import logging
import sys
import json
from logging.handlers import RotatingFileHandler
import os
from datetime import datetime

# 1. Ensure logs directory exists
LOG_DIR = "logs"
os.makedirs(LOG_DIR, exist_ok=True)

# 2. Custom JSON Formatter
class JsonFormatter(logging.Formatter):
    def format(self, record):
        log_record = {
            "timestamp": datetime.utcfromtimestamp(record.created).isoformat(),
            "level": record.levelname,
            "message": record.getMessage(),
            "module": record.module,
            "function": record.funcName,
            "line": record.lineno,
            "path": record.pathname 
        }
        
        # Add extra fields if available
        if hasattr(record, "request_id"):
            log_record["request_id"] = record.request_id
            
        if record.exc_info:
             log_record["exception"] = self.formatException(record.exc_info)

        return json.dumps(log_record, ensure_ascii=False)

# 3. Setup Logger Function
def setup_logging():
    logger = logging.getLogger("waiting_system")
    logger.setLevel(logging.DEBUG)
    
    # Remove existing handlers to avoid duplicates
    logger.handlers = []

    # Handler 1: Console (Human Readable)
    console_handler = logging.StreamHandler(sys.stdout)
    console_handler.setLevel(logging.INFO)
    console_format = logging.Formatter(
        '%(asctime)s | %(levelname)-8s | %(module)s:%(funcName)s:%(lineno)d - %(message)s'
    )
    console_handler.setFormatter(console_format)
    logger.addHandler(console_handler)

    # Handler 2: File (JSON Structured for Analysis)
    file_handler = RotatingFileHandler(
        os.path.join(LOG_DIR, "system.json.log"),
        maxBytes=10*1024*1024, # 10MB
        backupCount=5,
        encoding='utf-8'
    )
    file_handler.setLevel(logging.DEBUG)
    file_handler.setFormatter(JsonFormatter())
    logger.addHandler(file_handler)
    
    # Handler 3: Human Readable File (Legacy/Easy Read)
    text_handler = RotatingFileHandler(
        os.path.join(LOG_DIR, "system.log"),
        maxBytes=10*1024*1024, # 10MB
        backupCount=5,
        encoding='utf-8'
    )
    text_handler.setLevel(logging.INFO)
    text_handler.setFormatter(console_format)
    logger.addHandler(text_handler)

    return logger

# Singleton Logger Instance
logger = setup_logging()