export interface UVQualityReport {
  missingUVs: boolean;
  extremeStretching: boolean;
  overlappingUVs: boolean;
  highComplexity: boolean;
  recommendTriplanar: boolean;
  details: {
    vertexCount: number;
    uvRange: [number, number];
  };
}

export function analyzeUVQuality(
  positions: Float32Array,
  uvs?: Float32Array,
  indices?: Uint32Array | Uint16Array
): UVQualityReport {
  const vertexCount = positions.length / 3;
  const highComplexity = vertexCount > 50000; // Arbitrary threshold for complex geometry

  if (!uvs || uvs.length === 0) {
    return {
      missingUVs: true,
      extremeStretching: false,
      overlappingUVs: false,
      highComplexity,
      recommendTriplanar: true,
      details: {
        vertexCount,
        uvRange: [0, 0]
      }
    };
  }

  let minU = Infinity, maxU = -Infinity;
  let minV = Infinity, maxV = -Infinity;

  for (let i = 0; i < uvs.length; i += 2) {
    const u = uvs[i];
    const v = uvs[i + 1];
    
    if (u < minU) minU = u;
    if (u > maxU) maxU = u;
    if (v < minV) minV = v;
    if (v > maxV) maxV = v;
  }

  const uRange = maxU - minU;
  const vRange = maxV - minV;
  
  // Basic heuristic: if UVs are heavily clamped or barely cover any area
  const extremeStretching = (uRange < 0.01 && uRange > 0) || (vRange < 0.01 && vRange > 0);
  
  // Overlapping detection is computationally expensive, skipping deep check for now
  // A robust check would require comparing triangle areas in UV space vs World space
  const overlappingUVs = false; 

  const recommendTriplanar = extremeStretching || highComplexity;

  return {
    missingUVs: false,
    extremeStretching,
    overlappingUVs,
    highComplexity,
    recommendTriplanar,
    details: {
      vertexCount,
      uvRange: [uRange, vRange]
    }
  };
}