---
phase: 05-search
plan: 02
type: execute
wave: 1
depends_on: []
files_modified:
  - src/lib/utils/filterEntries.ts
  - src/lib/utils/highlightText.ts
autonomous: true

must_haves:
  truths:
    - "Entries can be filtered by text search (title + content)"
    - "Entries can be filtered by tag (AND logic for multiple tags)"
    - "Entries can be filtered by entry type (task/thought)"
    - "Entries can be filtered by date range"
    - "Matching text can be highlighted in search results"
  artifacts:
    - path: "src/lib/utils/filterEntries.ts"
      provides: "Pure function to filter entries by SearchFilters"
      exports: ["filterEntries"]
      min_lines: 30
    - path: "src/lib/utils/highlightText.ts"
      provides: "Function to wrap matching text in mark tags"
      exports: ["highlightText"]
      min_lines: 15
  key_links:
    - from: "src/lib/utils/filterEntries.ts"
      to: "SearchFilters type"
      via: "import"
      pattern: "import.*SearchFilters.*from.*search"
    - from: "src/lib/utils/highlightText.ts"
      to: "mark element"
      via: "string replacement"
      pattern: "<mark.*class=.*font-bold"
---

<objective>
Create the filtering logic and text highlighting utilities.

Purpose: Implement pure functions that filter entries based on SearchFilters criteria and highlight matching text. These are decoupled from UI components for testability.
Output: filterEntries.ts and highlightText.ts utilities ready for use in the integrated search view.
</objective>

<execution_context>
@/home/tho/.claude/get-shit-done/workflows/execute-plan.md
@/home/tho/.claude/get-shit-done/templates/summary.md
</execution_context>

<context>
@.planning/PROJECT.md
@.planning/ROADMAP.md
@.planning/STATE.md
@.planning/phases/05-search/05-CONTEXT.md
@.planning/phases/05-search/05-RESEARCH.md
@src/lib/server/db/schema.ts
</context>

<tasks>

<task type="auto">
  <name>Task 1: Create filterEntries utility function</name>
  <files>src/lib/utils/filterEntries.ts</files>
  <action>
Create filterEntries.ts with a pure function that filters entries:

```typescript
import type { SearchFilters } from '$lib/types/search';
import type { Entry, Tag } from '$lib/server/db/schema';

interface EntryWithTags extends Entry {
  tags: Tag[];
}

export function filterEntries(
  entries: EntryWithTags[],
  filters: SearchFilters
): EntryWithTags[] {
  let result = entries;

  // Text search (title + content) - minimum 2 characters
  if (filters.query.length >= 2) {
    const query = filters.query.toLowerCase();
    result = result.filter(e =>
      (e.title?.toLowerCase().includes(query)) ||
      e.content.toLowerCase().includes(query)
    );
  }

  // Tag filter - AND logic (must have ALL selected tags)
  if (filters.tags.length > 0) {
    result = result.filter(e =>
      filters.tags.every(tagName =>
        e.tags.some(t => t.name.toLowerCase() === tagName.toLowerCase())
      )
    );
  }

  // Type filter
  if (filters.type !== 'all') {
    result = result.filter(e => e.type === filters.type);
  }

  // Date range filter (using createdAt)
  if (filters.dateRange.start) {
    result = result.filter(e => e.createdAt >= filters.dateRange.start!);
  }
  if (filters.dateRange.end) {
    // Include the end date by comparing to end of day
    const endOfDay = filters.dateRange.end + 'T23:59:59';
    result = result.filter(e => e.createdAt <= endOfDay);
  }

  return result;
}
```

Implementation notes:
- Case-insensitive text search (lowercase comparison)
- Case-insensitive tag matching (tags stored with original case but matched insensitively per 04-01 decision)
- AND logic for tags (every selected tag must be present)
- Date comparison works with ISO strings (schema uses ISO format)
- End date is inclusive (compare to end of day)
  </action>
  <verify>TypeScript compiles: `npx tsc --noEmit`</verify>
  <done>filterEntries function filters entries by query, tags, type, and date range</done>
</task>

<task type="auto">
  <name>Task 2: Create highlightText utility function</name>
  <files>src/lib/utils/highlightText.ts</files>
  <action>
Create highlightText.ts for search result highlighting:

```typescript
/**
 * Wraps matching text in <mark> tags for highlighting.
 * Returns HTML string to be used with {@html} in Svelte.
 *
 * @param text - The text to search within
 * @param query - The search query to highlight
 * @returns HTML string with matches wrapped in <mark> tags
 */
export function highlightText(text: string, query: string): string {
  // Don't highlight if query is too short
  if (!query || query.length < 2) return escapeHtml(text);

  // Escape HTML in the original text first
  const escaped = escapeHtml(text);

  // Escape regex special characters in query
  const escapedQuery = query.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
  const regex = new RegExp(`(${escapedQuery})`, 'gi');

  // Wrap matches in <mark> with bold styling (no background per CONTEXT.md)
  return escaped.replace(regex, '<mark class="font-bold bg-transparent">$1</mark>');
}

/**
 * Escapes HTML special characters to prevent XSS.
 */
function escapeHtml(text: string): string {
  const map: Record<string, string> = {
    '&': '&amp;',
    '<': '&lt;',
    '>': '&gt;',
    '"': '&quot;',
    "'": '&#039;'
  };
  return text.replace(/[&<>"']/g, char => map[char]);
}
```

Security notes:
- Always escape HTML before highlighting to prevent XSS
- The escapeHtml function runs BEFORE regex replacement
- Result is safe to use with {@html} directive

Styling notes:
- Uses font-bold for emphasis (per CONTEXT.md: "bold, not background highlight")
- bg-transparent ensures no background color on <mark>
  </action>
  <verify>TypeScript compiles: `npx tsc --noEmit`</verify>
  <done>highlightText function wraps matching text in styled mark tags with XSS protection</done>
</task>

</tasks>

<verification>
- `npm run check` passes
- filterEntries correctly filters by each criterion
- highlightText properly escapes HTML and highlights matches
</verification>

<success_criteria>
- filterEntries handles all filter types (query, tags, type, dateRange)
- Tag filtering uses AND logic (entry must have ALL selected tags)
- Text search is case-insensitive with 2-character minimum
- highlightText escapes HTML to prevent XSS
- Highlighted text uses bold styling without background
</success_criteria>

<output>
After completion, create `.planning/phases/05-search/05-02-SUMMARY.md`
</output>