-- CSG 长期归档修复 (2026-09-21)
-- 背景：TimescaleDB 任务 1008 `csg_daily_snapshot()` 自 2026-08-29 创建起 0 成功 / 294 失败。
--   原因：函数签名是零参数 `csg_daily_snapshot()`，而 TimescaleDB 自定义 job 动作
--   按名字调用 `schema.proc(job_id integer, config jsonb)`，解析不到 → 每次报
--   `function or procedure "public.csg_daily_snapshot(integer, jsonb)" does not exist`。
--   后果：csg_history 的 day 行停在 2026-08-28、month 行停在 2026-08-01（且 2026-08 的
--   month 行是 08-29 当时的「本月至今」302.47 kWh / 180.28 元，不是月终值 331.22 / 198.65）。
--
-- 本文件的三个动作（幂等，可重复执行）：
--   1. `csg_ladder_cost(kwh, month)` —— 阶梯电价助手（广州：夏季 5-10 月 260/600，
--      非夏季 200/400；0.589 / 0.639 / 0.889 元每 kWh）。归档侧的唯一计价来源。
--   2. `csg_daily_snapshot(job_id integer, config jsonb)` v3 —— 兼容 TimescaleDB job 签名；
--      并把 month 行按「数据日期 d 所属月份」归属：
--        · d 属于当前月 → usage 取集成本月累计，cost 用阶梯助手重算
--        · d 属于上月   → usage 由该月 day 行汇总（不读集成 last_month，避开翻月瞬态：
--                        2026-08-31 16:32 实测 last_month_total_usage 曾读到 323.49 这种误值）
--      并加「不降级」保护：day 行汇总结果小于已记录的 month 行时不动。
--   3. 回填 2026-08-29 → 2026-09-19 的 day 行（数据源：08-29..08-31 取 scribe
--      states_raw 里 `yesterday_kwh` 观测值减一天；09-01..09-19 取 CSG 集成
--      `this_month_by_day`，其中 09-06 = 9.29 是 scribe 漏采的观测）。日费用一律用
--      「当日用电 × 当日所处的边际档位」计算，使整月 day 费用之和 == 阶梯月费用。
--
-- 回滚（脚本内已自动建快照表 csg_history_bak_20260921）：
--   BEGIN;
--     SELECT delete_job((SELECT job_id FROM timescaledb_information.jobs WHERE proc_name='csg_daily_snapshot'));
--     DROP FUNCTION IF EXISTS public.csg_daily_snapshot(integer, jsonb);
--     CREATE FUNCTION public.csg_daily_snapshot() RETURNS void LANGUAGE plpgsql AS $f$ ...原函数体... $f$;
--     SELECT add_job('public.csg_daily_snapshot'::regproc, INTERVAL '1 day');
--     DROP FUNCTION IF EXISTS public.csg_ladder_cost(numeric, date);
--     DELETE FROM csg_history; INSERT INTO csg_history SELECT * FROM csg_history_bak_20260921;
--   COMMIT;
--   （或整体放弃归档：DROP TABLE csg_history + 删任务，见 hosts/pgdb.md 回滚段）

\set ON_ERROR_STOP on

BEGIN;

-- ---------- 0. 回滚快照（只建一次） ----------
CREATE TABLE IF NOT EXISTS public.csg_history_bak_20260921 AS TABLE public.csg_history;

-- ---------- 1. 阶梯电价助手 ----------
CREATE OR REPLACE FUNCTION public.csg_ladder_cost(kwh numeric, month_date date)
RETURNS numeric
LANGUAGE sql
IMMUTABLE
AS $function$
  SELECT CASE
    WHEN kwh IS NULL OR kwh <= 0 THEN 0::numeric
    WHEN kwh <= (CASE WHEN extract(month FROM month_date) BETWEEN 5 AND 10 THEN 260 ELSE 200 END)
      THEN round(kwh * 0.589, 2)
    WHEN kwh <= (CASE WHEN extract(month FROM month_date) BETWEEN 5 AND 10 THEN 600 ELSE 400 END)
      THEN round((CASE WHEN extract(month FROM month_date) BETWEEN 5 AND 10 THEN 260 ELSE 200 END) * 0.589
                 + (kwh - (CASE WHEN extract(month FROM month_date) BETWEEN 5 AND 10 THEN 260 ELSE 200 END)) * 0.639, 2)
    ELSE round((CASE WHEN extract(month FROM month_date) BETWEEN 5 AND 10 THEN 260 ELSE 200 END) * 0.589
               + ((CASE WHEN extract(month FROM month_date) BETWEEN 5 AND 10 THEN 600 ELSE 400 END)
                  - (CASE WHEN extract(month FROM month_date) BETWEEN 5 AND 10 THEN 260 ELSE 200 END)) * 0.639
               + (kwh - (CASE WHEN extract(month FROM month_date) BETWEEN 5 AND 10 THEN 600 ELSE 400 END)) * 0.889, 2)
  END;
$function$;

-- ---------- 2. 重建为 TimescaleDB 兼容签名的 v3 + 重挂 job ----------
-- 注意：不能直接 DROP 旧函数——TimescaleDB job 1008 持有依赖
-- （ERROR: cannot drop public.csg_daily_snapshot because background job 1008 depends on it）。
-- 因此：delete_job → 换签名重建函数 → add_job 重挂，并把排程对齐文档口径
-- （22:30 Asia/Shanghai = 14:30 UTC；原来实际跑在 22:00 UTC = 06:00 CST，
--  那个时点集成还没发布前一日数据，d 会晚一天）。
DO $do$
BEGIN
  IF EXISTS (SELECT 1 FROM timescaledb_information.jobs WHERE job_id = 1008) THEN
    PERFORM delete_job(1008);
  END IF;
END
$do$;

DROP FUNCTION IF EXISTS public.csg_daily_snapshot();

CREATE OR REPLACE FUNCTION public.csg_daily_snapshot(
    job_id integer DEFAULT NULL,
    config jsonb DEFAULT NULL
)
RETURNS void
LANGUAGE plpgsql
AS $function$
DECLARE
  d date;
  v_usage numeric; v_cost numeric; v_ladder text; v_balance numeric;
  m_usage numeric; v_tariff numeric;
  p_month date; p_usage numeric; prev_usage numeric;
BEGIN
  -- 数据日期 = CSG 集成「最新一天」（数据滞后一天）；COALESCE 兜底昨天
  SELECT COALESCE(
    (SELECT (attributes->>'latest_day_date')::date
       FROM states_raw s JOIN entities e ON e.id = s.metadata_id
      WHERE e.entity_id = 'sensor.0800041935246530_latest_day_kwh'
      ORDER BY s.time DESC LIMIT 1),
    CURRENT_DATE - 1) INTO d;

  -- 一律取「最新有值行」：轮询先写瞬态 unknown、~4s 后才写有值行
  SELECT s.value INTO v_usage  FROM states_raw s JOIN entities e ON e.id=s.metadata_id
    WHERE e.entity_id='sensor.0800041935246530_yesterday_kwh' AND s.value IS NOT NULL ORDER BY s.time DESC LIMIT 1;
  SELECT s.value INTO v_cost   FROM states_raw s JOIN entities e ON e.id=s.metadata_id
    WHERE e.entity_id='sensor.0800041935246530_latest_day_cost' AND s.value IS NOT NULL ORDER BY s.time DESC LIMIT 1;
  SELECT s.state INTO v_ladder FROM states_raw s JOIN entities e ON e.id=s.metadata_id
    WHERE e.entity_id='sensor.csg_current_ladder' AND s.state IS NOT NULL AND s.state NOT IN ('unknown','unavailable') ORDER BY s.time DESC LIMIT 1;
  SELECT s.value INTO v_balance FROM states_raw s JOIN entities e ON e.id=s.metadata_id
    WHERE e.entity_id='sensor.0800041935246530_balance' AND s.value IS NOT NULL ORDER BY s.time DESC LIMIT 1;
  SELECT s.value INTO m_usage  FROM states_raw s JOIN entities e ON e.id=s.metadata_id
    WHERE e.entity_id='sensor.0800041935246530_this_month_total_usage' AND s.value IS NOT NULL ORDER BY s.time DESC LIMIT 1;
  -- 日费用回退：原生 latest_day_cost 从未有值（集成侧该传感器恒为 unknown），
  -- 用「昨日用电 × 当前档费率」估计；账单口径可用时优先原生
  SELECT s.value INTO v_tariff FROM states_raw s JOIN entities e ON e.id=s.metadata_id
    WHERE e.entity_id='sensor.csg_current_ladder_tariff' AND s.value IS NOT NULL ORDER BY s.time DESC LIMIT 1;
  IF v_cost IS NULL AND v_usage IS NOT NULL AND v_tariff IS NOT NULL THEN
    v_cost := v_usage * v_tariff;
  END IF;

  INSERT INTO csg_history (period, kind, usage_kwh, cost, ladder, balance)
  VALUES (d, 'day', v_usage, v_cost, v_ladder, v_balance)
  ON CONFLICT (period, kind) DO UPDATE SET
    usage_kwh  = COALESCE(EXCLUDED.usage_kwh,  csg_history.usage_kwh),
    cost       = COALESCE(EXCLUDED.cost,       csg_history.cost),
    ladder     = COALESCE(EXCLUDED.ladder,     csg_history.ladder),
    balance    = COALESCE(EXCLUDED.balance,    csg_history.balance),
    updated_at = now();

  -- month 行按 d 所属月份归属（v3：修掉翻月时用错月份累计的 bug）
  p_month := date_trunc('month', d)::date;

  IF p_month = date_trunc('month', CURRENT_DATE)::date THEN
    -- 当月：集成本月累计优先，缺失则退回 day 行汇总；费用一律阶梯重算
    SELECT COALESCE(m_usage, sum(h.usage_kwh)) INTO p_usage
      FROM csg_history h
     WHERE h.kind='day' AND h.period >= p_month AND h.period < (p_month + interval '1 month');
  ELSE
    -- 上月/更早：只信该月 day 行（集成翻月时 last_month_* 有瞬态误值）
    SELECT sum(h.usage_kwh) INTO p_usage
      FROM csg_history h
     WHERE h.kind='day' AND h.period >= p_month AND h.period < (p_month + interval '1 month');
    SELECT h.usage_kwh INTO prev_usage FROM csg_history h
     WHERE h.kind='month' AND h.period = p_month;
    IF p_usage IS NULL OR (prev_usage IS NOT NULL AND prev_usage > p_usage) THEN
      RETURN;  -- day 行不完整，保留已有 month 行，不降级
    END IF;
  END IF;

  IF p_usage IS NOT NULL AND p_usage > 0 THEN
    INSERT INTO csg_history (period, kind, usage_kwh, cost)
    VALUES (p_month, 'month', p_usage, public.csg_ladder_cost(p_usage, p_month))
    ON CONFLICT (period, kind) DO UPDATE SET
      usage_kwh  = EXCLUDED.usage_kwh,
      cost       = EXCLUDED.cost,
      updated_at = now();
  END IF;
END $function$;

-- 重挂每日任务：22:30 Asia/Shanghai（14:30 UTC）
DO $do$
BEGIN
  IF NOT EXISTS (SELECT 1 FROM timescaledb_information.jobs WHERE proc_name = 'csg_daily_snapshot') THEN
    PERFORM add_job(proc              => 'public.csg_daily_snapshot'::regproc,
                    schedule_interval => INTERVAL '1 day',
                    initial_start     => date_trunc('day', now() AT TIME ZONE 'UTC')
                                         + INTERVAL '14 hours 30 minutes',
                    timezone          => 'UTC');
  END IF;
END
$do$;

-- ---------- 3. 回填 day 行 2026-08-29 .. 2026-09-19 + 重算月行 ----------
-- 现有 day 行（07-01..08-28 来自首批回填）与新行一起参与「月内累计」窗口，
-- 使边际档位计算正确；已有非空 cost 不覆盖。
WITH newrows(period, usage_kwh) AS (
  VALUES
    (DATE '2026-08-29', 10.99::numeric),
    (DATE '2026-08-30', 10.03::numeric),
    (DATE '2026-08-31',  7.73::numeric),
    (DATE '2026-09-01',  8.50::numeric),
    (DATE '2026-09-02',  6.68::numeric),
    (DATE '2026-09-03',  8.74::numeric),
    (DATE '2026-09-04',  6.76::numeric),
    (DATE '2026-09-05',  7.76::numeric),
    (DATE '2026-09-06',  9.29::numeric),
    (DATE '2026-09-07',  7.24::numeric),
    (DATE '2026-09-08', 13.00::numeric),
    (DATE '2026-09-09',  7.98::numeric),
    (DATE '2026-09-10',  8.16::numeric),
    (DATE '2026-09-11',  8.75::numeric),
    (DATE '2026-09-12', 10.48::numeric),
    (DATE '2026-09-13', 11.11::numeric),
    (DATE '2026-09-14',  7.22::numeric),
    (DATE '2026-09-15',  9.94::numeric),
    (DATE '2026-09-16',  7.19::numeric),
    (DATE '2026-09-17', 10.32::numeric),
    (DATE '2026-09-18',  7.77::numeric),
    (DATE '2026-09-19', 11.79::numeric)
),
allrows AS (
  SELECT h.period, h.usage_kwh FROM csg_history h
   WHERE h.kind='day' AND h.period BETWEEN DATE '2026-07-01' AND DATE '2026-09-19'
  UNION ALL
  SELECT n.period, n.usage_kwh FROM newrows n
   WHERE NOT EXISTS (SELECT 1 FROM csg_history h WHERE h.kind='day' AND h.period = n.period)
),
calc AS (
  SELECT period, usage_kwh,
         CASE WHEN extract(month FROM period) BETWEEN 5 AND 10 THEN 260 ELSE 200 END AS t1,
         CASE WHEN extract(month FROM period) BETWEEN 5 AND 10 THEN 600 ELSE 400 END AS t2,
         sum(usage_kwh) OVER (PARTITION BY date_trunc('month', period)
                              ORDER BY period ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS c1
    FROM allrows
),
slab AS (
  SELECT period, usage_kwh, t1, t2, c1, c1 - usage_kwh AS c0 FROM calc
),
priced AS (
  SELECT period, usage_kwh,
         round(
           (CASE WHEN c1 <= t1 THEN c1*0.589
                 WHEN c1 <= t2 THEN t1*0.589 + (c1-t1)*0.639
                 ELSE t1*0.589 + (t2-t1)*0.639 + (c1-t2)*0.889 END)
         - (CASE WHEN c0 <= t1 THEN c0*0.589
                 WHEN c0 <= t2 THEN t1*0.589 + (c0-t1)*0.639
                 ELSE t1*0.589 + (t2-t1)*0.639 + (c0-t2)*0.889 END), 2) AS cost,
         CASE WHEN c1 <= t1 THEN '一档' WHEN c1 <= t2 THEN '二档' ELSE '三档' END AS ladder
    FROM slab
)
INSERT INTO csg_history (period, kind, usage_kwh, cost, ladder)
SELECT period, 'day', usage_kwh, cost, ladder FROM priced
ON CONFLICT (period, kind) DO UPDATE SET
  usage_kwh  = EXCLUDED.usage_kwh,
  cost       = COALESCE(csg_history.cost, EXCLUDED.cost),
  ladder     = COALESCE(csg_history.ladder, EXCLUDED.ladder),
  updated_at = now();

-- 月行按 day 行汇总重算（只动 2026-08 / 2026-09；2026-07 及更早的月行来自集成
-- by_month，day 行并不覆盖整月，重算会把它算小，故不触碰）
INSERT INTO csg_history (period, kind, usage_kwh, cost)
SELECT date_trunc('month', h.period)::date, 'month', round(sum(h.usage_kwh),2),
       public.csg_ladder_cost(round(sum(h.usage_kwh),2), date_trunc('month', h.period)::date)
  FROM csg_history h
 WHERE h.kind='day' AND h.period BETWEEN DATE '2026-08-01' AND DATE '2026-09-30'
 GROUP BY date_trunc('month', h.period)
ON CONFLICT (period, kind) DO UPDATE SET
  usage_kwh  = EXCLUDED.usage_kwh,
  cost       = EXCLUDED.cost,
  updated_at = now();

COMMIT;