"""
Trilium notes executor for searching and creating notes via ETAPI.

This module provides integration with Trilium notes through the ETAPI HTTP API
with improved resilience: timeout configuration, retry logic, and connection pooling.
"""

import os
import asyncio
import aiohttp
from typing import Dict, Optional
from ..utils.resilience import async_retry


TRILIUM_URL = os.getenv("TRILIUM_URL", "http://localhost:8080")
TRILIUM_TOKEN = os.getenv("TRILIUM_ETAPI_TOKEN", "")

# Module-level session for connection pooling
_session: Optional[aiohttp.ClientSession] = None


def get_session() -> aiohttp.ClientSession:
    """Get or create shared aiohttp session for connection pooling."""
    global _session
    if _session is None or _session.closed:
        timeout = aiohttp.ClientTimeout(
            total=float(os.getenv("TRILIUM_TIMEOUT", "30.0")),
            connect=float(os.getenv("TRILIUM_CONNECT_TIMEOUT", "10.0"))
        )
        _session = aiohttp.ClientSession(timeout=timeout)
    return _session


@async_retry(
    max_attempts=3,
    exceptions=(aiohttp.ClientError, asyncio.TimeoutError)
)
async def search_notes(args: Dict) -> Dict:
    """Search Trilium notes via ETAPI with retry logic.

    Args:
        args: Dictionary containing:
            - query (str): Search query
            - limit (int, optional): Maximum notes to return (default: 5, max: 20)

    Returns:
        dict: Search results containing:
            - notes (list): List of notes with noteId, title, content, type
            - count (int): Number of notes returned
            OR
            - error (str): Error message if search failed
    """
    query = args.get("query")
    limit = args.get("limit", 5)

    # Validation
    if not query:
        return {"error": "No query provided"}

    if not TRILIUM_TOKEN:
        return {
            "error": "TRILIUM_ETAPI_TOKEN not configured in environment",
            "hint": "Set TRILIUM_ETAPI_TOKEN in .env file"
        }

    # Cap limit
    limit = min(max(limit, 1), 20)

    try:
        session = get_session()
        async with session.get(
            f"{TRILIUM_URL}/etapi/notes",
            params={"search": query, "limit": limit},
            headers={"Authorization": TRILIUM_TOKEN}
        ) as resp:
            if resp.status == 200:
                data = await resp.json()
                # ETAPI returns {"results": [...]} format
                results = data.get("results", [])
                return {
                    "notes": results,
                    "count": len(results)
                }
            elif resp.status == 401:
                return {
                    "error": "Authentication failed. Check TRILIUM_ETAPI_TOKEN",
                    "status": 401
                }
            elif resp.status == 404:
                return {
                    "error": "Trilium API endpoint not found. Check TRILIUM_URL",
                    "status": 404,
                    "url": TRILIUM_URL
                }
            else:
                error_text = await resp.text()
                return {
                    "error": f"HTTP {resp.status}: {error_text}",
                    "status": resp.status
                }

    except aiohttp.ClientConnectorError as e:
        return {
            "error": f"Cannot connect to Trilium at {TRILIUM_URL}",
            "hint": "Check if Trilium is running and URL is correct",
            "details": str(e)
        }
    except asyncio.TimeoutError:
        timeout = os.getenv("TRILIUM_TIMEOUT", "30.0")
        return {
            "error": f"Trilium request timeout after {timeout}s",
            "hint": "Trilium may be slow or unresponsive"
        }
    except Exception as e:
        return {
            "error": f"Search failed: {str(e)}",
            "type": type(e).__name__
        }


@async_retry(
    max_attempts=3,
    exceptions=(aiohttp.ClientError, asyncio.TimeoutError)
)
async def create_note(args: Dict) -> Dict:
    """Create a note in Trilium via ETAPI with retry logic.

    Args:
        args: Dictionary containing:
            - title (str): Note title
            - content (str): Note content in markdown or HTML
            - parent_note_id (str, optional): Parent note ID to nest under

    Returns:
        dict: Creation result containing:
            - noteId (str): ID of created note
            - title (str): Title of created note
            - success (bool): True if created successfully
            OR
            - error (str): Error message if creation failed
    """
    title = args.get("title")
    content = args.get("content")
    parent_note_id = args.get("parent_note_id", "root")  # Default to root if not specified

    # Validation
    if not title:
        return {"error": "No title provided"}

    if not content:
        return {"error": "No content provided"}

    if not TRILIUM_TOKEN:
        return {
            "error": "TRILIUM_ETAPI_TOKEN not configured in environment",
            "hint": "Set TRILIUM_ETAPI_TOKEN in .env file"
        }

    # Prepare payload
    payload = {
        "parentNoteId": parent_note_id,  # Always include parentNoteId
        "title": title,
        "content": content,
        "type": "text",
        "mime": "text/html"
    }

    try:
        session = get_session()
        async with session.post(
            f"{TRILIUM_URL}/etapi/create-note",
            json=payload,
            headers={"Authorization": TRILIUM_TOKEN}
        ) as resp:
            if resp.status in [200, 201]:
                data = await resp.json()
                return {
                    "noteId": data.get("noteId"),
                    "title": title,
                    "success": True
                }
            elif resp.status == 401:
                return {
                    "error": "Authentication failed. Check TRILIUM_ETAPI_TOKEN",
                    "status": 401
                }
            elif resp.status == 404:
                return {
                    "error": "Trilium API endpoint not found. Check TRILIUM_URL",
                    "status": 404,
                    "url": TRILIUM_URL
                }
            else:
                error_text = await resp.text()
                return {
                    "error": f"HTTP {resp.status}: {error_text}",
                    "status": resp.status
                }

    except aiohttp.ClientConnectorError as e:
        return {
            "error": f"Cannot connect to Trilium at {TRILIUM_URL}",
            "hint": "Check if Trilium is running and URL is correct",
            "details": str(e)
        }
    except asyncio.TimeoutError:
        timeout = os.getenv("TRILIUM_TIMEOUT", "30.0")
        return {
            "error": f"Trilium request timeout after {timeout}s",
            "hint": "Trilium may be slow or unresponsive"
        }
    except Exception as e:
        return {
            "error": f"Note creation failed: {str(e)}",
            "type": type(e).__name__
        }