InstallSelector.astro

---
import { codeToTokens } from 'shiki';

interface InstallOption {
  label: string;
  command: string;
}

interface Props {
  options: InstallOption[];
  defaultIndex?: number;
}

const { options, defaultIndex = 0 } = Astro.props;

/**
 * Highlights a shell command using Shiki and returns inline HTML.
 */
async function highlightCommand(cmd: string): Promise<string> {
  const { tokens } = await codeToTokens(cmd, {
    lang: 'bash',
    theme: 'github-dark',
  });
  
  // Convert tokens to inline HTML spans (single line command)
  return tokens[0]
    .map(token => {
      const escaped = token.content
        .replace(/&/g, '&amp;')
        .replace(/</g, '&lt;')
        .replace(/>/g, '&gt;');
      return `<span style="color: ${token.color}">${escaped}</span>`;
    })
    .join('');
}

// Pre-highlight all options server-side for client-side switching
const highlightedOptions = await Promise.all(
  options.map(async (opt) => ({
    label: opt.label,
    command: opt.command,
    highlighted: await highlightCommand(opt.command),
  }))
);

const defaultOption = highlightedOptions[defaultIndex];
---

<div class="install-selector">
  <div class="install-box">
    <button class="dropdown-trigger" aria-expanded="false" aria-haspopup="listbox">
      <span class="dropdown-label">{defaultOption.label}</span>
      <svg class="chevron" xmlns="http://www.w3.org/2000/svg" width="12" height="12" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
        <path d="m6 9 6 6 6-6"/>
      </svg>
    </button>
    
    <div class="command-area" style={{marginTop: 0}}>
      <code class="command-text" style={{backgroundColor: 'transparent'}} data-command={defaultOption.command} set:html={defaultOption.highlighted} />
      <button class="copy-btn" data-command={defaultOption.command} aria-label="Copy to clipboard">
        <svg class="copy-icon" xmlns="http://www.w3.org/2000/svg" width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
          <rect width="14" height="14" x="8" y="8" rx="2" ry="2"/>
          <path d="M4 16c-1.1 0-2-.9-2-2V4c0-1.1.9-2 2-2h10c1.1 0 2 .9 2 2"/>
        </svg>
        <svg class="check-icon" xmlns="http://www.w3.org/2000/svg" width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
          <path d="M20 6 9 17l-5-5"/>
        </svg>
      </button>
    </div>
    
    <ul class="dropdown-menu" role="listbox" aria-label="Installation method">
      {highlightedOptions.map((opt, index) => (
        <li>
          <button 
            class={`dropdown-option ${index === defaultIndex ? 'selected' : ''}`}
            data-label={opt.label}
            data-command={opt.command}
            data-highlighted={opt.highlighted}
            role="option"
            aria-selected={index === defaultIndex ? 'true' : 'false'}
          >
            {opt.label}
          </button>
        </li>
      ))}
    </ul>
  </div>
</div>

<style>
  .install-selector {
    position: relative;
    width: fit-content;
  }

  /* Unified container with shared border */
  .install-box {
    display: flex;
    align-items: stretch;
    position: relative;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 9999px;
  }

  .dropdown-trigger {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(255, 255, 255, 0.04);
    border: none;
    border-radius: 9999px 0 0 9999px;
    padding: 0.6rem 1rem;
    font-family: inherit;
    font-size: 0.9rem;
    font-weight: 500;
    color: rgba(255, 255, 255, 0.7);
    cursor: pointer;
    transition: background-color 0.2s ease;
    white-space: nowrap;
    position: relative;
    z-index: 1;
  }

  .dropdown-trigger:hover {
    background: rgba(255, 255, 255, 0.08);
  }

  .chevron {
    transition: transform 0.2s ease;
    opacity: 0.6;
  }

  .install-box.open .chevron {
    transform: rotate(180deg);
  }

  .command-area {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background: transparent;
    border: none;
    padding: 0.6rem 1rem;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.875rem;
    line-height: 1;
  }

  .command-text {
    white-space: nowrap;
    background: transparent;
    min-width: 47ch; /* Fixed width for longest command (curl) */
  }

  /* Remove any background from Shiki-generated spans */
  .command-text :global(span) {
    background: transparent !important;
  }

  .copy-btn {
    background: none;
    border: none;
    color: rgba(255, 255, 255, 0.4);
    cursor: pointer;
    padding: 0;
    transition: color 0.2s ease;
    flex-shrink: 0;
    width: 16px;
    height: 16px;
    display: grid;
    place-items: center;
  }

  .copy-btn:hover {
    color: #fff;
  }

  .copy-btn .copy-icon,
  .copy-btn .check-icon {
    grid-area: 1 / 1;
    pointer-events: none;
    transition: opacity 0.15s ease;
  }

  .copy-btn .check-icon {
    opacity: 0;
    color: #22c55e;
    transform: translateY(-6px);
  }

  .copy-btn.copied .copy-icon {
    opacity: 0;
  }

  .copy-btn.copied .check-icon {
    opacity: 1;
  }

  .dropdown-menu {
    position: absolute;
    top: 90%;
    left: 0;
    background: #1a1a1f;
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 0.75rem;
    padding: 0.5rem !important;
    list-style: none;
    margin: 0;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: all 0.2s ease;
    z-index: 100;
    min-width: 120px;
  }

  .install-box.open .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .dropdown-menu li {
    margin: 0;
    padding: 0;
  }

  .dropdown-option {
    width: 100%;
    margin-bottom: 0 !important;
    display: block;
    padding: 0.5rem 0.75rem;
    background: none;
    border: none;
    border-radius: 0.5rem;
    font-family: inherit;
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.8);
    cursor: pointer;
    text-align: left;
    transition: background-color 0.15s ease;
  }

  .dropdown-option:hover {
    background: rgba(255, 255, 255, 0.08);
  }

  .dropdown-option.selected {
    background: rgba(255, 255, 255, 0.1);
    font-weight: 500;
  }

  .dropdown-option:focus {
    outline: none;
    background: rgba(255, 255, 255, 0.12);
  }

  .dropdown-option:focus-visible {
    outline: 2px solid rgba(255, 255, 255, 0.4);
    outline-offset: -2px;
  }
</style>

<script is:inline>
  (function() {
    function initInstallSelector() {
      document.querySelectorAll('.install-selector').forEach(function(selector) {
        const installBox = selector.querySelector('.install-box');
        const trigger = selector.querySelector('.dropdown-trigger');
        const label = selector.querySelector('.dropdown-label');
        const commandText = selector.querySelector('.command-text');
        const copyBtn = selector.querySelector('.copy-btn');
        const options = selector.querySelectorAll('.dropdown-option');
        const optionsArray = Array.from(options);

        if (!trigger || !installBox) return;

        /**
         * Selects an option: updates UI, closes dropdown, returns focus to trigger.
         */
        function selectOption(option) {
          const newLabel = option.getAttribute('data-label');
          const newCommand = option.getAttribute('data-command');
          const newHighlighted = option.getAttribute('data-highlighted');
          
          if (label && newLabel) label.textContent = newLabel;
          if (commandText && newHighlighted) {
            commandText.innerHTML = newHighlighted;
          }
          if (commandText && newCommand) {
            commandText.setAttribute('data-command', newCommand);
          }
          if (copyBtn && newCommand) {
            copyBtn.setAttribute('data-command', newCommand);
          }
          
          // Update selected state
          options.forEach(function(opt) {
            opt.classList.remove('selected');
            opt.setAttribute('aria-selected', 'false');
          });
          option.classList.add('selected');
          option.setAttribute('aria-selected', 'true');
          
          // Close dropdown and return focus
          installBox.classList.remove('open');
          trigger.setAttribute('aria-expanded', 'false');
          trigger.focus();
        }

        /**
         * Opens the dropdown and focuses the selected or first option.
         */
        function openDropdown() {
          // Close all other dropdowns first
          document.querySelectorAll('.install-box.open').forEach(function(box) {
            if (box !== installBox) box.classList.remove('open');
          });
          
          installBox.classList.add('open');
          trigger.setAttribute('aria-expanded', 'true');
          
          // Focus the currently selected option, or first option
          const selectedOption = selector.querySelector('.dropdown-option.selected') || options[0];
          if (selectedOption) selectedOption.focus();
        }

        /**
         * Closes the dropdown and returns focus to trigger.
         */
        function closeDropdown() {
          installBox.classList.remove('open');
          trigger.setAttribute('aria-expanded', 'false');
          trigger.focus();
        }

        // Toggle dropdown on click
        trigger.addEventListener('click', function(e) {
          e.stopPropagation();
          const isOpen = installBox.classList.contains('open');
          
          if (isOpen) {
            closeDropdown();
          } else {
            openDropdown();
          }
        });

        // Keyboard navigation on trigger
        trigger.addEventListener('keydown', function(e) {
          const isOpen = installBox.classList.contains('open');
          
          if (e.key === 'ArrowDown' || e.key === 'ArrowUp') {
            e.preventDefault();
            if (!isOpen) {
              openDropdown();
            } else {
              // Focus first or last option based on direction
              const targetOption = e.key === 'ArrowDown' ? options[0] : options[options.length - 1];
              if (targetOption) targetOption.focus();
            }
          }
          
          if (e.key === 'Enter' || e.key === ' ') {
            e.preventDefault();
            if (!isOpen) {
              openDropdown();
            }
          }
          
          if (e.key === 'Home' && isOpen) {
            e.preventDefault();
            if (options[0]) options[0].focus();
          }
          
          if (e.key === 'End' && isOpen) {
            e.preventDefault();
            if (options[options.length - 1]) options[options.length - 1].focus();
          }
        });

        // Handle option click and keyboard navigation
        options.forEach(function(option, index) {
          option.addEventListener('click', function() {
            selectOption(option);
          });
          
          option.addEventListener('keydown', function(e) {
            if (e.key === 'ArrowDown') {
              e.preventDefault();
              const nextIndex = index < optionsArray.length - 1 ? index + 1 : 0;
              optionsArray[nextIndex].focus();
            }
            
            if (e.key === 'ArrowUp') {
              e.preventDefault();
              const prevIndex = index > 0 ? index - 1 : optionsArray.length - 1;
              optionsArray[prevIndex].focus();
            }
            
            if (e.key === 'Home') {
              e.preventDefault();
              options[0].focus();
            }
            
            if (e.key === 'End') {
              e.preventDefault();
              options[options.length - 1].focus();
            }
            
            if (e.key === 'Enter' || e.key === ' ') {
              e.preventDefault();
              selectOption(option);
            }
            
            if (e.key === 'Escape') {
              e.preventDefault();
              closeDropdown();
            }
            
            if (e.key === 'Tab') {
              // Close dropdown when tabbing away
              closeDropdown();
            }
          });
        });

        // Copy functionality
        if (copyBtn) {
          copyBtn.addEventListener('click', async function() {
            const command = copyBtn.getAttribute('data-command');
            if (command) {
              await navigator.clipboard.writeText(command);
              copyBtn.classList.add('copied');
              setTimeout(function() { copyBtn.classList.remove('copied'); }, 2000);
            }
          });
        }
      });

      // Close dropdown when clicking outside
      document.addEventListener('click', function(e) {
        if (!e.target.closest('.install-selector')) {
          document.querySelectorAll('.install-box.open').forEach(function(box) {
            box.classList.remove('open');
            const trigger = box.querySelector('.dropdown-trigger');
            if (trigger) trigger.setAttribute('aria-expanded', 'false');
          });
        }
      });

      // Close on escape (global handler for when focus is elsewhere)
      document.addEventListener('keydown', function(e) {
        if (e.key === 'Escape') {
          document.querySelectorAll('.install-box.open').forEach(function(box) {
            box.classList.remove('open');
            const trigger = box.querySelector('.dropdown-trigger');
            if (trigger) {
              trigger.setAttribute('aria-expanded', 'false');
              trigger.focus();
            }
          });
        }
      });
    }

    // Run when DOM is ready
    if (document.readyState === 'loading') {
      document.addEventListener('DOMContentLoaded', initInstallSelector);
    } else {
      initInstallSelector();
    }

    // Re-run after Astro page transitions
    document.addEventListener('astro:after-swap', initInstallSelector);
  })();
</script>