from mcp.server.fastmcp import FastMCP
import requests
from typing import Optional, List, Union
import re

mcp = FastMCP("Notifications")

@mcp.tool()
def send_notification(
    topic: str,
    message: str,
    title: Optional[str] = None,
    priority: str = "urgent",
    tags: Optional[Union[List[str], str]] = None,
    click_url: Optional[str] = None,
    attach_url: Optional[str] = None,
    delay: Optional[str] = None
):
    """Send notification via ntfy.sh.
    
    Args:
        topic: Topic name (letters, numbers, dashes, underscores only)
        message: Message body (supports markdown)
        title: Optional title
        priority: "min", "low", "default", "high", "urgent" 
        tags: Emoji shortcodes as list or comma-separated (e.g. "warning,fire" or ["bell","calendar"])
        click_url: URL to open on click
        attach_url: Image/file URL to attach
        delay: Delay like "10s", "5m", "2h"
    
    """
    # Validate topic name
    if not re.match(r'^[a-zA-Z0-9_-]+$', topic):
        return "❌ Invalid topic: use only letters, numbers, dashes, underscores"
    
    url = f"https://ntfy.sh/{topic}"
    
    headers = {"Content-Type": "text/plain; charset=utf-8"}
    
    if title:
        headers["Title"] = title
    
    if priority:
        if priority not in ["min", "low", "default", "high", "urgent"]:
            return f"❌ Invalid priority: {priority}"
        headers["Priority"] = priority
    
    if tags:
        # Handle both string and list inputs
        if isinstance(tags, str):
            tags = [t.strip() for t in tags.split(",")]
        headers["Tags"] = ",".join(tags)
    
    if click_url:
        headers["Click"] = click_url
    
    if attach_url:
        headers["Attach"] = attach_url
    
    if delay:
        headers["Delay"] = delay
    
    try:
        response = requests.post(url, data=message.encode('utf-8'), headers=headers, timeout=10)
        response.raise_for_status()
        
        result = f"✅ Sent to '{topic}'"
        if delay:
            result += f" (delayed by {delay})"
        return result
        
    except requests.exceptions.HTTPError as e:
        status = e.response.status_code
        if status == 400:
            return "❌ Bad request: check message format"
        elif status == 429:
            return "❌ Rate limited: too many requests"
        elif status == 507:
            return "❌ Storage full: message too large"
        return f"❌ HTTP error: {status}"
    except Exception as e:
        return f"❌ Error: {str(e)}"

if __name__ == "__main__":
    mcp.run()