"""
HTTP client for communicating with remote Intercept agents.
"""

from __future__ import annotations

import logging
from typing import Any

import requests

logger = logging.getLogger('intercept.agent_client')


class AgentHTTPError(RuntimeError):
    """Exception raised when agent HTTP request fails."""

    def __init__(self, message: str, status_code: int | None = None):
        super().__init__(message)
        self.status_code = status_code


class AgentConnectionError(AgentHTTPError):
    """Exception raised when agent is unreachable."""
    pass


class AgentClient:
    """HTTP client for communicating with a remote Intercept agent."""

    def __init__(
        self,
        base_url: str,
        api_key: str | None = None,
        timeout: float = 60.0
    ):
        """
        Initialize agent client.

        Args:
            base_url: Base URL of the agent (e.g., http://192.168.1.50:8020)
            api_key: Optional API key for authentication
            timeout: Request timeout in seconds
        """
        self.base_url = base_url.rstrip('/')
        self.api_key = api_key
        self.timeout = timeout

    def _headers(self) -> dict:
        """Get request headers."""
        headers = {'Content-Type': 'application/json'}
        if self.api_key:
            headers['X-API-Key'] = self.api_key
        return headers

    def _get(self, path: str, params: dict | None = None) -> dict:
        """
        Perform GET request to agent.

        Args:
            path: URL path (e.g., /capabilities)
            params: Optional query parameters

        Returns:
            Parsed JSON response

        Raises:
            AgentHTTPError: On HTTP errors
            AgentConnectionError: If agent is unreachable
        """
        url = f"{self.base_url}{path}"
        try:
            response = requests.get(
                url,
                headers=self._headers(),
                params=params,
                timeout=self.timeout
            )
            response.raise_for_status()
            return response.json() if response.content else {}
        except requests.ConnectionError as e:
            raise AgentConnectionError(f"Cannot connect to agent at {self.base_url}: {e}")
        except requests.Timeout:
            raise AgentConnectionError(f"Request to agent timed out after {self.timeout}s")
        except requests.HTTPError as e:
            # Try to extract error message from response body
            error_msg = f"Agent returned error: {e.response.status_code}"
            try:
                error_data = e.response.json()
                if 'message' in error_data:
                    error_msg = error_data['message']
                elif 'error' in error_data:
                    error_msg = error_data['error']
            except Exception:
                pass
            raise AgentHTTPError(error_msg, status_code=e.response.status_code)
        except requests.RequestException as e:
            raise AgentHTTPError(f"Request failed: {e}")

    def _post(self, path: str, data: dict | None = None) -> dict:
        """
        Perform POST request to agent.

        Args:
            path: URL path (e.g., /sensor/start)
            data: Optional JSON body

        Returns:
            Parsed JSON response

        Raises:
            AgentHTTPError: On HTTP errors
            AgentConnectionError: If agent is unreachable
        """
        url = f"{self.base_url}{path}"
        try:
            response = requests.post(
                url,
                json=data or {},
                headers=self._headers(),
                timeout=self.timeout
            )
            response.raise_for_status()
            return response.json() if response.content else {}
        except requests.ConnectionError as e:
            raise AgentConnectionError(f"Cannot connect to agent at {self.base_url}: {e}")
        except requests.Timeout:
            raise AgentConnectionError(f"Request to agent timed out after {self.timeout}s")
        except requests.HTTPError as e:
            # Try to extract error message from response body
            error_msg = f"Agent returned error: {e.response.status_code}"
            try:
                error_data = e.response.json()
                if 'message' in error_data:
                    error_msg = error_data['message']
                elif 'error' in error_data:
                    error_msg = error_data['error']
            except Exception:
                pass
            raise AgentHTTPError(error_msg, status_code=e.response.status_code)
        except requests.RequestException as e:
            raise AgentHTTPError(f"Request failed: {e}")

    def post(self, path: str, data: dict | None = None) -> dict:
        """Public POST method for arbitrary endpoints."""
        return self._post(path, data)

    # =========================================================================
    # Capability & Status
    # =========================================================================

    def get_capabilities(self) -> dict:
        """
        Get agent capabilities (available modes, devices).

        Returns:
            Dict with 'modes' (mode -> bool), 'devices' (list), 'agent_version'
        """
        return self._get('/capabilities')

    def get_status(self) -> dict:
        """
        Get agent status.

        Returns:
            Dict with 'running_modes', 'uptime', 'push_enabled', etc.
        """
        return self._get('/status')

    def health_check(self) -> bool:
        """
        Check if agent is healthy.

        Returns:
            True if agent is reachable and healthy
        """
        try:
            result = self._get('/health')
            return result.get('status') == 'healthy'
        except (AgentHTTPError, AgentConnectionError):
            return False

    def get_config(self) -> dict:
        """Get agent configuration (non-sensitive fields)."""
        return self._get('/config')

    def update_config(self, **kwargs) -> dict:
        """
        Update agent configuration.

        Args:
            push_enabled: Enable/disable push mode
            push_interval: Push interval in seconds

        Returns:
            Updated config
        """
        return self._post('/config', kwargs)

    # =========================================================================
    # Mode Operations
    # =========================================================================

    def start_mode(self, mode: str, params: dict | None = None) -> dict:
        """
        Start a mode on the agent.

        Args:
            mode: Mode name (e.g., 'sensor', 'adsb', 'wifi')
            params: Mode-specific parameters

        Returns:
            Start result with 'status' field
        """
        return self._post(f'/{mode}/start', params or {})

    def stop_mode(self, mode: str) -> dict:
        """
        Stop a running mode on the agent.

        Args:
            mode: Mode name

        Returns:
            Stop result with 'status' field
        """
        return self._post(f'/{mode}/stop')

    def get_mode_status(self, mode: str) -> dict:
        """
        Get status of a specific mode.

        Args:
            mode: Mode name

        Returns:
            Mode status with 'running' field
        """
        return self._get(f'/{mode}/status')

    def get_mode_data(self, mode: str) -> dict:
        """
        Get current data snapshot for a mode.

        Args:
            mode: Mode name

        Returns:
            Data snapshot with 'data' field
        """
        return self._get(f'/{mode}/data')

    # =========================================================================
    # Convenience Methods
    # =========================================================================

    def refresh_metadata(self) -> dict:
        """
        Fetch comprehensive metadata from agent.

        Returns:
            Dict with capabilities, status, and config
        """
        metadata = {
            'capabilities': None,
            'status': None,
            'config': None,
            'healthy': False,
        }

        try:
            metadata['capabilities'] = self.get_capabilities()
            metadata['status'] = self.get_status()
            metadata['config'] = self.get_config()
            metadata['healthy'] = True
        except (AgentHTTPError, AgentConnectionError) as e:
            logger.warning(f"Failed to refresh agent metadata: {e}")

        return metadata

    def __repr__(self) -> str:
        return f"AgentClient({self.base_url})"


def create_client_from_agent(agent: dict) -> AgentClient:
    """
    Create an AgentClient from an agent database record.

    Args:
        agent: Agent dict from database

    Returns:
        Configured AgentClient
    """
    return AgentClient(
        base_url=agent['base_url'],
        api_key=agent.get('api_key'),
        timeout=60.0
    )