import gzip
import logging
import logging.handlers
import os
import shutil
from pathlib import Path

LOG_DIR = os.getenv("LOG_DIR", "logs")
LOG_LEVEL = os.getenv("LOG_LEVEL", "INFO").upper()
Path(LOG_DIR).mkdir(parents=True, exist_ok=True)
LOG_FILE = os.path.join(LOG_DIR, "AutoCoinTrader.log")

logger = logging.getLogger("macd_alarm")
_logger_configured = False

# 거래소 및 계산 상수
# 부동소수점 비교용 엡실론 (일반적 정밀도)
FLOAT_EPSILON = 1e-10

# 거래소별 최소 수량 (Upbit 기준)
MIN_TRADE_AMOUNT = 1e-8  # 0.00000001 (암호화폐 최소 단위)

# 최소 주문 금액 (KRW)
MIN_KRW_ORDER = 5000  # Upbit 최소 주문 금액

# 데이터 파일 경로 상수 (중앙 집중 관리)
DATA_DIR = Path("data")
DATA_DIR.mkdir(parents=True, exist_ok=True)
HOLDINGS_FILE = str(DATA_DIR / "holdings.json")
TRADES_FILE = str(DATA_DIR / "trades.json")
PENDING_ORDERS_FILE = str(DATA_DIR / "pending_orders.json")


class CompressedRotatingFileHandler(logging.handlers.RotatingFileHandler):
    """RotatingFileHandler with gzip compression for rotated logs."""

    def rotation_filename(self, default_name):
        """Append .gz to rotated log files."""
        return default_name + ".gz"

    def rotate(self, source, dest):
        """Compress the rotated log file."""
        if os.path.exists(source):
            with open(source, "rb") as f_in:
                with gzip.open(dest, "wb") as f_out:
                    shutil.copyfileobj(f_in, f_out)
            os.remove(source)


def setup_logger(dry_run: bool):
    """
    Configure logging with rotation and compression.

    Args:
        dry_run: If True, also output to console. If False, only to file.

    Log Rotation Strategy:
        - Size-based: 10MB per file, keep 7 backups (total ~80MB)
        - Compression: Old logs are gzipped (saves ~70% space)

    Log Levels (production recommendation):
        - dry_run=True: INFO (development/testing)
        - dry_run=False: INFO (production - retain important trading logs)

    ⚠️ CRITICAL: Production mode uses INFO level to ensure trading events are logged.
       This is essential for auditing buy/sell orders and debugging issues.
       For high-volume environments, adjust LOG_LEVEL via environment variable.
    """
    global logger, _logger_configured
    if _logger_configured:
        return

    logger.handlers.clear()

    # Use INFO level for both dry_run and production to ensure trading events are logged
    # Production systems can override via LOG_LEVEL environment variable if needed
    effective_level = getattr(logging, LOG_LEVEL, logging.INFO)
    logger.setLevel(effective_level)

    formatter = logging.Formatter("%(asctime)s - %(levelname)s - [%(threadName)s] - %(message)s")

    # Console handler (only in dry_run mode)
    if dry_run:
        ch = logging.StreamHandler()
        ch.setLevel(effective_level)
        ch.setFormatter(formatter)
        logger.addHandler(ch)

    # Size-based rotating file handler with compression (only one rotation strategy)
    fh_size = CompressedRotatingFileHandler(
        LOG_FILE,
        maxBytes=10 * 1024 * 1024,
        backupCount=7,
        encoding="utf-8",  # 10MB per file  # Keep 7 backups
    )
    fh_size.setLevel(effective_level)
    fh_size.setFormatter(formatter)
    logger.addHandler(fh_size)

    _logger_configured = True

    logger.info(
        "[SYSTEM] 로그 설정 완료: level=%s, size_rotation=%dMB×%d (일별 로테이션 제거됨)",
        logging.getLevelName(effective_level),
        10,
        7,
    )