import { useQuery, useQueryClient } from '@tanstack/react-query'
import { listProjects } from '../services/api'
import { AlertCircle, RefreshCw, FolderKanban, Users } from 'lucide-react'

const STATUS_COLORS: Record<string, string> = {
  planned: 'bg-purple-500',
  active: 'bg-green-500',
  paused: 'bg-yellow-500',
  completed: 'bg-blue-400',
}

export default function ProjectsPage() {
  const queryClient = useQueryClient()

  const { data, isLoading, error } = useQuery({
    queryKey: ['projects'],
    queryFn: listProjects,
  })

  const projects = data?.data ?? []

  if (isLoading) return <ProjectsSkeleton />

  if (error) {
    return (
      <div className="flex flex-col items-center justify-center h-96 gap-4">
        <AlertCircle size={48} className="text-danger" />
        <p className="text-danger text-lg">Failed to load projects</p>
        <button
          onClick={() => queryClient.invalidateQueries({ queryKey: ['projects'] })}
          className="flex items-center gap-2 px-4 py-2 rounded-lg bg-primary/10 text-primary hover:bg-primary/20 transition-colors"
        >
          <RefreshCw size={16} /> Retry
        </button>
      </div>
    )
  }

  return (
    <div className="space-y-6">
      <header>
        <h1 className="text-2xl font-bold">Projects</h1>
        <p className="text-on-surface-variant">Tracked projects and initiatives</p>
      </header>

      {projects.length === 0 ? (
        <div className="flex flex-col items-center justify-center h-48 gap-3 border border-dashed border-surface-light rounded-xl">
          <FolderKanban size={40} className="text-on-surface-muted" />
          <p className="text-on-surface-muted text-lg">No projects tracked</p>
          <p className="text-on-surface-muted text-sm">Projects synced from Linear will appear here.</p>
        </div>
      ) : (
        <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 gap-4">
          {projects.map((project) => (
            <div
              key={project.id}
              className="p-5 rounded-xl border border-surface-light bg-surface-dark hover:border-surface-lighter transition-colors flex flex-col"
            >
              <div className="flex items-start justify-between mb-3">
                <FolderKanban size={20} className="text-on-surface-variant shrink-0 mt-0.5" />
                <ProjectStatusBadge status={project.status} />
              </div>

              <h3 className="font-semibold mb-1">{project.name}</h3>
              {project.description && (
                <p className="text-sm text-on-surface-variant mb-4 line-clamp-2 flex-1">
                  {project.description}
                </p>
              )}

              <div className="flex items-center gap-2 text-xs text-on-surface-muted pt-3 border-t border-surface-light">
                <Users size={14} />
                <span>{project.agentIds?.length ?? 0} agent{(project.agentIds?.length ?? 0) !== 1 ? 's' : ''} assigned</span>
              </div>
            </div>
          ))}
        </div>
      )}
    </div>
  )
}

function ProjectStatusBadge({ status }: { status: string }) {
  return (
    <div className="flex items-center gap-1.5 px-2 py-1 rounded-full bg-surface-light/50">
      <div className={`w-2 h-2 rounded-full ${STATUS_COLORS[status] ?? 'bg-gray-500'}`} />
      <span className="text-xs capitalize text-on-surface-variant">{status}</span>
    </div>
  )
}

function ProjectsSkeleton() {
  return (
    <div className="space-y-6 animate-pulse">
      <div>
        <div className="h-8 w-40 skeleton mb-2" />
        <div className="h-4 w-56 skeleton" />
      </div>
      <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 gap-4">
        {[...Array(6)].map((_, i) => (
          <div key={i} className="p-5 rounded-xl border border-surface-light bg-surface-dark">
            <div className="flex justify-between mb-3">
              <div className="h-5 w-5 rounded skeleton" />
              <div className="h-6 w-20 rounded-full skeleton" />
            </div>
            <div className="h-5 w-3/4 skeleton mb-2" />
            <div className="h-4 w-full skeleton mb-2" />
            <div className="h-4 w-2/3 skeleton mb-4" />
            <div className="pt-3 border-t border-surface-light">
              <div className="h-3 w-32 skeleton" />
            </div>
          </div>
        ))}
      </div>
    </div>
  )
}