import { useState, useEffect } from "react";

interface StepData {
  id: string;
  status: "pending" | "active" | "completed" | "error";
  detail?: string;
  timestamp?: string;
}

interface StatusResponse {
  current_step: string | null;
  steps: StepData[];
  started_at: string | null;
  completed_at: string | null;
}

interface WorkflowStep {
  id: string;
  label: string;
  icon: JSX.Element;
  status: "pending" | "active" | "completed" | "error";
  detail?: string;
}

interface WorkflowStatusProps {
  sessionId?: string;
}

const STEP_CONFIG: { id: string; label: string; icon: JSX.Element; defaultDetail: string }[] = [
  {
    id: "fetch",
    label: "Fetch Responses",
    icon: (
      <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
        <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M4 16v1a3 3 0 003 3h10a3 3 0 003-3v-1m-4-4l-4 4m0 0l-4-4m4 4V4" />
      </svg>
    ),
    defaultDetail: "Getting data from Google Sheets",
  },
  {
    id: "normalize",
    label: "Parse Data",
    icon: (
      <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
        <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2" />
      </svg>
    ),
    defaultDetail: "Organizing questions and answers",
  },
  {
    id: "grade",
    label: "Grade Answers",
    icon: (
      <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
        <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 12l2 2 4-4m6 2a9 9 0 11-18 0 9 9 0 0118 0z" />
      </svg>
    ),
    defaultDetail: "Comparing with correct answers",
  },
  {
    id: "explain",
    label: "Generate Explanations",
    icon: (
      <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
        <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9.663 17h4.673M12 3v1m6.364 1.636l-.707.707M21 12h-1M4 12H3m3.343-5.657l-.707-.707m2.828 9.9a5 5 0 117.072 0l-.548.547A3.374 3.374 0 0014 18.469V19a2 2 0 11-4 0v-.531c0-.895-.356-1.754-.988-2.386l-.548-.547z" />
      </svg>
    ),
    defaultDetail: "Explaining wrong answers",
  },
  {
    id: "group",
    label: "Create Peer Groups",
    icon: (
      <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
        <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M17 20h5v-2a3 3 0 00-5.356-1.857M17 20H7m10 0v-2c0-.656-.126-1.283-.356-1.857M7 20H2v-2a3 3 0 015.356-1.857M7 20v-2c0-.656.126-1.283.356-1.857m0 0a5.002 5.002 0 019.288 0M15 7a3 3 0 11-6 0 3 3 0 016 0z" />
      </svg>
    ),
    defaultDetail: "Matching helpers with learners",
  },
  {
    id: "report",
    label: "Generate Report",
    icon: (
      <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
        <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 17v-2m3 2v-4m3 4v-6m2 10H7a2 2 0 01-2-2V5a2 2 0 012-2h5.586a1 1 0 01.707.293l5.414 5.414a1 1 0 01.293.707V19a2 2 0 01-2 2z" />
      </svg>
    ),
    defaultDetail: "Creating comprehensive report",
  },
  {
    id: "email",
    label: "Send Email",
    icon: (
      <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
        <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M3 8l7.89 5.26a2 2 0 002.22 0L21 8M5 19h14a2 2 0 002-2V7a2 2 0 00-2-2H5a2 2 0 00-2 2v10a2 2 0 002 2z" />
      </svg>
    ),
    defaultDetail: "Delivering report to inbox",
  },
];

export function WorkflowStatus({ sessionId = "default" }: WorkflowStatusProps) {
  const [steps, setSteps] = useState<WorkflowStep[]>(
    STEP_CONFIG.map(s => ({ ...s, status: "pending" as const, detail: s.defaultDetail }))
  );
  const [isConnected, setIsConnected] = useState(false);
  const [isAnalyzing, setIsAnalyzing] = useState(false);

  useEffect(() => {
    let eventSource: EventSource | null = null;
    let retryCount = 0;
    const maxRetries = 3;

    const connect = () => {
      eventSource = new EventSource(`/api/status/${sessionId}/stream`);

      eventSource.onopen = () => {
        setIsConnected(true);
        retryCount = 0;
      };

      eventSource.onmessage = (event) => {
        try {
          const data: StatusResponse = JSON.parse(event.data);
          
          // Check if there's any activity
          const hasActivity = data.steps && data.steps.length > 0;
          setIsAnalyzing(hasActivity && !data.completed_at);
          
          // Update steps based on server data
          setSteps(prevSteps => {
            return prevSteps.map(step => {
              const serverStep = data.steps?.find(s => s.id === step.id);
              if (serverStep) {
                return {
                  ...step,
                  status: serverStep.status as WorkflowStep["status"],
                  detail: serverStep.detail || step.detail,
                };
              }
              return step;
            });
          });
        } catch (e) {
          console.error("Error parsing status:", e);
        }
      };

      eventSource.onerror = () => {
        setIsConnected(false);
        eventSource?.close();
        
        // Retry connection
        if (retryCount < maxRetries) {
          retryCount++;
          setTimeout(connect, 2000 * retryCount);
        }
      };
    };

    connect();

    return () => {
      eventSource?.close();
    };
  }, [sessionId]);

  const getStatusColor = (status: WorkflowStep["status"]) => {
    switch (status) {
      case "completed": return "bg-[var(--color-success)] text-white";
      case "active": return "bg-[var(--color-accent)] text-white animate-pulse";
      case "error": return "bg-red-500 text-white";
      default: return "bg-[var(--color-border)] text-[var(--color-text-muted)]";
    }
  };

  const getLineColor = (status: WorkflowStep["status"]) => {
    switch (status) {
      case "completed": return "bg-[var(--color-success)]";
      case "active": return "bg-[var(--color-accent)]";
      default: return "bg-[var(--color-border)]";
    }
  };

  const activeStep = steps.find(s => s.status === "active");
  const completedCount = steps.filter(s => s.status === "completed").length;

  return (
    <div className="card p-4">
      {/* Header */}
      <div className="flex items-center justify-between mb-4">
        <div className="flex items-center gap-2">
          <div className={`w-2 h-2 rounded-full ${isAnalyzing ? 'bg-[var(--color-accent)] animate-pulse' : isConnected ? 'bg-[var(--color-success)]' : 'bg-[var(--color-border)]'}`} />
          <h3 className="font-display text-sm font-semibold text-[var(--color-text)]">
            {isAnalyzing ? "AI Agent Working..." : "Agent Status"}
          </h3>
        </div>
        {completedCount > 0 && (
          <span className="text-xs text-[var(--color-text-muted)]">
            {completedCount}/{steps.length}
          </span>
        )}
      </div>

      {/* Active step highlight */}
      {activeStep && (
        <div className="mb-4 p-3 rounded-lg bg-[var(--color-accent)]/10 border border-[var(--color-accent)]/20">
          <div className="flex items-center gap-2">
            <div className="w-5 h-5 rounded-full bg-[var(--color-accent)] flex items-center justify-center animate-pulse">
              <div className="w-2 h-2 bg-white rounded-full" />
            </div>
            <div>
              <div className="text-sm font-medium text-[var(--color-accent)]">
                {activeStep.label}
              </div>
              <div className="text-xs text-[var(--color-text-muted)]">
                {activeStep.detail}
              </div>
            </div>
          </div>
        </div>
      )}
      
      {/* Steps list */}
      <div className="space-y-1">
        {steps.map((step, index) => (
          <div key={step.id} className="relative">
            {/* Connector line */}
            {index < steps.length - 1 && (
              <div 
                className={`absolute left-[11px] top-[24px] w-0.5 h-4 transition-colors duration-300 ${getLineColor(step.status)}`}
              />
            )}
            
            <div className="flex items-center gap-3 py-1">
              {/* Icon circle */}
              <div 
                className={`flex-shrink-0 w-6 h-6 rounded-full flex items-center justify-center transition-all duration-300 ${getStatusColor(step.status)}`}
              >
                {step.status === "completed" ? (
                  <svg className="w-3 h-3" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={3} d="M5 13l4 4L19 7" />
                  </svg>
                ) : step.status === "active" ? (
                  <div className="w-2 h-2 bg-white rounded-full" />
                ) : step.status === "error" ? (
                  <svg className="w-3 h-3" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={3} d="M6 18L18 6M6 6l12 12" />
                  </svg>
                ) : (
                  <span className="text-[10px]">{index + 1}</span>
                )}
              </div>
              
              {/* Label */}
              <div className={`text-sm transition-colors ${
                step.status === "active" 
                  ? "font-medium text-[var(--color-accent)]" 
                  : step.status === "completed"
                  ? "text-[var(--color-success)]"
                  : step.status === "error"
                  ? "text-red-500"
                  : "text-[var(--color-text-muted)]"
              }`}>
                {step.label}
              </div>
            </div>
          </div>
        ))}
      </div>

      {/* Connection status */}
      <div className="mt-4 pt-3 border-t border-[var(--color-border)]">
        <div className="flex items-center gap-2 text-xs text-[var(--color-text-muted)]">
          <div className={`w-1.5 h-1.5 rounded-full ${isConnected ? 'bg-green-500' : 'bg-gray-400'}`} />
          {isConnected ? "Live updates" : "Connecting..."}
        </div>
      </div>
    </div>
  );
}