import type { ProductSearchResult, ProductSpec } from "./types.js";

function parseDimensionNumber(text: string): number | undefined {
  const match = text.match(/([0-9]+(?:\.[0-9]+)?)/);
  return match ? Number(match[1]) : undefined;
}

function isOverallWidthSpec(spec: ProductSpec): boolean {
  const name = spec.name.toLowerCase();
  if (/seat|arm|door|package|box|back|cushion/.test(name)) {
    return false;
  }
  return /width|dimensions?/.test(name);
}

function widthFromSpec(spec: ProductSpec): number | undefined {
  if (!isOverallWidthSpec(spec)) {
    return undefined;
  }

  const name = spec.name.toLowerCase();
  const value = spec.value;
  const labeledWidth = value.match(/([0-9]+(?:\.[0-9]+)?)\s*(?:"|in(?:ches?)?)?\s*W\b/i);
  if (labeledWidth) {
    return Number(labeledWidth[1]);
  }

  if (/width/.test(name)) {
    return parseDimensionNumber(value);
  }

  const orderMatch = name.match(/\b([dwh])\s*x\s*([dwh])(?:\s*x\s*([dwh]))?\b/i);
  if (orderMatch) {
    const order = orderMatch.slice(1).filter(Boolean).map((part) => part.toLowerCase());
    const widthIndex = order.indexOf("w");
    const values = value.match(/[0-9]+(?:\.[0-9]+)?/g)?.map(Number) ?? [];
    if (widthIndex >= 0 && values[widthIndex] !== undefined) {
      return values[widthIndex];
    }
  }

  return undefined;
}

export function extractWidthInches(product: ProductSearchResult): number | undefined {
  for (const spec of product.specs) {
    const width = widthFromSpec(spec);
    if (width !== undefined) {
      return width;
    }
  }

  const titleMatch = product.title.match(/\b([0-9]+(?:\.[0-9]+)?)\s*(?:["”]|in(?:ch(?:es)?)?)\b/i);
  return titleMatch ? Number(titleMatch[1]) : undefined;
}

export function formatWidthInches(width: number | undefined): string {
  if (width === undefined) {
    return "unknown";
  }
  return `${Number.isInteger(width) ? width.toFixed(0) : width.toFixed(1)}"`;
}