stock-bot/apps/wcag-ada/shared/src/utils.ts
2025-06-28 11:11:34 -04:00

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5.8 KiB
TypeScript

import type { ImpactValue } from 'axe-core';
import { IMPACT_SCORES, COMPLIANCE_THRESHOLDS, WCAG_TAGS } from './constants';
import type { AccessibilityScanResult, ScanSummary, WCAGLevel } from './types';
export function calculateComplianceScore(result: AccessibilityScanResult): number {
const { violations, passes } = result;
const totalChecks = violations.length + passes.length;
if (totalChecks === 0) return 100;
let weightedViolations = 0;
violations.forEach(violation => {
const impactScore = IMPACT_SCORES[violation.impact as keyof typeof IMPACT_SCORES] || 50;
weightedViolations += (impactScore / 100) * violation.nodes.length;
});
const score = Math.max(0, 100 - (weightedViolations / totalChecks) * 100);
return Math.round(score * 100) / 100;
}
export function isCompliantWithLevel(score: number, level: WCAGLevel['level']): boolean {
return score >= COMPLIANCE_THRESHOLDS[level] * 100;
}
export function getWCAGTags(level: WCAGLevel): string[] {
const key = `WCAG_${level.version.replace('.', '_')}_${level.level}` as keyof typeof WCAG_TAGS;
return [...(WCAG_TAGS[key] || [])];
}
export function summarizeViolations(violations: AccessibilityScanResult['violations']): Partial<ScanSummary> {
const summary = {
criticalIssues: 0,
seriousIssues: 0,
moderateIssues: 0,
minorIssues: 0,
};
violations.forEach(violation => {
const count = violation.nodes.length;
switch (violation.impact) {
case 'critical':
summary.criticalIssues += count;
break;
case 'serious':
summary.seriousIssues += count;
break;
case 'moderate':
summary.moderateIssues += count;
break;
case 'minor':
summary.minorIssues += count;
break;
}
});
return summary;
}
export function generateFixSuggestion(violationId: string): string {
const suggestions: Record<string, string> = {
'color-contrast': 'Increase the contrast ratio between text and background colors to meet WCAG standards.',
'image-alt': 'Add descriptive alt text to images. Use alt="" for decorative images.',
'label': 'Add labels to form controls using <label> elements or aria-label attributes.',
'button-name': 'Provide accessible names for buttons using text content, aria-label, or aria-labelledby.',
'link-name': 'Ensure links have descriptive text that explains their purpose.',
'heading-order': 'Use heading levels in sequential order without skipping levels.',
'landmark-one-main': 'Ensure the page has one main landmark using <main> or role="main".',
'page-has-heading-one': 'Add a single <h1> element to identify the main content of the page.',
'meta-viewport': 'Avoid disabling zoom by not using maximum-scale=1.0 in viewport meta tag.',
'duplicate-id': 'Ensure all id attributes are unique within the page.',
'aria-required-attr': 'Add all required ARIA attributes for the role being used.',
'aria-valid-attr': 'Use only valid ARIA attributes that are spelled correctly.',
'html-has-lang': 'Add a lang attribute to the <html> element to specify the page language.',
'document-title': 'Provide a descriptive <title> element in the document head.',
'list': 'Ensure <ul> and <ol> elements only contain <li>, <script>, or <template> elements.',
};
return suggestions[violationId] || 'Review the element and ensure it meets accessibility standards.';
}
export function formatViolationTarget(target: string[]): string {
return target.join(' > ');
}
export function estimateFixTime(impact: ImpactValue, nodeCount: number): number {
const baseTime: Record<ImpactValue, number> = {
critical: 30,
serious: 20,
moderate: 15,
minor: 10,
};
return (baseTime[impact] || 15) * nodeCount;
}
export function groupViolationsByWCAGCriteria(
violations: AccessibilityScanResult['violations']
): Record<string, AccessibilityScanResult['violations']> {
const grouped: Record<string, AccessibilityScanResult['violations']> = {};
violations.forEach(violation => {
violation.wcagCriteria?.forEach(criterion => {
if (!grouped[criterion]) {
grouped[criterion] = [];
}
grouped[criterion].push(violation);
});
});
return grouped;
}
export function generateComplianceStatement(result: AccessibilityScanResult): string {
const { wcagCompliance, summary } = result;
const score = result.summary.score;
const level = wcagCompliance.level;
if (wcagCompliance.isCompliant) {
return `This page meets WCAG ${level.version} Level ${level.level} compliance standards with a score of ${score}%.`;
}
const majorIssues = summary.criticalIssues + summary.seriousIssues;
return `This page does not meet WCAG ${level.version} Level ${level.level} compliance. ` +
`Found ${majorIssues} major accessibility issues that need to be addressed. ` +
`Current compliance score: ${score}%.`;
}
export function extractPageMetadata(html: string): Partial<AccessibilityScanResult['pageMetadata']> {
const metadata: Partial<AccessibilityScanResult['pageMetadata']> = {};
// Extract title
const titleMatch = html.match(/<title[^>]*>([^<]+)<\/title>/i);
if (titleMatch) {
metadata.title = titleMatch[1].trim();
}
// Extract language
const langMatch = html.match(/<html[^>]*lang=["']([^"']+)["']/i);
if (langMatch) {
metadata.language = langMatch[1];
}
// Count elements
metadata.imagesCount = (html.match(/<img[^>]*>/gi) || []).length;
metadata.formsCount = (html.match(/<form[^>]*>/gi) || []).length;
metadata.linksCount = (html.match(/<a[^>]*>/gi) || []).length;
// Check for landmarks
metadata.hasLandmarks = /<(main|nav|aside|header|footer)[^>]*>|role=["'](main|navigation|complementary|banner|contentinfo)["']/i.test(html);
// Check for headings
metadata.hasHeadings = /<h[1-6][^>]*>/i.test(html);
return metadata;
}