"""JSON format converter."""

import json
from pathlib import Path
from typing import Any, Dict, Union

from config_converter.converters.base import BaseConverter, ConversionError


class JsonConverter(BaseConverter):
    """Converter for JSON configuration files."""

    FORMAT_NAME = "json"
    FILE_EXTENSIONS = ["json"]

    def read(self, source: Union[str, Path]) -> Dict[str, Any]:
        """Read and parse a JSON configuration file."""
        try:
            with open(source, "r", encoding="utf-8") as f:
                data = json.load(f)
                return data if data is not None else {}
        except json.JSONDecodeError as e:
            raise ConversionError(f"Invalid JSON in {source}: {e}") from e
        except FileNotFoundError as e:
            raise ConversionError(f"File not found: {source}") from e
        except PermissionError as e:
            raise ConversionError(f"Permission denied: {source}") from e

    def write(self, data: Dict[str, Any], target: Union[str, Path]) -> None:
        """Write configuration data to a JSON file."""
        try:
            with open(target, "w", encoding="utf-8") as f:
                json.dump(data, f, indent=2, ensure_ascii=False)
        except (OSError, TypeError) as e:
            raise ConversionError(f"Failed to write JSON to {target}: {e}") from e

    def parse(self, content: str) -> Dict[str, Any]:
        """Parse JSON content from a string."""
        try:
            data = json.loads(content)
            return data if data is not None else {}
        except json.JSONDecodeError as e:
            raise ConversionError(f"Invalid JSON content: {e}") from e

    def format(self, data: Dict[str, Any]) -> str:
        """Format configuration data to a JSON string."""
        try:
            return json.dumps(data, indent=2, ensure_ascii=False)
        except (TypeError, ValueError) as e:
            raise ConversionError(f"Failed to format data as JSON: {e}") from e