-- Create the document_chunks table
CREATE TABLE IF NOT EXISTS document_chunks (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  document_id UUID NOT NULL,
  content TEXT,
  metadata JSONB,
  embedding VECTOR(1536),
  chunk_index INTEGER,
  section TEXT,
  page_number INTEGER,
  created_at TIMESTAMPTZ DEFAULT NOW(),
  updated_at TIMESTAMPTZ DEFAULT NOW()
);

-- Create the vector_similarity_searches table
CREATE TABLE IF NOT EXISTS vector_similarity_searches (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  user_id UUID,
  query_text TEXT,
  query_embedding VECTOR(1536),
  search_results JSONB,
  filters JSONB,
  limit_count INTEGER,
  similarity_threshold REAL,
  processing_time_ms INTEGER,
  created_at TIMESTAMPTZ DEFAULT NOW()
);

-- Create the function to count distinct documents
CREATE OR REPLACE FUNCTION count_distinct_documents()
RETURNS INTEGER AS $$
BEGIN
  RETURN (SELECT COUNT(DISTINCT document_id) FROM document_chunks);
END;
$$ LANGUAGE plpgsql;

-- Create the function to get the average chunk size
CREATE OR REPLACE FUNCTION average_chunk_size()
RETURNS INTEGER AS $$
BEGIN
  RETURN (SELECT AVG(LENGTH(content)) FROM document_chunks);
END;
$$ LANGUAGE plpgsql;

-- Create the function to get search analytics
CREATE OR REPLACE FUNCTION get_search_analytics(user_id_param UUID, days_param INTEGER)
RETURNS TABLE(query_text TEXT, search_count BIGINT) AS $$
BEGIN
  RETURN QUERY
  SELECT
    vs.query_text,
    COUNT(*) as search_count
  FROM
    vector_similarity_searches vs
  WHERE
    vs.user_id = user_id_param AND
    vs.created_at >= NOW() - (days_param * INTERVAL '1 day')
  GROUP BY
    vs.query_text
  ORDER BY
    search_count DESC
  LIMIT 20;
END;
$$ LANGUAGE plpgsql;

-- Create the function to get vector database stats
CREATE OR REPLACE FUNCTION get_vector_database_stats()
RETURNS TABLE(total_chunks BIGINT, total_documents BIGINT, average_similarity REAL) AS $$
BEGIN
  RETURN QUERY
  SELECT
    (SELECT COUNT(*) FROM document_chunks),
    (SELECT COUNT(DISTINCT document_id) FROM document_chunks),
    (SELECT AVG(similarity_score) FROM document_similarities WHERE similarity_score > 0);
END;
$$ LANGUAGE plpgsql;