import { useEffect, useState } from 'react'
import { Link } from 'react-router-dom'

type Container = { id: string; name: string; status: string }

function isContainerResponse(value: unknown): value is { containers: Container[] } {
  if (!value || typeof value !== 'object') return false
  const containers = (value as Record<string, unknown>).containers
  return Array.isArray(containers) && containers.every((container: unknown) => {
    if (!container || typeof container !== 'object') return false
    const item = container as Record<string, unknown>
    return typeof item.id === 'string' && typeof item.name === 'string' && typeof item.status === 'string'
  })
}

export default function NodeDockerContainers({ nodeId, clusterId, detailed = false }: {
  nodeId: string; clusterId: string; detailed?: boolean
}) {
  const [containers, setContainers] = useState<Container[] | null>(null)
  const [status, setStatus] = useState('Connecting…')
  const [attempt, setAttempt] = useState(0)

  useEffect(() => {
    let active = true
    const controller = new AbortController()
    let socket: WebSocket | undefined
    const disconnected = () => {
      if (!active) return
      setContainers(null)
      setStatus('Docker feed disconnected. Reconnect to try again.')
    }
    const connect = async () => {
      setContainers(null)
      setStatus('Loading node details…')
      try {
        const apiBaseUrl = import.meta.env.VITE_API_BASE_URL
        if (!apiBaseUrl) throw new Error('API URL is not configured.')
        const token = localStorage.getItem('access_token')
        const response = await fetch(
          `${apiBaseUrl.replace(/\/$/, '')}/spock/node-interfaces/${encodeURIComponent(nodeId)}`,
          {
            headers: token ? { Authorization: `Bearer ${token}` } : {},
            signal: controller.signal,
          },
        )
        if (!response.ok) throw new Error('Failed to load node details.')
        const result = await response.json()
        const node = result?.node
        if (result?.status !== 'success' || node?.uuid !== nodeId
          || typeof node.host !== 'string' || !node.host.trim()) {
          throw new Error('Invalid node host received.')
        }
        if (!active) return
        const host = node.host.trim()
        const hostname = host.includes(':') && !host.startsWith('[') ? `[${host}]` : host
        setStatus('Connecting…')
        socket = new WebSocket(`ws://${hostname}:9100/ws/docker/containers`)
        socket.onopen = () => {
          if (active) setStatus('Waiting for containers…')
        }
        socket.onmessage = (event) => {
          if (!active) return
          try {
            const message: unknown = JSON.parse(event.data)
            if (!isContainerResponse(message)) throw new Error('Invalid container data')
            setContainers(message.containers)
            setStatus('Live')
          } catch {
            setContainers(null)
            setStatus('Invalid container data received.')
          }
        }
        socket.onerror = disconnected
        socket.onclose = disconnected
      } catch (error) {
        if (!active) return
        setStatus(error instanceof Error ? error.message : 'Unable to connect to the Docker feed.')
      }
    }
    void connect()
    return () => {
      active = false
      controller.abort()
      socket?.close()
    }
  }, [attempt, nodeId])

  const nodePath = `/clusters/${encodeURIComponent(clusterId)}/nodes/${encodeURIComponent(nodeId)}`
  const visibleContainers = detailed ? containers : containers?.slice(0, 3)

  return (
    <section className="node-docker-panel database-connections" aria-labelledby="docker-containers-heading">
      <div className="page-header">
        <h2 id="docker-containers-heading">Docker containers</h2>
        <div className="page-actions">
          {detailed && <Link className="secondary-button" to={nodePath}>Back to node</Link>}
          <p role="status">{status}</p>
          <button type="button" className="secondary-button" onClick={() => {
            setContainers(null)
            setStatus('Connecting…')
            setAttempt((current) => current + 1)
          }}>Reconnect</button>
        </div>
      </div>
      {containers !== null && (containers.length === 0 ? <p>No containers found.</p> : (
        <div className="nodes-table-wrap">
          <table className="nodes-table">
            <thead><tr><th scope="col">Name</th><th scope="col">Container ID</th><th scope="col">Status</th></tr></thead>
            <tbody>
              {visibleContainers?.map((container) => (
                <tr key={container.id}>
                  <td>{container.name}</td>
                  <td><code>{container.id}</code></td>
                  <td><span className={`connection-status${container.status === 'running' ? ' connected' : ''}`}>{container.status}</span></td>
                </tr>
              ))}
            </tbody>
          </table>
        </div>
      ))}
      {!detailed && containers && containers.length > 3 && (
        <p className="docker-view-all"><Link to={`${nodePath}/docker-containers`}>View all {containers.length} containers</Link></p>
      )}
    </section>
  )
}