/**
 * Merge YG-1 drafts.
 *
 *   PO26073102STK  (existing draft, 4 HSS drill-bit lines, 2026-07-31)
 *   PO26080301STK  (new draft, 16 tap lines, loaded 2026-08-03 from quote SOQ078608)
 *
 * Both are still in `draft` status (neither has been sent to the supplier),
 * so the merge is purely local — the supplier hasn't seen either PO number.
 *
 * ## Direction
 *
 * Keep the older PO number (`PO26073102STK`) — it's the operator's
 * existing accumulated draft per the system's "one draft per supplier"
 * design (see `stock-quick-draft-service.ts`). The new draft was created
 * by `2026-08-03-load-yg1-quote-soq078608.ts`; merging its lines back
 * into the existing draft collapses the two into a single draft.
 *
 * ## What this does
 *
 *   1. Updates all 16 `stock_purchase_items` rows on `PO26080301STK`
 *      to point at `PO26073102STK` (just flip the `purchase` field).
 *   2. Deletes the now-empty `PO26080301STK` header.
 *   3. Updates `PO26073102STK`'s `notes` to record both quote sources.
 *
 * The line `id`s, `created` timestamps, `description`, `quantity`,
 * `cost_price`, `notes` (including the "No stock" flag on TS2352932),
 * and `stock_item` references are all preserved — this is a pure
 * parent-pointer swap on the line rows.
 *
 * ## Preconditions
 *
 *   - Both purchase ids exist and are in `status="draft"`.
 *   - Neither has been sent (`email_message_id` is empty, no `documents`).
 *   - The new draft has 16 lines, the old draft has 4.
 *
 * Run: `npx tsx scripts/2026-08-03-merge-yg1-drafts.ts`
 */
import PocketBase from "pocketbase";

const PB_URL = "https://pocketbase-gnqc88suy8fqk6wyryjjdpvl.169.239.180.130.sslip.io";
const ADMIN_EMAIL = "david.els1@outlook.com";
const ADMIN_PASSWORD = "1234567890";

const EXISTING_DRAFT_ID = "2a6qo4nxb2ni4tm"; // PO26073102STK  — keep this one
const NEW_DRAFT_ID = "cj0h9jdsas2s4gk";      // PO26080301STK  — drain into the above

async function main() {
  const pb = new PocketBase(PB_URL);
  await pb.collection("_superusers").authWithPassword(ADMIN_EMAIL, ADMIN_PASSWORD);
  console.log("Authenticated as admin");

  // ── 1. Pre-flight checks ─────────────────────────────────────────
  console.log("\n=== Pre-flight ===");
  const existing = await pb.collection("stock_purchases").getOne(EXISTING_DRAFT_ID);
  const newDraft = await pb.collection("stock_purchases").getOne(NEW_DRAFT_ID);
  console.log(`  PO26073102STK  status=${existing.status}  notes="${existing.notes}"`);
  console.log(`  PO26080301STK  status=${newDraft.status}  notes="${newDraft.notes}"`);
  if (existing.status !== "draft" || newDraft.status !== "draft") {
    throw new Error(`Refusing to merge: both drafts must be in 'draft' status (existing=${existing.status}, new=${newDraft.status})`);
  }
  if (existing.email_message_id || newDraft.email_message_id) {
    throw new Error("Refusing to merge: one or both drafts already have an email_message_id (already sent?)");
  }
  const existingLines = await pb.collection("stock_purchase_items").getList(1, 1, {
    filter: `purchase = "${EXISTING_DRAFT_ID}"`,
  });
  const newLines = await pb.collection("stock_purchase_items").getList(1, 1, {
    filter: `purchase = "${NEW_DRAFT_ID}"`,
  });
  console.log(`  PO26073102STK lines: ${existingLines.totalItems}`);
  console.log(`  PO26080301STK lines: ${newLines.totalItems}`);

  // ── 2. Re-parent the new draft's lines ───────────────────────────
  console.log("\n=== Re-parenting lines ===");
  const newLinesList = await pb
    .collection("stock_purchase_items")
    .getFullList({ filter: `purchase = "${NEW_DRAFT_ID}"`, fields: "id,description,quantity" });
  for (const ln of newLinesList) {
    await pb.collection("stock_purchase_items").update(ln.id, {
      purchase: EXISTING_DRAFT_ID,
    });
    console.log(`  ${ln.id}  →  PO26073102STK  (${ln.description.slice(0, 40)}  qty=${ln.quantity})`);
  }

  // ── 3. Delete the empty new draft ────────────────────────────────
  console.log("\n=== Deleting empty draft PO26080301STK ===");
  await pb.collection("stock_purchases").delete(NEW_DRAFT_ID);
  console.log(`  deleted ${NEW_DRAFT_ID}`);

  // ── 4. Update notes on the surviving draft ───────────────────────
  console.log("\n=== Updating notes on PO26073102STK ===");
  const mergedNotes =
    "YG-1 stock draft. Sources: existing draft since 2026-07-31 (4 HSS drill-bit lines) + YG-1 quote SOQ078608 dated 2026-08-03 for customer CNL001 (16 line items, merged 2026-08-03).";
  await pb.collection("stock_purchases").update(EXISTING_DRAFT_ID, {
    notes: mergedNotes,
  });
  console.log(`  set notes: "${mergedNotes}"`);

  // ── 5. Verify ────────────────────────────────────────────────────
  console.log("\n=== Post-merge verification ===");
  const finalDraft = await pb.collection("stock_purchases").getOne(EXISTING_DRAFT_ID, {
    expand: "supplier",
  });
  const finalLines = await pb.collection("stock_purchase_items").getList(1, 1, {
    filter: `purchase = "${EXISTING_DRAFT_ID}"`,
  });
  console.log(`  Purchase: ${finalDraft.purchase_number}  (${finalDraft.expand?.supplier?.suppliername})`);
  console.log(`  Status:   ${finalDraft.status}`);
  console.log(`  Lines:    ${finalLines.totalItems}`);
  const totalCost = await pb
    .collection("stock_purchase_items")
    .getFullList({ filter: `purchase = "${EXISTING_DRAFT_ID}"` });
  const total = totalCost.reduce((s, l) => s + l.quantity * l.cost_price, 0);
  console.log(`  Total cost (post-discount, excl VAT): R ${total.toFixed(2)}`);

  // Confirm the new-draft id is gone.
  try {
    await pb.collection("stock_purchases").getOne(NEW_DRAFT_ID);
    throw new Error("New draft still exists after delete!");
  } catch (err) {
    if (err instanceof Error && err.message.includes("not found")) {
      console.log(`  PO26080301STK (${NEW_DRAFT_ID}): deleted ✓`);
    } else {
      throw err;
    }
  }
}

main().catch((err) => {
  console.error("FATAL:", err);
  process.exit(1);
});