'use strict';

var pathUtils = require('../util/path');

/*
	Get a path relative to the site path.
*/
function relatePath(absolutePath, siteAbsolutePath) {
  var relativePath = [];

  // At this point, it's related to the host/port
  var related = true;
  var parentIndex = -1;

  // Find parents
  siteAbsolutePath.forEach(function (siteAbsoluteDir, i) {
    if (related) {
      if (absolutePath[i] !== siteAbsoluteDir) {
        related = false;
      } else {
        parentIndex = i;
      }
    }

    if (!related) {
      // Up one level
      relativePath.push('..');
    }
  });

  // Form path
  absolutePath.forEach(function (dir, i) {
    if (i > parentIndex) {
      relativePath.push(dir);
    }
  });

  return relativePath;
}

function relativize(urlObj, siteUrlObj, options) {
  if (urlObj.extra.relation.minimumScheme) {
    var pathArray = relatePath(
      urlObj.path.absolute.array,
      siteUrlObj.path.absolute.array
    );

    urlObj.path.relative.array = pathArray;
    urlObj.path.relative.string = pathUtils.join(pathArray);
  }
}

module.exports = relativize;