-- RAG knowledge base initialization SQL
-- Applied to agent_memory database via CNPG Database resource

CREATE EXTENSION IF NOT EXISTS vector;

CREATE TABLE IF NOT EXISTS documents (
    id            UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    content       TEXT NOT NULL,
    metadata      JSONB DEFAULT '{}'::jsonb,
    embedding     vector(768),
    created_at    TIMESTAMPTZ NOT NULL DEFAULT now(),
    updated_at    TIMESTAMPTZ NOT NULL DEFAULT now()
);

CREATE INDEX IF NOT EXISTS idx_documents_embedding_hnsw
    ON documents USING hnsw (embedding vector_cosine_ops);

CREATE INDEX IF NOT EXISTS idx_documents_content
    ON documents USING gin (to_tsvector('english', content));

CREATE INDEX IF NOT EXISTS idx_documents_metadata
    ON documents USING gin (metadata);

CREATE OR REPLACE FUNCTION update_documents_updated_at()
RETURNS TRIGGER AS $$
BEGIN
    NEW.updated_at = now();
    RETURN NEW;
END;
$$ LANGUAGE plpgsql;

CREATE TRIGGER trg_documents_updated_at
    BEFORE UPDATE ON documents
    FOR EACH ROW
    EXECUTE FUNCTION update_documents_updated_at();