import os
import requests
import csv
from datetime import datetime, timedelta
import concurrent.futures
import threading
import time

# 1. API 인증키 설정
def get_env_variable(var_name):
    if os.path.exists(".env"):
        with open(".env", "r") as f:
            for line in f:
                if "=" in line:
                    k, v = line.split("=", 1)
                    if k.strip() == var_name:
                        return v.strip()
    return os.getenv(var_name)

API_KEY = get_env_variable("WEATHER_KEY") or get_env_variable("KMA_API_KEY")
TARGET_LAT = 34.925323
TARGET_LON = 127.710838

BASE_URL = "https://apihub.kma.go.kr/api/typ01/url/sfc_nc_var.php"
OBS_ELEMENTS = "ta,hm,td,wd_10m,ws_10m,uu,vv,rn_ox,vs"
INTERVAL = 5 

# 추출 기간
start_dt = datetime(2026, 4, 1, 0, 0)
end_dt = datetime(2026, 5, 7, 23, 55)

def fetch_chunk(tm1, retries=2):
    tm2 = tm1 + timedelta(minutes=55)
    params = {
        "tm1": tm1.strftime("%Y%m%d%H%M"),
        "tm2": tm2.strftime("%Y%m%d%H%M"),
        "obs": OBS_ELEMENTS,
        "itv": INTERVAL,
        "lon": TARGET_LON,
        "lat": TARGET_LAT,
        "help": 0,
        "authKey": API_KEY
    }
    
    for attempt in range(retries):
        try:
            response = requests.get(BASE_URL, params=params, timeout=30)
            response.raise_for_status()
            rows = []
            for line in response.text.strip().split('\n'):
                if line.startswith('#') or not line.strip(): continue
                parts = [p.strip() for p in line.replace(',', ' ').split()]
                if len(parts) >= 10:
                    rows.append({
                        "tm": parts[0],
                        "ta": parts[1],
                        "hm": parts[2],
                        "td": parts[3],
                        "wd_10m": parts[4],
                        "ws_10m": parts[5],
                        "uu": parts[6],
                        "vv": parts[7],
                        "rn_ox": parts[8],
                        "vs": parts[9]
                    })
            return rows
        except Exception:
            if attempt < retries - 1:
                time.sleep(1)
            else:
                return []

def main():
    time_chunks = []
    curr = start_dt
    while curr <= end_dt:
        time_chunks.append(curr)
        curr += timedelta(hours=1)
    
    print(f"--- 연속 데이터 추출 시작 (총 {len(time_chunks)}개 구간, 5개 스레드) ---")
    
    output_filename = "weather_data_continuous_20260401_20260507.csv"
    keys = ["tm", "ta", "hm", "td", "wd_10m", "ws_10m", "uu", "vv", "rn_ox", "vs"]
    
    all_data = []
    completed = 0
    lock = threading.Lock()
    
    with concurrent.futures.ThreadPoolExecutor(max_workers=5) as executor:
        future_to_chunk = {executor.submit(fetch_chunk, t): t for t in time_chunks}
        for future in concurrent.futures.as_completed(future_to_chunk):
            res = future.result()
            if res:
                all_data.extend(res)
            
            completed += 1
            if completed % 20 == 0:
                print(f"  진행 상황: {completed}/{len(time_chunks)} 완료 ({int(completed/len(time_chunks)*100)}%)")

    # 정렬 및 저장
    print("정렬 및 저장 중...")
    all_data.sort(key=lambda x: x['tm'])
    with open(output_filename, 'w', newline='', encoding='utf-8-sig') as f:
        writer = csv.DictWriter(f, fieldnames=keys)
        writer.writeheader()
        writer.writerows(all_data)
    
    print(f"최종 완료: {output_filename} (총 {len(all_data)}행)")

if __name__ == "__main__":
    main()