/**
 * Agent Status Widget - shows running agents
 */

import { useState, useEffect } from "react";
import { Bot, Activity, AlertCircle, CheckCircle, Clock } from "lucide-react";
import type { WidgetProps } from "@mosaic/shared";

interface Agent {
  id: string;
  name: string;
  status: "IDLE" | "WORKING" | "WAITING" | "ERROR" | "TERMINATED";
  currentTask?: string;
  lastHeartbeat: string;
  taskCount: number;
}

export function AgentStatusWidget({ id: _id, config: _config }: WidgetProps) {
  const [agents, setAgents] = useState<Agent[]>([]);
  const [isLoading, setIsLoading] = useState(true);

  // Mock data for now - will fetch from API later
  useEffect(() => {
    setIsLoading(true);
    setTimeout(() => {
      setAgents([
        {
          id: "1",
          name: "Code Review Agent",
          status: "WORKING",
          currentTask: "Reviewing PR #123",
          lastHeartbeat: new Date().toISOString(),
          taskCount: 42,
        },
        {
          id: "2",
          name: "Documentation Agent",
          status: "IDLE",
          lastHeartbeat: new Date().toISOString(),
          taskCount: 15,
        },
        {
          id: "3",
          name: "Test Runner Agent",
          status: "ERROR",
          currentTask: "Failed to run tests",
          lastHeartbeat: new Date(Date.now() - 300000).toISOString(),
          taskCount: 28,
        },
      ]);
      setIsLoading(false);
    }, 500);
  }, []);

  const getStatusIcon = (status: Agent["status"]) => {
    switch (status) {
      case "WORKING":
        return <Activity className="w-4 h-4 text-blue-500 animate-pulse" />;
      case "IDLE":
        return <Clock className="w-4 h-4 text-gray-400" />;
      case "WAITING":
        return <Clock className="w-4 h-4 text-yellow-500" />;
      case "ERROR":
        return <AlertCircle className="w-4 h-4 text-red-500" />;
      case "TERMINATED":
        return <CheckCircle className="w-4 h-4 text-gray-500" />;
      default:
        return <Clock className="w-4 h-4 text-gray-400" />;
    }
  };

  const getStatusText = (status: Agent["status"]) => {
    return status.charAt(0).toUpperCase() + status.slice(1).toLowerCase();
  };

  const getTimeSinceLastHeartbeat = (timestamp: string) => {
    const now = new Date();
    const last = new Date(timestamp);
    const diffMs = now.getTime() - last.getTime();

    if (diffMs < 60000) return "Just now";
    if (diffMs < 3600000) return `${Math.floor(diffMs / 60000)}m ago`;
    if (diffMs < 86400000) return `${Math.floor(diffMs / 3600000)}h ago`;
    return `${Math.floor(diffMs / 86400000)}d ago`;
  };

  const stats = {
    total: agents.length,
    working: agents.filter((a) => a.status === "WORKING").length,
    idle: agents.filter((a) => a.status === "IDLE").length,
    error: agents.filter((a) => a.status === "ERROR").length,
  };

  if (isLoading) {
    return (
      <div className="flex items-center justify-center h-full">
        <div className="text-gray-500 text-sm">Loading agents...</div>
      </div>
    );
  }

  return (
    <div className="flex flex-col h-full space-y-3">
      {/* Summary stats */}
      <div className="grid grid-cols-4 gap-1 text-center text-xs">
        <div className="bg-gray-50 rounded p-2">
          <div className="text-lg font-bold text-gray-900">{stats.total}</div>
          <div className="text-gray-500">Total</div>
        </div>
        <div className="bg-blue-50 rounded p-2">
          <div className="text-lg font-bold text-blue-600">{stats.working}</div>
          <div className="text-blue-500">Working</div>
        </div>
        <div className="bg-gray-100 rounded p-2">
          <div className="text-lg font-bold text-gray-600">{stats.idle}</div>
          <div className="text-gray-500">Idle</div>
        </div>
        <div className="bg-red-50 rounded p-2">
          <div className="text-lg font-bold text-red-600">{stats.error}</div>
          <div className="text-red-500">Error</div>
        </div>
      </div>

      {/* Agent list */}
      <div className="flex-1 overflow-auto space-y-2">
        {agents.length === 0 ? (
          <div className="text-center text-gray-500 text-sm py-4">
            No agents configured
          </div>
        ) : (
          agents.map((agent) => (
            <div
              key={agent.id}
              className={`p-3 rounded-lg border ${
                agent.status === "ERROR"
                  ? "bg-red-50 border-red-200"
                  : agent.status === "WORKING"
                  ? "bg-blue-50 border-blue-200"
                  : "bg-gray-50 border-gray-200"
              }`}
            >
              <div className="flex items-center justify-between mb-2">
                <div className="flex items-center gap-2">
                  <Bot className="w-4 h-4 text-gray-600" />
                  <span className="text-sm font-medium text-gray-900">
                    {agent.name}
                  </span>
                </div>
                <div className="flex items-center gap-1 text-xs text-gray-500">
                  {getStatusIcon(agent.status)}
                  <span>{getStatusText(agent.status)}</span>
                </div>
              </div>

              {agent.currentTask && (
                <div className="text-xs text-gray-600 mb-1">{agent.currentTask}</div>
              )}

              <div className="flex items-center justify-between text-xs text-gray-400">
                <span>{agent.taskCount} tasks completed</span>
                <span>{getTimeSinceLastHeartbeat(agent.lastHeartbeat)}</span>
              </div>
            </div>
          ))
        )}
      </div>
    </div>
  );
}