from pathlib import Path
from typing import Dict

from langchain_core.tools import tool
from rich.panel import Panel

from ra_aid.console import console
from ra_aid.console.formatting import print_error


def truncate_display_str(s: str, max_length: int = 30) -> str:
    """Truncate a string for display purposes if it exceeds max length.

    Args:
        s: String to truncate
        max_length: Maximum length before truncating

    Returns:
        Truncated string with ellipsis if needed
    """
    if len(s) <= max_length:
        return s
    return s[:max_length] + "..."


def format_string_for_display(s: str, threshold: int = 30) -> str:
    """Format a string for display, showing either quoted string or length.

    Args:
        s: String to format
        threshold: Max length before switching to character count display

    Returns:
        Formatted string for display
    """
    if len(s) <= threshold:
        return f"'{s}'"
    return f"[{len(s)} characters]"


@tool
def file_str_replace(filepath: str, old_str: str, new_str: str, *, replace_all: bool = False) -> Dict[str, any]:
    """Replace an exact string match in a file with a new string.
    Only performs replacement if the old string appears exactly once, or replace_all is True.

    Args:
        filepath: Path to the file to modify
        old_str: Exact string to replace
        new_str: String to replace with
        replace_all: If True, replace all occurrences of the string (default: False)
    """
    try:
        path = Path(filepath)
        if not path.exists():
            msg = f"File not found: {filepath}"
            print_error(msg)
            return {"success": False, "message": msg}

        content = path.read_text()
        count = content.count(old_str)

        if count == 0:
            msg = f"String not found: {truncate_display_str(old_str)}"
            print_error(msg)
            return {"success": False, "message": msg}
        elif count > 1 and not replace_all:
            msg = f"String appears {count} times - must be unique (use replace_all=True to replace all occurrences)"
            print_error(msg)
            return {"success": False, "message": msg}

        new_content = content.replace(old_str, new_str)
        path.write_text(new_content)

        replacement_msg = f"Replaced in {filepath}:"
        if count > 1 and replace_all:
            replacement_msg = f"Replaced {count} occurrences in {filepath}:"
            
        console.print(
            Panel(
                f"{replacement_msg}\n{format_string_for_display(old_str)} → {format_string_for_display(new_str)}",
                title="✓ String Replaced",
                border_style="bright_blue",
            )
        )
        
        success_msg = f"Successfully replaced '{old_str}' with '{new_str}' in {filepath}"
        if count > 1 and replace_all:
            success_msg = f"Successfully replaced {count} occurrences of '{old_str}' with '{new_str}' in {filepath}"
            
        return {
            "success": True,
            "message": success_msg,
        }

    except Exception as e:
        msg = f"Error: {str(e)}"
        print_error(msg)
        return {"success": False, "message": msg}