navidocs/agent_7_code_changes.txt

================================================================================
AGENT 7 - THUMBNAIL GENERATION CODE CHANGES
File: /home/setup/navidocs/client/src/views/DocumentView.vue
================================================================================

CHANGE 1: Add State Variables (Insert after line ~380, after searchStats computed)
================================================================================

// Thumbnail cache and state for search results
const thumbnailCache = new Map() // pageNum -> dataURL
const thumbnailLoading = ref(new Set()) // Track which thumbnails are currently loading

================================================================================
CHANGE 2: Add Thumbnail Functions (Insert after makeTocEntriesClickable(), before renderPage())
================================================================================

/**
 * Generate thumbnail for a specific page
 * @param {number} pageNum - Page number to generate thumbnail for
 * @returns {Promise<string>} Data URL of the thumbnail image
 */
async function generateThumbnail(pageNum) {
  // Check cache first
  if (thumbnailCache.has(pageNum)) {
    return thumbnailCache.get(pageNum)
  }

  // Check if already loading
  if (thumbnailLoading.value.has(pageNum)) {
    // Wait for the thumbnail to be generated
    return new Promise((resolve) => {
      const checkInterval = setInterval(() => {
        if (thumbnailCache.has(pageNum)) {
          clearInterval(checkInterval)
          resolve(thumbnailCache.get(pageNum))
        }
      }, 100)
    })
  }

  // Mark as loading
  thumbnailLoading.value.add(pageNum)

  try {
    if (!pdfDoc) {
      throw new Error('PDF document not loaded')
    }

    const page = await pdfDoc.getPage(pageNum)

    // Use small scale for thumbnail (0.2 = 20% of original size)
    // This produces roughly 80x100px thumbnails for standard letter-sized pages
    const viewport = page.getViewport({ scale: 0.2 })

    // Create canvas for thumbnail rendering
    const canvas = document.createElement('canvas')
    const context = canvas.getContext('2d', { alpha: false })

    if (!context) {
      throw new Error('Failed to get canvas context for thumbnail')
    }

    canvas.width = viewport.width
    canvas.height = viewport.height

    // Render page to canvas
    await page.render({
      canvasContext: context,
      viewport: viewport
    }).promise

    // Convert canvas to data URL
    const dataURL = canvas.toDataURL('image/png', 0.8) // 0.8 quality for smaller file size

    // Cache the thumbnail
    thumbnailCache.set(pageNum, dataURL)

    return dataURL
  } catch (err) {
    console.error(`Failed to generate thumbnail for page ${pageNum}:`, err)
    // Return a placeholder or empty data URL
    return ''
  } finally {
    // Remove from loading set
    thumbnailLoading.value.delete(pageNum)
  }
}

/**
 * Check if a thumbnail is currently being generated
 * @param {number} pageNum - Page number to check
 * @returns {boolean} True if thumbnail is loading
 */
function isThumbnailLoading(pageNum) {
  return thumbnailLoading.value.has(pageNum)
}

/**
 * Get thumbnail for a page, generating if needed
 * @param {number} pageNum - Page number
 * @returns {Promise<string>} Data URL of thumbnail
 */
async function getThumbnail(pageNum) {
  return await generateThumbnail(pageNum)
}

/**
 * Clear thumbnail cache (useful when document changes)
 */
function clearThumbnailCache() {
  thumbnailCache.clear()
  thumbnailLoading.value.clear()
}

================================================================================
CHANGE 3: Update resetDocumentState() Function
================================================================================

Find the resetDocumentState() function and add this line at the beginning:

async function resetDocumentState() {
  clearImages()
  clearThumbnailCache() // ADD THIS LINE

  // ... rest of existing code
}

================================================================================
TEMPLATE EXAMPLE: Search Results with Thumbnails
================================================================================

<!-- Replace or enhance existing Jump List template -->
<div v-if="jumpListOpen && hitList.length > 0" class="absolute right-6 top-full mt-2 w-96 bg-dark-900/95 backdrop-blur-lg border border-white/10 rounded-lg p-3 shadow-2xl z-50">
  <div class="grid gap-2 max-h-96 overflow-y-auto">
    <button
      v-for="(hit, idx) in hitList.slice(0, 10)"
      :key="idx"
      @click="jumpToHit(idx)"
      class="text-left flex gap-3 px-3 py-2 bg-white/5 hover:bg-white/10 rounded transition-colors border border-white/10"
      :class="{ 'ring-2 ring-pink-400': idx === currentHitIndex }"
    >
      <!-- Thumbnail -->
      <div class="flex-shrink-0">
        <!-- Loading Placeholder -->
        <div
          v-if="isThumbnailLoading(hit.page)"
          class="w-20 h-25 bg-white/10 rounded flex items-center justify-center"
        >
          <div class="w-4 h-4 border-2 border-white/30 border-t-pink-400 rounded-full animate-spin"></div>
        </div>

        <!-- Thumbnail Image -->
        <img
          v-else
          :src="getThumbnail(hit.page)"
          :alt="`Page ${hit.page} thumbnail`"
          class="w-20 h-auto rounded shadow-md border border-white/20"
          loading="lazy"
        />
      </div>

      <!-- Match Info -->
      <div class="flex-1 min-w-0">
        <div class="flex items-center justify-between gap-2 mb-1">
          <span class="text-white/70 text-xs font-mono">Match {{ idx + 1 }}</span>
          <span class="text-white/50 text-xs">Page {{ hit.page }}</span>
        </div>
        <p class="text-white text-sm line-clamp-2">{{ hit.snippet }}</p>
      </div>
    </button>

    <div v-if="hitList.length > 10" class="text-white/50 text-xs text-center py-2">
      + {{ hitList.length - 10 }} more matches
    </div>
  </div>
</div>

================================================================================
CSS ADDITIONS (Add to <style> section if needed)
================================================================================

.thumbnail-container {
  width: 80px;
  min-width: 80px;
}

.thumbnail-loading {
  animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

================================================================================
USAGE NOTES
================================================================================

1. Thumbnails are cached after first generation
2. Multiple requests for same page wait for first to complete
3. Scale of 0.2 produces ~80x100px thumbnails
4. PNG quality of 0.8 balances size and quality
5. Call getThumbnail(pageNum) from template (returns Promise<string>)
6. Check isThumbnailLoading(pageNum) to show loading state
7. clearThumbnailCache() clears all cached thumbnails

================================================================================
INTEGRATION STATUS
================================================================================

✓ State variables defined
✓ Core functions implemented
✓ Caching logic complete
✓ Loading state management
✓ Error handling
✓ Cleanup integration
□ Template integration (Agent 8)
□ UI styling (Agent 8)
□ Testing (Agent 10)

================================================================================