIL import Image, ImageDraw
+
+# 引入条形码生成库
+try:
+    import barcode
+    from barcode.writer import ImageWriter
+except ImportError:
+    print("❌ 错误: 请先安装 python-barcode (pip install python-barcode)")
+    exit()
+
+
+class BarcodeStackTester:
+    # 打印机配置
+    PRINTER_IP = "192.168.9.205"
+    PRINTER_PORT = 9100
+
+    # 纸张配置: 40mm x 30mm @ 300 DPI
+    DOTS_PER_MM = 12
+    CANVAS_W = int(40 * DOTS_PER_MM)  # 480px
+    CANVAS_H = int(30 * DOTS_PER_MM)  # 360px
+
+    @staticmethod
+    def _generate_raw_barcode(content, bar_height_mm=4):
+        """
+        生成原始条码图片 (不强制缩放宽度，让其自然生长)
+        """
+        try:
+            # Code128 自动优化 (数字会被压缩，所以20位数字其实不长)
+            writer = ImageWriter()
+
+            # module_width: 条码黑条的最小宽度(mm)。
+            # 0.2mm 在 300DPI 下约等于 2.4像素。这是一个比较清晰且节省空间的数值。
+            # 如果设得太大(如0.3)，20位可能会超出40mm纸张。
+            options = {
+                "module_width": 0.2,
+                "module_height": bar_height_mm,  # 条码高度
+                "quiet_zone": 2.0,  # 两侧留白(mm)
+                "write_text": False,  # 【关键】不写文字
+                "dpi": 300  # 对应打印机DPI
+            }
+
+            code_img = barcode.get('code128', content, writer=writer)
+
+            # 渲染到内存
+            buffer = BytesIO()
+            code_img.write(buffer, options=options)
+            buffer.seek(0)
+
+            return Image.open(buffer)
+        except Exception as e:
+            print(f"生成失败: {e}")
+            return None
+
+    def run_test(self):
+        # 1. 创建白色底图 (40x30mm)
+        canvas = Image.new('RGB', (self.CANVAS_W, self.CANVAS_H), color='white')
+
+        # 测试用例: 长度从小到大
+        test_lengths = [13, 15, 17, 20]
+
+        # 布局参数
+        current_y = 20  # 顶部起始留白 (px)
+        gap = 10  # 间距 (px)
+
+        print("-" * 50)
+        print("🚀 开始生成堆叠条码测试图...")
+
+        for length in test_lengths:
+            # 生成全7的内容
+            content = "7" * length
+            print(f"  正在处理: {length}位 -> {content}")
+
+            # 生成条码 (高度设为5mm左右，方便在一张纸上放下4个)
+            bar_img = self._generate_raw_barcode(content, bar_height_mm=5)
+
+            if bar_img:
+                # 计算居中位置
+                # bar_img.width 是条码生成的自然宽度
+                x_pos = (self.CANVAS_W - bar_img.width) // 2
+
+                # 如果宽度超出了纸张 (x_pos < 0)，说明40mm纸打不下这么多位
+                if x_pos < 0:
+                    print(f"    ⚠️ 警告: {length}位条码过宽 ({bar_img.width}px > {self.CANVAS_W}px)，可能会被裁切！")
+                    x_pos = 0
+
+                    # 粘贴到画布
+                canvas.paste(bar_img, (x_pos, current_y))
+
+                # 更新Y坐标，准备画下一个
+                current_y += bar_img.height + gap
+            else:
+                print("    生成失败")
+
+        # 2. 保存预览图
+        preview_file = "test_stack_preview.jpg"
+        canvas.save(preview_file)
+        print(f"✅ 图片已生成: {preview_file} (请打开查看宽度是否超出)")
+
+        # 3. 发送打印 (二值化处理)
+        self._send_to_printer(canvas)
+
+    def _send_to_printer(self, img_rgb):
+        try:
+            # 转二值化 (白=1, 黑=0)
+            img_bw = img_rgb.convert('L').convert('1', dither=Image.Dither.NONE)
+            bitmap_data = img_bw.tobytes()
+
+            width_bytes = (img_bw.width + 7) // 8
+            height_dots = img_bw.height
+
+            # TSPL 指令
+            header = (
+                f"SIZE 40 mm, 30 mm\r\n"
+                "GAP 2 mm, 0 mm\r\n"
+                "CLS\r\n"
+                "DIRECTION 1\r\n"
+            ).encode('gbk')
+
+            bitmap_cmd = f"BITMAP 0,0,{width_bytes},{height_dots},0,".encode('gbk')
+            footer = b"\r\nPRINT 1,1\r\n"
+
+            print("🖨️ 正在发送打印指令...")
+            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+            s.settimeout(5)
+            s.connect((self.PRINTER_IP, self.PRINTER_PORT))
+            s.sendall(header + bitmap_cmd + bitmap_data + footer)
+            s.close()
+            print("✅ 指令已发送")
+
+        except Exception as e:
+            print(f"❌ 打印失败: {e}")
+
+
+if __name__ == "__main__":
+    tester = BarcodeStackTester()
+    tester.run_test()