backend/utils/line_utils.py

"""
LINE Bot 相關工具函數
"""

from linebot.models import (
    TextSendMessage, QuickReply, QuickReplyButton, MessageAction,
    FlexSendMessage, BubbleContainer, BoxComponent, TextComponent,
    ButtonComponent, URIAction
)
from typing import List, Dict, Any
import logging

logger = logging.getLogger(__name__)

class LineMessageBuilder:
    """LINE 訊息建構器"""
    
    @staticmethod
    def create_quick_reply_message(text: str, quick_reply_items: List[Dict[str, str]]) -> TextSendMessage:
        """建立快速回覆訊息"""
        quick_reply_buttons = []
        
        for item in quick_reply_items:
            button = QuickReplyButton(
                action=MessageAction(
                    label=item["label"],
                    text=item["text"]
                )
            )
            quick_reply_buttons.append(button)
        
        quick_reply = QuickReply(items=quick_reply_buttons)
        
        return TextSendMessage(
            text=text,
            quick_reply=quick_reply
        )
    
    @staticmethod
    def create_product_flex_message(products: List[Dict[str, Any]]) -> FlexSendMessage:
        """建立商品展示的 Flex 訊息"""
        contents = []
        
        for product in products[:10]:  # 最多顯示10個商品
            bubble = BubbleContainer(
                body=BoxComponent(
                    layout="vertical",
                    contents=[
                        TextComponent(
                            text=product.get("name", "商品名稱"),
                            weight="bold",
                            size="lg"
                        ),
                        TextComponent(
                            text=f"NT$ {product.get('price', 0):,}",
                            size="md",
                            color="#ff5551"
                        ),
                        TextComponent(
                            text=f"庫存: {product.get('stock', 0)}",
                            size="sm",
                            color="#aaaaaa"
                        )
                    ]
                ),
                footer=BoxComponent(
                    layout="vertical",
                    contents=[
                        ButtonComponent(
                            action=MessageAction(
                                label="查看詳情",
                                text=f"查詢商品 {product.get('name', '')}"
                            ),
                            style="primary"
                        )
                    ]
                )
            )
            contents.append(bubble)
        
        return FlexSendMessage(
            alt_text="商品列表",
            contents={
                "type": "carousel",
                "contents": [bubble.as_json_dict() for bubble in contents]
            }
        )
    
    @staticmethod
    def create_help_message() -> TextSendMessage:
        """建立說明訊息"""
        help_text = """
🤖 歡迎使用智能查詢機器人！

📝 支援的查詢類型：
• 用戶查詢：「查詢用戶 張三」
• 訂單查詢：「查詢訂單 ORD001」
• 商品查詢：「查詢商品 iPhone」
• 價格範圍：「價格 1000 到 5000 的商品」
• 統計分析：「統計用戶數量」

💡 使用範例：
• 「找用戶名叫王小明的資料」
• 「我的訂單狀態如何」
• 「有什麼手機商品」
• 「總共有多少筆訂單」

❓ 如需協助，請輸入「幫助」或「說明」
        """
        
        quick_reply_items = [
            {"label": "查詢用戶", "text": "查詢用戶"},
            {"label": "查詢訂單", "text": "查詢訂單"},
            {"label": "查詢商品", "text": "查詢商品"},
            {"label": "統計資料", "text": "統計"}
        ]
        
        return LineMessageBuilder.create_quick_reply_message(help_text, quick_reply_items)
    
    @staticmethod
    def create_error_message(error_msg: str = None) -> TextSendMessage:
        """建立錯誤訊息"""
        default_msg = "抱歉，我無法理解您的訊息。請輸入「幫助」查看使用說明。"
        text = error_msg if error_msg else default_msg
        
        quick_reply_items = [
            {"label": "幫助", "text": "幫助"},
            {"label": "重新開始", "text": "開始"}
        ]
        
        return LineMessageBuilder.create_quick_reply_message(text, quick_reply_items)

def get_user_display_name(line_bot_api, user_id: str) -> str:
    """取得用戶顯示名稱"""
    try:
        profile = line_bot_api.get_profile(user_id)
        return profile.display_name
    except Exception as e:
        logger.error(f"取得用戶資料失敗: {str(e)}")
        return "用戶"

def validate_line_signature(body: bytes, signature: str, channel_secret: str) -> bool:
    """驗證 LINE Webhook 簽名"""
    import hashlib
    import hmac
    import base64
    
    hash_value = hmac.new(
        channel_secret.encode('utf-8'),
        body,
        hashlib.sha256
    ).digest()
    
    expected_signature = base64.b64encode(hash_value).decode('utf-8')
    return hmac.compare_digest(signature, expected_signature)