# command_handler.py
import pandas as pd
from linebot.v3.messaging import TextMessage, ImageMessage

# 匯入服務函式
from cwa_service import fetch_cwa_alarm_list, fetch_significant_earthquakes, fetch_local_earthquakes, fetch_latest_significant_earthquake
from usgs_service import fetch_global_last24h_text, fetch_taiwan_df_this_year
from plotting_service import create_and_save_map
from ai_service import generate_ai_text
from config import CURRENT_YEAR, HF_SPACE_URL

def get_help_message() -> TextMessage:
    """回傳包含所有可用指令的說明訊息。"""
    text = (
        "📖 指令列表\n\n"
        "【地震資訊】\n"
        "• /latest - 查詢最新一筆顯著地震(含圖)\n"
        "• /global - 查詢全球近24小時顯著地震\n"
        "• /taiwan - 顯示今年台灣顯著地震列表\n"
        "• /map - 取得台灣顯著地震地圖連結\n"
        "• /alert - 獲取 CWA 最新地震預警\n"
        "• /significant - CWA 最新顯著有感地震\n"
        "• /local <縣市> - 小區域地震 (可選填縣市)\n\n"
        "【AI 與工具】\n"
        "• /ai <問題> - 與 AI 助理對話\n\n"
        "【基本指令】\n"
        "• /info - 關於此機器人\n"
        "• /help - 顯示此說明"
    )
    return TextMessage(text=text)

def get_info_message() -> TextMessage:
    """回傳機器人資訊。"""
    text = (
        "🤖 關於我\n\n"
        "我是一個多功能助理機器人，提供地震查詢與 AI 對話功能。\n\n"
        "• 版本: 2.5\n"
        "• 資料來源: CWA, USGS, Hugging Face\n"
        "• 開發者: dayichen"
    )
    return TextMessage(text=text)

def get_taiwan_earthquake_list() -> TextMessage:
    """回傳近期的台灣地震文字列表。"""
    result = fetch_taiwan_df_this_year()
    if isinstance(result, pd.DataFrame):
        count = len(result)
        lines = [f"🇹🇼 今年 ({CURRENT_YEAR} 年) 台灣區域顯著地震 (M≥5.0)，共 {count} 筆:", "-" * 20]
        for _, row in result.head(15).iterrows():
            t = row["time_utc"].strftime("%Y-%m-%d %H:%M")
            lines.append(
                f"規模: {row['magnitude']:.1f} | 日期時間: {t} (UTC)\n"
                f"地點: {row['place']}\n"
                f"報告連結: {row.get('url', '無')}"
            )
        if count > 15:
            lines.append(f"... (還有 {count - 15} 筆，請用 /map 查看全部)")
        reply_text = "\n\n".join(lines)
    else:
        reply_text = result
    return TextMessage(text=reply_text)

def get_taiwan_earthquake_map(base_url: str) -> list:
    """產生地震地圖，並回傳包含連結的文字訊息。"""
    result = fetch_taiwan_df_this_year()
    if isinstance(result, pd.DataFrame):
        filename = create_and_save_map(result)
        image_url = f"{(HF_SPACE_URL or base_url)}/static/{filename}"
        reply_text = (
            "🗺️ 已為您繪製地震分佈圖。\n\n"
            "請點擊以下連結查看圖片：\n"
            f"{image_url}"
        )
        return [TextMessage(text=reply_text)]
    else:
        return [TextMessage(text=result)]

def get_latest_earthquake_reply() -> list:
    """獲取最新地震資訊並組合成 LINE 訊息"""
    try:
        latest_eq = fetch_latest_significant_earthquake()
        if not latest_eq:
            return [TextMessage(text="✅ 近期無顯著有感地震報告。")]

        mag_str = f"{latest_eq['Magnitude']:.1f}" if latest_eq.get('Magnitude') is not None else "—"
        depth_str = f"{latest_eq['Depth']:.0f}" if latest_eq.get('Depth') is not None else "—"
        
        text_message_content = (
            f"🚨 CWA 最新顯著有感地震\n"
            f"----------------------------------\n"
            f"時間: {latest_eq.get('TimeStr', '—')}\n"
            f"地點: {latest_eq.get('Location', '—')}\n"
            f"規模: M{mag_str} | 深度: {depth_str} km\n"
            f"報告: {latest_eq.get('URL', '無')}"
        )
        reply_messages = [TextMessage(text=text_message_content)]

        if latest_eq.get("ImageURL"):
            image_url = latest_eq["ImageURL"]
            reply_messages.append(
                ImageMessage(original_content_url=image_url, preview_image_url=image_url)
            )
        
        return reply_messages
    except Exception as e:
        return [TextMessage(text=f"❌ 查詢最新地震失敗：{e}")]

def process_message(user_message_raw: str, request_base_url: str) -> list:
    """處理使用者的文字訊息並回傳一個包含回覆訊息的列表。"""
    user_message = (user_message_raw or "").strip()
    
    # 將舊指令對應到新指令，提供向下相容
    if user_message.lower() in ["地震", "quake"]:
        user_message = "/global"
    elif user_message.lower() in ["台灣地震", "臺灣地震"]:
        user_message = "/taiwan"
    elif user_message.lower() in ["台灣地震畫圖", "臺灣地震畫圖"]:
        user_message = "/map"
    elif user_message.lower() == "地震預警":
        user_message = "/alert"

    if user_message.startswith('/'):
        parts = user_message.split(' ', 1)
        command = parts[0].lower()
        arg = parts[1] if len(parts) > 1 else ""

        if command == '/help':
            return [get_help_message()]
        elif command == '/info':
            return [get_info_message()]
        elif command == '/latest':
            return get_latest_earthquake_reply()
        elif command == '/global':
            return [TextMessage(text=fetch_global_last24h_text())]
        elif command == '/taiwan':
            return [get_taiwan_earthquake_list()]
        elif command == '/map':
            return get_taiwan_earthquake_map(request_base_url)
        elif command == '/alert':
            return [TextMessage(text=fetch_cwa_alarm_list(limit=5))]
        elif command == '/significant':
            return [TextMessage(text=fetch_significant_earthquakes(limit=5))]
        elif command == '/local':
            return [TextMessage(text=fetch_local_earthquakes(area_name=arg))]
        elif command == '/ai':
            if not arg:
                return [TextMessage(text="請輸入問題，例如：/ai 台灣最高的山是哪座？")]
            return [TextMessage(text=generate_ai_text(arg))]

    # 若非指令，則預設交給 AI 處理 (作為備援)
    return [TextMessage(text=generate_ai_text(user_message))]