1

flutter_app/lib/camera/model_catalog_section.dart

@@ -2,9 +2,15 @@ import 'package:flutter/material.dart';
 
 import '../models/model_manager.dart';
 
-/// 设置弹层「模型清单」区块：2 列封面缩略图网格。
-/// 未下载 →「使用」点击后显示下载进度，完成自动激活；已下载未激活 → 直接激活；
-/// 已激活 → 再次点击取消；下载失败 → 失败提示 + 重试。
+/// 设置弹层「模型清单」区块：顶部「识别模式」分段控件（s 高识别 / n 高性能，
+/// 默认 s，持久化本地；切换即热加载该档位已激活模型），下方 2 列封面缩略图网格。
+/// 双档位：每数据集至多两张卡片（s/n 各一），卡片带档位角标；
+/// 卡片状态（下载进度/激活）按 (数据集, 档位) 独立记账。
+///
+/// 卡片状态机（档位 == 当前识别档位时与原单档行为一致）：
+/// - 未下载 →「使用/下载」：下载完成自动激活（当前档立即使用，非当前档备好待切）；
+/// - 已下载未激活 →「使用」直接激活；已激活且当前档 →「已使用」点击取消；
+/// - 已激活但属非当前档 →「已备好」（已下载就绪，点击切换到该档立即生效）。
 class ModelCatalogSection extends StatelessWidget {
   final ModelManager manager;
 
@@ -15,11 +21,29 @@ class ModelCatalogSection extends StatelessWidget {
     return ListenableBuilder(
       listenable: manager,
       builder: (context, _) {
-        final items = manager.catalog;
+        // 目录行按 (数据集, 档位) 稳定排序：同数据集 s 前 n 后相邻展示
+        final items = [...manager.catalog]..sort((a, b) {
+            if (a.datasetId != b.datasetId) {
+              return a.datasetId.compareTo(b.datasetId);
+            }
+            return a.variant.compareTo(b.variant);
+          });
         return Column(
           crossAxisAlignment: CrossAxisAlignment.start,
           mainAxisSize: MainAxisSize.min,
           children: [
+            Row(
+              children: [
+                const Text('识别模式',
+                    style: TextStyle(color: Colors.white70, fontSize: 14)),
+                const Spacer(),
+                _ModeToggle(manager: manager),
+              ],
+            ),
+            const SizedBox(height: 2),
+            const Text('切换即加载该档位已激活模型（激活状态跨档保留）',
+                style: TextStyle(color: Colors.white38, fontSize: 11)),
+            const SizedBox(height: 12),
             Row(
               children: [
                 const Text('模型清单',
@@ -71,6 +95,57 @@ class ModelCatalogSection extends StatelessWidget {
   }
 }
 
+/// 档位分段控件：s 高识别 / n 高性能
+class _ModeToggle extends StatelessWidget {
+  final ModelManager manager;
+
+  const _ModeToggle({required this.manager});
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      padding: const EdgeInsets.all(2),
+      decoration: BoxDecoration(
+        color: Colors.white12,
+        borderRadius: BorderRadius.circular(8),
+      ),
+      child: Row(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          for (final v in const [kVariantS, kVariantN]) ...[
+            if (v != kVariantS) const SizedBox(width: 2),
+            _seg(v),
+          ],
+        ],
+      ),
+    );
+  }
+
+  Widget _seg(String v) {
+    final selected = manager.mode == v;
+    final label = v == kVariantS ? 's 高识别' : 'n 高性能';
+    return InkWell(
+      borderRadius: BorderRadius.circular(6),
+      onTap: () => manager.setMode(v),
+      child: Container(
+        padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 4),
+        decoration: BoxDecoration(
+          color: selected ? Colors.greenAccent : Colors.transparent,
+          borderRadius: BorderRadius.circular(6),
+        ),
+        child: Text(
+          label,
+          style: TextStyle(
+            color: selected ? Colors.black : Colors.white70,
+            fontSize: 12,
+            fontWeight: selected ? FontWeight.bold : FontWeight.normal,
+          ),
+        ),
+      ),
+    );
+  }
+}
+
 class _ModelCard extends StatelessWidget {
   final ModelCatalogItem item;
   final ModelManager manager;
@@ -79,33 +154,62 @@ class _ModelCard extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    final active = manager.isActive(item.datasetId);
-    final downloaded = manager.isDownloaded(item.datasetId);
-    final progress = manager.progressOf(item.datasetId);
-    final error = manager.errorOf(item.datasetId);
+    final variant = item.variant;
+    final sameMode = manager.mode == variant;
+    final active = manager.isActive(item.datasetId, variant);
+    final downloaded = manager.isDownloaded(item.datasetId, variant);
+    final progress = manager.progressOf(item.datasetId, variant);
+    final error = manager.errorOf(item.datasetId, variant);
+    final accent =
+        variant == kVariantS ? Colors.greenAccent : Colors.orangeAccent;
 
     final thumb = ClipRRect(
       borderRadius: BorderRadius.circular(8),
       child: AspectRatio(
         aspectRatio: 4 / 3,
-        child: Image.network(
-          '${manager.baseUrl}${item.coverUrl}',
-          fit: BoxFit.cover,
-          loadingBuilder: (context, child, chunk) => chunk == null
-              ? child
-              : Container(
-                  color: Colors.white12,
-                  child: const Center(
-                      child: SizedBox(
-                          width: 20,
-                          height: 20,
-                          child: CircularProgressIndicator(
-                              strokeWidth: 2)))),
-          errorBuilder: (context, error, stack) => Container(
-            color: Colors.white12,
-            child: const Icon(Icons.image_not_supported_outlined,
-                color: Colors.white38),
-          ),
+        child: Stack(
+          fit: StackFit.expand,
+          children: [
+            Image.network(
+              '${manager.baseUrl}${item.coverUrl}',
+              fit: BoxFit.cover,
+              loadingBuilder: (context, child, chunk) => chunk == null
+                  ? child
+                  : Container(
+                      color: Colors.white12,
+                      child: const Center(
+                          child: SizedBox(
+                              width: 20,
+                              height: 20,
+                              child: CircularProgressIndicator(
+                                  strokeWidth: 2)))),
+              errorBuilder: (context, error, stack) => Container(
+                color: Colors.white12,
+                child: const Icon(Icons.image_not_supported_outlined,
+                    color: Colors.white38),
+              ),
+            ),
+            // 档位角标：s 高识别（绿）/ n 高性能（橙）
+            Positioned(
+              top: 4,
+              left: 4,
+              child: Container(
+                padding:
+                    const EdgeInsets.symmetric(horizontal: 5, vertical: 1),
+                decoration: BoxDecoration(
+                  color: accent,
+                  borderRadius: BorderRadius.circular(4),
+                ),
+                child: Text(
+                  variant == kVariantS ? 's' : 'n',
+                  style: const TextStyle(
+                      color: Colors.black87,
+                      fontSize: 10,
+                      fontWeight: FontWeight.bold),
+                ),
+              ),
+            ),
+          ],
         ),
       ),
     );
@@ -132,7 +236,8 @@ class _ModelCard extends StatelessWidget {
                 ),
               ),
               TextButton(
-                onPressed: () => manager.cancelDownload(item.datasetId),
+                onPressed: () =>
+                    manager.cancelDownload(item.datasetId, variant),
                 style: TextButton.styleFrom(
                   foregroundColor: Colors.white54,
                   visualDensity: VisualDensity.compact,
@@ -160,22 +265,38 @@ class _ModelCard extends StatelessWidget {
           ),
         ],
       );
-    } else if (active) {
-      action = SizedBox(
-        height: 30,
-        child: OutlinedButton(
-          onPressed: () => manager.setActive(item.datasetId, false),
-          style: OutlinedButton.styleFrom(
-              foregroundColor: Colors.greenAccent,
-              side: const BorderSide(color: Colors.greenAccent)),
-          child: const Text('已使用', style: TextStyle(fontSize: 12)),
-        ),
-      );
+    } else if (active && downloaded) {
+      if (sameMode) {
+        // 当前档已激活：点击取消
+        action = SizedBox(
+          height: 30,
+          child: OutlinedButton(
+            onPressed: () =>
+                manager.setActive(item.datasetId, variant, false),
+            style: OutlinedButton.styleFrom(
+                foregroundColor: Colors.greenAccent,
+                side: const BorderSide(color: Colors.greenAccent)),
+            child: const Text('已使用', style: TextStyle(fontSize: 12)),
+          ),
+        );
+      } else {
+        // 非当前档已备好（激活保留）：点击切换到该档立即生效
+        action = SizedBox(
+          height: 30,
+          child: OutlinedButton(
+            onPressed: () => manager.setMode(variant),
+            style: OutlinedButton.styleFrom(
+                foregroundColor: Colors.amberAccent,
+                side: const BorderSide(color: Colors.amberAccent)),
+            child: const Text('已备好', style: TextStyle(fontSize: 12)),
+          ),
+        );
+      }
     } else if (downloaded) {
       action = SizedBox(
         height: 30,
         child: FilledButton(
-          onPressed: () => manager.setActive(item.datasetId, true),
+          onPressed: () => manager.setActive(item.datasetId, variant, true),
           style: FilledButton.styleFrom(
               backgroundColor: Colors.greenAccent,
               foregroundColor: Colors.black,
@@ -192,7 +313,7 @@ class _ModelCard extends StatelessWidget {
               backgroundColor: Colors.greenAccent,
               foregroundColor: Colors.black,
               visualDensity: VisualDensity.compact),
-          child: const Text('使用', style: TextStyle(fontSize: 12)),
+          child: Text(sameMode ? '使用' : '下载', style: const TextStyle(fontSize: 12)),
         ),
       );
     }
@@ -208,11 +329,31 @@ class _ModelCard extends StatelessWidget {
         children: [
           Expanded(child: Center(child: thumb)),
           const SizedBox(height: 6),
-          Text(item.datasetName,
-              maxLines: 1,
-              overflow: TextOverflow.ellipsis,
-              style: const TextStyle(
-                  color: Colors.white, fontSize: 13, fontWeight: FontWeight.w600)),
+          Row(
+            children: [
+              Expanded(
+                child: Text(item.datasetName,
+                    maxLines: 1,
+                    overflow: TextOverflow.ellipsis,
+                    style: const TextStyle(
+                        color: Colors.white,
+                        fontSize: 13,
+                        fontWeight: FontWeight.w600)),
+              ),
+              Container(
+                padding:
+                    const EdgeInsets.symmetric(horizontal: 4, vertical: 1),
+                decoration: BoxDecoration(
+                  color: accent.withValues(alpha: 0.25),
+                  borderRadius: BorderRadius.circular(4),
+                ),
+                child: Text(
+                  variant == kVariantS ? '高识别' : '高性能',
+                  style: TextStyle(color: accent, fontSize: 9),
+                ),
+              ),
+            ],
+          ),
           const SizedBox(height: 2),
           Text('v${item.version}',
               style: const TextStyle(color: Colors.white38, fontSize: 10)),