import type { AnalysisResult } from '../analysis/analyzer';

/**
 * The colour of a test's icon, the same on the score card and in the
 * analysis: passed green, failed red, amber for a failed test that counts
 * for nothing (advice) or one that earned part of its points, and grey for
 * a test that is shown for comparison only, whatever it found.
 *
 * @param {AnalysisResult} result - One test.
 * @returns {string} The icon's background and text classes.
 */
export const resultTone = (result: AnalysisResult): string => {
  if (result.rankMathOnly) {
    return 'bg-muted text-muted-foreground';
  }
  if (result.partial) {
    return 'bg-amber-500/15 text-amber-600 dark:text-amber-400';
  }
  if (result.passed) {
    return 'bg-emerald-500/15 text-emerald-600 dark:text-emerald-400';
  }
  return result.max === 0
    ? 'bg-amber-500/15 text-amber-600 dark:text-amber-400'
    : 'bg-red-500/15 text-red-600 dark:text-red-400';
};

/**
 * Whether a test is something to do: failed, or passed for part of its
 * points, and either weighed or advice.
 *
 * @param {AnalysisResult} result - One test.
 * @returns {boolean} True when it belongs in the list of what to fix.
 */
export const isToDo = (result: AnalysisResult): boolean =>
  (!result.passed || Boolean(result.partial)) && !result.rankMathOnly;

/**
 * Whether a test costs points outright: weighed and failed, as opposed to
 * advice or a test that earned part of its points.
 *
 * @param {AnalysisResult} result - One test.
 * @returns {boolean} True when it belongs under "to fix".
 */
export const isToFix = (result: AnalysisResult): boolean =>
  !result.passed && result.max > 0 && !result.rankMathOnly;

/**
 * What the tests that are not fully passed add up to, in the words the
 * header's count uses: the ones that cost points outright are "to fix",
 * the ones that earned part of them and the advice are "to improve".
 *
 * @param {AnalysisResult[]} failing - The tests not fully passed.
 * @returns {string} e.g. "2 to fix, 6 to improve".
 */
export const todoSummary = (failing: AnalysisResult[]): string => {
  const toFix = failing.filter(isToFix).length;
  const toImprove = failing.length - toFix;
  return [
    toFix > 0 ? `${toFix} to fix` : '',
    toImprove > 0 ? `${toImprove} to improve` : '',
  ]
    .filter(Boolean)
    .join(', ');
};