-- Comments table for proposal discussions
CREATE TABLE comments (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    proposal_id UUID NOT NULL REFERENCES proposals(id) ON DELETE CASCADE,
    author_id UUID NOT NULL REFERENCES users(id),
    content TEXT NOT NULL,
    parent_id UUID REFERENCES comments(id) ON DELETE CASCADE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE INDEX idx_comments_proposal ON comments(proposal_id);
CREATE INDEX idx_comments_parent ON comments(parent_id);

CREATE TRIGGER comments_updated_at BEFORE UPDATE ON comments
    FOR EACH ROW EXECUTE FUNCTION update_updated_at();