新增聊天记录

keyBoard/Class/AiTalk/V/KBPersonaChatCell.m

@@ -8,6 +8,8 @@
 #import "KBPersonaChatCell.h"
 #import "KBChatTableView.h"
 #import "KBAiChatMessage.h"
+#import "KBChatHistoryPageModel.h"
+#import "AiVM.h"
 #import <Masonry/Masonry.h>
 #import <SDWebImage/SDWebImage.h>
 
@@ -34,6 +36,18 @@
 /// 是否已加载数据
 @property (nonatomic, assign) BOOL hasLoadedData;
 
+/// 是否正在加载
+@property (nonatomic, assign) BOOL isLoading;
+
+/// 当前页码
+@property (nonatomic, assign) NSInteger currentPage;
+
+/// 是否还有更多历史消息
+@property (nonatomic, assign) BOOL hasMoreHistory;
+
+/// AiVM 实例
+@property (nonatomic, strong) AiVM *aiVM;
+
 @end
 
 @implementation KBPersonaChatCell
@@ -102,7 +116,11 @@
     
     // 重置状态
     self.hasLoadedData = NO;
+    self.isLoading = NO;
+    self.currentPage = 1;
+    self.hasMoreHistory = YES;
     self.messages = [NSMutableArray array];
+    self.aiVM = [[AiVM alloc] init];
     
     // 设置 UI
     [self.backgroundImageView sd_setImageWithURL:[NSURL URLWithString:persona.coverImageUrl]
@@ -118,20 +136,113 @@
 #pragma mark - 2：数据加载
 
 - (void)preloadDataIfNeeded {
-    if (self.hasLoadedData) {
+    if (self.hasLoadedData || self.isLoading) {
         return;
     }
     
-    // TODO: 这里后续需要用 chatId 去请求聊天记录
-    // 目前先添加开场白作为第一条消息
-    self.hasLoadedData = YES;
-    
-    if (self.persona.introText.length > 0) {
-        KBAiChatMessage *openingMsg = [KBAiChatMessage assistantMessageWithText:self.persona.introText];
-        openingMsg.isComplete = YES;
-        [self.messages addObject:openingMsg];
-        [self.tableView reloadData];
+    [self loadChatHistory];
+}
+
+- (void)loadChatHistory {
+    if (self.isLoading || !self.hasMoreHistory) {
+        return;
     }
+    
+    self.isLoading = YES;
+    
+    // 使用 persona.personaId 作为 companionId
+    NSInteger companionId = self.persona.personaId;
+    
+    __weak typeof(self) weakSelf = self;
+    [self.aiVM fetchChatHistoryWithCompanionId:companionId
+                                        pageNum:self.currentPage
+                                       pageSize:20
+                                     completion:^(KBChatHistoryPageModel *pageModel, NSError *error) {
+        weakSelf.isLoading = NO;
+        
+        if (error) {
+            NSLog(@"[KBPersonaChatCell] 加载聊天记录失败：%@", error.localizedDescription);
+            
+            // 如果是第一次加载失败，显示开场白
+            if (weakSelf.currentPage == 1 && weakSelf.persona.introText.length > 0) {
+                [weakSelf showOpeningMessage];
+            }
+            return;
+        }
+        
+        weakSelf.hasLoadedData = YES;
+        weakSelf.hasMoreHistory = pageModel.hasMore;
+        
+        // 转换为 KBAiChatMessage
+        NSMutableArray *newMessages = [NSMutableArray array];
+        for (KBChatHistoryModel *item in pageModel.records) {
+            KBAiChatMessage *message;
+            if (item.isUserMessage) {
+                message = [KBAiChatMessage userMessageWithText:item.content];
+            } else {
+                message = [KBAiChatMessage assistantMessageWithText:item.content];
+            }
+            message.isComplete = YES;
+            [newMessages addObject:message];
+        }
+        
+        // 插入到顶部（历史消息）
+        if (weakSelf.currentPage == 1) {
+            // 第一页，直接赋值
+            weakSelf.messages = newMessages;
+        } else {
+            // 后续页，插入到顶部
+            NSIndexSet *indexSet = [NSIndexSet indexSetWithIndexesInRange:NSMakeRange(0, newMessages.count)];
+            [weakSelf.messages insertObjects:newMessages atIndexes:indexSet];
+        }
+        
+        // 刷新 UI
+        dispatch_async(dispatch_get_main_queue(), ^{
+            if (weakSelf.currentPage == 1) {
+                [weakSelf.tableView reloadData];
+                
+                // 滚动到底部（最新消息）
+                if (weakSelf.messages.count > 0) {
+                    NSIndexPath *lastIndexPath = [NSIndexPath indexPathForRow:weakSelf.messages.count - 1 inSection:0];
+                    [weakSelf.tableView scrollToRowAtIndexPath:lastIndexPath
+                                              atScrollPosition:UITableViewScrollPositionBottom
+                                                      animated:NO];
+                }
+            } else {
+                // 保持滚动位置
+                CGFloat oldContentHeight = weakSelf.tableView.contentSize.height;
+                [weakSelf.tableView reloadData];
+                CGFloat newContentHeight = weakSelf.tableView.contentSize.height;
+                CGFloat offsetY = newContentHeight - oldContentHeight;
+                [weakSelf.tableView setContentOffset:CGPointMake(0, offsetY) animated:NO];
+            }
+        });
+        
+        NSLog(@"[KBPersonaChatCell] 加载成功：第 %ld 页，%ld 条消息，还有更多：%@",
+              (long)weakSelf.currentPage,
+              (long)newMessages.count,
+              pageModel.hasMore ? @"是" : @"否");
+    }];
+}
+
+- (void)loadMoreHistory {
+    if (!self.hasMoreHistory || self.isLoading) {
+        return;
+    }
+    
+    self.currentPage++;
+    [self loadChatHistory];
+}
+
+- (void)showOpeningMessage {
+    // 显示开场白作为第一条消息
+    KBAiChatMessage *openingMsg = [KBAiChatMessage assistantMessageWithText:self.persona.introText];
+    openingMsg.isComplete = YES;
+    [self.messages addObject:openingMsg];
+    
+    dispatch_async(dispatch_get_main_queue(), ^{
+        [self.tableView reloadData];
+    });
 }
 
 #pragma mark - UITableViewDataSource
@@ -159,6 +270,17 @@
     return UITableViewAutomaticDimension;
 }
 
+#pragma mark - UIScrollViewDelegate
+
+- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
+    CGFloat offsetY = scrollView.contentOffset.y;
+    
+    // 下拉到顶部，加载历史消息
+    if (offsetY <= -50 && !self.isLoading) {
+        [self loadMoreHistory];
+    }
+}
+
 #pragma mark - Lazy Load
 
 - (UIImageView *)backgroundImageView {