import React from 'react';
import { Handle, Position, useReactFlow, useUpdateNodeInternals } from '@xyflow/react';
import { useTranslation } from 'react-i18next';
import { HelpCircle } from 'lucide-react';
import { isDefaultLabel } from '../../utils';

const ConditionNode = ({ id, data, selected }) => {
  const { t } = useTranslation();
  const { setNodes } = useReactFlow();
  const updateNodeInternals = useUpdateNodeInternals();

  const getOptions = () => {
    if (data.options && data.options.length > 0) {
      return data.options;
    }
    return [
      { id: 'opt-yes', label: t('common.yes', 'Yes') },
      { id: 'opt-no', label: t('common.no', 'No') }
    ];
  };

  const getSelectedOptions = () => {
    if (data.selectedOptions) {
      return data.selectedOptions;
    }
    if (data.decision === 'True') return ['opt-yes'];
    if (data.decision === 'False') return ['opt-no'];
    return [];
  };

  const toggleOption = (optionId) => {
    const currentSelected = getSelectedOptions();
    const isMultiSelect = !!data.multiSelect;
    
    let newSelected;
    if (isMultiSelect) {
      if (currentSelected.includes(optionId)) {
        newSelected = currentSelected.filter(id => id !== optionId);
      } else {
        newSelected = [...currentSelected, optionId];
      }
    } else {
      if (currentSelected.includes(optionId)) {
        newSelected = []; // Unselect
      } else {
        newSelected = [optionId]; // Select only this one
      }
    }
    
    if (data.updateNodeData) {
      data.updateNodeData(id, { selectedOptions: newSelected, decision: undefined });
    } else {
      setNodes((nds) => 
        nds.map((n) => n.id === id ? { ...n, data: { ...n.data, selectedOptions: newSelected, decision: undefined } } : n)
      );
    }
  };

  const handleConfigure = (e) => {
    e.stopPropagation();
    window.dispatchEvent(new CustomEvent('configure-condition-node', { detail: { nodeId: id } }));
  };

  const options = getOptions();
  const selectedOptions = getSelectedOptions();
  const serializedOptions = JSON.stringify(options);

  React.useEffect(() => {
    const timer = setTimeout(() => {
      updateNodeInternals(id);
    }, 50);
    return () => clearTimeout(timer);
  }, [id, serializedOptions, updateNodeInternals]);

  const labelText = isDefaultLabel(data.label) ? t('canvas.new_condition', 'New Condition?') : data.label;
  const labelLength = labelText.length;

  // Use a beautifully scaled static node container size of 200px to ensure
  // React Flow edge anchors are always 100% stable and perfectly snapped.
  const size = 200;
  const center = size / 2;

  // Choose optimal font size based on text length to ensure it always fits beautifully
  let fontSizeClass = 'text-sm';
  if (labelLength > 80) {
    fontSizeClass = 'text-[11px]';
  } else if (labelLength > 50) {
    fontSizeClass = 'text-xs';
  }

  // Symmetrical placement generator for outer corner handles and badges fanned out radially
  const getHandleCoords = (index, total) => {
    let angle;
    if (total === 1) {
      angle = Math.PI / 2; // Straight down
    } else {
      // Distribute evenly across the bottom half-circle (from Math.PI [Left] to 0 [Right])
      angle = Math.PI - (index / (total - 1)) * Math.PI;
    }
    
    const cosA = Math.cos(angle);
    const sinA = Math.sin(angle);
    
    // Intersection of radial ray with the boundary of a diamond of half-diagonal = center (100)
    const r = center / (Math.abs(cosA) + Math.abs(sinA));
    const x = center + r * cosA;
    const y = center + r * sinA;
    
    // Choose the React Flow handle side based on direction
    let pos = Position.Bottom;
    if (cosA < -0.5) {
      pos = Position.Left;
    } else if (cosA > 0.5) {
      pos = Position.Right;
    }
    
    // Dynamic offsets based on total count to prevent overlapping
    const badgeOffset = 45 + Math.max(0, (total - 2) * 8);
    const pinOffset = badgeOffset + 35;
    
    return {
      x, // Diamond edge x
      y, // Diamond edge y
      pos,
      // Badge center
      bx: center + (r + badgeOffset) * cosA,
      by: center + (r + badgeOffset) * sinA,
      // Pin center
      px: center + (r + pinOffset) * cosA,
      py: center + (r + pinOffset) * sinA,
      angle
    };
  };

  return (
    <div 
      onDoubleClick={handleConfigure}
      className={`relative group transition-all duration-200 ${
        selected ? '-translate-y-1.5 scale-[1.02]' : ''
      }`}
      style={{
        width: `${size}px`,
        height: `${size}px`
      }}
    >
      {/* Target input handle (placed exactly at the visual top corner of the diamond) */}
      <Handle 
        type="target" 
        position={Position.Top} 
        id="main-target"
        className="!bg-surface-container-lowest !w-4 !h-4 !border-[3px] !border-primary shadow-[0_2px_4px_rgba(0,0,0,0.1)] hover:scale-120 transition-all !z-50 !absolute" 
        style={{ 
          position: 'absolute',
          left: `${center}px`, 
          top: '0px', 
          bottom: 'auto',
          right: 'auto',
          transform: 'translate(-50%, -50%)'
        }}
      />

      {/* Dynamic connecting lines between handles and badges */}
      <svg className="absolute inset-0 pointer-events-none overflow-visible z-30">
        {options.map((option, index) => {
          const coords = getHandleCoords(index, options.length);
          const isSelected = selectedOptions.includes(option.id);

          return (
            <line
              key={`line-${option.id}-${options.length}-${coords.pos}-${Math.round(coords.px)}-${Math.round(coords.py)}`}
              x1={coords.x}
              y1={coords.y}
              x2={coords.px}
              y2={coords.py}
              stroke={isSelected ? '#22c55e' : 'var(--color-primary)'}
              strokeWidth={isSelected ? '2' : '1.5'}
              strokeDasharray={isSelected ? 'none' : '3 3'}
              className={isSelected ? 'opacity-85 transition-all duration-300' : 'opacity-35 transition-all duration-300'}
            />
          );
        })}
      </svg>

      {/* The Rotated Diamond Shape Background */}
      <div 
        className={`absolute rounded-[2rem] rough-border bg-surface-container-lowest transition-all ${
          selected ? 'border-emerald-400 ring-4 ring-emerald-400/20' : ''
        }`}
        style={{
          left: '50%',
          top: '50%',
          width: `${size / 1.4142}px`,
          height: `${size / 1.4142}px`,
          transform: 'translate(-50%, -50%) rotate(45deg)',
          boxShadow: selected ? '6px 6px 0px 0px rgba(52, 211, 153, 0.3), inset 0 0 0 1px rgba(0,0,0,0.05)' : 'none',
          pointerEvents: 'none'
        }}
      />

      {/* Unrotated Text Content (centered perfectly over the rotated background diamond) */}
      <div 
        className="absolute left-1/2 top-1/2 -translate-x-1/2 -translate-y-1/2 flex flex-col items-center justify-center text-center cursor-pointer select-none z-10 pointer-events-none"
        style={{
          width: `${size * 0.65}px`,
          height: `${size * 0.65}px`
        }}
      >
        <HelpCircle size={18} className="text-primary/60 mb-1 flex-shrink-0 pointer-events-none" />
        <span 
          className={`font-display-lg ${fontSizeClass} text-primary leading-tight break-words text-center pointer-events-none`}
          style={{
            maxWidth: `${size * 0.58}px`
          }}
        >
          {labelText}
        </span>
      </div>

      {/* Customizable Dynamic Option Badges & Source Handles along the perimeter */}
      {options.map((option, index) => {
        const coords = getHandleCoords(index, options.length);
        const isSelected = selectedOptions.includes(option.id);

        return (
          <React.Fragment key={`${option.id}-${options.length}-${coords.pos}-${Math.round(coords.px)}-${Math.round(coords.py)}`}>
            {/* The React Flow Source Handle placed exactly at the outer radial pinCoords */}
            <Handle 
              type="source" 
              position={coords.pos} 
              id={option.id} 
              className="!bg-transparent !w-6 !h-6 !border-0 hover:scale-125 transition-all !z-50 !absolute cursor-crosshair flex items-center justify-center"
              style={{ 
                position: 'absolute',
                left: `${coords.px}px`, 
                top: `${coords.py}px`,
                bottom: 'auto',
                right: 'auto',
                transform: 'translate(-50%, -50%)'
              }}
            >
              {/* Visual dot on the outer pin position */}
              <div className={`w-3.5 h-3.5 rounded-full border-2 shadow-sm pointer-events-none transition-all ${
                isSelected 
                  ? 'bg-[#22c55e] border-white scale-110' 
                  : 'bg-primary border-white'
              }`} />
            </Handle>
            
            {/* Floating text badge fanned out radially between the diamond and the pin */}
            <div 
              className="absolute whitespace-normal break-words max-w-[110px] pointer-events-auto z-40 text-center flex items-center justify-center"
              style={{ 
                left: `${coords.bx}px`, 
                top: `${coords.by}px`,
                transform: 'translate(-50%, -50%)' 
              }}
            >
              <button
                onClick={(e) => {
                  e.stopPropagation();
                  toggleOption(option.id);
                }}
                className={`px-3 py-1.5 min-w-[50px] text-[10px] font-bold uppercase tracking-wider rounded-md border-2 border-primary shadow-[2px_2px_0px_0px_var(--color-primary)] hover:scale-105 active:scale-95 transition-all cursor-pointer leading-tight ${
                  isSelected 
                    ? 'bg-[#22c55e] text-white border-primary' 
                    : 'bg-surface-container-lowest text-primary hover:bg-surface-variant'
                }`}
              >
                {option.label}
              </button>
            </div>
          </React.Fragment>
        );
      })}
    </div>
  );
};

export default ConditionNode;