import gradio as gr
import json
import requests
import time
import datetime
import pytz
import csv
import traceback
import threading
import os

OUTPUT_FILE = "/data/data3.csv"
status_logs = ["⏳ 系統啟動，等待第一次抓取資料..."]

def update_log(message):
    global status_logs
    status_logs.append(message)
    if len(status_logs) > 15:
        status_logs = status_logs[-15:]

def fetch_and_append_data():
    url = "https://www.chinamoney.com.cn/r/cms/www/chinamoney/data/fx/rfx-sp-quot.json"
    beijing_tz = pytz.timezone('Asia/Shanghai')
    current_time = datetime.datetime.now(beijing_tz).strftime('%Y-%m-%d %H:%M:%S')
    
    try:
        dir_name = os.path.dirname(OUTPUT_FILE)
        if dir_name and not os.path.exists(dir_name):
            os.makedirs(dir_name, exist_ok=True)

        headers = {
            'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36'
        }
        response = requests.get(url, headers=headers)
        response.raise_for_status()
        data = response.json()

        items = data.get('records', [])
        if not items:
            update_log(f"[{current_time}] ⚠️ 抓取成功，但找不到 records 資料。")
            return

        headers_csv = None
        try:
            with open(OUTPUT_FILE, 'r', newline='', encoding='utf-8') as f:
                reader = csv.reader(f)
                first_row = next(reader, None)
                if first_row:
                    headers_csv = first_row
        except (FileNotFoundError, StopIteration):
            pass 

        with open(OUTPUT_FILE, 'a', newline='', encoding='utf-8') as csvfile:
            writer = csv.writer(csvfile)

            if not headers_csv:
                if items and isinstance(items[0], dict):
                     headers_csv = list(items[0].keys()) + ['timestamp']
                     writer.writerow(headers_csv) 
                else:
                     update_log(f"[{current_time}] ❌ 無法判斷資料結構，跳過寫入。")
                     return

            for item in items:
                if isinstance(item, dict):
                    row = [item.get(header, '') for header in headers_csv[:-1]] 
                    row.append(current_time) 
                    writer.writerow(row)

        update_log(f"[{current_time}] ✅ 成功抓取並寫入 {len(items)} 筆資料！")

    except requests.exceptions.RequestException as e:
        update_log(f"[{current_time}] ❌ 網路請求錯誤: {e}")
    except Exception as e:
        update_log(f"[{current_time}] ❌ 寫入或執行失敗: {str(e)}")

def background_task():
    while True:
        fetch_and_append_data()
        time.sleep(300)

thread = threading.Thread(target=background_task, daemon=True)
thread.start()

def refresh_all_data():
    logs = "\n".join(status_logs)
    file_exists = os.path.exists(OUTPUT_FILE) and os.path.isfile(OUTPUT_FILE)
    
    # 優化：如果檔案不存在回傳 None，避免 Gradio 讀取空值崩潰
    file_output = OUTPUT_FILE if file_exists else None
    
    preview = "檔案尚未建立或尚無資料..."
    if file_exists:
        try:
            with open(OUTPUT_FILE, 'r', encoding='utf-8') as f:
                lines = f.readlines()
                if len(lines) <= 10:
                    preview = "".join(lines)
                else:
                    preview = lines[0] + "...\n(中間省略)\n...\n" + "".join(lines[-10:])
        except Exception as e:
            preview = f"讀取預覽檔案時失敗: {e}"
            
    return logs, file_output, preview

with gr.Blocks(title="資料自動抓取工具") as demo:
    gr.Markdown("# 📈 外匯報價自動抓取系統")
    gr.Markdown("此程式會在背景 **每 5 分鐘** 自動向目標網站請求資料，並寫入 CSV。")
    
    with gr.Row():
        with gr.Column():
            log_box = gr.Textbox(label="後台執行狀態", lines=10, value="\n".join(status_logs), interactive=False)
            refresh_btn = gr.Button("🔄 刷新狀態與資料", variant="primary")
            
        with gr.Column():
            download_btn = gr.File(label="下載當前的 CSV 檔案")
            preview_box = gr.Textbox(label="資料預覽 (顯示最後幾筆)", lines=10, value="點擊刷新按鈕載入預覽...", interactive=False)

    refresh_btn.click(
        fn=refresh_all_data,
        inputs=None,
        outputs=[log_box, download_btn, preview_box]
    )

if __name__ == "__main__":
    # 關鍵修復：加入 allowed_paths=["/data"]，允許 Gradio 提供 Storage Bucket 裡的檔案給使用者下載
    demo.launch(allowed_paths=["/data"])