-- t-paliad-183 / Fristen Phase 3 Slice 2 Step B-2 — backfill
-- paliad.deadline_rules.priority from the legacy (is_mandatory,
-- is_optional) pair per DESIGN §2.3 (NOT the inverted mapping in
-- head's msg 1746 — head's clarification msg 1750 rules in favour of
-- the design doc).
--
-- Final mapping (design §2.3 + RoP.151 / mig 068 t-paliad-157 semantic):
--
--   is_mandatory=true,  is_optional=false  →  'mandatory'    (statutory must,
--                                                             ☑ pre-checked in
--                                                             save modal)
--   is_mandatory=true,  is_optional=true   →  'optional'     (statutorily strict
--                                                             ONCE IT APPLIES,
--                                                             but applies only
--                                                             if a party files —
--                                                             RoP.151 is the
--                                                             canonical case;
--                                                             ☐ pre-unchecked)
--   is_mandatory=false, is_optional=true   →  'recommended'  (no live data, but
--                                                             defensive default
--                                                             so the CHECK
--                                                             constraint stays
--                                                             satisfied if such
--                                                             a row ever lands)
--   is_mandatory=false, is_optional=false  →  'recommended'  (situational filings
--                                                             — Berufungserwiderung,
--                                                             Replik, Duplik,
--                                                             R.19 Preliminary
--                                                             Objection, R.116
--                                                             EPÜ, Anschluss-
--                                                             berufung, etc.
--                                                             Default-save with
--                                                             override, not
--                                                             'informational'
--                                                             which would make
--                                                             them never-saveable)
--
-- Live-data expected delta (172 rules total, mig 078 set every row to
-- the default 'mandatory'):
--   T/F  (153 rows) → 'mandatory'   — 153 no-op UPDATEs (already correct)
--   T/T  (  1 row)  → 'optional'    — 1 row flips
--   F/F  ( 18 rows) → 'recommended' — 18 rows flip
--   F/T  (  0 rows) → 'recommended' — 0 rows (no live data)
--
-- The UPDATE is split into branches with explicit WHERE clauses so the
-- audit log records each branch as a distinct backfill action (separate
-- audit row chains by (is_mandatory, is_optional) shape). It also keeps
-- the migration idempotent: re-running only touches rows whose priority
-- doesn't already match the target.
--
-- Audit-reason cites design §2.3 — that's the persistent rationale in
-- the paliad.deadline_rule_audit log.

SELECT set_config(
    'paliad.audit_reason',
    'backfill 083: priority from (is_mandatory, is_optional) per design §2.3 — '
        || 'T/T→optional (RoP.151), F/F→recommended (situational filings)',
    true);

-- Branch 1: T/T → 'optional' (RoP.151).
UPDATE paliad.deadline_rules
   SET priority = 'optional'
 WHERE is_mandatory = true
   AND is_optional  = true
   AND priority    <> 'optional';

-- Branch 2: F/F → 'recommended'.
UPDATE paliad.deadline_rules
   SET priority = 'recommended'
 WHERE is_mandatory = false
   AND is_optional  = false
   AND priority    <> 'recommended';

-- Branch 3: F/T → 'recommended' (defensive; no live rows today).
UPDATE paliad.deadline_rules
   SET priority = 'recommended'
 WHERE is_mandatory = false
   AND is_optional  = true
   AND priority    <> 'recommended';

-- Branch 4: T/F → 'mandatory'. Skipped explicitly: the mig 078 column
-- default is already 'mandatory', so every T/F row already has the
-- correct value. A defensive UPDATE here would write 153 needless
-- audit rows. Leave T/F untouched.

DO $$
DECLARE
    n_mand int;
    n_opt  int;
    n_reco int;
    n_info int;
    n_null int;
BEGIN
    SELECT count(*) FILTER (WHERE priority = 'mandatory'),
           count(*) FILTER (WHERE priority = 'optional'),
           count(*) FILTER (WHERE priority = 'recommended'),
           count(*) FILTER (WHERE priority = 'informational'),
           count(*) FILTER (WHERE priority IS NULL)
      INTO n_mand, n_opt, n_reco, n_info, n_null
      FROM paliad.deadline_rules;
    RAISE NOTICE 'backfill 083: priority distribution — '
                 'mandatory=%, optional=%, recommended=%, informational=%, NULL=%',
                 n_mand, n_opt, n_reco, n_info, n_null;
    -- Hard assertion: priority is NOT NULL by schema (mig 078) and
    -- every value must lie in the CHECK enum. n_null must be 0.
    IF n_null > 0 THEN
        RAISE EXCEPTION 'backfill 083: % rows still have priority IS NULL — '
                        'schema violation', n_null;
    END IF;
END $$;