feat: DesignPanel switches between front and back design

frontend/src/components/DesignPanel.vue

@@ -1,5 +1,68 @@
 <template>
   <div class="design-panel">
+    <!-- ===== 背面设计面板 ===== -->
+    <template v-if="isBack">
+      <section>
+        <h4>背面背景色</h4>
+        <div class="row">
+          <input type="color" :value="backDesign.background_color" @input="setBackBgColor($event.target.value)" />
+          <input type="text" :value="backDesign.background_color" @change="setBackBgColor($event.target.value)" />
+        </div>
+      </section>
+
+      <section>
+        <h4>背面边框</h4>
+        <div class="row">
+          <label class="mini-label">颜色</label>
+          <input type="color" :value="backDesign.border_color" @input="setBackDesign('border_color', $event.target.value)" />
+          <label class="mini-label">粗细</label>
+          <input type="number" min="0" max="40" :value="backDesign.border_width"
+                 @change="setBackDesign('border_width', parseInt($event.target.value) || 0)" />
+        </div>
+      </section>
+
+      <section>
+        <h4>图案色调</h4>
+        <p class="hint">为背面图案叠加一层半透明色调</p>
+        <div class="row">
+          <input type="color" :value="backDesign.pattern_color || '#C0A050'"
+                 @input="setBackDesign('pattern_color', $event.target.value)" />
+          <button v-if="backDesign.pattern_color" @click="setBackDesign('pattern_color', null)" class="mini ghost">清除色调</button>
+        </div>
+      </section>
+
+      <section>
+        <h4>背面图片</h4>
+        <div class="row">
+          <button @click="uploadBackImage" class="mini">上传背面图</button>
+        </div>
+        <input ref="backImageInput" type="file" accept="image/*" @change="onBackImageFile" hidden />
+        <div v-if="backDesign.image" class="row">
+          <img :src="backDesign.image" class="thumb" />
+          <button @click="setBackDesign('image', null)" class="mini ghost">清除</button>
+        </div>
+      </section>
+
+      <section v-if="backDesign.image">
+        <h4>图片位置微调</h4>
+        <p class="hint">拖动滑块微调素材图片的位置与缩放（0 = 默认）</p>
+        <div class="pip-row">
+          <label class="mini-label">dx</label>
+          <input type="range" min="-0.05" max="0.05" step="0.005"
+                 :value="backImageOffsetVal('image_dx')" @input="setBackImageOffset('image_dx', $event.target.value)" />
+          <label class="mini-label">dy</label>
+          <input type="range" min="-0.05" max="0.05" step="0.005"
+                 :value="backImageOffsetVal('image_dy')" @input="setBackImageOffset('image_dy', $event.target.value)" />
+          <label class="mini-label">缩放</label>
+          <input type="range" min="0.6" max="1.4" step="0.05"
+                 :value="backImageOffsetVal('image_scale')" @input="setBackImageOffset('image_scale', $event.target.value)" />
+        </div>
+        <button @click="resetBackImageOffset" class="mini ghost">重置图片位置</button>
+      </section>
+    </template>
+
+    <!-- ===== 正面设计面板 ===== -->
+    <template v-else>
       <!-- 背景色 -->
       <section>
         <h4>背景色</h4>
@@ -91,7 +154,7 @@
         </div>
       </section>
 
-    <!-- 图片位置微调（大小王 / 背面） -->
+      <!-- 图片位置微调（大小王） -->
       <section v-if="showImageOffset">
         <h4>图片位置微调</h4>
         <p class="hint">拖动滑块微调素材图片的位置与缩放（0 = 默认）</p>
@@ -132,6 +195,7 @@
         </div>
         <button @click="resetLayout" class="mini ghost">重置本点数布局</button>
       </section>
+    </template>
   </div>
 </template>
 
@@ -142,6 +206,9 @@ import { SUITS, SUIT_TEXT, LAYOUT_POSITIONS, isJoker } from '@/utils/cardLayout'
 
 const store = useProjectStore()
 const design = computed(() => store.effectiveDesign)
+const backDesign = computed(() => store.effectiveBackDesign)
+const isBack = computed(() => store.currentCard === 'back')
+
 const override = computed(() => {
   if (!store.project || !store.currentCard) return null
   return (store.project.card_overrides || {})[store.currentCard] || null
@@ -152,6 +219,7 @@ const suits = SUITS
 const suitSymbol = (s) => SUIT_TEXT[s]
 const suitLabel = (s) => ({ spade: '黑桃', heart: '红桃', club: '梅花', diamond: '方块' })[s]
 
+// ===== 正面相关 =====
 const bgFileInput = ref(null)
 function uploadBg() { bgFileInput.value?.click() }
 function onBgFile(e) {
@@ -159,7 +227,6 @@ function onBgFile(e) {
   if (!f) return
   const reader = new FileReader()
   reader.onload = (ev) => {
-    // 这里只把 dataURL 临时存到 design；正式应上传到后端
     store.patchDesign('background_image', ev.target.result)
   }
   reader.readAsDataURL(f)
@@ -190,7 +257,7 @@ const isNumberCard = computed(() => {
 })
 
 const showImageOffset = computed(() => {
-  return isJoker(store.currentCard) || store.currentCard === 'back'
+  return isJoker(store.currentCard)
 })
 
 const isFaceCard = computed(() => {
@@ -206,8 +273,6 @@ const showSymmetryMode = computed(() => {
 const symmetryMode = computed(() => design.value.symmetry_mode || 'flip')
 
 function setSymmetryMode(v) {
-  // JQK 和大小王都存到 design 里（因为它们是单牌设置）
-  // 但 design 是合并后的，所以用 patchCardOverride 写到当前牌更干净
   store.patchCardOverride(store.currentCard, 'symmetry_mode', v)
 }
 
@@ -251,6 +316,36 @@ function setOffset(i, key, val) {
 function resetLayout() {
   store.resetNumberLayout(String(selectedRank.value))
 }
+
+// ===== 背面相关 =====
+const backImageInput = ref(null)
+function uploadBackImage() { backImageInput.value?.click() }
+function onBackImageFile(e) {
+  const f = e.target.files[0]
+  if (!f) return
+  const reader = new FileReader()
+  reader.onload = (ev) => {
+    store.patchBackDesign('image', ev.target.result)
+  }
+  reader.readAsDataURL(f)
+}
+
+function setBackBgColor(v) { store.patchBackDesign('background_color', v) }
+function setBackDesign(path, v) { store.patchBackDesign(path, v) }
+
+function backImageOffsetVal(key) {
+  const v = Number(backDesign.value[key])
+  if (Number.isNaN(v)) return key === 'image_scale' ? 1 : 0
+  return v
+}
+function setBackImageOffset(key, val) {
+  store.patchBackDesign(key, parseFloat(val))
+}
+function resetBackImageOffset() {
+  store.patchBackDesign('image_dx', 0)
+  store.patchBackDesign('image_dy', 0)
+  store.patchBackDesign('image_scale', 1)
+}
 </script>
 
 <style scoped>