"""
Logging configuration for VideoDetect.

Sets up JSON structured logging via python-json-logger with:
- Configurable log levels
- Standardized field names
- Log rotation
- All logs to stdout for Docker capture
"""

import json
import logging
import logging.handlers
import sys
from datetime import datetime, timezone

from python_json_logger import json_formatter


def setup_logging(
    level: str = "INFO",
    log_format: str = "json",
    rotation_max_bytes: int = 104857600,  # 100MB
    rotation_backup_count: int = 10,
):
    """Configure structured logging for the application."""
    log_level = getattr(logging, level.upper(), logging.INFO)

    # Root logger
    root_logger = logging.getLogger()
    root_logger.setLevel(log_level)

    # Remove existing handlers
    root_logger.handlers.clear()

    # Handler: stdout (for Docker capture)
    handler = logging.StreamHandler(sys.stdout)
    handler.setLevel(log_level)

    if log_format == "json":
        formatter = JsonFormatter()
    else:
        formatter = logging.Formatter(
            "%(asctime)s %(levelname)s %(name)s %(message)s",
            datefmt="%Y-%m-%dT%H:%M:%S%z",
        )

    handler.setFormatter(formatter)
    root_logger.addHandler(handler)

    # Handler: file rotation (for persistence)
    file_handler = logging.handlers.RotatingFileHandler(
        filename="/logs/videodetect.log",
        maxBytes=rotation_max_bytes,
        backupCount=rotation_backup_count,
        encoding="utf-8",
    )
    file_handler.setLevel(log_level)
    file_handler.setFormatter(formatter)
    root_logger.addHandler(file_handler)

    logging.info("Logging configured: level=%s format=%s", level, log_format)


class JsonFormatter(logging.Formatter):
    """JSON log formatter with standardized fields."""

    def format(self, record: logging.LogRecord) -> str:
        log_data = {
            "timestamp": datetime.fromtimestamp(record.created, tz=timezone.utc).isoformat(),
            "level": record.levelname,
            "logger": record.name,
            "message": record.getMessage(),
            "module": record.module,
            "function": record.funcName,
            "line": record.lineno,
        }

        # Add extra fields
        if hasattr(record, "video_id"):
            log_data["video_id"] = record.video_id
        if hasattr(record, "metadata"):
            log_data["metadata"] = record.metadata

        # Add exception info if present
        if record.exc_info and record.exc_info[0] is not None:
            log_data["exception"] = self.formatException(record.exc_info)

        return json.dumps(log_data, default=str)