-- Migration 005: Add full-text search using FTS5
--
-- Creates FTS5 virtual table for full-text search of notes.
-- Since note content is stored in external files (not in the database),
-- the FTS index must be maintained by application code, not SQL triggers.
--
-- Requirements:
-- - SQLite compiled with FTS5 support
-- - Application code handles index synchronization
--
-- Features:
-- - Full-text search on note content
-- - Porter stemming for better English search results
-- - Unicode normalization for international characters
-- - rowid matches notes.id for efficient lookups

-- Create FTS5 virtual table for note search
-- Using porter stemmer for better English search results
-- Unicode61 tokenizer for international character support
-- Note: slug is UNINDEXED (not searchable, just for result display)
CREATE VIRTUAL TABLE IF NOT EXISTS notes_fts USING fts5(
    slug UNINDEXED,      -- Slug for result linking (not searchable)
    title,               -- First line of note (searchable, high weight)
    content,             -- Full markdown content (searchable)
    tokenize='porter unicode61'
);

-- Create delete trigger to remove from FTS when note is deleted
-- This is the only trigger we can use since deletion doesn't require file access
CREATE TRIGGER IF NOT EXISTS notes_fts_delete
AFTER DELETE ON notes
BEGIN
    DELETE FROM notes_fts WHERE rowid = OLD.id;
END;

-- Note: INSERT and UPDATE triggers cannot be used because they would need
-- to read content from external files, which SQLite triggers cannot do.
-- The application code in starpunk/notes.py handles FTS updates for
-- create and update operations.

-- Initial index population:
-- After this migration runs, the FTS index must be populated with existing notes.
-- This happens automatically on application startup via starpunk/search.py:rebuild_fts_index()
-- or can be triggered manually if needed.