-- FLOW-TWO fixture — a MIXED-TYPE consist, for the wagon-pool scenario (TC-08).
--
-- Run AFTER seed-import-corridor.sql and seed-g1-train.sql. Idempotent.
--
-- WHY A SEPARATE TRAIN
--
-- TRN-G1-1 is 53 × NW5 — one wagon type. On that consist "container booking
-- can't consume flatbed wagons" is untestable: there is only one pool, so the
-- abstract slot count and the physical stock count are the same number and a
-- broken pool separation is invisible.
--
-- TRN-F2-MIX splits the consist across two types the cargo allow-lists do NOT
-- share:
--   30 × NW5 — the type 20FT/40FT containers ride (seed-import-corridor 2b)
--   20 × PW2 — the type E2E_IMP_GRAINS bulk rides (seed-import-corridor 4)
--
-- So 50 abstract slots, but a container booking may only ever draw on 30 of
-- them and a grains booking on 20. A 40-wagon container booking sees "50 free"
-- from CorridorBudget and must still be refused/split by WagonStockLedger —
-- which is the whole assertion (wagon-stock-ledger.util.ts header: "money taken
-- for space that never existed").
--
-- LENGTH MUST NOT BIND. NW5 is 13.966 m, PW2 is 17.066 m:
--   30 × 13.966 + 20 × 17.066 = 418.98 + 341.32 = 760.3 m
-- which is EXACTLY over a 760 m loco. The locos below run 900 m so the length
-- axis stays slack and TC-08 fails only on the pool separation it is testing.
-- Pull: 9000T against 50 wagons of tare+cargo is far under. Slots and TYPE bind.

-- 1. Locomotive pair, 900 m so the mixed consist's length never binds.
INSERT INTO freight.locomotives
  (id, code, max_pull_weight_tons, max_train_length_meters,
   overage_tolerance_tons, current_yard_id)
SELECT gen_random_uuid(), v.code, 9000, 900, 0, y.id
FROM (VALUES ('LOCO-F2-A'), ('LOCO-F2-B')) AS v(code)
JOIN freight.yards y ON y.code = 'DJIB_PORT'
WHERE NOT EXISTS (SELECT 1 FROM freight.locomotives l WHERE l.code = v.code);

UPDATE freight.locomotives
SET max_pull_weight_tons = 9000, max_train_length_meters = 900,
    overage_tolerance_tons = 0,
    current_yard_id = (SELECT id FROM freight.yards WHERE code = 'DJIB_PORT')
WHERE code IN ('LOCO-F2-A', 'LOCO-F2-B')
  AND (max_pull_weight_tons IS DISTINCT FROM 9000
       OR max_train_length_meters IS DISTINCT FROM 900
       OR overage_tolerance_tons IS DISTINCT FROM 0);

-- 2. The train, parked at the corridor origin (a built-train schedule requires it).
INSERT INTO freight.trains
  (id, code, train_name, capacity_tons, current_yard_id,
   import_train_number, export_train_number)
SELECT gen_random_uuid(), 'TRN-F2-MIX', 'E2E Flow-2 Mixed Consist', 3500, y.id,
       '9302', '9301'
FROM freight.yards y
WHERE y.code = 'DJIB_PORT'
  AND NOT EXISTS (SELECT 1 FROM freight.trains t WHERE t.code = 'TRN-F2-MIX');

INSERT INTO freight.train_locomotives (id, train_id, locomotive_id, sequence_no)
SELECT gen_random_uuid(), t.id, l.id, v.seq
FROM (VALUES ('LOCO-F2-A', 0), ('LOCO-F2-B', 1)) AS v(loco_code, seq)
JOIN freight.trains t ON t.code = 'TRN-F2-MIX'
JOIN freight.locomotives l ON l.code = v.loco_code
WHERE NOT EXISTS (
  SELECT 1 FROM freight.train_locomotives tl
  WHERE tl.train_id = t.id AND tl.locomotive_id = l.id
);

-- 3a. Thirty NW5 (container-capable) wagons.
INSERT INTO freight.wagons (id, wagon_number, wagon_type_id, current_yard_id)
SELECT gen_random_uuid(), 'WGN-F2C-' || lpad(g::text, 2, '0'), wt.id, y.id
FROM generate_series(1, 30) AS g
JOIN freight.wagon_types wt ON wt.code = 'NW5'
JOIN freight.yards y ON y.code = 'DJIB_PORT'
WHERE NOT EXISTS (
  SELECT 1 FROM freight.wagons w
  WHERE w.wagon_number = 'WGN-F2C-' || lpad(g::text, 2, '0')
);

-- 3b. Twenty PW2 (bulk-grains) wagons — NOT container-capable.
INSERT INTO freight.wagons (id, wagon_number, wagon_type_id, current_yard_id)
SELECT gen_random_uuid(), 'WGN-F2B-' || lpad(g::text, 2, '0'), wt.id, y.id
FROM generate_series(1, 20) AS g
JOIN freight.wagon_types wt ON wt.code = 'PW2'
JOIN freight.yards y ON y.code = 'DJIB_PORT'
WHERE NOT EXISTS (
  SELECT 1 FROM freight.wagons w
  WHERE w.wagon_number = 'WGN-F2B-' || lpad(g::text, 2, '0')
);

-- 4. Couple all 50, containers first. Unconditionally re-asserted: a prior run
-- could have left one detached, and a 49-wagon consist shifts TC-08's premise.
UPDATE freight.wagons w
SET train_id = t.id,
    sequence_number = g.seq,
    status = 'ASSIGNED',
    current_yard_id = t.current_yard_id
FROM freight.trains t,
     LATERAL (
       SELECT ('WGN-F2C-' || lpad(s::text, 2, '0')) AS num, s AS seq
       FROM generate_series(1, 30) AS s
       UNION ALL
       SELECT ('WGN-F2B-' || lpad(s::text, 2, '0')), 30 + s
       FROM generate_series(1, 20) AS s
     ) g
WHERE t.code = 'TRN-F2-MIX'
  AND w.wagon_number = g.num
  AND (w.train_id IS DISTINCT FROM t.id
       OR w.sequence_number IS DISTINCT FROM g.seq
       OR w.status IS DISTINCT FROM 'ASSIGNED');