-- 共享知识库 (Shared Knowledge Base) 初始化脚本
-- pgvector 扩展及基础条目库
CREATE EXTENSION IF NOT EXISTS vector;
CREATE EXTENSION IF NOT EXISTS pg_trgm;

CREATE TABLE IF NOT EXISTS kb_documents (
    id BIGSERIAL PRIMARY KEY,
    title TEXT NOT NULL,
    doc_no TEXT NOT NULL DEFAULT '',
    category TEXT NOT NULL DEFAULT '',
    content TEXT NOT NULL,
    embedding vector(1024),
    metadata JSONB NOT NULL DEFAULT '{}'::jsonb,
    is_active BOOLEAN NOT NULL DEFAULT true,
    created_at TIMESTAMPTZ NOT NULL DEFAULT now(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT now()
);

CREATE INDEX IF NOT EXISTS idx_kb_doc_title ON kb_documents USING gin (title gin_trgm_ops);
CREATE INDEX IF NOT EXISTS idx_kb_doc_no ON kb_documents(doc_no);
CREATE INDEX IF NOT EXISTS idx_kb_category ON kb_documents(category);

-- 共享法规/知识切片表
CREATE TABLE IF NOT EXISTS kb_chunks (
    id BIGSERIAL PRIMARY KEY,
    document_id BIGINT REFERENCES kb_documents(id) ON DELETE CASCADE,
    chunk_index INT NOT NULL DEFAULT 0,
    chunk_text TEXT NOT NULL,
    embedding vector(1024),
    tokens_count INT NOT NULL DEFAULT 0,
    created_at TIMESTAMPTZ NOT NULL DEFAULT now()
);

CREATE INDEX IF NOT EXISTS idx_kb_chunk_doc ON kb_chunks(document_id);