{
  "$schema": "../schemas/rule.schema.json",
  "id": "accessibility",
  "version": "1.0.0",
  "name": "Accessibility Rules",
  "description": "WCAG 2.1 AA compliance rules for accessible design",
  "category": "accessibility",
  "severity": "error",
  "rules": [
    {
      "id": "images-have-alt",
      "name": "Images Must Have Alt Text",
      "description": "All img elements must have meaningful alt text or be marked decorative",
      "severity": "error",
      "wcag": "1.1.1",
      "validation": {
        "type": "attribute-required",
        "element": "img",
        "attribute": "alt",
        "allowEmpty": true,
        "emptyMeansDecorative": true
      }
    },
    {
      "id": "buttons-have-text",
      "name": "Buttons Must Have Accessible Names",
      "description": "Button elements must have visible text or aria-label",
      "severity": "error",
      "wcag": "4.1.2",
      "validation": {
        "type": "accessible-name",
        "elements": ["button", "[role=button]"],
        "sources": ["text content", "aria-label", "aria-labelledby"]
      }
    },
    {
      "id": "form-labels",
      "name": "Form Inputs Must Have Labels",
      "description": "All form inputs must be associated with a label",
      "severity": "error",
      "wcag": "1.3.1",
      "validation": {
        "type": "label-association",
        "elements": ["input", "select", "textarea"],
        "methods": ["for/id", "aria-labelledby", "aria-label", "wrapper"]
      }
    },
    {
      "id": "focus-visible",
      "name": "Focus Must Be Visible",
      "description": "Interactive elements must have visible focus indicators",
      "severity": "error",
      "wcag": "2.4.7",
      "validation": {
        "type": "focus-style",
        "minContrastRatio": 3.0,
        "forbiddenPatterns": ["outline: none", "outline: 0", ":focus { outline: none }"]
      }
    },
    {
      "id": "color-not-only",
      "name": "Color Not Only Indicator",
      "description": "Information must not be conveyed by color alone",
      "severity": "warning",
      "wcag": "1.4.1",
      "guidelines": [
        "Error states need icon + color + text",
        "Links in text need underline or other indicator",
        "Status indicators need icon or pattern"
      ]
    },
    {
      "id": "touch-target-size",
      "name": "Minimum Touch Target Size",
      "description": "Interactive elements must be at least 44x44 CSS pixels",
      "severity": "warning",
      "wcag": "2.5.5",
      "validation": {
        "type": "size-check",
        "minWidth": 44,
        "minHeight": 44,
        "elements": ["button", "a", "[role=button]", "input[type=checkbox]", "input[type=radio]"]
      }
    },
    {
      "id": "keyboard-navigation",
      "name": "Keyboard Navigation",
      "description": "All functionality must be accessible via keyboard",
      "severity": "error",
      "wcag": "2.1.1",
      "validation": {
        "type": "keyboard-accessible",
        "requirements": [
          "All interactive elements focusable",
          "No keyboard traps",
          "Logical tab order",
          "Skip links for navigation"
        ]
      }
    }
  ],
  "compliance": {
    "level": "AA",
    "standards": ["WCAG 2.1"],
    "testingTools": [
      "axe-core",
      "pa11y",
      "lighthouse"
    ]
  }
}