import React from 'react';
import { GenerationStep } from '../types';
import { Database, Palette, FileText, Layers, Clapperboard, Check } from 'lucide-react';

interface PipelineVisualizerProps {
  currentStep: GenerationStep;
  onNavigate: (step: GenerationStep) => void;
  isProcessing: boolean;
}

const PipelineVisualizer: React.FC<PipelineVisualizerProps> = ({ currentStep, onNavigate, isProcessing }) => {
  
  const nodes = [
    { id: 'source', label: '來源選擇', icon: Database, steps: [GenerationStep.PROJECT_SELECTION], color: '#ec4899' },
    { id: 'style', label: '風格定義', icon: Palette, steps: [GenerationStep.STYLE_SELECTION], color: '#8b5cf6' },
    { id: 'blueprint', label: '結構藍圖', icon: FileText, steps: [GenerationStep.INPUT_PHASE, GenerationStep.STRUCTURE_PLANNING], color: '#6366f1' },
    { id: 'assets', label: '資產合成', icon: Layers, steps: [GenerationStep.ASSET_MANAGEMENT], color: '#06b6d4' },
    { id: 'prod', label: '分鏡製作', icon: Clapperboard, steps: [GenerationStep.PRODUCTION_DASHBOARD], color: '#10b981' },
  ];

  const getNodeStatus = (nodeSteps: GenerationStep[]) => {
    const stepOrder = Object.values(GenerationStep);
    const firstNodeStepIndex = stepOrder.indexOf(nodeSteps[0]);
    const currentStepIndex = stepOrder.indexOf(currentStep);

    if (nodeSteps.includes(currentStep)) return 'active';
    if (currentStepIndex > firstNodeStepIndex) return 'completed';
    return 'pending';
  };

  const getTargetStep = (nodeSteps: GenerationStep[]) => {
      return nodeSteps[0]; 
  }

  const nodeWidth = 40;
  const gap = 120;
  const startX = 50;
  const y = 40; // Centered vertically in the available space of Header (excluding text)

  return (
    <div className="w-full h-full flex items-center justify-center select-none">
        <div className="relative w-full max-w-3xl h-full">
            <svg className="w-full h-full overflow-visible">
                <defs>
                    <filter id="glow" x="-50%" y="-50%" width="200%" height="200%">
                        <feGaussianBlur stdDeviation="4" result="coloredBlur"/>
                        <feMerge>
                            <feMergeNode in="coloredBlur"/>
                            <feMergeNode in="SourceGraphic"/>
                        </feMerge>
                    </filter>
                </defs>

                {/* Edges */}
                {nodes.map((node, i) => {
                    if (i === nodes.length - 1) return null;
                    const status = getNodeStatus(node.steps);
                    const nextStatus = getNodeStatus(nodes[i+1].steps);
                    const isActiveFlow = status === 'active' && isProcessing;
                    const isCompletedFlow = nextStatus === 'active' || nextStatus === 'completed';

                    return (
                        <g key={`edge-${i}`}>
                            <line 
                                x1={startX + (i * gap) + nodeWidth/2} 
                                y1={y} 
                                x2={startX + ((i + 1) * gap) - nodeWidth/2} 
                                y2={y} 
                                stroke={isCompletedFlow ? "rgba(255,255,255,0.2)" : "rgba(255,255,255,0.05)"}
                                strokeWidth="2"
                            />
                            {(isActiveFlow || isCompletedFlow) && (
                                <line 
                                    x1={startX + (i * gap) + nodeWidth/2} 
                                    y1={y} 
                                    x2={startX + ((i + 1) * gap) - nodeWidth/2} 
                                    y2={y} 
                                    stroke={node.color}
                                    strokeWidth="2"
                                    strokeDasharray="4 4"
                                    className={isActiveFlow ? "animate-flow" : ""}
                                    opacity={isActiveFlow ? 1 : 0.5}
                                />
                            )}
                        </g>
                    );
                })}

                {/* Nodes */}
                {nodes.map((node, i) => {
                    const status = getNodeStatus(node.steps);
                    const cx = startX + (i * gap);
                    const isClickable = status === 'completed' || status === 'active';
                    
                    return (
                        <g 
                            key={node.id} 
                            onClick={() => isClickable && onNavigate(getTargetStep(node.steps))}
                            className={`transition-all duration-300 ${isClickable ? 'cursor-pointer hover:opacity-80' : 'opacity-40 cursor-not-allowed'}`}
                        >
                            {status === 'active' && (
                                <circle cx={cx} cy={y} r={nodeWidth / 1.5} fill={node.color} opacity="0.2" filter="url(#glow)" className="animate-pulse" />
                            )}
                            <circle 
                                cx={cx} 
                                cy={y} 
                                r={nodeWidth / 2} 
                                fill={status === 'active' ? node.color : (status === 'completed' ? '#1f2937' : '#000')}
                                stroke={status === 'active' ? '#fff' : (status === 'completed' ? node.color : '#374151')}
                                strokeWidth={status === 'active' ? 2 : 1}
                            />
                            <foreignObject x={cx - 10} y={y - 10} width="20" height="20">
                                <div className="flex items-center justify-center w-full h-full text-white">
                                    {status === 'completed' ? <Check className="w-4 h-4 text-emerald-400" /> : <node.icon className="w-4 h-4" />}
                                </div>
                            </foreignObject>
                            <text 
                                x={cx} 
                                y={y + 35} 
                                textAnchor="middle" 
                                fill={status === 'active' ? '#fff' : '#6b7280'}
                                fontSize="10" 
                                fontWeight="bold"
                                letterSpacing="1"
                                className={status === 'active' ? 'text-glow' : ''}
                            >
                                {node.label}
                            </text>
                        </g>
                    )
                })}
            </svg>
        </div>
    </div>
  );
};

export default PipelineVisualizer;