import path from 'node:path';
import { FOLDERS, FILES } from '../core/constants.js';

export function resolvePagesUrlPrefix(frontendRoot: string, pagesRoot: string): string {
  const relative = path.relative(frontendRoot, pagesRoot).replace(/\\/g, '/');
  if (!relative || relative === '.' || relative.startsWith('..')) {
    return '';
  }
  return `/${trimSlashes(relative)}`;
}

export function isRootPagesLayout(frontendRoot: string, pagesRoot: string): boolean {
  return resolvePagesUrlPrefix(frontendRoot, pagesRoot) === '';
}

export function resolvePageAssetUrl(
  pagesUrlPrefix: string,
  pageName: string,
  fileName: string,
): string {
  return joinUrl(pagesUrlPrefix, pageName, fileName);
}

export function resolvePageHtmlUrl(
  pagesUrlPrefix: string,
  pageName: string,
  useRootIndex: boolean,
): string {
  if (useRootIndex && pageName === FOLDERS.home) {
    return `/${FILES.indexHtml}`;
  }
  return joinUrl(pagesUrlPrefix, pageName, FILES.indexHtml);
}

export function resolvePageHtmlDir(
  pagesRoot: string,
  pageName: string,
  useRootIndex: boolean,
): string {
  if (useRootIndex && pageName === FOLDERS.home) {
    return pagesRoot;
  }
  return path.join(pagesRoot, pageName);
}

function joinUrl(...segments: string[]): string {
  const cleaned = segments
    .map((segment) => trimSlashes(segment))
    .filter((segment) => segment.length > 0);
  return `/${cleaned.join('/')}`;
}

function trimSlashes(value: string): string {
  return value.replace(/^\/+|\/+$/g, '');
}