-- 日内新闻候选与验证持久化结构

CREATE TABLE IF NOT EXISTS intraday_news_candidate (
    id BIGSERIAL PRIMARY KEY,
    candidate_date DATE NOT NULL,
    discovered_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
    event_type TEXT NOT NULL,
    provider_name TEXT NOT NULL,
    model_name TEXT,
    provider_country TEXT,
    title TEXT NOT NULL,
    summary TEXT,
    candidate_urls JSONB NOT NULL DEFAULT '[]'::jsonb,
    discovery_source TEXT NOT NULL,
    discovery_query TEXT,
    discovery_evidence JSONB NOT NULL DEFAULT '{}'::jsonb,
    normalized_key TEXT NOT NULL,
    status TEXT NOT NULL DEFAULT 'candidate',
    verification_confidence TEXT NOT NULL DEFAULT 'candidate',
    verification_notes TEXT,
    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
);

DO $$
BEGIN
    IF NOT EXISTS (
        SELECT 1 FROM pg_constraint WHERE conname = 'chk_intraday_news_candidate_status'
    ) THEN
        ALTER TABLE intraday_news_candidate
            ADD CONSTRAINT chk_intraday_news_candidate_status
            CHECK (status IN ('candidate', 'verifying', 'verified', 'rejected', 'stale'));
    END IF;

    IF NOT EXISTS (
        SELECT 1 FROM pg_constraint WHERE conname = 'chk_intraday_news_candidate_confidence'
    ) THEN
        ALTER TABLE intraday_news_candidate
            ADD CONSTRAINT chk_intraday_news_candidate_confidence
            CHECK (verification_confidence IN ('candidate', 'secondary_confirmed', 'official_confirmed'));
    END IF;
END
$$;

CREATE UNIQUE INDEX IF NOT EXISTS idx_intraday_news_candidate_normalized_key
    ON intraday_news_candidate(normalized_key);
CREATE INDEX IF NOT EXISTS idx_intraday_news_candidate_date
    ON intraday_news_candidate(candidate_date DESC, discovered_at DESC);
CREATE INDEX IF NOT EXISTS idx_intraday_news_candidate_status
    ON intraday_news_candidate(status);
CREATE INDEX IF NOT EXISTS idx_intraday_news_candidate_provider_event
    ON intraday_news_candidate(provider_name, event_type, candidate_date DESC);

COMMENT ON TABLE intraday_news_candidate IS '搜索引擎与 LLM 发现的日内新闻候选池，尚未直接进入正式日报事实层';
COMMENT ON COLUMN intraday_news_candidate.candidate_urls IS '候选来源 URL 数组，按发现层输出原样保留';
COMMENT ON COLUMN intraday_news_candidate.discovery_evidence IS '发现阶段原始证据 JSONB，例如搜索命中、LLM 归纳结果';
COMMENT ON COLUMN intraday_news_candidate.normalized_key IS '同日同事件的去重键，避免重复发现候选';

CREATE TABLE IF NOT EXISTS intraday_news_verification (
    id BIGSERIAL PRIMARY KEY,
    candidate_id BIGINT NOT NULL REFERENCES intraday_news_candidate(id) ON DELETE CASCADE,
    verified_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
    verifier_source TEXT NOT NULL,
    verifier_url TEXT,
    verifier_status TEXT NOT NULL,
    extracted_facts JSONB NOT NULL DEFAULT '{}'::jsonb,
    notes TEXT,
    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
);

DO $$
BEGIN
    IF NOT EXISTS (
        SELECT 1 FROM pg_constraint WHERE conname = 'chk_intraday_news_verification_status'
    ) THEN
        ALTER TABLE intraday_news_verification
            ADD CONSTRAINT chk_intraday_news_verification_status
            CHECK (verifier_status IN ('matched', 'contradicted', 'insufficient', 'error'));
    END IF;
END
$$;

CREATE INDEX IF NOT EXISTS idx_intraday_news_verification_candidate_verified_at
    ON intraday_news_verification(candidate_id, verified_at DESC);
CREATE INDEX IF NOT EXISTS idx_intraday_news_verification_source
    ON intraday_news_verification(verifier_source);
CREATE INDEX IF NOT EXISTS idx_intraday_news_verification_status
    ON intraday_news_verification(verifier_status);

COMMENT ON TABLE intraday_news_verification IS '日内新闻候选的验证轨迹，记录验证来源、状态和提取事实';
COMMENT ON COLUMN intraday_news_verification.extracted_facts IS '验证阶段提取出的结构化事实 JSONB';

DO $$
BEGIN
    IF NOT EXISTS (
        SELECT 1
        FROM pg_trigger
        WHERE tgname = 'intraday_news_candidate_updated_at'
    ) THEN
        CREATE TRIGGER intraday_news_candidate_updated_at
        BEFORE UPDATE ON intraday_news_candidate
        FOR EACH ROW
        EXECUTE FUNCTION update_updated_at_column();
    END IF;
END
$$;