-- SCHEMA-03 (D-03/D-04) — TenderSource 1:n model + Tender.fingerprint.
--
-- Two-step ordering (Pitfall 5, 13-RESEARCH.md): (1) create the table and
-- add the additive Tender.fingerprint column BEFORE (2) backfilling
-- TenderSource rows from the pre-existing ~2851 DÖE Tender rows, and only
-- THEN activating the unique constraint. DÖE sourceNoticeIds are live-unique
-- (0% NULL OCID) so the backfill insert itself will not violate the
-- constraint, but the ordering is kept strict regardless.
--
-- fingerprint backfill (Tender.fingerprint) is NOT done here in SQL — the
-- umlaut/CPV-division normalization it needs lives in code
-- (tender-fingerprint.ts). It is populated by the one-time TS script
-- `backfill-tender-source.ts`, run once after this migration is applied.

-- Step 1a: additive nullable column on Tender.
ALTER TABLE "Tender" ADD COLUMN "fingerprint" TEXT;
CREATE INDEX "Tender_fingerprint_idx" ON "Tender"("fingerprint");

-- Step 1b: TenderSource table.
CREATE TABLE "TenderSource" (
    "id" TEXT NOT NULL,
    "tenderId" TEXT NOT NULL,
    "sourcePortal" TEXT NOT NULL,
    "sourceNoticeId" TEXT NOT NULL,
    "ocid" TEXT,
    "sourceUrl" TEXT,
    "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,

    CONSTRAINT "TenderSource_pkey" PRIMARY KEY ("id")
);

CREATE INDEX "TenderSource_tenderId_idx" ON "TenderSource"("tenderId");

ALTER TABLE "TenderSource" ADD CONSTRAINT "TenderSource_tenderId_fkey"
    FOREIGN KEY ("tenderId") REFERENCES "Tender"("id") ON DELETE CASCADE ON UPDATE CASCADE;

-- Step 2: backfill — one TenderSource row per pre-existing Tender, from its
-- current sourcePortal/sourceNoticeId/sourceUrl/ocid (D-05).
INSERT INTO "TenderSource" (id, "tenderId", "sourcePortal", "sourceNoticeId", ocid, "sourceUrl", "createdAt")
SELECT gen_random_uuid(), t.id, t."sourcePortal", t."sourceNoticeId", t.ocid, t."sourceUrl", now()
FROM "Tender" t;

-- Step 3: unique constraint, applied AFTER the backfill insert succeeds.
CREATE UNIQUE INDEX "TenderSource_sourcePortal_sourceNoticeId_key" ON "TenderSource"("sourcePortal", "sourceNoticeId");