/**
 * NodeConfigPanelV2 - Configuration panel for AtomizerSpec v2.0 nodes
 * 
 * This component uses useSpecStore instead of the legacy useCanvasStore.
 * It renders type-specific configuration forms based on the selected node.
 * 
 * For custom extractors, integrates CodeEditorPanel with Claude AI generation.
 */

import { useState, useMemo, useCallback } from 'react';
import { Microscope, Trash2, X, AlertCircle, Code, FileCode } from 'lucide-react';
import { CodeEditorPanel } from './CodeEditorPanel';
import { generateExtractorCode, validateExtractorCode, streamExtractorCode, checkCodeDependencies, testExtractorCode } from '../../../lib/api/claude';
import {
  useSpecStore,
  useSpec,
  useSelectedNodeId,
  useSelectedNode,
} from '../../../hooks/useSpecStore';
import { usePanelStore } from '../../../hooks/usePanelStore';
import { FileBrowser } from './FileBrowser';
import {
  DesignVariable,
  Extractor,
  Objective,
  Constraint,
} from '../../../types/atomizer-spec';

// Common input class for dark theme
const inputClass = "w-full px-3 py-2 bg-dark-800 border border-dark-600 text-white placeholder-dark-400 rounded-lg focus:border-primary-500 focus:outline-none transition-colors";
const selectClass = "w-full px-3 py-2 bg-dark-800 border border-dark-600 text-white rounded-lg focus:border-primary-500 focus:outline-none transition-colors";
const labelClass = "block text-sm font-medium text-dark-300 mb-1";

interface NodeConfigPanelV2Props {
  /** Called when panel should close */
  onClose?: () => void;
}

export function NodeConfigPanelV2({ onClose }: NodeConfigPanelV2Props) {
  const spec = useSpec();
  const selectedNodeId = useSelectedNodeId();
  const selectedNode = useSelectedNode();
  const { updateNode, removeNode, clearSelection } = useSpecStore();
  
  const [showFileBrowser, setShowFileBrowser] = useState(false);
  const [isUpdating, setIsUpdating] = useState(false);
  const [error, setError] = useState<string | null>(null);

  // Determine node type from ID prefix or from the node itself
  const nodeType = useMemo(() => {
    if (!selectedNodeId) return null;
    
    // Synthetic nodes have fixed IDs
    if (selectedNodeId === 'model') return 'model';
    if (selectedNodeId === 'solver') return 'solver';
    if (selectedNodeId === 'algorithm') return 'algorithm';
    if (selectedNodeId === 'surrogate') return 'surrogate';
    
    // Real nodes have prefixed IDs
    const prefix = selectedNodeId.split('_')[0];
    switch (prefix) {
      case 'dv': return 'designVar';
      case 'ext': return 'extractor';
      case 'obj': return 'objective';
      case 'con': return 'constraint';
      default: return null;
    }
  }, [selectedNodeId]);

  // Get label for display
  const nodeLabel = useMemo(() => {
    if (!selectedNodeId || !spec) return 'Node';
    
    switch (nodeType) {
      case 'model': return spec.meta.study_name || 'Model';
      case 'solver': return spec.model.sim?.solution_type || 'Solver';
      case 'algorithm': return spec.optimization.algorithm?.type || 'Algorithm';
      case 'surrogate': return 'Neural Surrogate';
      default:
        if (selectedNode) {
          return (selectedNode as any).name || selectedNodeId;
        }
        return selectedNodeId;
    }
  }, [selectedNodeId, selectedNode, nodeType, spec]);

  // Handle field changes
  const handleChange = useCallback(async (field: string, value: unknown) => {
    if (!selectedNodeId || !selectedNode) return;
    
    setIsUpdating(true);
    setError(null);
    
    try {
      await updateNode(selectedNodeId, { [field]: value });
    } catch (err) {
      console.error('Failed to update node:', err);
      setError(err instanceof Error ? err.message : 'Update failed');
    } finally {
      setIsUpdating(false);
    }
  }, [selectedNodeId, selectedNode, updateNode]);

  // Handle delete
  const handleDelete = useCallback(async () => {
    if (!selectedNodeId) return;
    
    // Synthetic nodes can't be deleted
    if (['model', 'solver', 'algorithm', 'surrogate'].includes(selectedNodeId)) {
      setError('This node cannot be deleted');
      return;
    }
    
    setIsUpdating(true);
    setError(null);
    
    try {
      await removeNode(selectedNodeId);
      clearSelection();
      onClose?.();
    } catch (err) {
      console.error('Failed to delete node:', err);
      setError(err instanceof Error ? err.message : 'Delete failed');
    } finally {
      setIsUpdating(false);
    }
  }, [selectedNodeId, removeNode, clearSelection, onClose]);

  // Don't render if no node selected
  if (!selectedNodeId || !spec) {
    return null;
  }

  // Check if this is a synthetic node (model, solver, algorithm, surrogate)
  const isSyntheticNode = ['model', 'solver', 'algorithm', 'surrogate'].includes(selectedNodeId);

  return (
    <div className="w-80 bg-dark-850 border-l border-dark-700 flex flex-col h-full">
      {/* Header */}
      <div className="flex justify-between items-center p-4 border-b border-dark-700">
        <h3 className="font-semibold text-white truncate flex-1">
          Configure {nodeLabel}
        </h3>
        <div className="flex items-center gap-2">
          {!isSyntheticNode && (
            <button
              onClick={handleDelete}
              disabled={isUpdating}
              className="p-1.5 text-red-400 hover:text-red-300 hover:bg-red-500/10 rounded transition-colors"
              title="Delete node"
            >
              <Trash2 size={16} />
            </button>
          )}
          {onClose && (
            <button
              onClick={onClose}
              className="p-1.5 text-dark-400 hover:text-white hover:bg-dark-700 rounded transition-colors"
              title="Close panel"
            >
              <X size={16} />
            </button>
          )}
        </div>
      </div>

      {/* Error display */}
      {error && (
        <div className="mx-4 mt-4 p-3 bg-red-500/10 border border-red-500/30 rounded-lg flex items-start gap-2">
          <AlertCircle size={16} className="text-red-400 flex-shrink-0 mt-0.5" />
          <p className="text-sm text-red-400 flex-1">{error}</p>
          <button onClick={() => setError(null)} className="text-red-400 hover:text-red-300">
            <X size={14} />
          </button>
        </div>
      )}

      {/* Content */}
      <div className="flex-1 overflow-y-auto p-4">
        <div className="space-y-4">
          {/* Loading indicator */}
          {isUpdating && (
            <div className="text-xs text-primary-400 animate-pulse">Updating...</div>
          )}

          {/* Model node (synthetic) */}
          {nodeType === 'model' && spec.model && (
            <ModelNodeConfig spec={spec} />
          )}

          {/* Solver node (synthetic) */}
          {nodeType === 'solver' && (
            <SolverNodeConfig spec={spec} />
          )}

          {/* Algorithm node (synthetic) */}
          {nodeType === 'algorithm' && (
            <AlgorithmNodeConfig spec={spec} />
          )}

          {/* Surrogate node (synthetic) */}
          {nodeType === 'surrogate' && (
            <SurrogateNodeConfig spec={spec} />
          )}

          {/* Design Variable */}
          {nodeType === 'designVar' && selectedNode && (
            <DesignVarNodeConfig 
              node={selectedNode as DesignVariable} 
              onChange={handleChange}
            />
          )}

          {/* Extractor */}
          {nodeType === 'extractor' && selectedNode && (
            <ExtractorNodeConfig 
              node={selectedNode as Extractor} 
              onChange={handleChange}
            />
          )}

          {/* Objective */}
          {nodeType === 'objective' && selectedNode && (
            <ObjectiveNodeConfig 
              node={selectedNode as Objective} 
              onChange={handleChange}
            />
          )}

          {/* Constraint */}
          {nodeType === 'constraint' && selectedNode && (
            <ConstraintNodeConfig 
              node={selectedNode as Constraint} 
              onChange={handleChange}
            />
          )}
        </div>
      </div>

      {/* File Browser Modal */}
      <FileBrowser
        isOpen={showFileBrowser}
        onClose={() => setShowFileBrowser(false)}
        onSelect={() => {
          // This would update the model path - but model is synthetic
          setShowFileBrowser(false);
        }}
        fileTypes={['.sim', '.prt', '.fem', '.afem']}
      />

      {/* Introspection is now handled by FloatingIntrospectionPanel via usePanelStore */}
    </div>
  );
}

// ============================================================================
// Type-specific configuration components
// ============================================================================

interface SpecConfigProps {
  spec: NonNullable<ReturnType<typeof useSpec>>;
}

function ModelNodeConfig({ spec }: SpecConfigProps) {
  const { setIntrospectionData, openPanel } = usePanelStore();
  
  const handleOpenIntrospection = () => {
    // Set up introspection data and open the panel
    setIntrospectionData({
      filePath: spec.model.sim?.path || '',
      studyId: useSpecStore.getState().studyId || undefined,
    });
    openPanel('introspection');
  };
  
  return (
    <>
      <div>
        <label className={labelClass}>Model File</label>
        <input
          type="text"
          value={spec.model.sim?.path || ''}
          readOnly
          className={`${inputClass} font-mono text-sm bg-dark-900 cursor-not-allowed`}
          title="Model path is read-only. Change via study configuration."
        />
        <p className="text-xs text-dark-500 mt-1">Read-only. Set in study configuration.</p>
      </div>
      
      <div>
        <label className={labelClass}>Solver Type</label>
        <input
          type="text"
          value={spec.model.sim?.solution_type || 'Not detected'}
          readOnly
          className={`${inputClass} bg-dark-900 cursor-not-allowed`}
        />
      </div>

      {spec.model.sim?.path && (
        <button
          onClick={handleOpenIntrospection}
          className="w-full flex items-center justify-center gap-2 px-3 py-2.5 bg-primary-500/20
                     hover:bg-primary-500/30 border border-primary-500/30 rounded-lg
                     text-primary-400 text-sm font-medium transition-colors"
        >
          <Microscope size={16} />
          Introspect Model
        </button>
      )}
      
      {/* Note: IntrospectionPanel is now rendered by PanelContainer, not here */}
    </>
  );
}

function SolverNodeConfig({ spec }: SpecConfigProps) {
  return (
    <div>
      <label className={labelClass}>Solution Type</label>
      <input
        type="text"
        value={spec.model.sim?.solution_type || 'Not configured'}
        readOnly
        className={`${inputClass} bg-dark-900 cursor-not-allowed`}
        title="Solver type is determined by the model file."
      />
      <p className="text-xs text-dark-500 mt-1">Detected from model file.</p>
    </div>
  );
}

function AlgorithmNodeConfig({ spec }: SpecConfigProps) {
  const algo = spec.optimization.algorithm;
  
  return (
    <>
      <div>
        <label className={labelClass}>Method</label>
        <input
          type="text"
          value={algo?.type || 'TPE'}
          readOnly
          className={`${inputClass} bg-dark-900 cursor-not-allowed`}
        />
        <p className="text-xs text-dark-500 mt-1">Edit in optimization settings.</p>
      </div>
      
      <div>
        <label className={labelClass}>Max Trials</label>
        <input
          type="number"
          value={spec.optimization.budget?.max_trials || 100}
          readOnly
          className={`${inputClass} bg-dark-900 cursor-not-allowed`}
        />
      </div>
    </>
  );
}

function SurrogateNodeConfig({ spec }: SpecConfigProps) {
  const surrogate = spec.optimization.surrogate;
  
  return (
    <>
      <div className="flex items-center gap-2">
        <input
          type="checkbox"
          id="surrogate-enabled"
          checked={surrogate?.enabled || false}
          readOnly
          className="w-4 h-4 rounded bg-dark-800 border-dark-600 text-primary-500 cursor-not-allowed"
        />
        <label htmlFor="surrogate-enabled" className="text-sm font-medium text-dark-300">
          Neural Surrogate {surrogate?.enabled ? 'Enabled' : 'Disabled'}
        </label>
      </div>
      
      {surrogate?.enabled && (
        <>
          <div>
            <label className={labelClass}>Model Type</label>
            <input
              type="text"
              value={surrogate.type || 'MLP'}
              readOnly
              className={`${inputClass} bg-dark-900 cursor-not-allowed`}
            />
          </div>
          
          <div>
            <label className={labelClass}>Min Training Samples</label>
            <input
              type="number"
              value={surrogate.config?.min_training_samples || 20}
              readOnly
              className={`${inputClass} bg-dark-900 cursor-not-allowed`}
            />
          </div>
        </>
      )}
      
      <p className="text-xs text-dark-500">Edit in optimization settings.</p>
    </>
  );
}

// ============================================================================
// Editable node configs
// ============================================================================

interface DesignVarNodeConfigProps {
  node: DesignVariable;
  onChange: (field: string, value: unknown) => void;
}

function DesignVarNodeConfig({ node, onChange }: DesignVarNodeConfigProps) {
  return (
    <>
      <div>
        <label className={labelClass}>Name</label>
        <input
          type="text"
          value={node.name}
          onChange={(e) => onChange('name', e.target.value)}
          className={inputClass}
        />
      </div>
      
      <div>
        <label className={labelClass}>Expression Name</label>
        <input
          type="text"
          value={node.expression_name}
          onChange={(e) => onChange('expression_name', e.target.value)}
          placeholder="NX expression name"
          className={`${inputClass} font-mono text-sm`}
        />
      </div>
      
      <div className="grid grid-cols-2 gap-2">
        <div>
          <label className={labelClass}>Min</label>
          <input
            type="number"
            value={node.bounds.min}
            onChange={(e) => onChange('bounds', { ...node.bounds, min: parseFloat(e.target.value) })}
            className={inputClass}
          />
        </div>
        <div>
          <label className={labelClass}>Max</label>
          <input
            type="number"
            value={node.bounds.max}
            onChange={(e) => onChange('bounds', { ...node.bounds, max: parseFloat(e.target.value) })}
            className={inputClass}
          />
        </div>
      </div>
      
      {node.baseline !== undefined && (
        <div>
          <label className={labelClass}>Baseline</label>
          <input
            type="number"
            value={node.baseline}
            onChange={(e) => onChange('baseline', parseFloat(e.target.value))}
            className={inputClass}
          />
        </div>
      )}
      
      <div>
        <label className={labelClass}>Units</label>
        <input
          type="text"
          value={node.units || ''}
          onChange={(e) => onChange('units', e.target.value)}
          placeholder="mm"
          className={inputClass}
        />
      </div>

      <div className="flex items-center gap-2">
        <input
          type="checkbox"
          id={`${node.id}-enabled`}
          checked={node.enabled !== false}
          onChange={(e) => onChange('enabled', e.target.checked)}
          className="w-4 h-4 rounded bg-dark-800 border-dark-600 text-primary-500 focus:ring-primary-500"
        />
        <label htmlFor={`${node.id}-enabled`} className="text-sm text-dark-300">
          Enabled
        </label>
      </div>
    </>
  );
}

interface ExtractorNodeConfigProps {
  node: Extractor;
  onChange: (field: string, value: unknown) => void;
}

// Default template for custom extractors
const DEFAULT_EXTRACTOR_TEMPLATE = `"""
Custom Extractor Function

This function is called after FEA simulation completes.
It receives the results and should return extracted values.
"""

from pyNastran.op2.op2 import OP2
import numpy as np

def extract(op2_path: str, fem_path: str, params: dict, subcase_id: int = 1) -> dict:
    """
    Extract physics from FEA results.
    
    Args:
        op2_path: Path to OP2 results file
        fem_path: Path to FEM file
        params: Current design variable values
        subcase_id: Subcase ID to analyze
        
    Returns:
        Dict with extracted values, e.g. {'max_stress': 150.5, 'mass': 2.3}
    """
    # Load OP2 results
    op2 = OP2()
    op2.read_op2(op2_path)
    
    # Example: Extract max displacement
    if subcase_id in op2.displacements:
        disp = op2.displacements[subcase_id]
        magnitudes = np.sqrt(np.sum(disp.data[0, :, 1:4]**2, axis=1))
        max_disp = float(np.max(magnitudes))
    else:
        max_disp = 0.0
    
    return {
        'max_displacement': max_disp,
    }
`;

function ExtractorNodeConfig({ node, onChange }: ExtractorNodeConfigProps) {
  const [showCodeEditor, setShowCodeEditor] = useState(false);
  const studyId = useSpecStore(state => state.studyId);
  
  const extractorOptions = [
    { id: 'E1', name: 'Displacement', type: 'displacement' },
    { id: 'E2', name: 'Frequency', type: 'frequency' },
    { id: 'E3', name: 'Solid Stress', type: 'solid_stress' },
    { id: 'E4', name: 'BDF Mass', type: 'mass_bdf' },
    { id: 'E5', name: 'CAD Mass', type: 'mass_expression' },
    { id: 'E8', name: 'Zernike (OP2)', type: 'zernike_op2' },
    { id: 'E9', name: 'Zernike (CSV)', type: 'zernike_csv' },
    { id: 'E10', name: 'Zernike (RMS)', type: 'zernike_rms' },
  ];

  // Check if this is a custom function type
  // Using string comparison to handle both 'custom_function' and potential legacy 'custom' values
  const isCustomType = node.type === 'custom_function' || (node.type as string) === 'custom';
  
  // Get current source code
  const currentCode = node.function?.source_code || DEFAULT_EXTRACTOR_TEMPLATE;
  
  // Handle Claude generation request (non-streaming fallback)
  const handleRequestGeneration = useCallback(async (prompt: string): Promise<string> => {
    const response = await generateExtractorCode({
      prompt,
      study_id: studyId || undefined,
      existing_code: node.function?.source_code,
      output_names: node.outputs?.map(o => o.name) || [],
    });
    return response.code;
  }, [studyId, node.function?.source_code, node.outputs]);
  
  // Handle streaming generation (preferred)
  const handleStreamingGeneration = useCallback((
    request: { prompt: string; study_id?: string; existing_code?: string; output_names?: string[] },
    callbacks: { onToken: (t: string) => void; onComplete: (c: string, o: string[]) => void; onError: (e: string) => void }
  ) => {
    return streamExtractorCode(request, callbacks);
  }, []);
  
  // Handle code change from editor
  const handleCodeChange = useCallback((code: string) => {
    onChange('function', {
      ...node.function,
      name: node.function?.name || 'custom_extract',
      source_code: code,
    });
  }, [node.function, onChange]);
  
  // Handle code validation (includes syntax check and dependency check)
  const handleValidateCode = useCallback(async (code: string) => {
    // First check syntax
    const syntaxResult = await validateExtractorCode(code);
    if (!syntaxResult.valid) {
      return {
        success: false,
        error: syntaxResult.error,
      };
    }
    
    // Then check dependencies
    const depResult = await checkCodeDependencies(code);
    
    // Build combined result
    const warnings: string[] = [...depResult.warnings];
    if (depResult.missing.length > 0) {
      warnings.push(`Missing packages: ${depResult.missing.join(', ')}`);
    }
    
    return {
      success: true,
      error: warnings.length > 0 ? `Warnings: ${warnings.join('; ')}` : undefined,
      outputs: depResult.imports.length > 0 ? { imports: depResult.imports.join(', ') } : undefined,
    };
  }, []);
  
  // Handle live testing against OP2 file
  const handleTestCode = useCallback(async (code: string) => {
    const result = await testExtractorCode({
      code,
      study_id: studyId || undefined,
      subcase_id: 1,
    });
    return result;
  }, [studyId]);

  return (
    <>
      <div>
        <label className={labelClass}>Name</label>
        <input
          type="text"
          value={node.name}
          onChange={(e) => onChange('name', e.target.value)}
          className={inputClass}
        />
      </div>
      
      <div>
        <label className={labelClass}>Extractor Type</label>
        <select
          value={node.type}
          onChange={(e) => onChange('type', e.target.value)}
          className={selectClass}
        >
          <option value="">Select...</option>
          {extractorOptions.map(opt => (
            <option key={opt.id} value={opt.type}>
              {opt.id} - {opt.name}
            </option>
          ))}
          <option value="custom_function">Custom Function</option>
        </select>
      </div>

      {/* Custom Code Editor Button */}
      {isCustomType && (
        <>
          <button
            onClick={() => setShowCodeEditor(true)}
            className="w-full flex items-center justify-center gap-2 px-3 py-2.5 
                       bg-violet-500/20 hover:bg-violet-500/30 border border-violet-500/30 
                       rounded-lg text-violet-400 text-sm font-medium transition-colors"
          >
            <Code size={16} />
            Edit Custom Code
          </button>
          
          {node.function?.source_code && (
            <div className="text-xs text-dark-500 flex items-center gap-1.5">
              <FileCode size={12} />
              Custom code defined ({node.function.source_code.split('\n').length} lines)
            </div>
          )}
        </>
      )}

      {/* Code Editor Modal */}
      {showCodeEditor && (
        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/60 backdrop-blur-sm">
          <div className="w-[900px] h-[700px] bg-dark-850 rounded-xl overflow-hidden shadow-2xl border border-dark-600 flex flex-col">
            {/* Code Editor with built-in header containing toolbar buttons */}
            <CodeEditorPanel
              initialCode={currentCode}
              extractorName={`Custom Extractor: ${node.name}`}
              outputs={node.outputs?.map(o => o.name) || []}
              onChange={handleCodeChange}
              onRequestGeneration={handleRequestGeneration}
              onRequestStreamingGeneration={handleStreamingGeneration}
              onRun={handleValidateCode}
              onTest={handleTestCode}
              onClose={() => setShowCodeEditor(false)}
              showHeader={true}
              height="100%"
              studyId={studyId || undefined}
            />
          </div>
        </div>
      )}

      {/* Outputs */}
      <div>
        <label className={labelClass}>Outputs</label>
        <input
          type="text"
          value={node.outputs?.map(o => o.name).join(', ') || ''}
          readOnly
          placeholder="value, unit"
          className={`${inputClass} bg-dark-900 cursor-not-allowed`}
        />
        <p className="text-xs text-dark-500 mt-1">
          {isCustomType 
            ? 'Detected from return statement in code.' 
            : 'Outputs are defined by extractor type.'}
        </p>
      </div>
    </>
  );
}

interface ObjectiveNodeConfigProps {
  node: Objective;
  onChange: (field: string, value: unknown) => void;
}

function ObjectiveNodeConfig({ node, onChange }: ObjectiveNodeConfigProps) {
  return (
    <>
      <div>
        <label className={labelClass}>Name</label>
        <input
          type="text"
          value={node.name}
          onChange={(e) => onChange('name', e.target.value)}
          className={inputClass}
        />
      </div>
      
      <div>
        <label className={labelClass}>Direction</label>
        <select
          value={node.direction}
          onChange={(e) => onChange('direction', e.target.value)}
          className={selectClass}
        >
          <option value="minimize">Minimize</option>
          <option value="maximize">Maximize</option>
        </select>
      </div>
      
      <div>
        <label className={labelClass}>Weight</label>
        <input
          type="number"
          step="0.1"
          min="0"
          value={node.weight ?? 1}
          onChange={(e) => onChange('weight', parseFloat(e.target.value))}
          className={inputClass}
        />
      </div>

      {node.target !== undefined && (
        <div>
          <label className={labelClass}>Target Value</label>
          <input
            type="number"
            value={node.target}
            onChange={(e) => onChange('target', parseFloat(e.target.value))}
            className={inputClass}
          />
        </div>
      )}
    </>
  );
}

interface ConstraintNodeConfigProps {
  node: Constraint;
  onChange: (field: string, value: unknown) => void;
}

function ConstraintNodeConfig({ node, onChange }: ConstraintNodeConfigProps) {
  return (
    <>
      <div>
        <label className={labelClass}>Name</label>
        <input
          type="text"
          value={node.name}
          onChange={(e) => onChange('name', e.target.value)}
          className={inputClass}
        />
      </div>
      
      <div className="grid grid-cols-2 gap-2">
        <div>
          <label className={labelClass}>Type</label>
          <select
            value={node.type}
            onChange={(e) => onChange('type', e.target.value)}
            className={selectClass}
          >
            <option value="less_than">&lt; Less than</option>
            <option value="less_equal">&lt;= Less or equal</option>
            <option value="greater_than">&gt; Greater than</option>
            <option value="greater_equal">&gt;= Greater or equal</option>
            <option value="equal">= Equal</option>
          </select>
        </div>
        <div>
          <label className={labelClass}>Threshold</label>
          <input
            type="number"
            value={node.threshold}
            onChange={(e) => onChange('threshold', parseFloat(e.target.value))}
            className={inputClass}
          />
        </div>
      </div>

    </>
  );
}

export default NodeConfigPanelV2;