-- Fix vector search timeout by adding document_id filtering and optimizing the query
-- This prevents searching across all documents and only searches within a specific document

-- Drop the old function (handle all possible signatures)
DROP FUNCTION IF EXISTS match_document_chunks(vector(1536), float, int);
DROP FUNCTION IF EXISTS match_document_chunks(vector(1536), float, int, text);

-- Create optimized function with document_id filtering
-- document_id is TEXT (varchar) in the actual schema
CREATE OR REPLACE FUNCTION match_document_chunks (
  query_embedding vector(1536),
  match_threshold float,
  match_count int,
  filter_document_id text DEFAULT NULL
)
RETURNS TABLE (
  id UUID,
  document_id TEXT,
  content text,
  metadata JSONB,
  chunk_index INT,
  similarity float
)
LANGUAGE sql STABLE
AS $$
  SELECT
    document_chunks.id,
    document_chunks.document_id,
    document_chunks.content,
    document_chunks.metadata,
    document_chunks.chunk_index,
    1 - (document_chunks.embedding <=> query_embedding) AS similarity
  FROM document_chunks
  WHERE document_chunks.embedding IS NOT NULL
    AND (filter_document_id IS NULL OR document_chunks.document_id = filter_document_id)
    AND 1 - (document_chunks.embedding <=> query_embedding) > match_threshold
  ORDER BY document_chunks.embedding <=> query_embedding
  LIMIT match_count;
$$;

-- Add comment explaining the optimization
COMMENT ON FUNCTION match_document_chunks IS 'Optimized vector search that filters by document_id first to prevent timeouts. Always pass filter_document_id when searching within a specific document.';