/* components/file-upload/file-upload.css */

/**
 * File Upload Component
 * Full WCAG 2.2 AAA compliance with keyboard navigation
 * BEM methodology with accessibility focus
 */

 /* File Upload Design Tokens - Extension to existing design system */
/* Adds specific tokens for file upload component */

:root {
  /* File Upload specific colors */
  --ds-color-dropzone-bg: var(--ds-color-white);
  --ds-color-dropzone-bg-hover: var(--ds-color-surface-hover);
  --ds-color-dropzone-bg-active: var(--ds-color-accent-weak);
  --ds-color-dropzone-bg-disabled: var(--ds-color-surface-lowered);
  --ds-color-dropzone-border: var(--ds-color-border);
  --ds-color-dropzone-border-hover: var(--ds-color-accent);
  --ds-color-dropzone-border-active: var(--ds-color-accent);
  --ds-color-dropzone-border-disabled: var(--ds-color-border-weak);
  --ds-color-dropzone-text: var(--ds-color-text-weak);
  --ds-color-dropzone-text-disabled: var(--ds-color-text-weakest);
  
  /* File item colors */
  --ds-color-file-bg: var(--ds-color-white);
  --ds-color-file-bg-hover: var(--ds-color-surface-hover);
  --ds-color-file-border: var(--ds-color-border);
  --ds-color-file-text: var(--ds-color-text);
  --ds-color-file-text-secondary: var(--ds-color-text-weak);
  --ds-color-file-icon: var(--ds-color-text-weaker);
  
  /* Progress colors */
  --ds-color-progress-bg: var(--ds-color-border-weak);
  --ds-color-progress-fill: var(--ds-color-accent);
  --ds-color-progress-success: var(--ds-color-success);
  --ds-color-progress-error: var(--ds-color-danger);
  
  /* File Upload dimensions */
  --file-upload-dropzone-min-height: 10rem;
  --file-upload-dropzone-padding: var(--ds-space-xl);
  --file-upload-dropzone-gap: var(--ds-space-m);
  --file-upload-dropzone-border-width: 2px;
  --file-upload-dropzone-border-style: dashed;
  --file-upload-dropzone-border-radius: var(--ds-radius-l);
  
  --file-upload-icon-size: 2.5rem;
  --file-upload-icon-bg-size: 3rem;
  
  --file-upload-item-padding: var(--ds-space-m);
  --file-upload-item-gap: var(--ds-space-m);
  --file-upload-item-border-radius: var(--ds-radius-m);
  --file-upload-item-icon-size: 2.5rem;
  
  --file-upload-progress-height: 4px;
  --file-upload-progress-radius: var(--ds-radius-pill);
  
  /* Animations */
  --file-upload-transition: all var(--ds-duration-medium) var(--ds-ease-out);
  --file-upload-pulse-animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* Dark mode overrides */
[data-theme="dark"] {
  --ds-color-dropzone-bg: var(--ds-color-surface);
  --ds-color-dropzone-bg-hover: var(--ds-color-surface-raised);
  --ds-color-dropzone-bg-active: var(--ds-color-accent-weak);
  --ds-color-dropzone-bg-disabled: var(--ds-color-surface-lowered);
  
  --ds-color-file-bg: var(--ds-color-surface);
  --ds-color-file-bg-hover: var(--ds-color-surface-raised);
}

/* Pulse animation for drag active state */
@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

/* ========================================
   BASE FILE UPLOAD CONTAINER
   ======================================== */

.c-file-upload {
  position: relative;
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: var(--file-upload-dropzone-gap);
}

/* ========================================
   DROPZONE AREA
   ======================================== */

.c-file-upload__dropzone {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--file-upload-dropzone-gap);
  min-height: var(--file-upload-dropzone-min-height);
  padding: var(--file-upload-dropzone-padding);
  background: var(--ds-color-dropzone-bg);
  border: var(--file-upload-dropzone-border-width) var(--file-upload-dropzone-border-style) var(--ds-color-dropzone-border);
  border-radius: var(--file-upload-dropzone-border-radius);
  transition: var(--file-upload-transition);
  cursor: pointer;
}

/* Hover state */
.c-file-upload__dropzone:hover:not(.c-file-upload__dropzone--disabled) {
  background: var(--ds-color-dropzone-bg-hover);
  border-color: var(--ds-color-dropzone-border-hover);
}

/* Focus state for keyboard navigation */
.c-file-upload__dropzone:focus-within:not(.c-file-upload__dropzone--disabled) {
  outline: 2px solid var(--ds-focus-ring-color);
  outline-offset: 2px;
  border-color: var(--ds-color-dropzone-border-hover);
}

/* Drag active state */
.c-file-upload__dropzone--drag-active {
  background: var(--ds-color-dropzone-bg-active);
  border-color: var(--ds-color-dropzone-border-active);
  animation: var(--file-upload-pulse-animation);
}

/* Disabled state */
.c-file-upload__dropzone--disabled {
  background: var(--ds-color-dropzone-bg-disabled);
  border-color: var(--ds-color-dropzone-border-disabled);
  cursor: not-allowed;
  opacity: 0.6;
}

.c-file-upload__dropzone--disabled * {
  cursor: not-allowed;
}

/* Icon container */
.c-file-upload__dropzone-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: var(--file-upload-icon-bg-size);
  height: var(--file-upload-icon-bg-size);
  background: var(--ds-color-surface-raised);
  border: 1px solid var(--ds-color-border);
  border-radius: var(--ds-radius-m);
  color: var(--ds-color-accent);
  transition: var(--file-upload-transition);
}
.c-file-upload__dropzone-icon svg {
  stroke-width: 1;
}

.c-file-upload__dropzone:hover:not(.c-file-upload__dropzone--disabled) .c-file-upload__dropzone-icon {
  background: var(--ds-color-accent-weak);
  border-color: var(--ds-color-accent);
}

.c-file-upload__dropzone-icon svg {
  width: var(--file-upload-icon-size);
  height: var(--file-upload-icon-size);
}

/* Content area */
.c-file-upload__dropzone-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--ds-space-xs);
  text-align: center;
}

.c-file-upload__dropzone-text {
  display: flex;
  align-items: center;
  gap: var(--ds-space-s);
  flex-wrap: wrap;
  justify-content: center;
}

.c-file-upload__dropzone-hint {
  font-size: var(--ds-font-size-s);
  color: var(--ds-color-dropzone-text);
  margin: 0;
}

/* Hidden file input */
.c-file-upload__input {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Upload button link style */
.c-file-upload__button-link {
  background: none;
  border: none;
  padding: 0;
  color: var(--ds-color-accent);
  text-decoration: underline;
  text-underline-offset: 2px;
  text-decoration-color: transparent;
  cursor: pointer;
  font-weight: var(--ds-font-weight-medium);
  transition: var(--file-upload-transition);
}

.c-file-upload__button-link:hover:not(:disabled) {
  text-decoration-color: currentColor;
  color: var(--ds-color-accent-strong);
}

.c-file-upload__button-link:focus-visible {
  outline: 2px solid var(--ds-focus-ring-color);
  outline-offset: 2px;
  border-radius: var(--ds-radius-s);
}

.c-file-upload__button-link:disabled {
  color: var(--ds-color-text-weakest);
  cursor: not-allowed;
}

/* Drag text */
.c-file-upload__drag-text {
  color: var(--ds-color-text-weak);
  font-size: var(--ds-font-size-m);
}

/* ========================================
   FILES LIST
   ======================================== */

.c-file-upload__list {
  display: flex;
  flex-direction: column;
  gap: var(--ds-space-s);
  margin: 0;
  padding: 0;
  list-style: none;
}

/* ========================================
   FILE ITEM
   ======================================== */

.c-file-upload__item {
  position: relative;
  display: flex;
  align-items: center;
  gap: var(--file-upload-item-gap);
  padding: var(--file-upload-item-padding);
  background: var(--ds-color-file-bg);
  border: 1px solid var(--ds-color-file-border);
  border-radius: var(--file-upload-item-border-radius);
  transition: var(--file-upload-transition);
}

.c-file-upload__item:hover {
  background: var(--ds-color-file-bg-hover);
}

/* File icon */
.c-file-upload__item-icon {
  flex-shrink: 0;
  width: var(--file-upload-item-icon-size);
  height: var(--file-upload-item-icon-size);
  color: var(--ds-color-file-icon);
  stroke-width: 1;
}

/* File info */
.c-file-upload__item-info {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: var(--ds-space-xs);
}

.c-file-upload__item-name {
  font-size: var(--ds-font-size-m);
  font-weight: var(--ds-font-weight-medium);
  color: var(--ds-color-file-text);
  margin: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.c-file-upload__item-details {
  display: flex;
  align-items: center;
  gap: var(--ds-space-s);
  font-size: var(--ds-font-size-s);
  color: var(--ds-color-file-text-secondary);
}

.c-file-upload__item-size {
  white-space: nowrap;
}

.c-file-upload__item-separator {
  width: 1px;
  height: 12px;
  background: var(--ds-color-border);
  border: none;
}

/* File status */
.c-file-upload__item-status {
  display: flex;
  align-items: center;
  gap: var(--ds-space-xs);
  font-size: var(--ds-font-size-s);
  font-weight: var(--ds-font-weight-medium);
  padding: var(--ds-space-xs) var(--ds-space-s);
  border-radius: var(--ds-radius-s);
  transition: var(--file-upload-transition);
}

.c-file-upload__item-status--uploading {
  color: var(--ds-color-accent);
  background: rgba(var(--ds-color-accent-rgb), 0.08);
}

.c-file-upload__item-status--success {
  color: var(--ds-color-status-success);
  background: var(--ds-color-status-success-weak);
}

.c-file-upload__item-status--warning {
  color: var(--ds-color-text-warning);
  background: var(--ds-color-status-warning-weak);
}

.c-file-upload__item-status--error {
  color: var(--ds-color-status-danger);
  background: var(--ds-color-status-danger-weak);
}

.c-file-upload__item-status svg {
  width: 1rem;
  height: 1rem;
  flex-shrink: 0;
}

/* Progress bar container */
.c-file-upload__item-progress {
  position: relative;
  width: 100%;
  height: var(--file-upload-progress-height);
  background: var(--ds-color-surface-lowered);
  border-radius: var(--file-upload-progress-radius);
  overflow: hidden;
  margin-top: var(--ds-space-xs);
}

/* Progress bar fill */
.c-file-upload__item-progress-fill {
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  background: var(--ds-color-accent);
  border-radius: var(--file-upload-progress-radius);
  transition: width var(--ds-duration-medium) var(--ds-ease-out), background-color var(--ds-duration-fast) var(--ds-ease-out);
}

/* Progress bar color based on status */
.c-file-upload__item-progress--uploading .c-file-upload__item-progress-fill {
  background: var(--ds-color-accent);
}

.c-file-upload__item-progress--success .c-file-upload__item-progress-fill {
  background: var(--ds-color-status-success);
}

.c-file-upload__item-progress--warning .c-file-upload__item-progress-fill {
  background: var(--ds-color-status-warning);
}

.c-file-upload__item-progress--error .c-file-upload__item-progress-fill {
  background: var(--ds-color-status-danger);
}

/* Progress fill overlay (for alternative style) */
.c-file-upload__item--progress-overlay {
  position: relative;
  overflow: hidden;
}

.c-file-upload__item--progress-overlay::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  width: var(--progress, 0%);
  background: var(--ds-color-accent-weak);
  z-index: 0;
  transition: width var(--ds-duration-medium) var(--ds-ease-out);
}

.c-file-upload__item--progress-overlay > * {
  position: relative;
  z-index: 1;
}

/* Actions */
.c-file-upload__item-actions {
  display: flex;
  align-items: center;
  gap: var(--ds-space-xs);
}

/* Delete button */
.c-file-upload__item-delete {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--ds-space-xs);
  background: transparent;
  border: none;
  border-radius: var(--ds-radius-s);
  color: var(--ds-color-text-weaker);
  cursor: pointer;
  transition: var(--file-upload-transition);
}

.c-file-upload__item-delete:hover {
  background: var(--ds-color-surface-hover);
  color: var(--ds-color-danger);
}

.c-file-upload__item-delete:focus-visible {
  outline: 2px solid var(--ds-focus-ring-color);
  outline-offset: 2px;
}

.c-file-upload__item-delete svg {
  width: 1.25rem;
  height: 1.25rem;
}

/* Retry button */
.c-file-upload__item-retry {
  display: inline-flex;
  align-items: center;
  gap: var(--ds-space-xs);
  padding: var(--ds-space-xs) var(--ds-space-s);
  background: var(--ds-color-status-danger-weak);
  border: 1px solid var(--ds-color-border-danger);
  color: var(--ds-color-status-danger);
  font-size: var(--ds-font-size-s);
  font-weight: var(--ds-font-weight-medium);
  border-radius: var(--ds-radius-s);
  cursor: pointer;
  transition: var(--file-upload-transition);
}

.c-file-upload__item-retry:hover:not(:disabled) {
  background: var(--ds-color-status-danger);
  color: white;
  border-color: var(--ds-color-status-danger);
}

.c-file-upload__item-retry:focus-visible {
  outline: 2px solid var(--ds-focus-ring-color);
  outline-offset: 2px;
}

.c-file-upload__item-retry:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ========================================
   RESPONSIVE DESIGN
   ======================================== */

@media (max-width: 768px) {
  .c-file-upload__dropzone {
    padding: var(--ds-space-l);
  }
  
  .c-file-upload__drag-text {
    display: none;
  }
  
  .c-file-upload__item {
    padding: var(--ds-space-s);
  }
  
  .c-file-upload__item-icon {
    width: 2rem;
    height: 2rem;
  }
}

/* ========================================
   ACCESSIBILITY ENHANCEMENTS
   ======================================== */

/* High contrast mode support */
@media (prefers-contrast: high) {
  .c-file-upload__dropzone {
    border-width: 3px;
  }
  
  .c-file-upload__item {
    border-width: 2px;
  }
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
  .c-file-upload__dropzone,
  .c-file-upload__item,
  .c-file-upload__item-progress-fill {
    transition: none;
  }
  
  .c-file-upload__dropzone--drag-active {
    animation: none;
  }
}

/* Screen reader only text */
.c-file-upload__sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}