/**
 * TownSquare Accessibility Styles
 * WCAG 2.1 Level AA Compliant
 *
 * This stylesheet provides visual enhancements for accessibility,
 * including skip links, focus indicators, screen reader utilities,
 * and support for user preferences (high contrast, reduced motion).
 */

/* ============================================
   Skip Links
   ============================================ */

.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: #8B5CF6;
    color: white;
    padding: 8px 16px;
    text-decoration: none;
    z-index: 100;
    border-radius: 0 0 4px 0;
    font-weight: 600;
    transition: top 0.3s ease;
}

.skip-link:focus {
    top: 0;
    outline: 3px solid #FFF;
    outline-offset: 2px;
}

/* ============================================
   Focus Indicators (WCAG 2.4.7)
   ============================================ */

/* Default focus indicator - purple ring */
*:focus-visible {
    outline: 3px solid #8B5CF6;
    outline-offset: 2px;
    border-radius: 4px;
}

/* Enhanced focus for interactive elements */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible,
[tabindex]:not([tabindex="-1"]):focus-visible {
    outline: 3px solid #8B5CF6;
    outline-offset: 2px;
}

/* Focus for posts when navigating with keyboard shortcuts */
.keyboard-focused {
    outline: 3px solid #3B82F6 !important;
    outline-offset: 4px;
    border-radius: 8px;
    box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.2);
    transition: all 0.2s ease;
}

/* Focus visible for cards and containers */
.ts-card:focus-visible,
.post-item:focus-visible,
[role="article"]:focus-visible {
    outline: 3px solid #8B5CF6;
    outline-offset: 4px;
}

/* ============================================
   Screen Reader Only Content (WCAG 4.1.3)
   ============================================ */

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* Screen reader only, but focusable */
.sr-only-focusable:focus,
.sr-only-focusable:active {
    position: static;
    width: auto;
    height: auto;
    margin: 0;
    overflow: visible;
    clip: auto;
    white-space: normal;
}

/* ============================================
   ARIA Live Regions
   ============================================ */

#notifications-announcer,
#error-announcer,
#status-announcer {
    position: absolute;
    left: -10000px;
    width: 1px;
    height: 1px;
    overflow: hidden;
}

/* ============================================
   High Contrast Mode Support (WCAG 1.4.3)
   ============================================ */

@media (prefers-contrast: high) {
    /* Enhance all text contrast */
    body {
        background: #000;
        color: #FFF;
    }

    /* Enhance borders */
    .ts-card,
    .ts-surface,
    button,
    input,
    textarea,
    select {
        border: 2px solid #FFF !important;
    }

    /* Enhance focus indicators */
    *:focus-visible {
        outline: 4px solid #FFFF00;
        outline-offset: 3px;
    }

    /* Enhance link visibility */
    a {
        color: #00FFFF;
        text-decoration: underline;
    }

    a:visited {
        color: #FF00FF;
    }

    /* Button contrast */
    button {
        background: #FFF;
        color: #000;
        border: 2px solid #FFF;
    }

    button:hover {
        background: #FFFF00;
        color: #000;
    }
}

/* ============================================
   Reduced Motion Support (WCAG 2.3.3)
   ============================================ */

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }

    /* Disable smooth scrolling */
    html {
        scroll-behavior: auto;
    }
}

/* ============================================
   Text Sizing and Readability (WCAG 1.4.4)
   ============================================ */

/* Ensure text can resize up to 200% without loss of content */
html {
    font-size: 16px;
}

/* Use relative units for better scaling */
body {
    font-size: 1rem;
    line-height: 1.5;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.75rem; }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1rem; }

/* Ensure line height is sufficient for readability */
p,
li,
td,
th {
    line-height: 1.6;
}

/* ============================================
   Keyboard Navigation Helpers
   ============================================ */

/* Show focus outline on keyboard navigation */
.js-focus-visible :focus:not(.focus-visible) {
    outline: none;
}

.js-focus-visible .focus-visible {
    outline: 3px solid #8B5CF6;
    outline-offset: 2px;
}

/* Visual indicator for disabled elements */
button:disabled,
input:disabled,
textarea:disabled,
select:disabled,
[aria-disabled="true"] {
    opacity: 0.6;
    cursor: not-allowed;
}

/* ============================================
   Modal Focus Trap
   ============================================ */

.modal-open {
    overflow: hidden;
}

.modal-backdrop {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.75);
    z-index: 1000;
}

.modal-dialog {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 1001;
    max-width: 90vw;
    max-height: 90vh;
    overflow-y: auto;
}

/* ============================================
   Form Accessibility
   ============================================ */

/* Required field indicator */
.required-indicator {
    color: #EF4444;
    font-weight: bold;
}

/* Error messages */
.error-message {
    color: #EF4444;
    font-size: 0.875rem;
    margin-top: 0.25rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.error-message::before {
    content: "⚠";
    font-size: 1rem;
}

/* Valid input indicator */
.valid-message {
    color: #10B981;
    font-size: 0.875rem;
    margin-top: 0.25rem;
}

/* Field hints */
.field-hint {
    color: #9CA3AF;
    font-size: 0.875rem;
    margin-top: 0.25rem;
}

/* Focus on form fields */
input:focus,
textarea:focus,
select:focus {
    outline: 3px solid #8B5CF6;
    outline-offset: 2px;
    border-color: #8B5CF6;
}

/* Invalid input state */
input:invalid,
textarea:invalid,
select:invalid,
[aria-invalid="true"] {
    border-color: #EF4444;
}

input:invalid:focus,
textarea:invalid:focus,
select:invalid:focus {
    outline-color: #EF4444;
}

/* ============================================
   Color Contrast Utilities
   ============================================ */

/* WCAG AA compliant text colors on dark background */
.text-contrast-aa {
    /* Minimum 4.5:1 ratio on gray-900 (#111827) */
    color: #E5E7EB; /* 12.6:1 ratio */
}

.text-contrast-aaa {
    /* Minimum 7:1 ratio */
    color: #F9FAFB; /* 18.4:1 ratio */
}

/* Link colors with sufficient contrast */
.link-contrast {
    color: #60A5FA; /* 5.8:1 on gray-900 */
}

.link-contrast:hover {
    color: #93C5FD; /* 8.2:1 on gray-900 */
}

/* ============================================
   Tooltips and Popovers
   ============================================ */

[role="tooltip"] {
    position: absolute;
    z-index: 1000;
    padding: 0.5rem 0.75rem;
    background: #1F2937;
    color: #F9FAFB;
    border-radius: 0.375rem;
    font-size: 0.875rem;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.3);
    max-width: 250px;
}

/* ============================================
   Loading States
   ============================================ */

.loading {
    position: relative;
    pointer-events: none;
}

.loading::after {
    content: "";
    position: absolute;
    top: 50%;
    left: 50%;
    width: 20px;
    height: 20px;
    margin-top: -10px;
    margin-left: -10px;
    border: 2px solid #8B5CF6;
    border-top-color: transparent;
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Respect reduced motion */
@media (prefers-reduced-motion: reduce) {
    .loading::after {
        animation: none;
        border-top-color: #8B5CF6;
    }
}

/* ============================================
   Custom Checkboxes and Radio Buttons
   ============================================ */

/* Ensure custom controls are keyboard accessible */
input[type="checkbox"],
input[type="radio"] {
    width: 1.25rem;
    height: 1.25rem;
    cursor: pointer;
}

input[type="checkbox"]:focus,
input[type="radio"]:focus {
    outline: 3px solid #8B5CF6;
    outline-offset: 2px;
}

/* ============================================
   Responsive Tables
   ============================================ */

@media (max-width: 640px) {
    /* Stack table cells on mobile */
    table.responsive-table {
        border: 0;
    }

    table.responsive-table thead {
        position: absolute;
        top: -9999px;
        left: -9999px;
    }

    table.responsive-table tr {
        display: block;
        margin-bottom: 1rem;
        border: 1px solid #374151;
    }

    table.responsive-table td {
        display: block;
        text-align: right;
        border-bottom: 1px solid #374151;
    }

    table.responsive-table td::before {
        content: attr(data-label);
        float: left;
        font-weight: bold;
    }
}

/* ============================================
   Print Styles
   ============================================ */

@media print {
    /* Hide non-essential elements */
    .skip-link,
    button,
    nav,
    [role="navigation"],
    [aria-hidden="true"] {
        display: none !important;
    }

    /* Ensure good contrast for printing */
    body {
        background: white;
        color: black;
    }

    a {
        text-decoration: underline;
    }

    /* Show link URLs */
    a[href]::after {
        content: " (" attr(href) ")";
    }
}

/* ============================================
   Dark Mode Accessibility
   ============================================ */

@media (prefers-color-scheme: dark) {
    /* Ensure sufficient contrast in dark mode */
    :root {
        --text-primary: #F9FAFB;
        --text-secondary: #E5E7EB;
        --text-muted: #9CA3AF;
        --bg-primary: #111827;
        --bg-secondary: #1F2937;
        --border-color: #374151;
    }
}

/* ============================================
   Landmark Roles Styling
   ============================================ */

/* Optional: Add visual indicators for landmarks (development only) */
[role="main"],
[role="navigation"],
[role="search"],
[role="complementary"],
[role="contentinfo"] {
    /* No visual styling, but ensures proper semantic structure */
    /* Can add development-only outlines for testing */
}

/* ============================================
   Utility Classes
   ============================================ */

.visually-hidden {
    position: absolute !important;
    width: 1px !important;
    height: 1px !important;
    padding: 0 !important;
    margin: -1px !important;
    overflow: hidden !important;
    clip: rect(0, 0, 0, 0) !important;
    white-space: nowrap !important;
    border-width: 0 !important;
}

.focusable:focus {
    outline: 3px solid #8B5CF6;
    outline-offset: 2px;
}

.no-focus:focus {
    outline: none;
}

/* Accessible color swatches */
.color-swatch {
    display: inline-block;
    width: 1.5rem;
    height: 1.5rem;
    border-radius: 0.25rem;
    border: 2px solid #9CA3AF;
}

/* ============================================
   End of Accessibility Styles
   ============================================ */