feat: 完善结局页AI改写体验（配额检查/加载动画/历史记录）

client/js/scenes/EndingScene.js

@@ -18,7 +18,16 @@ export default class EndingScene extends BaseScene {
     this.rewritePrompt = '';
     this.rewriteTags = ['主角逆袭', '甜蜜HE', '虐心BE', '反转剧情', '意外重逢'];
     this.selectedTag = -1;
+    // 改写历史
+    this.rewriteHistory = [];
+    this.currentHistoryIndex = -1;
+    // 配额信息
+    this.aiQuota = { daily: 3, used: 0, purchased: 0 };
+    // 加载状态
+    this.isRewriting = false;
+    this.rewriteProgress = 0;
     this.initParticles();
+    this.loadQuota();
   }
 
   init() {
@@ -27,6 +36,17 @@ export default class EndingScene extends BaseScene {
     }, 1500);
   }
 
+  async loadQuota() {
+    try {
+      const quota = await this.main.userManager.getAIQuota();
+      if (quota) {
+        this.aiQuota = quota;
+      }
+    } catch (e) {
+      console.error('加载配额失败:', e);
+    }
+  }
+
   initParticles() {
     for (let i = 0; i < 50; i++) {
       this.particles.push({
@@ -228,13 +248,15 @@ export default class EndingScene extends BaseScene {
     const buttonHeight = 38;
     const buttonMargin = 8;
     const startY = this.screenHeight - 220;
-    const buttonWidth = (this.screenWidth - padding * 2 - buttonMargin) / 2;
 
-    // AI改写按钮（突出显示）
-    this.renderGradientButton(ctx, padding, startY, this.screenWidth - padding * 2, buttonHeight, '✨ AI改写结局', ['#a855f7', '#ec4899']);
+    // AI改写按钮（带配额提示）
+    const remaining = this.aiQuota.daily - this.aiQuota.used + this.aiQuota.purchased;
+    const aiBtnText = remaining > 0 ? '✨ AI改写结局' : '⚠️ 次数不足';
+    this.renderGradientButton(ctx, padding, startY, this.screenWidth - padding * 2, buttonHeight, aiBtnText, ['#a855f7', '#ec4899']);
 
     // 分享按钮
     const row2Y = startY + buttonHeight + buttonMargin;
+    const buttonWidth = (this.screenWidth - padding * 2 - buttonMargin) / 2;
     this.renderGradientButton(ctx, padding, row2Y, buttonWidth, buttonHeight, '分享结局', ['#ff6b6b', '#ffd700']);
 
     // 章节选择按钮
@@ -298,12 +320,12 @@ export default class EndingScene extends BaseScene {
   renderRewritePanel(ctx) {
     const padding = 20;
     const panelWidth = this.screenWidth - padding * 2;
-    const panelHeight = 380;
+    const panelHeight = 450;
     const panelX = padding;
     const panelY = (this.screenHeight - panelHeight) / 2;
 
     // 遮罩层
-    ctx.fillStyle = 'rgba(0, 0, 0, 0.8)';
+    ctx.fillStyle = 'rgba(0, 0, 0, 0.85)';
     ctx.fillRect(0, 0, this.screenWidth, this.screenHeight);
 
     // 面板背景渐变
@@ -323,15 +345,23 @@ export default class EndingScene extends BaseScene {
     this.roundRect(ctx, panelX, panelY, panelWidth, panelHeight, 20);
     ctx.stroke();
 
-    // 标题
+    // 标题栏
     ctx.fillStyle = '#ffffff';
     ctx.font = 'bold 18px sans-serif';
     ctx.textAlign = 'center';
     ctx.fillText('✨ AI改写结局', this.screenWidth / 2, panelY + 35);
 
+    // 配额提示
+    const remaining = this.aiQuota.daily - this.aiQuota.used + this.aiQuota.purchased;
+    ctx.fillStyle = remaining > 0 ? 'rgba(255,255,255,0.6)' : 'rgba(255,100,100,0.8)';
+    ctx.font = '11px sans-serif';
+    ctx.textAlign = 'right';
+    ctx.fillText(`剩余次数：${remaining}`, panelX + panelWidth - 15, panelY + 35);
+
     // 副标题
     ctx.fillStyle = 'rgba(255,255,255,0.6)';
     ctx.font = '12px sans-serif';
+    ctx.textAlign = 'center';
     ctx.fillText('输入你想要的剧情走向，AI将为你重新创作', this.screenWidth / 2, panelY + 58);
 
     // 分隔线
@@ -641,6 +671,13 @@ export default class EndingScene extends BaseScene {
   }
 
   handleAIRewrite() {
+    // 检查配额
+    const remaining = this.aiQuota.daily - this.aiQuota.used + this.aiQuota.purchased;
+    if (remaining <= 0) {
+      this.showQuotaModal();
+      return;
+    }
+    
     // 显示AI改写面板
     this.showRewritePanel = true;
     this.rewritePrompt = '';
@@ -701,7 +738,27 @@ export default class EndingScene extends BaseScene {
   }
 
   async callAIRewrite(prompt) {
-    wx.showLoading({ title: 'AI创作中...' });
+    // 检查配额
+    const remaining = this.aiQuota.daily - this.aiQuota.used + this.aiQuota.purchased;
+    if (remaining <= 0) {
+      this.showQuotaModal();
+      return;
+    }
+
+    this.isRewriting = true;
+    this.rewriteProgress = 0;
+    
+    // 显示加载动画
+    wx.showLoading({ 
+      title: 'AI创作中...',
+      mask: true
+    });
+
+    // 模拟进度条效果
+    const progressInterval = setInterval(() => {
+      this.rewriteProgress += Math.random() * 20;
+      if (this.rewriteProgress > 90) this.rewriteProgress = 90;
+    }, 500);
     
     try {
       const result = await this.main.storyManager.rewriteEnding(
@@ -710,23 +767,73 @@ export default class EndingScene extends BaseScene {
         prompt
       );
       
+      clearInterval(progressInterval);
+      this.rewriteProgress = 100;
       wx.hideLoading();
       
       if (result && result.content) {
-        // 跳转到故事场景播放新内容
-        this.main.sceneManager.switchScene('story', {
-          storyId: this.storyId,
-          aiContent: result
+        // 记录改写历史
+        this.rewriteHistory.push({
+          prompt: prompt,
+          content: result.content,
+          timestamp: Date.now()
         });
+        this.currentHistoryIndex = this.rewriteHistory.length - 1;
+        
+        // 扣除配额
+        this.aiQuota.used += 1;
+        
+        // 成功提示
+        wx.showToast({ 
+          title: '改写成功！', 
+          icon: 'success',
+          duration: 1500
+        });
+        
+        // 延迟跳转到故事场景播放新内容
+        setTimeout(() => {
+          this.main.sceneManager.switchScene('story', {
+            storyId: this.storyId,
+            aiContent: result
+          });
+        }, 1500);
       } else {
         wx.showToast({ title: '改写失败，请重试', icon: 'none' });
       }
     } catch (error) {
+      clearInterval(progressInterval);
       wx.hideLoading();
-      wx.showToast({ title: '网络错误', icon: 'none' });
+      console.error('改写失败:', error);
+      wx.showToast({ title: error.message || '网络错误', icon: 'none' });
+    } finally {
+      this.isRewriting = false;
+      this.rewriteProgress = 0;
     }
   }
 
+  showQuotaModal() {
+    wx.showModal({
+      title: 'AI次数不足',
+      content: `今日剩余免费次数已用完。\n\n观看广告可获得1次 AI改写机会`,
+      confirmText: '看广告',
+      cancelText: '取消',
+      success: (res) => {
+        if (res.confirm) {
+          this.watchAdForQuota();
+        }
+      }
+    });
+  }
+
+  watchAdForQuota() {
+    // 模拟看广告获得配额
+    wx.showToast({ 
+      title: '获得1次 AI 次数', 
+      icon: 'success' 
+    });
+    this.aiQuota.purchased += 1;
+  }
+
   handleReplay() {
     this.main.storyManager.resetStory();
     this.main.sceneManager.switchScene('story', { storyId: this.storyId });