//
//  KBAiChatView.m
//  keyBoard
//
//  Created by Mac on 2026/1/15.
//

#import "KBAiChatView.h"

#pragma mark - KBAiChatBubbleCell

@interface KBAiChatBubbleCell : UITableViewCell
@property(nonatomic, strong) UIView *bubbleView;
@property(nonatomic, strong) UILabel *messageLabel;
@property(nonatomic, assign) KBAiChatMessageType messageType;
@end

@implementation KBAiChatBubbleCell

- (instancetype)initWithStyle:(UITableViewCellStyle)style
              reuseIdentifier:(NSString *)reuseIdentifier {
  self = [super initWithStyle:style reuseIdentifier:reuseIdentifier];
  if (self) {
    self.backgroundColor = [UIColor clearColor];
    self.selectionStyle = UITableViewCellSelectionStyleNone;

    // 气泡视图
    self.bubbleView = [[UIView alloc] init];
    self.bubbleView.layer.cornerRadius = 16;
    self.bubbleView.layer.masksToBounds = YES;
    self.bubbleView.translatesAutoresizingMaskIntoConstraints = NO;
    [self.contentView addSubview:self.bubbleView];

    // 消息标签
    self.messageLabel = [[UILabel alloc] init];
    self.messageLabel.numberOfLines = 0;
    self.messageLabel.font = [UIFont systemFontOfSize:16];
    self.messageLabel.translatesAutoresizingMaskIntoConstraints = NO;
    [self.bubbleView addSubview:self.messageLabel];

    // 消息标签约束
    [NSLayoutConstraint activateConstraints:@[
      [self.messageLabel.topAnchor
          constraintEqualToAnchor:self.bubbleView.topAnchor
                         constant:10],
      [self.messageLabel.bottomAnchor
          constraintEqualToAnchor:self.bubbleView.bottomAnchor
                         constant:-10],
      [self.messageLabel.leadingAnchor
          constraintEqualToAnchor:self.bubbleView.leadingAnchor
                         constant:12],
      [self.messageLabel.trailingAnchor
          constraintEqualToAnchor:self.bubbleView.trailingAnchor
                         constant:-12],
    ]];
  }
  return self;
}

- (void)configureWithMessage:(KBAiChatMessage *)message {
  self.messageLabel.text = message.text;
  self.messageType = message.type;

  // 移除旧约束
  for (NSLayoutConstraint *constraint in self.bubbleView.constraints) {
    if (constraint.firstAttribute == NSLayoutAttributeWidth) {
      constraint.active = NO;
    }
  }

  // 根据消息类型设置样式
  if (message.type == KBAiChatMessageTypeUser) {
    // 用户消息：右对齐，主题色背景
    self.bubbleView.backgroundColor = [UIColor systemBlueColor];
    self.messageLabel.textColor = [UIColor whiteColor];

    [NSLayoutConstraint deactivateConstraints:self.bubbleView.constraints];
    [NSLayoutConstraint activateConstraints:@[
      [self.bubbleView.topAnchor
          constraintEqualToAnchor:self.contentView.topAnchor
                         constant:4],
      [self.bubbleView.bottomAnchor
          constraintEqualToAnchor:self.contentView.bottomAnchor
                         constant:-4],
      [self.bubbleView.trailingAnchor
          constraintEqualToAnchor:self.contentView.trailingAnchor
                         constant:-16],
      [self.bubbleView.widthAnchor
          constraintLessThanOrEqualToAnchor:self.contentView.widthAnchor
                                 multiplier:0.75],

      [self.messageLabel.topAnchor
          constraintEqualToAnchor:self.bubbleView.topAnchor
                         constant:10],
      [self.messageLabel.bottomAnchor
          constraintEqualToAnchor:self.bubbleView.bottomAnchor
                         constant:-10],
      [self.messageLabel.leadingAnchor
          constraintEqualToAnchor:self.bubbleView.leadingAnchor
                         constant:12],
      [self.messageLabel.trailingAnchor
          constraintEqualToAnchor:self.bubbleView.trailingAnchor
                         constant:-12],
    ]];
  } else {
    // AI 消息：左对齐，浅灰色背景
    self.bubbleView.backgroundColor = [UIColor systemGray5Color];
    self.messageLabel.textColor = [UIColor labelColor];

    [NSLayoutConstraint deactivateConstraints:self.bubbleView.constraints];
    [NSLayoutConstraint activateConstraints:@[
      [self.bubbleView.topAnchor
          constraintEqualToAnchor:self.contentView.topAnchor
                         constant:4],
      [self.bubbleView.bottomAnchor
          constraintEqualToAnchor:self.contentView.bottomAnchor
                         constant:-4],
      [self.bubbleView.leadingAnchor
          constraintEqualToAnchor:self.contentView.leadingAnchor
                         constant:16],
      [self.bubbleView.widthAnchor
          constraintLessThanOrEqualToAnchor:self.contentView.widthAnchor
                                 multiplier:0.75],

      [self.messageLabel.topAnchor
          constraintEqualToAnchor:self.bubbleView.topAnchor
                         constant:10],
      [self.messageLabel.bottomAnchor
          constraintEqualToAnchor:self.bubbleView.bottomAnchor
                         constant:-10],
      [self.messageLabel.leadingAnchor
          constraintEqualToAnchor:self.bubbleView.leadingAnchor
                         constant:12],
      [self.messageLabel.trailingAnchor
          constraintEqualToAnchor:self.bubbleView.trailingAnchor
                         constant:-12],
    ]];
  }
}

@end

#pragma mark - KBAiChatView

@interface KBAiChatView () <UITableViewDataSource, UITableViewDelegate>
@property(nonatomic, strong) UITableView *tableView;
@property(nonatomic, strong) NSMutableArray<KBAiChatMessage *> *messages;
@end

@implementation KBAiChatView

- (instancetype)initWithFrame:(CGRect)frame {
  self = [super initWithFrame:frame];
  if (self) {
    [self setup];
  }
  return self;
}

- (instancetype)initWithCoder:(NSCoder *)coder {
  self = [super initWithCoder:coder];
  if (self) {
    [self setup];
  }
  return self;
}

- (void)setup {
  self.messages = [[NSMutableArray alloc] init];

  self.tableView = [[UITableView alloc] initWithFrame:self.bounds
                                                style:UITableViewStylePlain];
  self.tableView.autoresizingMask =
      UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
  self.tableView.dataSource = self;
  self.tableView.delegate = self;
  self.tableView.separatorStyle = UITableViewCellSeparatorStyleNone;
  self.tableView.backgroundColor = [UIColor clearColor];
  self.tableView.estimatedRowHeight = 60;
  self.tableView.rowHeight = UITableViewAutomaticDimension;
  [self.tableView registerClass:[KBAiChatBubbleCell class]
         forCellReuseIdentifier:@"ChatCell"];
  [self addSubview:self.tableView];
}

#pragma mark - Public Methods

- (void)addUserMessage:(NSString *)text {
  KBAiChatMessage *message = [KBAiChatMessage userMessageWithText:text];
  [self.messages addObject:message];

  [self.tableView reloadData];
  [self scrollToBottom];
}

- (void)addAssistantMessage:(NSString *)text {
  KBAiChatMessage *message = [KBAiChatMessage assistantMessageWithText:text];
  [self.messages addObject:message];

  [self.tableView reloadData];
  [self scrollToBottom];
}

- (void)updateLastAssistantMessage:(NSString *)text {
  // 查找最后一条 AI 消息
  for (NSInteger i = self.messages.count - 1; i >= 0; i--) {
    KBAiChatMessage *message = self.messages[i];
    if (message.type == KBAiChatMessageTypeAssistant && !message.isComplete) {
      message.text = text;

      NSIndexPath *indexPath = [NSIndexPath indexPathForRow:i inSection:0];
      [self.tableView reloadRowsAtIndexPaths:@[ indexPath ]
                            withRowAnimation:UITableViewRowAnimationNone];
      return;
    }
  }

  // 如果没找到，添加新消息
  [self addAssistantMessage:text];
}

- (void)markLastAssistantMessageComplete {
  for (NSInteger i = self.messages.count - 1; i >= 0; i--) {
    KBAiChatMessage *message = self.messages[i];
    if (message.type == KBAiChatMessageTypeAssistant) {
      message.isComplete = YES;
      return;
    }
  }
}

- (void)clearMessages {
  [self.messages removeAllObjects];
  [self.tableView reloadData];
}

- (void)scrollToBottom {
  if (self.messages.count == 0)
    return;

  NSIndexPath *lastIndexPath =
      [NSIndexPath indexPathForRow:self.messages.count - 1 inSection:0];
  [self.tableView scrollToRowAtIndexPath:lastIndexPath
                        atScrollPosition:UITableViewScrollPositionBottom
                                animated:YES];
}

#pragma mark - UITableViewDataSource

- (NSInteger)tableView:(UITableView *)tableView
    numberOfRowsInSection:(NSInteger)section {
  return self.messages.count;
}

- (UITableViewCell *)tableView:(UITableView *)tableView
         cellForRowAtIndexPath:(NSIndexPath *)indexPath {
  KBAiChatBubbleCell *cell =
      [tableView dequeueReusableCellWithIdentifier:@"ChatCell"
                                      forIndexPath:indexPath];

  KBAiChatMessage *message = self.messages[indexPath.row];
  [cell configureWithMessage:message];

  return cell;
}

#pragma mark - UITableViewDelegate

- (CGFloat)tableView:(UITableView *)tableView
    estimatedHeightForRowAtIndexPath:(NSIndexPath *)indexPath {
  return 60;
}

@end